Former smokers with COVID-19 face higher risk of death

In a cohort of veterans with COVID-19, former smokers are at higher risk of 30-day mortality compared with current smokers and nonsmokers, as reported in a study.

The analysis included a veteran population of 25,958 patients (median age 71 years, 95 percent men, 63 percent Caucasian) with COVID-19. Of these, 2,995 were current smokers, 12,169 were former smokers, and 8,392 had never smoked. The median length of hospital stay was 6 days (interquartile range [IQR], 3–12 days).

A total of 7,578 patients (29 percent) were admitted to the intensive care unit, and their median length of stay was 5 days (IQR, 2–10 days). There were 834 deaths documented within 7 days, 1,994 within 14 days, and 3,503 within 30 days.

The 30-day mortality was 13.5 percent among former smokers, 9.2 percent among current smokers, and 11.5 percent among nonsmokers. Multivariable logistic and Cox regression analyses confirmed that former smoking conferred a higher risk of 30-day mortality compared with nonsmoking (odds ratio, 1.15, 95 percent confidence interval [CI], 1.05–1.27; hazard ratio [HR], 1.13, 95 percent CI, 1.03–1.23) and with current smoking (HR, 1.16, 95 percent CI, 1.02–1.33).

Meanwhile, the risk did not differ between current smoking and nonsmoking.

Other risk factors for 30-day mortality included age, male sex, Hispanic or Latino ethnicity, and cirrhosis.