关键词: 共病, 共病影响因素, 老龄化, 南北差异；Meta分析

Abstract: Background The comorbidity of multiple chronic diseases in the elderly has become an important issue that needs urgent attention in the field of public health. Therefore, it is of great significance to explore the influencing factors of multiple chronic diseases in the elderly. Objective To investigate the prevalence of multiple chronic diseases and related influencing factors in the elderly population in northern and southern China, in order to better manage and intervene the development and prognosis of multiple chronic diseases in the elderly in different regions. Methods PubMed, Embase, Web of Science, Cochrane Library, Scopus, China Biology Medicine Disc, China National Knowledge Infrastructure, Wanfang Data Knowledge service platform were searched for relevant studies on influencing factors of multiple chronic diseases in the elderly. Two researchers independently searched, screened, extracted data, and cross-checked, with a third party arbitrating disagreements. The search time limit was from the establishment of the database to July 2024. Stata 18.0 software was used for meta-analysis. Results The research incorporated 10 articles from the southern region and 10 from the northern region, with sample sizes of 2 342 507 and 75 871 cases, respectively. The prevalence of chronic comorbidities among elderly patients in the southern and northern regions was 34% [95% CI (29%, 38%),P < 0.001] and 36% [95% CI (22%, 50%),P < 0.001], respectively. Among them, the influencing factors of elderly patients with comorbidities in southern China were age [OR=1.92,95%CI（1.26，2.94）,P=0.003], gender [OR=1.51,95%CI（1.03，2.21）,P=0.034], and family monthly income per capita [OR=1.62,95%CI（1.03，2.54）,P=0.036], education level [OR=1.47,95%CI（1.25，1.73）,P＜0.001], body mass index [OR=1.72,95%CI（1.52，1.96）,P＜0.001], smoking [OR=1.53,95%CI（1.11，2.11）,P=0.009], drinking [OR=1.39,95%CI（1.26，1.54）, P＜0.001], regular physical [OR=0.67,95%CI（0.55，0.80）,P＜0.001]; Age [OR=1.67,95%CI（1.00，2.79）,P=0.048], body mass index [OR=2.12,95%CI（1.23，3.65）,P=0.007], drinking [OR=1.63,95%CI（1.32，2.02）,P＜0.001], regular physical exercise [OR=0.84,95%CI（0.71，0.99）,P＜0.037] were the influencing factors of elderly patients with multimorbidity in northern China. Sensitivity analysis showed that the results of Meta-analysis were stable, and Egger's test (comorbidity prevalence: P=0.826; influencing factors: P=0.841) suggested that the risk of publication bias of the included literature was not significant. Conclusions The prevalence of multimorbidity among the elderly is relatively high in both the northern and southern regions, influenced by age, body mass index, alcohol consumption, and physical activity in both areas. However, gender, monthly household income per capita, educational level, and smoking status are factors that specifically influence multimorbidity only among the elderly in the southern region. These disparities may stem from dietary habits, economic levels, lifestyle pace, and uneven medical resource distribution. Enhancing inter-regional medical resource coordination and sharing is advised to improve health equity and resource balance, boosting elderly health overall. Additionally, healthcare providers should tailor interventions based on these factors to optimize disease management in elderly with multimorbidity.

Key words: Multimorbidity, Influencing factors of multimorbidity, Aging, North-south differences；Meta-analysis