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 ± 15.4 pmol/mL, P < 0.01) and hs-CRP (5.7 ± 6.9 vs. 1.9 ± 2.5 pg/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.