The impact of mental and physical multimorbidity on healthcare utilization and health spending in China: A nationwide longitudinal population‐based study

In China, little evidence exists on the effect of mental and physical multimorbidity on individuals and the health system. This study aims to examine the prevalence of mental-physical multimorbidity and its impact on health service utilization and health expenditures.We conducted a panel study using two waves of data (in 2011 and 2015) from the China Health and Retirement Longitudinal Study, including 10,181 participants aged 45 years and older. Generalized linear regression models were used to assess the association of multimorbidity with total health expenditure and out-of-pocket expenditure (OOPE) on outpatient and inpatient care. Random-effects logistic regression models were used to examine the impact of multimorbidity on outpatient visits, admission to hospital and incidence of catastrophic health expenditure (CHE).Overall, 3210 participants (31.53% of 10,181) had mental-physical multimorbidity in 2015 in China. Compared to patients with a single physical disease, individuals with physical-mental multimorbidity had over 150% of the increase in the number of outpatient visits and days of hospitalization. The percentage change of OOPE for outpatient and inpatient care was 156.8% and 163.6%, respectively. Mental-physical multimorbidity was associated with an increased likelihood of experiencing CHE (OR = 2.205, 95% CI = 2.048, 2.051).Multimorbidity, particularly mental-physical multimorbidity, is associated with higher levels of health service use and a greater financial burden to individuals in China. Healthcare system needs to shift from single-disease models to new financing and service delivery models to more effectively manage mental-physical multimorbidity.