https://www.medrxiv.org/content/10.1101/2021.09.22.21263977v1(note, not peer reviewed yet)
quote:
Results: One population study and seven clinical studies were identified, which reported D3 blood levels pre-infection or on the day of hospital admission. They independently showed a negative Pearson correlation of D3 levels and mortality risk (r(17)=-.4154, p=.0770/r(13)=-.4886, p=.0646). For the combined data, median (IQR) D3 levels were 23.2 ng/ml (17.4 – 26.8), and a significant Pearson correlation was observed (r(32)=-.3989, p=.0194). Regression suggested a theoretical point of zero mortality at approximately 50 ng/ml D3.
Conclusions: The two datasets provide strong evidence that low D3 is a predictor rather than a side effect of the infection. Despite ongoing vaccinations, we recommend raising serum 25(OH)D levels to above 50 ng/ml to prevent or mitigate new outbreaks due to escape mutations or decreasing antibody activity.
I'm still staggered no one is bothering to pay for proper vitamin D studies, especially for the already active forms of Vit d like Calcitriol. Eg
https://pubmed.ncbi.nlm.nih.gov/34508882/quote: There were 3 deaths and 4 readmissions in the control group and 0 deaths and 2 readmissions in the calcitriol group.
Far too small numbers in itself, but there is enough info to warrant proper testing.