TOPLINE:

Analysis of routinely collected laboratory data from nearly 300,000 patients in Germany revealed significant decreases in vitamin D levels during the COVID pandemic. Older women showed the largest decrease in mean vitamin D levels and the largest increase in vitamin D deficiency rates compared with other age and sex subgroups.

METHODOLOGY:

• Although vitamin D is vital for bone integrity and immune responses, the COVID pandemic — with stay-at-home mandates, curtailed outdoor time, and altered diets — sparked worries that reduced exposure to sunlight and nutritional shifts would diminish vitamin D status.
• Researchers analyzed routinely collected laboratory data from 292,187 patients in Bavaria, Germany, comparing vitamin D levels before (March 2018-February 2020) and during (March 2020-February 2022) the pandemic.
• Participants were required to be aged 18 years or older, residing in Bavaria, and have at least one valid vitamin D measurement, with serum 25-hydroxy vitamin D levels measured using immunoassays.
• Changes in vitamin D levels were assessed across age groups (18-39, 40-59, and 60+ years), both sexes, and all four seasons.

TAKEAWAY:

• Mean vitamin D levels decreased significantly from 26.7 μg/L pre-pandemic to 26.0 μg/L during the pandemic (P < .001), with vitamin D deficiency rates increasing from 31.2% to 35.2% during the same period (P < .001).
• Compared with other age groups, young adults aged 18-39 years exhibited a smaller decline of vitamin D levels but a greater increase in vitamin D deficiency rates (from 34.6% to 37.8%).
• When grouped by sex, overall, women saw a larger decrease in vitamin D levels than men; the decline in mean vitamin D levels and increase in vitamin D deficiency rates were particularly pronounced among older women compared with other age and sex subgroups.
• An analysis of seasonal variations revealed that the largest decline in mean vitamin D levels occurred in spring (from 26.2 μg/L to 23.9 μg/L; P < .001), followed by winter (from 24.5 μg/L to 23.8 μg/L; P < .001).

IN PRACTICE:

“These findings underscore the need to prioritize addressing vitamin D deficiency in public health strategies and suggest that other nutritional deficiencies may also require attention during health crises,” the authors wrote.

SOURCE:

This study was led by Lea Skapetze, Institute for Medical Information Processing, Biometry, and Epidemiology, Faculty of Medicine, LMU Munich, Munich, Germany. It was published online on in Nature Communications.

LIMITATIONS:

The study’s observational nature limited the ability to establish direct causality between the pandemic and vitamin D deficiencies. While data came from a standardized laboratory provider, potential data quality concerns may have existed. The findings, specific to Bavaria, may not be generalizable to regions with different healthcare systems, climates, or population structures.

DISCLOSURES:

Two authors declared being employed by Health Data Technologies GmbH (Honic).

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.