Blood pressure changes with aging: evidence for a cohort effect.

Data from cross-sectional surveys show an increase in systolic blood pressure with increasing age. However, cross-sectional data can be misleading. Our purpose in this study is to prospectively describe changes in systolic and diastolic blood pressure levels over time in community-dwelling elderly persons. The participants were 1,917 men and women aged 65 to 98 yr who had participated at least seven years in the Florida Geriatric Research Program, a community-based, multi-phasic health screening program located in Dunedin, Florida (USA). Our results show that contrary to the cross-sectional data, systolic and diastolic blood pressure levels tend to decrease with increasing age. Mean systolic blood pressure in women at the baseline visit (Visit 2) was 143 mmHg and three years later (Visit 5) it had dropped to 140 mmHg. This downward trend was consistent at all ages and for both men and women. Stratification by use of antihypertensive medication, weight change, and survivorship did not alter this association. Further follow-up of this cohort to Visit 7 revealed a U-shaped trend of blood pressure with aging. There was also clear evidence of a cohort effect, as the age-specific mean systolic blood pressure was consistently lower in each younger 5 yr birth cohort. Our results suggest that in a healthy elderly population, systolic and/or diastolic blood pressure levels do not increase with aging; this finding may have implications for the diagnosis and treatment of hypertension in the elderly.