Mendelian randomization analyses show that higher acetyl-carnitine and carnitine levels in blood protect against severe Covid19 (preprint)

Background: Severe Covid19 is characterised by a hyperactive immune response. Carnitine, an essential nutrient, and its derivative acetyl-carnitine can downregulate proinflammatory cytokines and has been suggested as a potential treatment for the disease. Methods: We carried out Mendelian randomization analyses using publicly available data from a large genome wide association study (GWAS) of metabolites and a collaborative genome wide study of Covid19 to investigate the nature of the relationship between carnitine and acetyl-carnitine and Covid19 infection, hospitalisation with Covid19 and very severe Covid19. We used the same methodology to determine whether carnitine was associated with co-morbidities commonly found among those with severe Covid19. Results: We found evidence of a protective effect against very severe Covid19 for both carnitine and acetyl-carnitine, with around a 40% reduction in risk associated with a doubling of carnitine or acetyl-carnitine (carnitine odds ratio (OR) = 0.56, 95% confidence intervals (CI) 0.33 to 0.95, p=0.03 and acetyl-carnitine OR=0.60, 95% CI 0.35 to 1.02, p=0.06), and evidence of protective effects on hopitalisation with Covid19. For acetyl-carnitine the largest protective effect was seen in the comparison between those hospitalised with Covid19 and those infected but not hospitalised (OR=0.34, 95%CI 0.18 to 0.62, p=0.0005). Conclusion: Carnitine and acetyl-carnitine merit further investigation in respect to the prevention of severe Covid19.

Risk of death among teachers in England and Wales during the Covid19 pandemic (preprint)

ObjectivesTo use publicly available data on mortality in England and Wales to estimate the extent of occupation risk from Covid19 among teachers and others working in schools. DesignAnalysis of national death registration data from the Office for National Statistics. SettingEngland and Wales from March 20th - 28th December 2020, during the Covid-19 pandemic. ParticipantsWe compared mortality rates among teachers and other school workers to all working aged people and all professional occupations. Primary and Secondary outcomesDeaths with Covid19 was our primary outcome and death from all causes was our secondary outcome. ResultsWe found that the absolute mortality rates for deaths with Covid19 were generally low amongst teachers ([≤]39 per 100,000); they were also low relative to many other occupations. However, both male and female secondary school teachers had slightly higher risks of dying with Covid19 relative to all working aged people and greater risk compared to all professionals, primary school teachers did not have an elevated risk. The mortality risk for all causes was also higher in teachers compared to the working aged population. Excess deaths from all causes were higher among those aged over 65 who were working in schools compared to all over 65s who were currently working and compared to all professionals in this age group. ConclusionThere is weak evidence that secondary school teachers (in particular females) may have a slightly higher risk of Covid19 mortality, but compared to many other occupations their risk is low. Further research is needed to determine why there is a high proportion of excess of deaths which were apparently not due to Covid19 among over 65 year-olds working in schools.