Editorial: Prevention of cardiovascular diseases: a spearhead for control of noncommunicable diseases
Pekka Puska1
1Former Director General, National Institute for Health and Welfare, Finland; President, International Association of National Public Health Institutes.
After the Second World War, Western countries were faced with a growing burden of cardiovascular disease (CVD) and cancer, seen then as "diseases of affluence". Classical studies soon identified a few strong and obviously causal risk factors for CVD, especially high serum cholesterol, high blood pressure and smoking (l). Smoking was shown as strong cause of many cancers. It was realized that unlike previous public health problems with communicable diseases, the risk factors are strongly related to certain behaviours.
This research opened the possibilities for prevention, and several preventive trials were started in the United States of America (USA) and Europe. Since the behavioural risk factors strongly reflect lifestyles and their cultural and environmental determinants, it became obvious that any major success from the public health point ofview would call for interventions in whole communities.
Such programmes were, indeed, started in the 1970s and 1980s, first in the USA and Europe (2). Because Finland was faced with an exceptionally high CVD burden, the North Karelia Project was started there, and its long-term experiences and comprehensive evaluation are well known (3). Later, community-based programmes were also launched in several developing countries, for example the Isfahan Healthy Heart Programme in the Islamic Republic of Iran (4).
An important development was the recognition that the behavioural risk factors for CVD are also risk factors for many other noncommunicable diseases (NCDs). Therefore, many community-based programmes began to adopt an "integrated approach to NCD prevention". WHO coordinates many of these programmes, such as the Countrywide Integrated Noncommunicable Diseases Intervention (CINDI) programme in Europe and CARMEN (Actions for the Multifactorial Reduction of Noncommunicable Diseases) in the Americas (5). The experiences of programmes have varied but many have contributed to national preventive actions, as seen in Finland.
As we entered the 21st century, the possibilities and potential for CVD prevention had become clear. At the same time, there has been a rapid change in the global public health situation, with NCDs escalating and currently responsible for about two-thirds of all deaths in the world, half of them due to CVD (6). All this formed the background for the pioneering WHO Global Strategy for the Prevention and Control of NCDs in 2000 (7) and subsequent WHO documents and strategies, which highlighted the integrated prevention of CVD, cancers, chronic lung disease and diabetes by intervening on the four key behaviours: unhealthy diet, physical inactivity and tobacco use and harmful use of alcohol.
In the past few years there has been considerable progress in prevention and control of CVDs. Clinical research on diagnostic and therapeutic possibilities has advanced greatly and benefitted patients with these diseases. Although this is welcome, the increasing costs of clinical medicine place a substantial burden on the health services. And the treatment of chronic diseases is often late, especially with the high proportion of sudden cardiovascular deaths. From the public health point of view, good primary health care with evidence-based but inexpensive interventions, as advocated by WHO, have the greatest impact.
Progress in prevention has continued in two particular areas: high-risk and population-based prevention. The high-risk approach aims at detecting persons with high CVD risk and effectively reducing their risk. In this approach, the key is the detection and accurate assessment of the risk. Early emphasis on individual risk factors has been replaced by assessment of total risk, and many scores have been developed for effective risk assessment, e.g. The Framingham or the European risk scores (8).
Although intervention for a high-risk patient may save his or her life, the direct public health impact of this approach is, at best, limited. Thus, population-based prevention has received increasing attention. Both theory and practice show how the population approach has the greatest potential (9). For instance, in Finland, the approximately 80% reduction in annual CVD mortality in the population under 75 years of age over 30 years and the prevention of some quarter of a million deaths from CVDs during this time in a nation of five million people could never have been achieved through clinical measures (3).
There are many other advantages of the population approach in controlling CVDs. Since the work is based to a great extent on policies and health promotion, it is cheap compared with the high costs of treatment and high-risk interventions. Prevention through changing lifestyles is thus the cost-effective and sustainable way of reducing the CVD burden. Such national interventions can have an impact on several major NCDs and on public health as a whole, and as such can contribute to favourable social and economic development.
With this background, global political attention on NCD prevention has greatly increased in recent years. This culminated in the High-Level Meeting of the General Assembly on the Prevention and Control of Non-communicable Diseases in 2011, which resulted in a political declaration (10). Following the UN declaration and based on decisions with the Member States, WHO has prepared a Global NCD Action Plan 2013-2020, with global targets, indicators and inter-sectoral coordination (6).
The global target is a 25% reduction in avoidable NCD mortality by 2025. To achieve this, there are targets to change diets (especially concerning salt and quality offat), to increase physical activity, and to reduce tobacco use and harmful alcohol use. he lifestyle changes should be reflected in favourable changes in the main biological risk factors: blood pressure, blood cholesterol and body weight - all central factors behind CVDs. The action plan also outlines important elements of surveillance, as well as aspects of improved treatment, advocacy, governance and research.
Since CVD accounts for approximately half of all preventable NCD deaths, it is clear that success or failure in achieving the NCD prevention target depends on success in CVD prevention. Many analyses show that the greatest potential for CVD prevention is in achieving dietary changes in fat, salt and sugar consumption (11,12). It has also been shown recently that reaching the global risk factor targets by 2025 will not quite result in achieving the overall target, but in achieving the CVD target (13).
his is naturally good news, but we must recognize that reaching the targets in many parts of the world will be hard. And to achieve the overall NCD target and further CVD reductions, a more ambitious tobacco reduction target might be warranted and feasible, in view of the many recent achievements in tobacco reduction and with full implementation of the WHO Framework Convention on Tobacco Control.
