The problem of frailty caused by acute infection and future health management strategies to improve frailty

Background We aimed to analyze changes in frailty associated with long-COVID, while providing effective health management measures to improve frailty. Methods We conducted a 4-month follow-up cohort study involving 2,471 participants to analyze changes in body frailty after the prevalence of COVID-19 in China. We performed interrupted time series analysis to estimate the impact of acute infection on the changes in frailty. The time-dependent COX model was considered to assess the association between frailty status and infection, and sensitivity analysis was performed to verify the stability of the results. In addition, we established a traditional Cox model to analyze the relationship between healthy behaviors and infections, aiming to improve health management and reduce frailty. Results There were significantly elevated trend changes in the frailty index compared to the prepandemic period in the total population (+0.029[0.016, 0.041], p < 0.001), and the frailty index was found to be higher in female individuals and people aged over 65 years. Participants with moderate frailty (HR = 1.19, 95% CI: 1.04–1.35, p < 0.001) and severe frailty (HR = 1.34, 95%CI: 1.15–1.56, p < 0.001) had a significantly higher hazard of infection than those with mild frailty. Long-term health monitoring indicated that positive mood, appropriate physical activities, sufficient intake of grains and vegetables, and reduced intake of sugary drinks can improve frailty and ultimately reduce the risk of infection. Conclusion In this study, it was found that the population generally became more frail after the pandemic, and frailty increases the risk of acute reinfection. Therefore, it is necessary to carry out health management strategies to improve frailty.