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.

中文翻译：

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德国弗兰肯地区癌症患者维生素 D 水平较低


背景 维生素 D 已被证明与降低 COVID-19 的风险和严重程度有关，并对癌症的所有特征发挥调节作用。本研究的目的是分析我们位于德国法兰克地区的诊所的一组癌症患者的维生素 D 状况。方法 25-羟基维生素 D 浓度可用于我们诊所前瞻性试验中纳入的 116 名患者。使用 Kendall τ 相关系数和线性回归研究维生素 D 与人体测量和血液参数的关联。结果 共有 57 名患者（49.1%）存在维生素 D 缺乏（<20 ng/mL），其中 92.2% 未达到推荐的维生素 D 水平 40 ng/mL。维生素 D 与白细胞计数 (τ = -0.173，p = 0.007) 和 C 反应蛋白浓度 (τ = -0.172，p = 0.007) 之间存在很强的负相关关系。在线性回归中，预测维生素 D 水平的最重要变量是（按照重要性递减的顺序）季节、脂肪质量指数、血小板和白细胞计数。结论 尽管 10 多年前就呼吁医学界解决德国普遍存在的维生素 D 缺乏问题，但我们的数据表明这些措施并未奏效。癌症患者的维生素 D 水平较低，应通过合理的阳光照射和补充剂来纠正。