References
- Relationship of blood pressure, serum cholesterol, smoking habit, relative weight and ECG abnormalities to incidence of major coronary events: final report of the pooling project. The pooling project research group. J Chronic Dis. 1978 Apr;31(4):201-306. PMID:681498
- Puska P, Vartiainen E. Community-based intervention studies in high-income countries. In: Detels R, Beaglehole R, Lansang MA, Gulliford M, editors. Oxford textbook of public health. Oxford: Oxford University Press; 2009:557-66.
- Puska P, Vartiainen E, Laatikainen T, Jousilahti P, Paavola M, editors. The North Karelia Project: from North Karelia to National Action. Helsinki: Helsinki University Printing House; 2009.
- Sarrafzadegan N, Kelishadi R, Sadri G, Malekafzali H, Pour-moghaddas M, Heidari K, et al. Outcomes of a comprehensive healthy lifestyle program on cardiometabolic risk factors in a developing country: the Isfahan Healthy Heart Program. Arch Iran Med. 2013 Jan;16(1):4-11. PMID:23273227
- Protocol and Guidelines: Countrywide Integrated Noncom-municable Diseases Intervention (CINDI) Programme. Copenhagen: WHO Regional Office for Europe; 1996 (EUR/ ICP/CIND 94 02/PB04 (http://whqlibdoc.who.int/hq/1994/ EUR_ICP_CIND_94.02_PB04.pdf, accessed 26 June 2014).
- WHO. Global Action Plan for the Prevention and Control of Noncommunicable diseases 2013-2020. Geneva: World Health Organization; 2013.
- Global strategy for the prevention and control of noncom-municable diseases. Report by the Director-General (http:// apps.who.int/gb/archive/pdf_files/WHA53/ea14.pdf?ua=10, accessed 26 June 2014)
- Tunstall-Pedoe H. Cardiovascular Risk and Risk Scores: ASSIGN, Framingham, QRISK and others: how to choose. Heart. 2011 Mar;97(6):442-4. PMID:21339319
- Kottke TE, Puska P, Salonen JT, Tuomilehto J, Nissinen A. Projected effects of high-risk versus population-based prevention strategies in coronary heart disease. Am J Epidemiol. 1985 May;121(5):697-704. PMID:4014161
- Political Declaration of the High-level Meeting of the General Assembly on the Prevention and Control of Non-communicable Diseases 2011 (http://www.who.int/nmh/events/ un_ncd_summit2011/political_declaration_en.pdf, accessed 26 June 2014)
- Moran A, Tsong K, Forouzanfar M, Roth G, Mensah G, Ezzati M, et al. Variations in Ischaemic Heart Disease Burden and Risk Factors 2010 Study. Global Heart. 2014;9:91-9 (http://download.journals.elsevierhealth.com/pdfs/journals/2211-8160/ PIIS221181601300210X.pdf, accessed 26 June 2014).
- Laatikainen T, Critchley J, Vartiainen E, Salomaa V, Ketonen M, Capewell S. Explaining the decline in coronary heart disease mortality in Finland between 1982 and 1997. Am J Epidemiol. 2005 Oct 15;162(8):764-73. PMID:16150890
- Kontis V, Mathers CD, Rehm J, Stevens GA, Shield KD, Bonita R, et al. Contribution ofsix risk factors to achieving the 25*25 non-communicable disease mortality reduction target: a modelling study. Lancet. 2014 May 2; 10.1016/s0140-6736(14)6 0 616-4 [Epub ahead of print]. PMID:24797573
Breastfeeding practice in Kuwait: determinants of success and reasons for failure
M.F. Nassar,1 A.M. Abdel-Kader,2 F.A. Al-Refaee,3 Y.A. Mohammad,3 S. AlDhafiri,4 S. Gabr4 and S. Al-Qattan4
ممارسات الرضاعة الطبيعية من الثدي في الكويت: محددات النجاخ وأسباب الفشل
مي نصار، علاء عبد القادر، فواز الرفاعى، ياسر محمد، سارة الظفيري، شهيرة جبر، شيماء القطان
الخلاصة: هدفت هذه الدراسة إلى التعرف عل المحددات المحتملة لمدة الإرضاع الطبيعي من الثدي في الكويت لدى 234 من الأمهات اللاتي استكملن استبيانات حول إطعام أصغر أطفالهن سنا. وقد تناولت الاستبيانات العوامل التي تسهم في الترحيب باستمرار الرضاعة الطبيعية من الثدي، كما تضمنت تساؤلات حول العوامل التي أدت لاتخاذهن قراراً بإنهائها . واتضح للباحثين أن 26.5 % فقط من الأمهات قد واصلن الرضاعة الطييعية من الثدي لمدة وصلت أو تجاوزت ستة أشهر، وأن العوامل التي يعتد بها إحصائيا من حيث المساهمة في التأثير عل الإيقاف الباكر للرضاعة هي: السكن في مسكن منفصل عن بقينة الأسرة ،وارتفاع سن الأم، والبدء المتأخر بالرضاع من الثدي، وكون الأم موظفة مع عدم وجود تسهيلات للرضاعة الطبيعية من الثدي أثناء العمل، وتلقي معلومات حول الإرضاع الطبيعي من الثدي بعد الولادة وليس قبلها، ومرض الأم أو الرضيع. كام أن بعض الآباء كان عاملا يعتد به في تشجيع ممارسة الرضاعة الطبيعية من الثدي. واستنتج الباحثون ضرورة التوصية باستراتيجيات وقائية لتعزيز الرضاعة الطبيعية من الثدي، مع تأكيد خاص عل العوامل التي ترتبط بالإيقاف المبكر للرضاعة، تنفيذا للتوصيات التي أصدرتها متظمة الصحة العالمية في سياق الصحة العامة العالمية لإنجاح الإرضاع الطبيعي من الثدي في الكويت.
