Objective To investigate the prevalence of chronic disease comorbidity among the elderly population in Jiangsu province to provide evidence for the development of chronic disease management strategies.

Methods A face-to-face survey was conducted among 21 344 residents aged ≥ 65 years recruited using stratified multistage cluster sampling from June to December 2021 in 12 districts/counties of six prefectures in Jiangsu province. A self-designed questionnaire and a brief cognitive impairment rating scale (Cog-12) developed by Chinese researchers were used in the survey. We analyzed the prevalence, prevalent types, and association rules of chronic comorbidity in the province's elderly population.

Results Of the 20 724 participants with valid responses, 9 759 (47.1%) were identified as having a chronic comorbidity. Of the observed cases of comorbidity, 3 947 (40.4%), 2 731 (28.0%), and 3 081 (31.6%) had two, three, and four or more chronic conditions, respectively. The top three binary chronic disease comorbidity patterns were hypertension combined with cognitive impairment (19.69%), arthritis (16.57%), and cerebrovascular disease (12.20%). In addition, the top three chronic disease comorbidity patterns were hypertension combined with arthritis and cognitive impairment (8.05%), cerebrovascular disease and cognitive impairment (6.48%), and heart disease and cognitive impairment (5.63%). The analysis of comorbidity association rules yielded 325 strong association rules (53 binary comorbidity association rules, 137 ternary comorbidity association rules, and 135 quaternary comorbidity association rules). Among these, heart disease was strongly associated with cerebrovascular disease, renal insufficiency, chronic lung disease, and hypertension. Cerebrovascular disease was strongly associated with renal insufficiency, cognitive impairment, and hypertension. Renal insufficiency was strongly associated with diabetes, arthritis, and hypertension. Chronic pulmonary disease was strongly associated with cognitive impairment and cerebrovascular disease.

Conclusion The prevalence of chronic comorbidity among the elderly in Jiangsu province is high. Hypertension combined with arthritis, cerebrovascular disease, and cognitive dysfunction are the most common comorbidity patterns among the elderly in this region.