Background: Studies suggest that sex differences in blood pressure (BP) are established early in life. Sex differences in BP increases that occur during adolescence may be due to differences in changes in anthropometric characteristics.
Methods: Using sex-specific individual growth models, we assessed the effect of height, body mass index (BMI; kg/m2), waist circumference, and triceps and subscapular skinfold thickness on changes in systolic BP in a cohort of 1293 adolescents in Montreal, Canada. BP and anthropometry were assessed biannually (1999/2000, 2002, 2004) at mean ages 12.8, 15.2, and 17.0.
Results: On average, systolic BP increased by 11.1 mm Hg in boys and 3.2 mm Hg in girls during 5 years. Changes in height explained half of the overall increase in systolic BP in boys and virtually all of the increase in systolic BP in girls. No meaningful sex differences were observed in the association of changes in BMI, waist circumference, and triceps and subscapular skinfold thickness with systolic BP change during 5 years. Increases in 1 BMI unit, 1 cm waist circumference, or 1 mm triceps or subscapular skinfold thickness were associated with increases of 0.7, 0.24, 0.3, and 0.4 mm Hg systolic BP, respectively.
Conclusions: Although sex differences in mean systolic BP changes during adolescence were largely attributable to differences in gains in height, the effect of gaining weight or body fat on systolic BP change was similar in boys and girls.
From the aDepartment of Public Health Sciences, University of Alberta, Edmonton, Alberta, Canada; bDepartment of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada; cDepartment of Social and Preventive Medicine, Université de Montréal, Montreal, Quebec, Canada; dCentre de recherche de Centre hospitalier de l'Université de Montréal, Montreal, Quebec, Canada; eMcGill University Health Centre Research Institute, Montreal, Quebec, Canada; and fSchool of Health Sciences, University of South Australia, Adelaide, South Australia.
Submitted 30 April 2009; accepted 20 October 2009; posted 9 March 2010.
The NDIT study was supported by the National Cancer Institute of Canada with funds from the Canadian Cancer Society. This study was also supported by: a Doctoral Fellowship from the Canadian Institutes of Health Research (CIHR) and Strategic Training Fellowship in Transdisciplinary Public and Population Health Research from the CIHR & Quebec Population Health Research Network (to K.M.); a Canada Research Chair in Population Health from 2005 to 2008 (to J.L.): a Canada Research Chair in Early Determinants of Adult Chronic Disease (to J.OL.); and a CIHR Chair in Applied Public Health Research (to G.P.).
Jennifer O'Loughlin holds a Canada Research Chair in Early Determinants of Adult Chronic Disease, and Gilles Paradis holds a CIHR Chair in Applied Public Health Research.
Supplemental digital content is available through direct URL citations in the HTML and PDF versions of this article (www.epidem.com).
Correspondence: Katerina Maximova, Department of Public Health Sciences, School of Public Health, University of Alberta, 3-20D University Terrace, 8303-112 St, Edmonton, AB T6G 2T4 Canada. E-mail: email@example.com.