Relationship between parathyroid hormone and subclinical myocardial dysfunction in patients with severe psoriasis

Background Psoriasis is associated with an increased risk of cardiovascular disease although the mechanism remains unclear. Recent studies have shown that such patients have a high prevalence of vitamin D (vit-D) deficiency and elevated parathyroid hormone (PTH) level. We hypothesized that vit-D deficiency and/or elevated PTH in psoriasis may contribute to left ventricular (LV) dysfunction. Methods Seventy-four patients with severe psoriasis with no known cardiovascular disease and 53 age- and gender-matched controls were recruited. All patients underwent detailed transthoracic echocardiography, including speckle tracking derived strains, and plasma levels of 25-hydoxyvitamin D (25-OHD), PTH and cardiac biomarkers including high sensitive C-reactive protein (hs-CRP), high sensitive troponin I (hs-TNI) and brain natriuretic peptide (BNP) were measured. Results Despite similar systolic and diastolic LV function, patients with severe psoriasis had impaired LV global longitudinal (-18.1 +/- 2.6 vs.-19.6 +/- 2.9%, P<0.01) and circumferential strain (-18.7 +/- 3.6 vs. -20.8 +/- 4.3%, P<0.01) compared with controls. Patients with severe psoriasis also had a significantly higher PTH (49.9 +/- 18.0 vs. 40.5 +/- 15.4pmol/mL, P<0.01) and hs-CRP (5.7 +/- 6.9 vs. 1.9 +/- 2.5pg/mL, P<0.01), but similar levels of 25-OHD, hs-TNI and BNP (all P>0.05) compared with controls. Importantly, PTH level was negatively correlated with LV global longitudinal strain (R=-0.30, P<0.01); and higher PTH level was independently associated with impaired global LV longitudinal strain (R=-0.33, P=0.04), independent of cardiovascular risk factors, vit-D status and serum biomarkers. Conclusions Severe psoriasis patients had an elevated PTH level and suffered from subclinical LV systolic dysfunction as detected by impaired global LV longitudinal strain. Importantly, a higher PTH level was independently associated with impaired global LV longitudinal strain.