ABSTRACT To explore the possible determinants of duration of breastfeeding in Kuwait, 234 mothers completed a questionnaire concerning the feeding of their youngest infant. The questionnaire addressed the factors that contributed to their willingness to continue breastfeeding and enquired about the factors leading to their decision to end it. Only 26.5% of the mothers had continued breastfeeding for 6 months or more. Separate family housing, higher maternal age, late initiation of breastfeeding, being employed without the feasibility to breastfeed at work, breastfeeding information given after rather than before birth, and maternal and infant sickness were all significant contributors influencing early cessation. Father's support was a significant factor that encouraged the practice. In conclusion, preventive strategies are recommended for boosting breastfeeding, with special emphasis on the factors linked to early cessation, aiming at full implementation of the WHO global public health recommendations for successful breastfeeding in Kuwait.
Pratique de l'allaitement maternel au Koweït : déterminants de réussite et motifs d'échec
RÉSUMÉ Afin d'étudier les déterminants possibles de la durée de l'allaitement maternel au Koweït, 234 mères ont rempli un questionnaire sur l'alimentation de leur plus jeune enfant. Le questionnaire portait sur les facteurs contribuant à leur volonté de poursuivre l'allaitement et sur les facteurs qui les ont conduit à leur décision d'y mettre fin. Seules 26,5 % des mères ont allaité au sein pendant au moins 6 mois. Les facteurs contribuant significativement à un arrêt précoce de l'allaitement au sein étaient les suivants : une résidence familiale séparée, un âge maternel élevé, une initiative tardive de l'allaitement, un emploi sans possibilité d'allaiter sur le lieu de travail, une communication sur l'allaitement faite après la naissance plutôt qu'avant, et une affection chez la mère et/ou chez l'enfant. Le soutien du père était un facteur important qui favorisait la pratique de l'allaitement. En conclusion, des stratégies préventives sont recommandées afin de promouvoir l'allaitement au sein tout en prenant particulièrement en compte les facteurs liés à un arrêt précoce de l'allaitement, et de viser une mise en oeuvre intégrale des recommandations mondiales de l'OMS en santé publique pour la réussite de l'allaitement maternel au Koweït.
1Department of Paediatrics, Faculty of Medicine, Ain Shams University, Cairo, Egypt (Correspondence to M.F. Nassar:
Received: 06/11/13; accepted: 23/02/14
EMHJ, 2014, 20(7): 409-415
Introduction
Breastfeeding is an unequalled way of providing ideal food for the healthy growth and development of infants. As a global public health recommendation, infants should be exclusively breastfed for the first 6 months of life to achieve optimal growth, development and health. To meet their evolving nutritional requirements, infants should receive nutritionally adequate and safe complementary foods while breastfeeding continues for up to 2 years of age or beyond (l).
Although developed countries debate the World Health Organization's (WHO) recommendation of 6 months' exclusive breastfeeding (l), Morales et al. advised promotion of predominant breastfeeding for 4-6 months to reduce the burden of allergic manifestations and infections in infancy (2) . Earlier in 2001 Kramer et al. reported that increasing the duration and degree of breastfeeding decreased the risk of gastrointestinal tract infection and atopic eczema in the first year of life (3) . Recently, Nwaru et al. stated that longer duration of total breastfeeding, rather than its exclusivity, was protective against the development of non-atopic asthma (4).
Regarding the situation in Kuwait, Dashti et al. in 2010 reported a high rate of breastfeeding initiation (92.5% of their studied sample of mothers); however, at discharge from hospital, only 84.8% of participants were breastfeeding their infants, with less than one-third of mothers (29.8%) fully breastfeeding and only 10.5% exclusively breastfeeding (5). Earlier, Al-Bustan and Kholi studied a sample of 1553 Kuwaiti married women during 1985 and found that the proportion of children breastfeeding at 6 months ranged from 35% to 44% (6). This discrepancy between the percentage who initiate and those who continue, as well as the fact that there are no recent data concerning the duration of breastfeeding in Kuwait, inspired the design of the current study. Considering the low percentage of exclusive breastfeeding at hospital discharge in Kuwait, as reported by Dashti et al. (5), the current study was designed to examine the possible determinants of any breastfeeding during the first 6 months of life. Targeting those factors would help develop strategies for boosting the duration of breastfeeding and hence fulfil the goals set by WHO.
Methods
Study design and sample
This exploratory study included 280 women ofchildbearing age living in Kuwait. The study was conducted between December 2012 and June 2013 and included mothers seeking medical advice for their children in the outpatient clinics ofAl Adan Hospital. Al Adan Hospital is one ofthe biggest general governmental hospitals in Kuwait that offer medical health services to the population of Al Ahmadi region located south ofKuwait. Two paediatric clinics, attended weekly by the principal researcher, were used for recruiting Arab mothers to the study.
Data collection
A questionnaire based on that of the Infant Feeding Practices Study II by the Centers for Disease Control and Prevention (7) was translated to Arabic and back translated to English for verification by independent personnel. Finally, the Arabic form was pilot-tested on 20 randomly chosen mothers. The questionnaire was modified for better comprehension as perceived by the mothers. After obtaining their informed verbal consent, each eligible mother completed the questionnaire concerning the feeding history of their 2-3-year-old child. The questionnaire was administered by the researchers via a face-to-face interview, which had the advantage of ensuring that it was understood and fully completed. Only Arab mothers were targeted to ensure proper understanding of the questionnaire and to nullify the effect of culture and ethnic differences on breastfeeding. Mothers who refused to participate and those giving birth to premature babies with congenital malformations or needing neonatal intensive care (NICU) admission were excluded from the study.
The questionnaire included 3 sections. The first explored the sociodemo-graphic data of the mother and details about her infant's diet history. The second addressed the factors that might have contributed to her willingness to continue breastfeeding, and the last section enquired about the factors leading to her decision to end breastfeeding. The weight of each factor was requested as a 4-point Likert scale (not important, somewhat important, important, very important).
