Quantifying the Adverse Effects of Long COVID on Individuals' Health After Infection: A Propensity Score Matching Design Study.

OBJECTIVE

To evaluate the prevalence and influencing factors of long COVID, and measure the difference in health status between long COVID and non-long COVID cases.

METHODS

A cross-sectional survey was conducted from February 1 to 8, 2023, using a stratified random sampling method in four regions (eastern [Changzhou], central [Zhengzhou], western [Xining] and northeastern [Mudanjiang]) of China. The survey collected COVID-19 patients' socio-demographic characteristics and lifestyles information. The scores of lifestyles and health status range from 5 to 21 and 0 to 100 points, respectively. The criteria of "persistent health problems after 4 weeks of COVID-19 infection" issued by the US Centers for Disease Control and Prevention was used to assess long COVID. Multiple linear regression was used to analyze the influencing factors of the health. The bootstrap method was used to analyze the lifestyles' mediating effect. Propensity score matching (PSM) was used to evaluate the net difference in health scores between long COVID and non-long COVID cases.

RESULTS

The study included 3165 COVID-19 patients, with 308 (9.73%) long COVID cases. The health score of the long COVID cases (74.79) was lower than that of the non-long COVID cases (81.06). After adjusting for potential confounding variables, we found that never focused on mental decompression was a common risk factor for the health of both groups. Lifestyles was the mediating factor on individuals' health. After PSM, the non-long COVID cases' health scores remained higher than that of long COVID cases.

CONCLUSION

The proportion of long COVID cases was low, but they were worse off in health. Given the positive moderating effect of healthy lifestyles on improving the health of long COVID cases, healthy lifestyles including mental decompression should be considered as the core strategy of primary prevention when the epidemic of COVID-19 is still at a low level.