Serum 25-hydroxyvitamin D concentrations, well being, and presenteeism among hospital porters: a single-center cross-sectional study in Greece

Abstract

Vitamin D deficiency is common among healthcare workers owing to indoor work, shift patterns, and limited sunlight, even in Mediterranean countries, yet evidence for hospital porters is scarce. This single-center, cross-sectional study assessed serum 25-hydroxyvitamin D [25(OH)D] concentrations and their unadjusted associations with psychological well being and presenteeism among hospital porters in a Greek tertiary university hospital in Alexandroupolis, Northern Greece, between March and June 2026. Of 46 eligible porters, 42 participated (91.3%). Serum 25(OH)D was measured by electrochemiluminescence immunoassay (ECLIA). Participants completed validated Greek versions of the WHO-5 Well Being Index and the Stanford Presenteeism Scale (SPS-6). Demographic, occupational, lifestyle, and clinical data, including BMI, were obtained from occupational-health records. The median 25(OH)D was 18.7 ng/mL (IQR 14.3–26.0), with 59.5% classified as deficient; mean BMI was 26.7 ± 3.7 kg/m2. In unadjusted analyses, 25(OH)D correlated positively with WHO-5 (rho = 0.371, p = 0.015) but not SPS-6, and inversely with BMI (rho = −0.465, p = 0.002). Surgical porters had lower 25(OH)D (p = 0.025) but higher BMI (p = 0.029) than general ward porters. Because no multivariable adjustment was possible and residual confounding cannot be excluded, these associations are exploratory and hypothesis-generating. These findings highlight the need for longitudinal research in this understudied workforce.