Determinants of post discharge mortality among hospitalized COVID-19 patients

Abstract

Background & objectives: The post-acute effects of COVID-19 are continually being updated. This investigation was conducted to evaluate the determinants of post discharge mortality in hospitalized COVID-19 patients, especially 18-45 yr of age.

Methods: A series of three nested case-control analyses was conducted on follow up data collected in the National Clinical Registry for COVID-19 between September 2020 and February 2023 from 31 hospitals. Matching (1:4) was done by the date of hospital admission ±14 days for the following comparisons: (i) case-patients reported as dead vs. controls alive at any contact within one year follow up; (ii) the same in the 18-45 yr age group and (iii) case-patients reported as dead between the first and one year of follow up vs. controls alive at one year post discharge.

Results: The one year post discharge mortality was 6.5 per cent (n=942). Age [≤18 yr: adjusted odds ratio (aOR) (95% confidence interval [CI]): 1.7 (1.04, 2.9); 40-59 yr: aOR (95% CI): 2.6 (1.9, 3.6); ≥60 yr: aOR (95% CI): 4.2 (3.1, 5.7)], male gender [aOR (95% CI): 1.3 (1.1, 1.5)], moderate-to-severe COVID-19 [aOR (95% CI): 1.4 (1.2, 1.8)] and comorbidities [aOR (95%CI): 1.8 (1.4, 2.2)] were associated with higher odds of post-discharge one-year mortality, whereas 60 per cent protection was conferred by vaccination before the COVID-19 infection. The history of moderate-to-severe COVID-19 disease [aOR (95% CI): 2.3 (1.4, 3.8)] and any comorbidities [aOR (95% CI): 3 (1.9, 4.8)] were associated with post-discharge mortality in the 18-45-yr age bracket as well. Post COVID condition (PCC) was reported in 17.1 per cent of the participants. Death beyond the first follow up was associated with comorbidities [aOR (95%CI): 9.4 (3.4, 26.1)] and reported PCC [aOR (95% CI): 2.7 (1.2, 6)].

Interpretation & conclusions: Prior vaccination protects against post discharge mortality till one year in hospitalized COVID-19 patients. PCC may have long term deleterious effects, including mortality, for which further research is warranted.

Keywords: India; observational study; one-year mortality; persistent symptoms; post-acute COVID symptoms.

Fig. 1

Participant selection for nested case-control analyses to determine the risk factors of post discharge death within one year of follow up, at all ages and the 18-45 yr age group (matched by the date of hospital admission±14 days, 1:4).

Fig. 2

Participant selection for nested case-control analysis to determine the risk factors of late post discharge death, (beyond the first follow up till one year), in the participants for whom status is known both at the first follow up and one year (matched by the date of hospital admission±14 days, 1:4).