Abstract P021: Parathyroid Hormone and the Risk of Incident Hypertension: The Atherosclerosis Risk in Communities Study (ARIC)
Background: Recent evidence suggests that parathyroid hormone (PTH) has effects on vascular smooth muscle cells, the renin-angiotensin system and kidney function. Thus, PTH levels may alter blood pressure. The distribution of serum PTH also varies by race. We examined the relation between PTH and incident hypertension, and explored race-specific associations.
Methods: A total of 7,504 ARIC study participants (1,264 Black, 6,240 White, median age 56) without hypertension at baseline in 1990-1992 were followed through 1996-1998. Incident hypertension was defined during the follow-up exams by elevated measured blood pressure (DBP≥ 90 mm Hg, or SBP≥140 mm Hg, based on the average of 2 measurements) and/or use of hypertension medications. Complementary log-log regression was used to evaluate the independent association of baseline serum PTH with incident hypertension.
Results: The median level of PTH was 38.2 pg/mL overall, 37.4 pg/mL in whites, and 42.7 pg/mL in blacks. During a median follow-up of 6 years, 1,487 White and 509 Black participants developed hypertension. In the full sample, PTH was positively associated with incident hypertension after adjustment for demographics, though the association was quite modest after accounting for behavioral risk factors (Table). Although there was no significant interaction by race (p for interaction = 0.60), there was some evidence that the association differed by race. Among Blacks, PTH was positively associated with incident hypertension, independent of demographics and behavioral risk factors (P for linear trend 0.003). Among whites, PTH was not significantly associated with hypertension risk. Results were similar when a clinical cut-point for elevated PTH was employed [HR, 95% CI for ≥ 65 vs. < 65 pg/mL: blacks = 1.24 (1.02-1.54); whites = 0.95 (0.78, 1.16)]
Conclusions: In this large, population-based cohort, PTH levels were not associated with the risk of hypertension. However, a potential association between PTH and hypertension in blacks may merit further study.
Author Disclosures: L. Yao: None. A. Folsom: None. W. Tang: None. E. Michos: None. J. Pankow: None. E. Selvin: None. A. Alonso: None. P. Lutsey: None.
- © 2015 by American Heart Association, Inc.