Data analysis
SPSS statistical package, version 20, was used for data analysis. Descriptive statistics were generated for demographic factors, the chi-squared test was used to compare categorical data and the f-test was used to compare continuous data. For assessment of factors associated with breastfeeding cessation at 6 months ofage we used multivariate Cox regression analyses. A total of 21 variables were included in the final model that was constructed using factors that had an association with breastfeeding duration based on the univariate association (the level of significance was set at P < 0.05), as well as factors reported to influence breastfeeding initiation and duration from previous studies (5,6,8-10) and that were considered to potentially affect breastfeeding practice in our local region.
The variables included in the multivariate Cox regression models were: mother's age (years), nationality (Kuwaiti, non-Kuwaiti), education (primary, secondary, university), residence (living within family home, separate housing), whether the mother had breastfed before (yes or no), when the mother started to breastfeed (hours), time of weaning (months), mothers' ability to breastfeed at work (not employed, employed and can or cannot breastfeed at work), time the mother received information regarding breastfeeding (during pregnancy, after birth), source of breastfeeding information (doctor, nurse, relatives and friends, the media), adequacy of milk production during the first week of breastfeeding as perceived by the mother (adequate, inadequate), child's birth order (1st, 2nd, 3rd, 4th, > 4th). The following variables were also included in the initial model, each assessed on a 4-point Likert scale (not important, somewhat important, important, very important): mother's perception of the effect of encouragement to continue breastfeeding from father, grandmother, doctor and treating team; mother's perception of the effect of her own illnesses or her baby's illness (if any) on continuation of breastfeeding; mother's perception of the fear that the baby was not growing well and its effect on continuation of breastfeeding; and mother's perception of the role of knowing breastfeeding benefits, having successful experiences with breastfeeding and the effect of domestic responsibilities on the duration of breastfeeding.
Results
The results ofthe current study revealed that out of 342 screened mothers 280 were eligible (i.e. their youngest child was 2-3 years old). Out of the 280 mothers 19 were excluded (4 refused and 15 had had their babies admitted to the NICU for prematurity or congenital malformations) and 27 (9.6%) had not initiated breastfeeding for their infants. Ofthe 234 enrolled women 62 (26.5%) had breastfed for > 6 months.
The demographic and social characteristics of the study sample are shown in Table 1, which also provides a comparison between mothers who had breastfed for < 6 months and those who had breastfed for > 6 months. It shows that mothers who had completed 6 months of breastfeeding initiated their breastfeeding earlier and their infants were weaned at a later age than the mothers who breastfed for < 6 months and this was a statistically significant difference (P < 0.001). Other factors that showed statistical significance were: nationality, level of education, feasibility of breastfeeding at work, timing of receiving breastfeeding information, and self-perceived adequacy of breastmilk.
Table 2 demonstrates factors influencing breastfeeding duration as perceived by the mothers. Among the causes of success only the father's encouragement reached statistical significance (P = 0.019). Regarding the reasons for failure only the mother's sickness reached statistical significance (P = 0.046).
Factors associated with termination of breastfeeding before 6 months in the regression analysis are summarized in Table 3. The data show that separate housing, higher maternal age, late initiation of breastfeeding, working without the feasibility of breastfeeding the infant at work, breastfeeding information given after rather than before birth, and maternal and infant sickness were all significant factors influencing early cessation of breastfeeding as reported by mothers. On the other hand, father's encouragement and support to continue breastfeeding was a significant factor that protected against early breastfeeding cessation.
Discussion
The initiation rate for breastfeeding in the current study was 90.4%, which is close to that reported by Dashti et al. in Kuwait (5) and Xu et al. in China (8). Higher initiation rates of 94%, 94.4% and 98% were reported among Saudi Arabian (9), Tunisian (ll) and Emirati mothers (10) respectively.
Only 26.5% of the enrolled women in the current study had breastfed for 6 months or more compared with 49.9% of Arab mothers in Qatar who continued breastfeeding at 1 year (12). Shawky and Abalkhail reported that 40% of their series of mothers who lived in Jeddah, Saudi Arabia, were breastfeeding at 1 year (9). Reports of breastfeeding practices vary greatly around the world. A Canadian study reported nearly a 100% initiation rate and 70% breastfeeding rate at 6 months (13), while another study, from Hong Kong, recorded an initiation rate of only 67% and by the 6th week only 26.7% of mothers were still breastfeeding (14). In western France, an area of low initiation, 25% of mothers were reported to breastfeed until 6 months (15).
The data of this study highlights that living separately from the rest of family, higher maternal age, later initiation of breastfeeding, no possibility of breastfeeding at work, breastfeeding information given after rather than before birth, maternal and infant sickness as well as absence offather's encouragement were all significant factors influencing early cessation of breastfeeding, as reported by mothers.
The partner's supporting influence and external encouragement for the lactating mother were highlighted in previous studies (14,16,17). Additionally, maternal illness was perceived by the studied mothers as an important cause of failure to breastfeed. Worth mentioning here is that misconceptions regarding breastfeeding are not uncommon. In Kuwait, Ibrahim et al. reported that 66%, 60% and 55% offemale university students thought mothers should temporarily stop breastfeeding if they had a fever, skin rash or sore throat respectively (18).
The current study reported that advanced maternal age was a risk factor for early cessation of breastfeeding. This is contrary to Al-Bustan and Kholi, who demonstrated a positive association between the duration of breastfeeding among Kuwaiti mothers and maternal age as well as parity, and a negative association with mother's level of education (6). This contradiction might be attributed to the inclusion of Arab non-Kuwaiti mothers in the present study which was not the case in the latter one, a finding which needs further consideration.
