Frailty increases incidence risk of infection in the elderly: A population-based cohort study (Preprint)

BACKGROUND Background:Infectious diseases are among the leading causes of death and disability. As the population ages, it faces an enormous challenge with frailty.Nevertheless, there are only few prospective assessments on the association between frailty with infectious disease. Hence, research on frailty and infection is urgently needed. OBJECTIVE Objective: we aimed to examine the associations of frailty and infection disease. METHODS Methods: We conducted a prospective follow-up study of 11,930 elderly Chinese, dividing them into frail and healthy groups at baseline. Incidence data for infectious diseases were collected through the Chinese Disease Control and Prevention Information System – Infectious Disease Monitoring and Public Health Emergency Monitoring System. A questionnaire survey was used to assess frailty status. We compared the incidence rate ratio (IRR) of each disease stratified by age and sex. Cox proportional hazards regression was conducted to identify the effect of demographic factors and frailty on the risk of infectious diseases, with estimations of the hazard ratio (HR) and 95% confidence interval (CI). RESULTS Results: A total of 235 cases of 12 infectious diseases were reported during the study period, with an incidence of 906.21/100,000 person-years in the frailty group. In the same age group, the risk of infection was higher in men than women. Frail elderly had an HR for infectious diseases of 1.50 (95% CI: 1.14–1.97) compared with healthy elderly. We obtained the same result after sensitivity analyses. For respiratory tract transmitted diseases (IRR: 1.97, 95% CI: 1.44–2.71) and gastrointestinal tract transmitted diseases (IRR: 3.67, 95% CI: 1.39–10.74), frail elderly are at risk. Whereas no significant association was found for blood-borne, sexually transmitted and contact- transmitted diseases(IRR:o.76, 95%CI: 0.37-1.45). CONCLUSIONS Conclusion: our study provides additional evidence that frailty components are significantly associated with infection disease.Health care prfessional should pay more attention to frailty in infectious disease prevention and control.