Longitudinal change in blood pressure and risk of end-stage renal disease in a community-based cohort in Okinawa.

Background: The appropriate blood pressure target to prevent end-stage renal disease (ESRD) is controversial.

Methods: We examined the association between systolic blood pressure (SBP) changes and ESRD incidence in 69,575 participants from the Okinawa general population aged ≥ 20 years who underwent health check-ups in 1993 and more than once in 1994-1996. ESRD incidence was identified using dialysis registry until 2011. Cox proportional hazards model was used to estimate hazard ratio (95% confidence interval) with confounding factor adjustment.

Results: At baseline, 29.9%, 22.1%, 20.6%, and 27.5% of subjects had SBP < 120, 120-129, 130-139, and ≥ 140 mmHg, respectively. Only 405 subjects developed ESRD. After 1 year, SBP was lowered, unchanged, and elevated in 20.8%, 54.3%, and 24.9% of subjects, respectively. Compared to the subjects with SBP < 120 mmHg both at baseline and the second measurement, there was no significant risk of ESRD in those who had SBP < 130 mmHg both at baseline and 1-3 years and or those with baseline SBP 130-139 mmHg and 1- to 3-year SBP < 140 mmHg. Subjects with baseline SBP 120-129 mmHg and 1- and 2-year SBP ≥ 130 mmHg were not significant (1.51 [0.86-2.66] and 1.73 [0.95-3.15], respectively) but 3-year SBP ≥ 130 mmHg had a significant ESRD risk (2.37 [1.23-4.56]). Subjects with baseline SBP ≥ 130 mmHg and 1- to 3-year SBP ≥ 140 mmHg had significant ESRD risk.

Conclusion: Subjects with SBP < 130 mmHg at baseline and 1-3 years showed no significant risk of developing ESRD, in the general population.