Similar to the results of the current study, Wang et al. found that the earlier the initiation ofbreastfeeding the longer the duration of breastfeeding (14). In addition, the present work suggested that breastfeeding information given before birth can boost rates of breastfeeding, and this agrees with Bouanene et al., who emphasized the importance of giving breastfeeding information before rather than after birth (11), and Wang et al., who highlighted the importance of mothers' intention to breastfeed in the success of the practice (14).
Being employed without having the feasibility to breastfeed at work was reported by our sample of mothers as an important determinant for cessation of breastfeeding. Bonet et al. reported that the sooner the mothers returned to work, the less likely they were breastfed their babies at 4 months of infant's age, independently of full-time or part-time employment (19). The authors further added that in a society where breastfeeding is not the norm, women may have difficulties combining work and breastfeeding, a situation which should not pose a problem in the Arab world, where breastfeeding is the norm.
Legislation in most Arab countries is derived from Islamic sharia law based on the Holy Quran and the Hadiths. The Quran says that the mothers shall give suck to their offspring for 2 complete years (20), which might give Arab mothers an advantage over mothers in other cultures. Nevertheless, the rate of mothers' breastfeeding for > 6 months recorded in the current study are still far below WHO recommendations.
The current work had its own limitations. The mothers were enrolled from one hospital, and only the clinics attended by the principle researcher were utilized for sample collection, which could have contributed to the small sample size, although this was done to minimize interviewer bias. Possible recall bias by the mothers was another limitation. An important limitation was that our definition of breastfeeding covered any type breastfeeding; future research enrolling a large number of exclusively breastfed infants might show significant associations specific to this category. Nonetheless, the current work addressed the low rate of breastfeeding in this part of the world and highlighted important factors that can be specifically modified to enhance the practice.
In conclusion, breastfeeding practice in Kuwait showed a good rate of initiation yet a poor rate of continuation. The common causes for failure to proceed in breastfeeding were separate family housing, higher maternal age, late initiation of breastfeeding, being employed without having the feasibility to breastfeed at work, breastfeeding information given after rather than before birth, and maternal and infant sickness. Preventive strategies are needed for boosting breastfeeding in Kuwait with special emphasis on these points with the aim of full implementation of the WHO global public health recommendations for exclusive breastfeeding.
References
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- Al Bustan M, Kohli BR. Socio-economic and demographic factors influencing breast-feeding among Kuwaiti women. Genus. 1988 Jan-Jun;44(1-2):265-78. PMID:12281668
- Infant Feeding Practices Study II. Project FIRST infant month 2 questionnaire. Global opinion panels [Internet]. Atlanta (GA): Centers for Disease Control and Prevention; 2007 (http:// www.cdc.gov/ifps/pdfs/IFPS_II/month2/Month2GOP.pdf, accessed 19 April 2014).
- Xu F, Binns C, Yu P, Bai Y. Determinants of breastfeeding initiation in Xinjiang, PR China, 2003-2004. Acta Paediatr. 2007 Feb;96(2):257-60. PMID:17429916
- Shawky S, Abalkhail BA. Maternal factors associated with the duration of breast feeding in Jeddah, Saudi Arabia. Paediatr Perinat Epidemiol. 2003 Jan;17(1):91-6. PMID:12562476
- Radwan H. Patterns and determinants of breastfeeding and complementary feeding practices of Emirati Mothers in the United Arab Emirates. BMC Public Health. 2013, 13:171 doi:10.1186/1471-2458-13-171.
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Dietary habits and physical activity levels in Jordanian adolescents attending private versus public schools
R.F. Tayyem,1 H.M. AL-Hazzaa,2 S.S. Abu-Mweis,1 H.A. Bawadi,3 S.S. Hammad1 and A.O. Musaiger4
العادات الغذائية ومستوى النشاط البدني بين المراهقين الأردنيين الملتحقين بالمدارس الخاصة مقابل المدارس العامة
ريما تيم، هزاع الهزاع، سهاذ أبو مويس، هبة بوادي، شذى حماد، عبد الرحمن المصيقر.
الخلاصة: تتناول هذه الدراسة الفوارق في العادات الغذائية ومستوى النشاط البدني بين التلاميذ في المرحلة الثانوية في المدارس الخاصة وفي المدارس العامة في الأردن. وقد شملت الدراسة 386 طالباً و349 طالبة في المرحلة الثانوية تتراوح أعمارهم بين 14 و18 عاما، وتم إدراجهم في الدراسة عشوائياً باستخدام تقنية أخذ العينات العنقودية المطبقة والمتعددة المراحل. وتم الإبلاغ ذاتيا عن العادات الغذائية ومستوى النشاط البدني باستخدام استبيان تم التحقق من صحته. واتضح أن معدل انتشار البدانة أعلى بمقدار يعتد به إحصائيا بين المراهقين في الدارس الخاصة (26.0%) مما هو عليه في الدارس العامة (16.7%). وأن تكرار تناول طعام الإفطار هو أعلى بمقدار يعتد به إحصائيا بين المراهقين في الدارس الخاصة، بينما معدل تناول البطاطس المقلية والحلويات أعلى بمقدار يعتد به إحصائيا لدى المدارس العامة. كما اتضح أن مشاهدة التلفزيون تؤدي إلى تفاعل ذي أهمية إحصائية مع نمط المدرسة والجنسين. واتضح وجود مستوى أعلى من الخمول البدني بين طلاب المدارس الخاصة. ورغم أن المرتسم الإجمالي للتظام الغذائي لدى طلاب المدارس الخاصة يبدو أفضل قليلا مما هو عليه في سواها، فإن لدى هؤلاء نسبة أعل من فرط الوزن والبدانة مقارنة بطلاب المدارس العامة.
