Serum Parathyroid Hormone in Relation to All-Cause and Cardiovascular Mortality: The Hoorn Study

Context: Higher PTH concentrations have been associated with fatal cardiovascular diseases (CVDs), but data in the general population are scarce. Objective: We investigated whether higher PTH concentrations are prospectively associated with all-cause and CVD mortality. Design, Setting, Participants: This study used data from the Hoorn Study, a prospective population-based cohort with baseline measurements between 2000 and 2001. We included 633 participants, mean age 70.1 +/- 6.6 years, 51% female. Serum intact PTH was measured using a 2-site immunoassay. Main Outcome Measures: Outcomes were all-cause and CVD mortality based on clinical files and coded according to the International Classification of Diseases, ninth revision. We used Kaplan-Meier plots to estimate survival curves and Cox regression to estimate hazard ratios (HRs) using season-specific PTH quartiles. Results: During a median follow-up of 7.8 years, 112 participants died, of which 26 deaths (23%) were cardiovascular. Survival curves by PTH quartiles differed for all-cause mortality (log-rank P = .054) and CVD mortality (log-rank P = .022). In a multivariate model, the highest PTH quartile was associated with all-cause mortality; HR = 1.98 (1.08, 3.64). Kidney function slightly attenuated the PTH risk association, but risk persisted; HR = 1.93 (1.04, 3.58). The results for CVD mortality showed a similar pattern, although the association was significant only in a threshold model (quartile 4 vs quartile 1-3); HR = 2.56 (1.11, 5.94). Conclusions: Among a general older population, higher PTH concentrations were associated with higher all-cause mortality risk, mostly explained by fatal CVD events. We suggest to evaluate whether individuals with high PTH concentrations benefit from therapeutic approaches targeted to decrease PTH concentrations. (J Clin Endocrinol Metab 98: E638-E645, 2013)