Cardiovascular disease (CVD) frequently has roots in childhood, including following childhood-onset hypertension. Incidence of CVD has increased in developing countries in East Africa during recent urbanization. Effects of these shifts on childhood hypertension are unclear. Our objectives were to (1) Determine the prevalence of hypertension among primary schoolchildren in Khartoum, Sudan; (2) Determine whether hypertension in this setting is associated with obesity. We performed a cross sectional study of 6-12y children from two schools randomly selected in Khartoum, Sudan. Height, weight, BMI, BP and family history of hypertension were assessed. Age-, height- and gender-specific BP curves were used to determine pre-hypertension (90–95%) and hypertension (>95%). Of 304 children, 45 (14.8%) were overweight; 32 (10.5%) were obese; 15 (4.9%) were pre-hypertensive and 15 (4.9%) were hypertensive. Obesity but not family history of hypertension was associated with current hypertension. In multiple logistic regression, adjusting for family history, children who were obese had a relative-risk of 14.7 (CI 2.45-88.2) for systolic hypertension compared to normal-weight children. We conclude that overweight and obesity are highly prevalent among primary schoolchildren in urban Sudan and are strongly associated with hypertension. That obesity-associated cardiovascular sequelae exist in the developing world at young ages may be a harbinger of future CVD in sub-Saharan Africa. 1. Introduction The prevalence of childhood obesity has been increasing at unsettling rates across the globe [1]. In addition to striking the developed world, this pattern has also been noted in developing countries undergoing rapid epidemiological transitions, including those in East Africa [2]. In Sudan, a study of children in secondary school in the capital Khartoum found that rates of overweight and obesity were 28.5% and 5.6%, respectively [3]. Rates of obesity for younger schoolchildren in East Africa remain unclear, though obesity at younger ages may carry greater importance because younger children possess improved potential for early intervention [4]. Hypertension, a notable sequela of obesity, was already common in sub-Saharan Africa [5] but has been reported to be worsening in prevalence in recent years [6]. Hypertension often goes underdiagnosed in children, in part because its accurate diagnosis requires the use of standardized growth charts specific for age, gender, and height, with hypertension defined as a systolic and/or diastolic blood pressure > 95th percentile and
References
[1]
A. M. G. Cali and S. Caprio, “Obesity in children and adolescents,” Journal of Clinical Endocrinology and Metabolism, vol. 93, no. 11, pp. s31–s36, 2008.
[2]
R. Belue, T. A. Okoror, J. Iwelunmor, et al., “An overview of cardiovascular risk factor burden in sub-Saharan African countries: a socio-cultural perspective,” Global Health, vol. 5, p. 10, 2009.
[3]
O. A. Salih and E. AbdelAziz, “Underweight, overweight and obesity among Sudanese secondary school children of Khartoum State,” Ahfad Journal, pp. 38–46, 2007.
[4]
M. Dehghan, N. Akhtar-Danesh, and A. T. Merchant, “Childhood obesity, prevalence and prevention,” Nutrition Journal, vol. 4, 2005.
[5]
J. Addo, L. Smeeth, and D. A. Leon, “Hypertension in sub-Saharan Africa: a systematic review,” Hypertension, vol. 50, no. 6, pp. 1012–1018, 2007.
[6]
Y. K. Seedat, “Recommendations for hypertension in sub-Saharan Africa,” Cardiovascular Journal of South Africa, vol. 15, no. 4, pp. 157–158, 2004.
[7]
H. C. McGill, C. A. McMahan, and S. S. Gidding, “Are pediatricians responsible for prevention of adult cardiovascular disease?” Nature Clinical Practice Cardiovascular Medicine, vol. 6, no. 1, pp. 10–11, 2009.
[8]
S. E. Barlow and W. H. Dietz, “Obesity evaluation and treatment: expert Committee recommendations. The Maternal and Child Health Bureau, Health Resources and Services Administration and the Department of Health and Human Services,” Pediatrics, vol. 102, no. 3, p. E29, 1998.
[9]
D. S. Freedman and B. Sherry, “The validity of BMI as an indicator of body fatness and risk among children,” Pediatrics, vol. 124, no. 1, pp. S23–S34, 2009.