ABSTRACT The present study examined differences in dietary habits and physical activity levels between students attending private and public high schools in Jordan. A total of 386 secondary-school males and 349 females aged 14-18 years were randomly recruited using a multistage, stratified, cluster sampling technique. Dietary habits and physical activity level were self-reported in a validated questionnaire. The prevalence of obesity was significantly higher among adolescents in private (26.0%) than in public schools (16.7%). The frequency of breakfast intake was significantly higher among adolescents in private schools, whereas French fries and sweets intake was significantly higher in public schools. Television viewing showed a significant interaction with school type by sex. A higher rate of inactivity was found among students attending private schools. Despite a slightly better overall dietary profile for students in private schools, they had a higher rate of overweight and obesity compared with those in public schools.
Habitudes alimentaires et niveau d'activité physique chez les adolescents jordaniens fréquentant une école privée par rapport à ceux fréquentant une école publique
RÉSUMÉ La présente étude a examiné les différences dans les habitudes alimentaires et les niveaux d'activité physique entre les élèves des écoles publiques et ceux des écoles privées en Jordanie. Au total, 386 garçons et 349 filles fréquentant des établissements d'enseignement secondaires âgés de 14 à 18 ans ont été recrutés aléatoirement au moyen d'une technique d'échantillonnage en grappes, stratifié à plusieurs degrés. Les habitudes alimentaires et le niveau d'activité physique ont été autodéclarés à l'aide d'un questionnaire validé. La prévalence de l'obésité était significativement plus élevée chez les adolescents des écoles privées (26,0 %) que chez ceux des écoles publiques (16,7 %). La prise d'un petit-déjeuner était nettement plus fréquente chez les adolescents des écoles privées, tandis que la consommation de frites et de sucreries était beaucoup plus importante chez les élèves des écoles publiques. Le nombre d'heures passées à regarder la télévision était très différent entre les élèves des écoles privées et ceux des écoles publiques en fonction du sexe. Un taux d'inactivité plus élevé a été observé chez les élèves des écoles privées. En dépit du profil diététique légèrement meilleur des élèves des écoles privées, leurs taux de surpoids et d'obésité étaient supérieurs à ceux des écoles publiques.
1Department of Clinical Nutrition and Dietetics, The Hashemite University, Zarqa, Jordan (Correspondence to R.F. Tayyem:
2Pediatric Exercise Physiology Research Laboratory, College of Education, King Saud University, Riyadh, Saudi Arabia.
3Department of Nutrition and Food Technology, Jordan University of Science and Technology, Irbid, Jordan.
4Arab Center for Nutrition, Manama, Bahrain, and Nutrition and Health Studies Unit, Deanship of Scientific Research, University of Bahrain, Sakheer, Bahrain.
Received: 11/07/13; accepted: 04/02/14
EMHJ, 2014, 20(7):416-423
Introduction
Studies in Arab countries have shown a high prevalence of overweight and obesity among adolescents, with rates ranging from 25% to 60% (l). The prevalence of overweight among Jordanian male and female adolescents was found to be 21.6% and 17.5% respectively (2). Poor eating habits and physical inactivity are the most important risk factors for obesity and other chronic diseases (3). Dietary and lifestyle behaviours of adolescents in the Middle Eastern countries have changed dramatically during the past 2 decades (l). Studies in several Arab countries have shown that the food habits of adolescents are characterized by high intakes of food rich in fat and calories, as well as in salt and sugar. In Saudi Arabia for example, Al-Hazzaa et al. found that about two-thirds of Saudi adolescents consumed sugar-sweetened drinks more than 3 times a week, and about a third of them consumed fast food more than 3 times a week (4). In Bahrain, half of the adolescents do not eat breakfast daily, and about third ofthem rarely ate fruits and/ or vegetables (5). Furthermore, inactivity and a sedentary lifestyle have become widespread among adolescents in this region. For example, about -third of Bahraini adolescents watched television for more than 5 hours a day, and about 69% of males practised sports everyday compared with 31% of females (5).
Few studies have correlated obesity, dietary habits and lifestyles of children and adolescents with socioeconomic status (SES) in developing countries (6-8). Although not the most commonly used indicator, school type (private versus public) can be a proxy for SES because the majority of students enrolled in private schools come from moderate- to high-income families (6,7). The prevalence of unhealthy weight, undesirable dietary patterns, sedentary behaviours and physical inactivity has been found to be markedly higher in private than public schools in many countries. A study by Chakar and Salameh showed that the prevalence of obesity and overweight was 7.5% and 24.4% respectively among Lebanese adolescent attending private schools (6). They attributed this to the higher SES of pupils at private schools, which could allow a greater adoption of unhealthy nutritional habits (fast food, energy-dense snacks, sweets, etc.) (6). In Sana'a city, Yemen, overweight and obesity had a significantly higher prevalence among children attending private schools (7). Another study, in Pakistan, found that the prevalence of overweight (including obesity) was significantly higher among private schoolboys (9). However, Al-Nuaim et al. reported that Saudi female adolescents who attended public schools were more active than those who attended private schools (10).
The aim of this study was to investigate the differences in anthropometric measurements, dietary habits and lifestyle factors between students attending private and public schools in Jordan. To the researchers' knowledge this is the first study of its kind in Jordan.
Methods
Sample
The present study is part of the Arab Teens Lifestyle Study (ATLS), which is a pan-Arab, school-based, multi-centre collaborative project conducted between October and December of 2009 (ll). The study protocol and procedures were approved by the ethics committee of the Jordanian Ministry of Education.
The participants were adolescent males and females selected from grades 10, 11 and 12 of 8 secondary schools in the capital of Jordan, Amman. The minimum sample size was determined so that the sample proportion would be within ± 0.05 of the population proportion with a 95% confidence level. The population proportion was assumed to be 0.50, as this magnitude yield the maximum possible sample size required.
