Low Vitamin D Status in a Cancer Patient Population from Franconia, Germany

Klement, Rainer Johannes; Koebrunner, Petra S.; Krage, Kelley; Sweeney, Reinhart A.

BACKGROUND: Vitamin D has been shown to be associated with reduced risk and severity of COVID-19 and exerts regulating effects on all hallmarks of cancer. The goal of this study was to analyze the vitamin D status of a cancer patient cohort from our clinic in the Franconian region, Germany. METHODS: 25-hydroxyvitamin D concentrations were available for 116 patients included in prospective trials in our clinic. Associations of vitamin D with anthropometric and blood parameters were investigated using Kendall's τ correlation coefficients and linear regression. RESULTS: A total of 57 patients (49.1%) were vitamin D deficient (<20 ng/mL), and 92.2% did not meet the recommended vitamin D level of 40 ng/mL. There was a strong negative association between vitamin D and leukocyte count (τ = −0.173, p = 0.007) and C-reactive protein concentration (τ = −0.172, p = 0.007). In linear regression, the most important variables for predicting vitamin D levels were (in order of decreasing importance) season, fat mass index, platelet, and leukocyte count. CONCLUSIONS: Despite appeals towards medical societies to target widespread vitamin D deficiency in Germany more than 10 years ago, our data indicate that these have been without avail. Low vitamin D levels in cancer patients should be corrected using reasonable sun exposure and supplements.