The impact of genetic and environmental influences on blood pressure variance across age-groups

Objective The purpose of the present investigation was to examine the age-d ependency of blood pressure heritability by use of the twin method in diffe rent age groups. Design In 272 (150 monozygous and 122 dizygous) twin pairs, aged 18 to 76 y ears, both conventional and ambulatory blood pressure were measured. After correction for possible confounders, model fitting was used to estimate her itability and 95% confidence limits in three age groups of similar size, i, e, 18-29, 30-39 and greater than or equal to 40 years. Results Heritability estimates were significant in each age group, ranging from 35 to 67% for the various blood pressure measurements. The estimates t ended to decrease with increasing age, except for conventional diastolic bl ood pressure, but the intergroup differences did not reach statistical sign ificance, despite adequate power, Conclusions In conclusion, blood pressure heritability is significant in va rious age groups, but does not substantially change with advancing age. Twi n analysis does not indicate that models for blood pressure regulation in v arious age groups should take into account the possibility of age-related c hanges in the expression of relevant genes, in the presence of relevant env ironmental agents, or in the susceptibility to the latter (gene-environment interaction).