To gather the required sample, a multistage, stratified, cluster random sampling technique was used. In the first stage, a systematic, random sampling procedure was used to select the schools. The schools were stratified into boys' and girls' secondary schools, with further stratification into public and private schools. Four large public schools as well as 4 private schools were selected. Girls and boys were selected from 2 private and 2 public schools. The selection of private and public schools was proportional to population size. All students in the selected classes who were free from any physical deformity were invited to participate in the study. A formal letter from the Ministry of Education was directed to the schools to facilitate completing the validated questionnaire. All the schools and students were formally consented to be involved in the survey. The final sample size consisted of 735 adolescents (386 males and 349 females; 353 students from public schools 382 from private schools).
Data collection
Anthropometric measurements
Body weight was measured with students wearing minimal clothing and without shoes and to the nearest 100 g using a calibrated portable scale. Height was measured in the full standing position without shoes and to the nearest 0.1 cm using a calibrated portable measuring rod. Body mass index (BMI) was calculated as the ratio of weight (kg) to the square of height (m). The International Obesity Task Force age-and sex-specific BMI reference values were used to define overweight and obesity in adolescents aged 14-17 years (l2). For participants aged 18 years, we used the cut-off points for adults (overweight 25-29.9 kg/m2; obesity > 30 kg/m2). Waist circumference (WC) was measured horizontally to the nearest centimetre using a non-stretchable measuring tape at the level ofthe umbilical and after gentle expiration. Waist to height ratio (WHtR) was calculated as the ratio between WC in cm and height in cm.
Assessment of lifestyle factors
Lifestyle factors were assessed by a validated, self-reported questionnaire and included physical activity, sedentary behaviours and dietary habits (11,13,14). The ATLS research instrument was used for the assessment of lifestyle factors. The participants completed the ATLS questionnaire in their classrooms under the supervision of their teachers and the research assistants. The physical activity questionnaire collects self-reported data on the frequency, duration and intensity of light, moderate and vigorous intensity physical activities during a typical (usual) week. The physical activity questionnaire has been shown to have a high reliability and acceptable validity against pedometer-assessed activity in females and males aged 14-19 years (11,15).
The physical activity questionnaire covers several domains, including transport, household, fitness and sporting activities. Physical activities were assigned metabolic-equivalent (MET) values based on the compendium of physical activity (16) and the compendium of physical activity for youth (17).
Moderate intensity physical activities include activities with values of 3-6 METs, such as normal pace walking, brisk walking, recreational swimming, household activities and recreational sports such as volleyball, badminton and table tennis. Vigorous intensity physical activities and sports included activities with values > 6 MET, such as stair climbing, jogging, running, cycling, self-defence, weight training, soccer, basketball, handball and singles tennis. For physical activity cut-off values, we used 60 minutes of daily moderate-intensity physical activity. The sedentary behaviours included questions related to typical daily time in hours spent viewing television (TV) and/or video, playing computer games or using a computer and the Internet. Total screen time was classified as > 5 hours per day, 3-4 hours per day and < 2 hours per day.
Questions dealing with dietary habits included some healthy and unhealthy dietary habits and were related to how many times per week the participant consumed breakfast, vegetables (cooked and uncooked), fruit, milk and dairy products, sugar-sweetened beverages (including soft drinks), doughnuts/cakes, sweets and chocolates, energy drinks and fast foods. The student has a choice ofanswers, ranging from 0 intake (never) to a maximum intake of 7 days per week (every day).
Dietary habits were categorized into 3 levels of intake: > 5 days/week, 3-4 days/week and < 3 days/week.
Data analysis
The data were analysed using SPSS, version 15. Questionnaires with missing responses were excluded. The data were examined for any clustering effect, but there was no evidence of data clustering in the sample, as intra-class correlation coefficients were very low (averaging 0.016) and were insignificant (P = 0.377). Descriptive statistics are presented as means and standard error of the mean (SE) or proportions. Multivariate analysis of covariance (MANCOVA) was also used, while controlling for the effects of age, to test for differences in lifestyle variables across sex (males and females) and school type (public and private). The chi-squared test was used to find the significance between private and public schools in the non-continuous (proportions) parameters. The level of significance was set at P < 0.05.
Results
Table 1 shows the demographic characteristics and anthropometric measurements ofthe students. Adolescents from private schools in the 3 sampled school grades were significantly (P < 0.001) younger [15.8 (SE 0.86) years] than their counterparts from public schools [16.6 (SE 0.95) years]. A significantly higher mean body weight (P < 0.003) and BMI (P < 0.038) was recorded in students attending private schools. The combined prevalence of obesity and overweight was significantly higher in students from private schools (26.0%) compared with those in public schools (16.7%) (P < 0.005).
For the dietary intake study 52 questionnaires from public and 9 from private schools were excluded due to missing answers. Frequency of intake of breakfast, sweets and French fries per week showed a significant difference between the 2 types of schools (Table 2). Frequency of breakfast intake per week was higher among the private school-students, while sweets and French fries intake was higher among public school-students.
The results of dietary habits among studied Jordanian adolescents relative to school type and sex, while controlling for the effect of age, are shown in Table 3. There were significant differences between the sexes by type of school in relation to weekly intakes of fast food and sweets (P < 0.05). Boys and girls had significantly different weekly rates of consumption of most of the foods assessed in the study (breakfast, fruits, milk, sugar-sweetened drinks, fast food, sweets French fries, and cake/ doughnuts) (P < 0.05). Compared with students in private schools, students in public schools reported significantly higher intakes ofsweets and French fries (P < 0.05) and lower intake of breakfast (p < 0.05). Table 4 shows the MANCOVA results for sedentary behaviours, sleep duration and physical activity levels among the Jordanian adolescents relative to school type and sex. Only TV viewing showed a significant difference with school type by sex interaction effect (P < 0.05). In addition, boys and girls showed significant differences in the reported rates of vigorous intensity and total physical activity, while age had a significant effect on TV viewing, computer use and moderate intensity physical activity (P < 0.05).
