Abstract 16006: Prevalence and Incidence of Cardiovascular Risk Factors in Patients With Elevated Parathyroid Hormone Levels
Background: Vitamin D (Vit D) deficiency has been associated with cardiovascular (CV) risk, suggesting a role for bioregulators of bone and mineral metabolism in CV health. Vit D deficiency leads to secondary hyperparathyroidism, and both primary and secondary hyperparathyroidism are associated with CV pathology. Hence, interest recently has increased in a possible role for parathyroid hormone (PTH), an important regulator of calcium homeostasis. We tested whether elevated PTH is associated with CV risk factors and whether risk associations are dependent on or independent of Vit D status.
Methods: Subjects in the integrated Intermountain Healthcare system with measured PTH and Vit D levels, determined by the central laboratory, were studied (N = 9369, age = 63 ± 16 y, 36% male). Median time between PTH and Vit D levels was 0 days. PTH levels were defined as low (<15), normal (15–75), or elevated (>75 pg/mL). Prevalence and incidence of CV risk factors were determined by ICD-9 codes documented in electronic medical records at baseline and during an average of 2.0 ± 1.5 y (maximum, 7.5 y) follow-up.
Results: Baseline prevalence of CV risk factors by PTH level is shown in Table 1A, and incidence rates and their hazard ratios are given in Table 1B. Highly significant differential prevalence/incidence rates are noted across categories and specifically for PTH>75 pg/ml versus normal and low. PTH and Vit D correlated only weakly (r=0.15), and PTH-related associations persisted with only mild attenuation when adjusted for vitamin D status.
Conclusions: Elevated serum PTH is associated with a greater prevalence of baseline CV risk factors and predicts a greater likelihood of incident risk factor development during follow-up. PTH-associated risk persists when adjusted for Vit D status. These findings suggest that PTH represents an important new CV risk factor that adds independent predictive value to Vit D status.
- © 2010 by American Heart Association, Inc.