Sex-specific associations of serum prolactin concentrations with cardiac remodeling: Longitudinal results from the Study of Health Pomerania (SHIP)

Background: Previous experimental and patient-based studies suggest that prolactin (PRL) and its 16 kDa fragment influence cardiovascular phenotypes by modulating angiogenesis. The association between serum PRL and cardiac remodeling in the general population is unknown. Methods: We evaluated 804 individuals (441 women) from the population-based Study of Health in Pomerania, aged >= 45 years, with available baseline serum PRL who underwent serial echocardiography at baseline and five-year follow-up. Left ventricular mass (LVM) was calculated and left ventricular hypertrophy (LVH) defined by sex-specific distributions of LVM. LV geometry was defined on the basis of relative wall thickness (RWT) and LVH. Sex-specific multivariable regression analyses were performed relating PRL (independent variable modelled as a continuous variable and as sex-specific quartiles) to change in LVM, RWT, and to incident LVH and abnormal geometry. Results: Baseline PRL concentrations were inversely associated with LVM change in men, but not in women (beta per 10% decrease in PRL: 0.37; 95% CI, 0.13-0.60 in men and -0.02; 95% CI, -0.21 to 0.17 in women, respectively). In men, baseline PRL concentrations were also inversely associated with incident LVH [first vs. fourth PRL quartile: relative risk (RR) 2.26 (95% CI, 1.20-4.24)] and altered LV geometry on follow-up [RR for incident concentric hypertrophy per 10% decrease in PRL: 1.20 (95% CI, 1.06-1.37)]. None of the longitudinal associations were observed in women. Conclusion: We observed inverse associations of PRL with LVM change, incident LVH, and altered LV geometry in men, but not in women. Additional studies are warranted to confirm our findings and to elucidate the mechanisms underlying these sex-specific associations. (C) 2012 Elsevier Ireland Ltd. All rights reserved.