Blood pressure (BP) variability is recently identified as a risk factor for lifestyle-related diseases. Serum uric acid is a risk of incident hypertension, but little is known about the association between serum uric acid and BP variability.Design and Method:
This study included 5109 subjects (3685 women and 1424 men) of the Daiko Study, a part of the Japan Multi-Institutional Collaborative Cohort Study (J-MICC Study). BP was measured twice with an interval of two minutes resting. High, moderate, and low BP variability were defined as differences in the systolic BP measured twice; greater than or equal to 20 mmHg, 10–19 mmHg, and less than 10 mmHg, respectively. Second survey was conducted after five years from inclusion (2056 women and 730 men). Subjects taking antihyperuricemics (n = 39) were excluded.Results:
Serum uric acid was greater in subjects with high BP variability compared to those with low BP variability in women but not in men (4.60 vs. 4.28 mg/dl in women and 6.12 vs. 5.99 mg/dl in men for high vs. low BP variability). This difference was statistically significant after adjustment for age, mean systolic BP, and use of BP-lowering drugs in women (beta [95% CI] 0.15 [0.01–0.28] mg/dl for high vs. low BP variability).Results:
Serum uric acid remained greater after five years in subjects with high BP variability in baseline compared to those with low BP variability in both sexes (4.79 vs. 4.48 mg/dl in women and 6.30 vs. 5.92 mg/dl in men for high vs. low BP variability). This difference was statistically significant after adjustment for age, but not statistically significant after full adjustment in women.Conclusions:
Serum uric acid was associated with BP variability regardless of mean systolic BP in female general population. Our result may indicate that BP variability is associated with higher risk for lifestyle-related diseases, including hyperuricemia.