COVID-19 has caused devastation globally mostly affecting countries in colder climates. Therefore, vitamin D is thought to be one of the contributing factors towards causation and severity. Many guidelines do not recommend vitamin D for treatment or prevention. Hence, we set out to do a global survey to understand the use and prescribing habits of vitamin D amongst clinicians. Methods: Online anonymous questionnaire was sent to clinicians enquiring in their prescribing habits of vitamin D and personal use of vitamin D. Results: 4,440 practicing clinicians were included in the analysis with majority of those that responded were from Asia followed by Europe. 82.9% prescribed vitamin D before COVID-19, more commonly amongst general practitioners (GPs) and Asian clinicians more likely to prescribe vitamin D (p<0.005). GPs were also more likely to prescribe vitamin D prophylactically to prevent COVID-19 (OR 1.47, p<0.005). Majority would also prescribe vitamin D to treat COVID-19 (72.5%; OR:1.81, p<0.005), as well as Asian clinicians (OR 4.57, p<0.005). 80.4% of respondents were taking vitamin D, more so in the 45-54 and 65-74 age groups (OR2.15 and 2.40, respectively), many of whom did so before COVID-19 (72.1%). Conclusion: Clinicians from different countries have acknowledged the role of vitamin D during the COVID-19 pandemic. This survey has shown that many clinicians would prescribe vitamin D for the prevention and treatment of COVID-19. Majority also would recommend measuring vitamin D levels but not so in patients with COVID-19.
