Objective To examine the prevalence and the pattern of chronic disease comorbidity and the correlation among chronic disease comorbidity components among elderly residents in China and to provide evidences for developing treatment and prevention strategies and optimizing management of chronic disease comorbidities.

Methods We extracted the data on 11 707 community residents aged ≥ 60 years from China Health and Retirement Longitudinal Study (CHARLS) conducted in 28 province-level regions across China in 2015. The prevalence and pattern of chronic disease comorbidity among the elderly were analyzed and the correlation among chronic disease comorbidity components was estimated by calculating the relative risk ratio (RR) and the observed-to-expected ratio (O/E) of the comorbidy.

Results Among all the elderly, the prevalence rate of chronic disease comorbidity was 43.6% and totally 804 comorbid combinations of 14 chronic diseases (hypertension, dyslipidemia, diabetes or high blood sugar, cancer or malignant tumor, chronic lung diseases, liver disease, heart attack, stroke, kidney disease, stomach or other digestive disease, emotional/nervous or psychiatric problems, memory-related disease, arthritis or rheumatism, and asthma) were observed, with 76 kinds of dyad comorbidity and 169 kinds of triad comorbidity. For the 14 chronic diseases in the observed comorbidity combinations, following conditions are among the diseases with higher risk of comorbidity: asthma (RR = 31.77), stroke (RR = 22.60), heart disease (RR = 18.88), diabetes or elevated blood glucose (RR = 17.47), dyslipidemia (RR = 17.05), memory-related diseases (RR = 16.61), kidney disease (RR = 14.04), liver disease (RR = 13.46), and chronic lung disease (RR = 11.97). The results of correlation analysis revealed the dyad comorbidity with the highest O/E (162.15) was pulmonary disease plus asthma and the triad comorbidity with the highest O/E (10 287.72) was stroke plus emotional and mental illness plus memory related diseases.

Conclusion Asthma, stroke, heart disease, diabetes or high blood suga, dyslipidemia, memory-related disease, kidney disease, liver disease and chronic lung disease are the diseases with a higher risk of comorbidity among elderly residents in China and the diseases need to be concerned by clinic and public health professionals.