The objectives of this study are to investigate the developmental stages of hypertension between males and females and identify why young males have higher blood pressure than young females.Design and Method:
The study used a sub-sample of 2000 offspring from the original cohort of the Mater University of Queensland Study of Pregnancy (MUSP) and its outcomes. The MUSP is a prospective birth cohort study which commenced in early 1980 s in Brisbane, Australia and followed their offspring till young adulthood. Anthropometric and blood pressure data were measured at 5, 14, 21 and 30 year; and socio-economic, obstetric history and lifestyle of mothers were prospectively collected around pregnancy and offspring characteristics were prospectively collected at childhood, adolescent and young adulthood. Multivariable analyses were conducted to determine the developmental stages and differential impact of males and females were investigated.Results:
Maternal pregnancy exposures including obesity and hypertensive disorder in pregnancy and offspring growth trajectories prospectively associated with offspring blood pressure development at age 5 and 14 years. Although mean difference of systolic (SBP) and diastolic blood pressure (SBP) were not considerable at age 5 and 14 between males and females but by age 21 it was substantial (e.g. over 10 unit in SBS and 4 units in DBP). The prevalence of hypertension was much higher among males than females by age 21 year. None of the confounding or mediating factors, including maternal blood pressure, parental obesity, socioeconomic status, offspring physical inactivity and diets did not explain this substantial blood pressure difference between young males and females.Conclusions:
This study shows that maternal pregnancy exposures and offspring early growth trajectories prospectively associated the development of childhood and adolescent blood pressure. Blood pressure difference between males and females are substantial and it mainly exhibits from adolescent to young adulthood. Mechanisms behind this will be discussed.