The proportions of Jordanian adolescents who exceeded certain cut-off values for screen time, physical inactivity and selected dietary habits relative to school type are shown in Table 5. Higher rates of inactivity were found among students attending private schools, whereas adolescents in public schools were significantly more likely to exceed 3 days per week intake of sweets/chocolates and French fries/ potato chips (P < 0.05).
Discussion
The present study found a significant difference in the prevalence of obesity among adolescents in private schools (26.0%) than those in public ones (16.7%). The frequency of French fries and sweets intake was significantly higher in public schools. On the other hand, breakfast intake was significantly higher among adolescents in private schools. The other dietary habits, sleep duration and physical activity levels was similar in both school types.
Similar results of the combined prevalence of overweight and obesity in students attending public and private schools had been shown by Raja'a and Bin Mohanna (7). They reported that the prevalence of obesity and overweight was 6.5% and 23.7% in Yamani public and private schools respectively. Our findings also agree with the results of another study, conducted on Pakistani schoolchildren, which reported overweight prevalence rates of 24.0% and 8.7% in private and public schools respectively (9). Moreover, the prevalence of combined overweight and obesity was shown to be markedly higher in private schools (boys: 37%; girls: 33%) than in public schools (boys: 33%; girls: 20%) schools in the Seychelles (18).
The current study revealed that there were significant interactions ofsex and school type with the frequencies of fast food and sweets intake. Males but not females in private schools were consuming fast foods more frequently per week than were males in public schools. It has been documented that regular consumption of breakfast provides some protection against weight gain (19). However, in the present study, students from private schools were reporting more frequent intake of breakfast, yet they had a higher percentage of overweight and obesity than students in public schools. This discrepancy can be explained by the fact that not all studies have associated skipping breakfast with overweight (20). In addition, the type of breakfast can also make a difference. A study by Deshmukh-Taskar et al. reported that the prevalence of obesity was higher among children and adolescents skipping breakfast than in those consuming ready-to-eat cereals and it was higher among adolescents eating breakfast other than ready-to-eat cereals (21). In addition, higher BMI in private schools could be attributed to the higher total calorie intake among students in private schools (21). However, in the current study no assessment of total energy intake was done.
Females but not males in the public schools reported more frequent intake of sweets compared with females from private schools. In addition, no significant differences in the frequencies of intake of vegetables, fruit, milk, fast foods, sugar-sweetened and energy drinks were detected between students of private and public schools. However, a higher intake of fast foods, soft drinks, fruit juices, fruit, sweets and chips was demonstrated in students of private schools than in government schools in Qureshi et al.'s study (9). Although no significant difference in sedentary behaviours, sleep duration or physical activity levels were detected relative to school type in the present study, the METs-min/week of total physical activity and vigorous physical activity were found to be higher among male students in public than in private schools (9). The lower level of physical activity in females has generally been acknowledged across different cultures (6,22,23). Even though higher intake of French fries and sweets was reported by students in public schools, the higher intake of fast foods and lower (but not significant) total METs-min/week of activity were found in students attending private schools. This could partially explain the higher prevalence of obesity and overweight among students attending private schools.
Another explanation is the higher SES in students attending private schools. Most of the available studies assessed the association between obesity in children and SES (low or middle income) in developing countries rather than depending on type of school. The validity of using attendance of private school or public school as an indicator of SES may vary from one population to another. Many families of high SES also attend public schools. Furthermore, students in public schools do not occupy a specific SES category but, instead, they represent largely different socioeconomic positions, from highest to lowest, with the majority of them coming from the lowest SES. However, the situation in Jordan is different. In Jordan, attending private or public schools is highly associated with SES (24,25). Also, Qureshi et al. showed that the higher food intake among students attending private schools may be because they receive more pocket money than government schoolboys (9).
Limitations of the study
A valid and reliable questionnaire was used to obtain collect data from the students. However, the data were self-reported and were therefore dependent upon the students' recall. The part of the questionnaire concerning dietary habits was qualitative and no portion sizes were evaluated. No total energy intake was measured, which may be a confounding factor. Furthermore, the present study was of a cross-sectional design and therefore the direction of causality cannot be assumed. Also, the SES was not assessed, since most of the students did not know their family's exact monthly income. However, the information provided by the present study adds to the limited existing data on lifestyle and dietary habits of Jordanian adolescents attending private and public schools.
Conclusion
A higher prevalence of overweight and obesity was found among students attending private schools as compared with students in public schools. The frequency of breakfast intake was significantly higher in private schools, whereas more frequent intakes of French fries and sweets were reported among adolescents attending public schools. /Although the levels ofphysical activity were similar among students of both schools, females in general showed much lower physical activity compared with males. Promoting physical activity and health eating among Jordanian adolescents is recommended. Future research should examine the environmental and socioeconomic factors associated with obesity and lifestyle among adolescents in both types of schools.
Implications of the study
Physical inactivity and unhealthy dietary habits are known to be associated with body weight gain and poor health status of children and adolescents. In addition, studies have shown that children and adolescents who are physically active and consume healthy foods are less likely to be affected by type 2 diabetes, hypertension and abnormal lipid profile. The findings of the present study show that private as well as public schools need to pay more attention to adolescents' health behaviours. Our results highlight the need for educational programmes across the country to emphasize the importance of changing unhealthy behaviours and adopting healthy behaviours for life.
Acknowledgement
Funding: The authors would like to thank the Hashemite University for funding this research. Competing interests: None declared.
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