Vitamin D levels in primary care patients: correlations with clinical, seasonal, and quality-of-life parameters

Fam Pract. 2022 Jul 19;39(4):678-684. doi: 10.1093/fampra/cmac012.

Abstract

Background: The prevalence of vitamin D deficiency varies across countries and few data exist in the adult population in Greece.

Objectives: To assess vitamin D levels in unselected patients from primary care and to investigate possible correlations with clinical, seasonal, and quality-of-life parameters.

Methods: In this cross-sectional study, 389 consecutive patients were included. They were grouped according to vitamin D status as vitamin D deficient (<20 ng/mL) and vitamin D sufficient groups (≥20 ng/mL). Demographic, Epworth Sleepiness Scale (ESS), Athens Insomnia Scale (AIS), Beck Depression Inventory (BDI), and Fatigue Severity Scale (FSS) scores were measured and compared between groups.

Results: Vitamin D deficiency (<20 ng/mL) was observed in 50.4% of the cohort. Female gender (76% vs 66%, P = 0.026), obesity (42% vs 26%, P = 0.005), and hypertension (55% vs 43%, P = 0.023) were higher in the vitamin D deficiency group compared with the group without deficiency. After multiparametric adjustments (for age, gender, obesity, comorbidities, and seasonality), hypertension (odds ratio [OR] = 2.338, 95% confidence interval [CI] = 1.257-4.349, P = 0.007), excessive daytime sleepiness (ESS >10; OR = 3.345, 95% CI = 1.124-9.948, P = 0.029), depressive symptoms (BDI >10; OR = 3.769, 95% CI = 0.984-14.443, P = 0.04), and fatigue (FSS >36; OR = 7.157, 95% CI = 0.855-59.877, P = 0.04) showed significant independent associations with vitamin D deficiency in specific subgroups of patients.

Conclusion: A large proportion of patients in primary care had vitamin D deficiency, independently associated with hypertension, sleepiness, depressive symptoms, and fatigue. Further research is needed in order to determine the role of vitamin D in these patients.

Keywords: comorbidities; depressive symptoms; fatigue; primary care; sleepiness; vitamin D deficiency.

Plain language summary

Vitamin D, also known as the “sunshine vitamin,” is an essential nutrient long known for its role in bone health. It is also thought to increase the risk of medical conditions such as cancer and cardiovascular disease. Over recent years, we are witnessing a high percentage of the population with vitamin D deficiency in most European countries; however, few data exist in the adult population in Greece. Based on these findings, we assessed vitamin D levels in patients from primary care and investigated possible correlations with clinical, seasonal, and quality-of-life parameters, including sleepiness, insomnia, and depressive symptoms and fatigue. We found a large proportion of patients in primary care to have vitamin D deficiency, which was associated with hypertension, sleepiness, depressive symptoms, and fatigue based on gender, age, and obesity status of patients. Therefore, vitamin D deficiency should be suspected in specific subgroup of patients. Nevertheless, further research is also needed in order to assess if vitamin D supplementation is likely to have a clinically relevant influence on hypertension and quality-of-life parameters.

MeSH terms

  • Adult
  • Cross-Sectional Studies
  • Depression / diagnosis
  • Fatigue / epidemiology
  • Female
  • Humans
  • Hypertension*
  • Obesity
  • Primary Health Care
  • Quality of Life
  • Seasons
  • Sleepiness
  • Vitamin D
  • Vitamin D Deficiency* / epidemiology

Substances

  • Vitamin D