Hypovitaminosis D: An underlying factor in influenza, ARDS mortality. What about COVID19?
There has been quite a bit of kerfuffle about the workhorse nutrient vitamin D. We are getting pinged daily on whether it should be used or avoided in the COVID19 pandemic. I believe this question was fueled by a recent write-up mentioning an in vitro study showing that D can up-regulate certain cytokines. Uniformly, my practitioner colleagues of all stripes—from famous thought leaders to those immersed in practice or research—vehemently disagree with the idea of stopping vitamin D given the years of solid, favorable clinical trials on it and, well, almost every condition we confront in medical practice.
Regarding acute respiratory distress syndrome (ARDS), in 2015, Dancer et al, discussed hypovitaminosis D as implicated in the pathogenesis of sepsis, ICU mortality and found it to be COMMON in people who develop ARDS:
“In ARDS cases, vitamin D deficiency was ubiquitous. Survivors of ARDS had significantly higher levels of vitamin D than non-survivors.”
Plasma 25(OH)D3 levels in acute respiratory distress syndrome (ARDS) versus at risk and normal controls. The horizontal bar represents the median, and the boxes represent IQRs. Vertical lines show minimum–maximum range. Fifty-two patients with ARDS, 57 at-risk patients undergoing esophagectomy, 18 healthy controls.
As I wrote about in 2018, a large metanalysis conducted in 2017 showed D supplementation prevented acute respiratory tract infections (most significantly in those correcting severe deficiency).
Not surprisingly—you know where I am going with this—it looks like severe hypovitaminosis D may underscore the high impact of COVID in Italy. From March 20th BMJ rapid response:
“Interestingly, epidemiological data report that Italy is one of the countries with the highest prevalence of hypovitaminosis D in Europe. A study from Isaia et al on 700 women aged 60-80 yrs in Italy found values of 25OH vitaminD lower than 5 ng/ml in 27% of the women and lower than 12 ng/ml in as many as 76%. (6) Moreover, the same group found a very high prevalence of hypovitaminosis D in elderly women with diabetes (7). Finally, another Italian study found a winter prevalence of hypovitaminosis D up to 32% of healthy postmenopausal women and to 82% in patients engaged in long-term rehabilitation programmes because of various neurological disorders.(8)”