Faculty of Economics and Business, Goethe University Frankfurt, Theodor-W.-Adorno-Platz 4, 60629, Frankfurt, Germany.
Sci Rep. 2020 Oct 19;10(1):17705. doi: 10.1038/s41598-020-74825-z.
Prior studies indicate the protective role of Ultraviolet-B (UVB) radiation in human health, mediated by vitamin D synthesis. In this observational study, we empirically outline a negative association of UVB radiation as measured by ultraviolet index (UVI) with the number of COVID-19 deaths. We apply a fixed-effect log-linear regression model to a panel dataset of 152 countries over 108 days (n = 6524). We use the cumulative number of COVID-19 deaths and case-fatality rate (CFR) as the main dependent variables and isolate the UVI effect from potential confounding factors. After controlling for time-constant and time-varying factors, we find that a permanent unit increase in UVI is associated with a 1.2 percentage points decline in daily growth rates of cumulative COVID-19 deaths [p < 0.01] and a 1.0 percentage points decline in the CFR daily growth rate [p < 0.05]. These results represent a significant percentage reduction in terms of daily growth rates of cumulative COVID-19 deaths (- 12%) and CFR (- 38%). We find a significant negative association between UVI and COVID-19 deaths, indicating evidence of the protective role of UVB in mitigating COVID-19 deaths. If confirmed via clinical studies, then the possibility of mitigating COVID-19 deaths via sensible sunlight exposure or vitamin D intervention would be very attractive.
先前的研究表明，紫外线-B（UVB）辐射通过维生素 D 合成对人体健康具有保护作用。在这项观察性研究中，我们根据紫外线指数（UVI）经验性地概述了 UVB 辐射与 COVID-19 死亡人数之间的负相关关系。我们将一个包含 152 个国家 108 天数据的面板数据集（n=6524）应用于固定效应对数线性回归模型。我们将 COVID-19 死亡人数和病死率（CFR）的累计数作为主要因变量，并将 UVI 效应与潜在的混杂因素隔离开来。在控制了时不变和时变因素后，我们发现 UVI 每增加一个单位，COVID-19 死亡人数的日增长率就会下降 1.2 个百分点[P<0.01]，CFR 的日增长率就会下降 1.0 个百分点[P<0.05]。这些结果代表 COVID-19 死亡人数的日增长率（-12%）和 CFR（-38%）有显著的百分比降低。我们发现 UVI 与 COVID-19 死亡之间存在显著的负相关关系，这表明 UVB 在减轻 COVID-19 死亡方面具有保护作用。如果通过临床研究得到证实，那么通过合理的阳光照射或维生素 D 干预来减轻 COVID-19 死亡的可能性将非常有吸引力。
