The prevalence of multiple chronic conditions (MCCs) is continuously increasing among older adults in China, but few studies have explored complex pattern of MCCs from perspectives of patient demand and disease management.

This study aims to investigate the pattern distributions, correlates, and treatment burdens of MCCs.

Data were obtained from the 2018 and 2020 China Health and Retirement Longitudinal Study (CHARLS) waves, and the study sample included older adults aged≥60 years old (n=15 349). The generalized ordered logit model and the generalized linear model were used to examine correlates of MCCs complex pattern and its associations with outpatient/inpatient utilization and expenditure, respectively. All statistical analyses were weighted except for sample size.

Among the total sample of 15 349 older adults, there were 7 147 in 2018 and 8 202 in 2020; 2 054 participants[13.0%, defined as the relatively healthy group (RH group) ] had none of 12 chronic conditions defined in this study, 5 228 participants [33.7%, defined as the simple chronic illness group (SCI group) ] had 1-5 non-complex chronic conditions, 6 737 participants [44.7%, defined as the minor complex chronic illness group (MiCCI group) ] had 1-2 complex chronic conditions, and <6 non-complex chronic conditions, and 1 330 participants[8.6%, defined as the major complex chronic illness group (MaCCI group) ] had ≥3 complex chronic conditions or ≥6 non-complex chronic conditions. The proportion of MiCCI and MaCCI groups had an increase of 2.1% and 1.9% between 2018 and 2020, respectively. Among the SCI and MiCCI groups, the most prevalent chronic conditions were hypertension (49.2% and 56.1%) and arthritis/rheumatism (51.9% and 47.4%), respectively. Among MaCCI group, 82.0% had heart disease, and 67.9% had chronic lung diseases. There were statistically significant differences in the prevalence of chronic conditions among the three groups (P<0.05). Age, sex, education level, annual household expenditure per capita, medical insurance, depression status, and survey year were associated with being in SCI, MiCCI, and MaCCI groups (P<0.05) ; age, education level, urban-rural location, region, annual per capita household expenditure, and survey year were associated with being in MiCCI and MaCCI groups (P<0.05) ; age, region, annual per capita household expenditure, depression status, and survey year were associated with being in MaCCI group (P<0.05). In 2018, compared to the RH group, the MiCCI and MaCCI group had more outpatient numbers, and the SCI, MiCCI, and MaCCI groups had higher outpatient expenses, inpatient numbers and expenses (P<0.05). In 2020, compared to the RH group, the SCI, MiCCI, MaCCI groups utilized more outpatient and inpatient services (P<0.05) .

According to the most recent CHARLS data, over half of older adults in China suffers from complex chronic comorbidities, with 44.7% for the MiCCI group and 8.6% for MaCCI group. The heart disease and chronic lung disease was the most prevalent in the MaCCI group. Furthermore, as the complexity of multimorbidity increases, there is a noticeable increase in outpatient and inpatient utilization as well as medical expenditures. Therefore, it is recommended to explore effective MCC management models based on healthcare demands to improve health outcomes and reduce disease burdens.