Seasonal pattern of vitamin D hydroxyl metabolite concentrations and their association with cardiac medications – An observational study

Abstract

ObjectivesThe sun is the primary source of vitamin D production, and seasonal changes can substantially influence vitamin D levels, which hardly any study has examined in cardiac patients. This research aims to measure 25(OH)D3 and 25(OH)D2 concentrations and assess their relation to the seasons and medications given to cardiac patients. MethodsWe collected 116 blood samples from 58 patients in autumn-winter and spring-summer seasons. Ultra-high-performance liquid chromatography-tandem mass spectrometry method was applied to determine 25(OH)D3 and 25(OH)D2 concentrations. The statistical assessment was performed using Statistica 13.3 with Plus Kit 3.0. ResultsOnly 9% of patients had 25(OH)D3 concentrations in the recommended range of 30–50 ng/mL. We found significantly higher 25(OH)D3 average levels in spring-summer period compared with autumn-winter period (P = 0.001). Older patients had a higher risk of vitamin D deficiency in autumn-winter (OR = 1.08; P = 0.011, OR = 0.32; P = 0.015, respectively). Average 25(OH)D2 concentrations between seasons were insignificant (Z = 1.04; P = 0.3). Vitamin D deficiency was significantly correlated with administration of angiotensin-II receptor blocker (OR = 7.49; P = 0.025), steroidal antiandrogen*age (OR = 1.039; P = 0.022). Other medications did not correlate with vitamin D deficiency, 9%NaCl (OR = 0.2; P = 0.04) and thiazide (0.076; P = 0.015). ConclusionThe prevalence of vitamin D deficiency and therapeutic drug monitoring are substantial in the observed group of cardiovascular patients, considering those with higher risk factors. Cardiac patients may benefit from vitamin D supplementation or dietary intervention to correct vitamin D levels. Further studies on more patients are required to confirm our results and identify other factors influencing 25(OH)D concentrations in cardiac patients.