Non-communicable disease and the risk of infection death: a UK Biobank prospective cohort study

Drozd, M.; Lillie, P.; Pujades-Rodriguez, M.; Straw, S.; Morgan, A. W.; Kearney, M. T.; Witte, K. K.; Cubbon, R. M.

Objectives: Non-communicable diseases (NCDs) have recently been highlighted as important risk factors for COVID-19 fatality. We set out to investigate the association between NCDs and the risk of death from any infection in the pre-COVID-19 era. Design: Prospective population-based study Setting: UK Biobank Participants: 493,295 participants Main outcome measures: Infection death prior to December 31st 2019. Results: During 5,277,344 participant-years of follow-up, 1,385 infection deaths occurred, accounting for 5% of all deaths. Competing risks regression revealed that advancing age, male sex, smoking, socio-economic deprivation and all studied NCDs were independently associated with both the risk of infection death and non-infection death; ethnicity was associated with neither. Only smoking, socio-economic deprivation, hypertension, respiratory disease, chronic kidney disease, psychiatric disease and rheumatological disease were associated with greater hazard ratios for infection than non-infection death. Accrual of multimorbidity was also associated with a greater increases in the risk of infection death (HR 9.03 [95% confidence interval 6.61 to 12.34] for 5+ comorbidities versus none; p<0.001), than non-infection death (HR 5.68 [95% confidence interval 5.22 to 6.17] for 5+ comorbidities versus none; p<0.001). Conclusions: Diverse NCDs are associated with increased risk of infection death, suggesting that recently reported associations with COVID-19 death may be non-specific. Moreover, only a subset of NCDs, together with the accrual of multimorbidity, smoking and socio-economic deprivation, are associated with greater relative risks of infection death than other causes of death. Further research is needed to define why these risk factors are biased toward infection death so that more effective preventative strategies can be targeted to high-risk groups.