Association between multimorbidity and intrinsic capacity among older Chinese adults: evidence from the CHARLS 2011-2015.

PURPOSE: To investigate the relationships between multimorbidity, patterns, and intrinsic capacity (IC) transitions in older Chinese adults.

METHODS

The data were obtained from the China Health and Retirement Longitudinal Study (CHARLS) from 2011 to 2015. IC evaluations were conducted in 2011 and 2015, encompassing cognition capacity, locomotion capacity, vitality capacity, psychological capacity, and sensory capacity. Based on the IC status in 2011 and 2015, four distinct IC transitions were defined. Multimorbidity patterns were determined at baseline through latent class analysis involving 14 chronic conditions. The associations between multimorbidity patterns and IC transitions were examined using multinomial logistic regression.

RESULTS

Among 3569 participants aged 60 and above, 53.0% were male, with a median age of 65 years. Regarding their condition counts, 10.9% had no disease, 24.3% had only one disease, and 64.8% had multimorbidity. Within the group with multimorbidity, 58.0% experienced sustained impairment in IC, a notably higher percentage compared to those with no disease (45.6%) and those with only one disease (50.6%). Compared to those with no disease, multimorbidity was significantly associated with IC sustained impairment after adjusting for all covariates (OR = 1.64; 95%CI = 1.20-2.23). Among the 2314 participants with multimorbidity, three multimorbidity patterns were identified: metabolic pattern (27.1%), arthritis-stomach pattern (64.5%), and respiratory pattern (8.4%). Compared to the metabolic pattern, the arthritis-stomach and respiratory patterns exhibited a higher risk of sustained impairment in IC; however, there was no significant difference observed between the latter two multimorbidity patterns.

CONCLUSIONS

Multimorbidity was associated with sustained impairment IC among older Chinese adults. Compared to the metabolic pattern, both the arthritis-stomach and respiratory patterns exhibited a notably elevated risk of sustained impairment IC.