Maternal Age of Menarche and Blood Pressure in Adolescence: Evidence from Hong Kong's "Children of 1997" Birth Cohort

Background Age of puberty has declined substantially in developed settings and is now declining in the rest of the world with economic development. Early age of puberty is associated with non-communicable diseases in adulthood, and may be a long-term driver of population health with effects over generations. In a non-Western setting, we examined the association of maternal age of menarche with blood pressure in late childhood/adolescence. Methods We used generalised estimating equations to estimate the adjusted association of maternal age of menarche with age-, sex-and height-adjusted blood pressure z-score from 10 to 16 years in Hong Kong's population-representative birth cohort, "Children of 1997" (n = 8327). We also assessed whether associations were mediated by body mass index (BMI) or pubertal stage. Results Earlier maternal age of menarche was associated with higher systolic blood pressure in adolescence [-0.02 z-score per year older maternal age of menarche, 95% confidence interval (CI) -0.04 to -0.003]. The association of maternal age of menarche with systolic blood pressure was mediated by adiposity and/or pubertal stage at 11 years. Maternal age of menarche was not associated with diastolic blood pressure. Conclusion Earlier maternal age of puberty was associated with higher systolic blood pressure, largely mediated by adiposity, highlighting the importance of tackling childhood obesity as a public health priority in view of the secular trend of declining age of puberty.