Background: Laboratory and cross-sectional human studies suggest a potential role for prolactin in the pathogenesis of hypertension; however, the prospective association between prolactin and hypertension has not been previously reported.
Methods: We prospectively examined the association between daytime plasma prolactin levels and the risk of incident hypertension among 874 postmenopausal women who were participants of the Nurses' Health Study. Cox proportional hazards regression models were used to adjust for potential confounders.
Results: We identified 183 incident cases of hypertension during 8 years of follow-up. After adjusting for potential confounders, the relative risk of hypertension for a 1-standard deviation higher plasma prolactin was 1.31 (95% confidence interval 1.05-1.62). Compared with women with plasma prolactin levels of 8.0 ng/ml or below, the multivariable relative risk of incident hypertension for those with prolactin levels above 8.0 ng/ml was 1.34 (95% confidence interval 0.90-1.99).
Conclusion: A higher daytime plasma prolactin level is independently associated with an increased risk of incident hypertension among postmenopausal women.