[10]
C. L. Ogden, “Defining overweight in children using growth charts,” Maryland Medicine, vol. 5, no. 3, pp. 19–21, 2004.
[11]
B. Falkner, S. R. Daniels, J. T. Flynn et al., “The fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents,” Pediatrics, vol. 114, no. 2, pp. 555–576, 2004.
[12]
K. D. Monyeki, H. C. G. Kemper, and P. J. Makgae, “The association of fat patterning with blood pressure in rural South African children: the Ellisras Longitudinal Growth and Health Study,” International Journal of Epidemiology, vol. 35, no. 1, pp. 114–120, 2006.
[13]
H. H. Vorster, “The emergence of cardiovascular disease during urbanisation of Africans,” Public Health Nutrition, vol. 5, no. 1 A, pp. 239–243, 2002.
[14]
J. Mi, H. Cheng, D. Q. Hou, J. L. Duan, H. H. Teng, and Y. F. Wang, “Prevalence of overweight and obesity among children and adolescents in Beijing in 2004,” Zhonghua Liu Xing Bing Xue Za Zhi, vol. 27, no. 6, pp. 469–474, 2006.
[15]
S. Aziz, W. Noorulain, U. E. R. Zaidi, K. Hossain, and I. A. Siddiqui, “Prevalence of overweight and obesity among children and adolescents of affluent schools in Karachi,” Journal of the Pakistan Medical Association, vol. 59, no. 1, pp. 35–38, 2009.
[16]
R. Kelishadi, G. Ardalan, R. Gheiratmand et al., “Thinness, overweight and obesity in a national sample of Iranian children and adolescents: CASPIAN Study,” Child: Care, Health and Development, vol. 34, no. 1, pp. 44–54, 2008.
[17]
R. M. Lauer, L. A. Barness, R. Clark et al., “National Cholesterol Education Program (NCEP): highlights of the report of the expert panel on blood cholesterol levels in children and adolescents,” Pediatrics, vol. 89, no. 3, pp. 495–501, 1992.
[18]
R. V. Luepker, D. R. Jacobs, R. J. Prineas, and A. R. Sinaiko, “Secular trends of blood pressure and body size in a multi-ethnic adolescent population: 1986 to 1996,” Journal of Pediatrics, vol. 134, no. 6, pp. 668–674, 1999.
[19]
J. T. Flynn, “Pediatric hypertension: recent trends and accomplishments, future challenges,” American Journal of Hypertension, vol. 21, no. 6, pp. 605–612, 2008.
[20]
C. Agyemang, W. K. Redekop, E. Owusu-Dabo, and M. A. Bruijnzeels, “Blood pressure patterns in rural, semi-urban and urban children in the Ashanti region of Ghana, West Africa,” BMC Public Health, vol. 5, article 114, 2005.
[21]
W. E. Moore, J. E. Eichner, E. M. Cohn, D. M. Thompson, C. E. Kobza, and K. E. Abbott, “Blood pressure screening of school children in a multiracial school district: the healthy kids project,” American Journal of Hypertension, vol. 22, no. 4, pp. 351–356, 2009.
[22]
A. Chiolero, F. Cachat, M. Burnier, F. Paccaud, and P. Bovet, “Prevalence of hypertension in schoolchildren based on repeated measurements and association with overweight,” Journal of Hypertension, vol. 25, no. 11, pp. 2209–2217, 2007.
[23]
S. R. Daniels, P. R. Khoury, and J. A. Morrison, “The utility of body mass index as a measure of body fatness in children and adolescents: differences by race and gender,” Pediatrics, vol. 99, no. 6, pp. 804–807, 1997.
[24]
K. L. McNiece, T. S. Poffenbarger, J. L. Turner, K. D. Franco, J. M. Sorof, and R. J. Portman, “Prevalence of hypertension and pre-hypertension among adolescents,” Journal of Pediatrics, vol. 150, no. 6, article e1, pp. 640–644, 2007.
[25]
J. M. Sorof, D. Lai, J. Turner, T. Poffenbarger, and R. J. Portman, “Overweight, ethnicity, and the prevalence of hypertension in school-aged children,” Pediatrics, vol. 113, no. 3 I, pp. 475–482, 2004.