Male sex, old age, smoking contribute to COVID-19 progression

The coronavirus disease 2019 (COVID-19) is more likely to progress to a critical illness or lead to death in men, elderly adults and smokers, according to a new meta-analysis.

“This study analysed the risk factors for progression to critical illness or death in COVID-19 patients to help assess patient status and identify critical patients early,” researchers said. “Pay close attention to these risk factors, and when relevant laboratory risk value appears, timely and personalized treatment regimens are needed to enhance the efficacy and reduce the risk of death.”

Thirteen studies were retrieved from the databases of Pubmed, Embase, Web of Science and CNKI, yielding a total of 3,027 patients. There were significantly more males in the subgroup of patients who died or who had critical illness (odds ratio [OR], 1.77, 95 percent confidence interval [CI], 1.43–2.19; p<0.00001). [J Infect 2020;10.1016/j.jinf.2020.04.021]

Moreover, those who had critical disease or died were generally older than counterparts who had milder COVID-19. Pooled analysis also showed that the proportion of patients >65 years of age was significantly larger in the critical disease/death subgroup (OR, 6.01, 95 percent CI, 3.95–9.16; p<0.00001).

Similarly, current smokers were more likely to develop critical COVID-19 or to die from the disease (OR, 2.04, 95 percent CI, 1.32–3.15; p=0.006). Heterogeneity for the sex, age and smoking analyses were nonsignificant.

Comorbidities also contributed to worsening COVID-19. The proportion of diabetes (OR, 3.68, 95 percent CI, 2.68–5.03; p<0.00001), cardiovascular diseases (OR, 5.19, 95 percent CI, 3.25–8.29; p<0.00001) and respiratory diseases (OR, 5.15, 95 percent CI, 2.51–10.57; p<0.00001) were all significantly higher in patients who died or who had critical disease.

In terms of clinical symptoms, shortness of breath or dyspnoea was significantly more common among those with worse COVID-19 (OR, 4.16, 95 percent CI, 3.13–5.53; p<0.00001).

Laboratory parameters also correlated with disease progression and fatality. These included high levels of aspartate aminotransferase, creatinine, hypertensive cardiac troponin I, procalcitonin, lactate dehydrogenase and D-dimer. On the other hand, a low white blood cell count was significantly protective.

“The quality of the literature included in this study is high, the analysis is rigorous, and the conclusions drawn by the study are highly credible,” the researchers said, adding that some limitations need consideration.

Most of the studies included, for example, were cross-sectional in design, and majority of the patients included were Chinese. These may limit the generalizability of the results. In addition, other detailed patient information was unavailable at the time of analysis.

“The conclusions of this meta-analysis still need to be verified by more relevant studies with more careful design, more rigorous execution and larger sample size,” they added.