Health Influence and Association Analysis of Inpatient Service Under‐Utilization in Older Adults With Multimorbidities: A National Study in China

Background: In the Chinese aging population characterized by rising chronic comorbidities, this study investigated under-utilization of inpatient services (hospitalization) among elderly individuals with multimorbidities, aiming to elucidate its health impacts and contributing factors so as to inform policy. Methods: A national household investigation was conducted using cross-sectional and prospective methods. The study included 3636 adults aged ≥ 60 with multimorbidities from the China Health and Retirement Longitudinal Study (CHARLS 2015), with follow-up health assessments in 2018. Cox regression was employed to analyze the health consequences of non-hospitalization; logistic regression analysis identified contributing factors. Results: Overall, 8.7% of elderly adults with multimorbidities declined hospitalization despite medical necessity. After adjusting for demographics and lifestyle factors, we found that this refusal was significantly linked to a deterioration in self-rated health (hazard ratio [HR]: 1.273; 95% confidence interval [CI]: 1.091-1.484) and inability to work normally (HR: 1.244; 95% CI: 1.060-1.459) and inability to perform normal household tasks (HR: 1.579; 95% CI: 1.250-1.996) after 3 years. In the fully adjusted model, non-hospitalization despite medical necessity remained a statistically significant risk factor for a decreased ability to perform normal household chores (HR: 1.403; 95% CI: 1.064-1.851), particularly affecting families with poor economic status (HR: 1.529; 95% CI: 1.003-2.332). Key independent factors for non-hospitalization despite medical needs included physical dysfunctions (odds ratio [OR]: 2.646; 95% CI: 1.644-4.260), inadequacy of long-term care (OR: 1.341; 95% CI: 1.006-1.787), being very dissatisfied with marriage (OR: 2.629; 95% CI: 1.137-6.079), and increased number of chronic multimorbidities (OR: 1.292; 95% CI: 1.190-1.402). Conclusions: Inadequate inpatient service utilization among multimorbid elderly individuals exacerbates health risks, particularly for those with physical limitations, marital distress, care deficits, and high chronic disease burdens. Therefore, targeted interventions are urgently required.