Background The incidence of chronic diseases is increasing, especially in rural areas, where younger patients often exhibit multimorbidity. Understanding multimorbidity in rural adults can guide the development of targeted management strategies for chronic diseases. Methods This cross-sectional study was conducted in rural North China using whole cluster stratified random sampling to select two counties in Shanxi Province. A total of 2,208 participants aged 30 years or older from 80 villages were enrolled, stratified by gender and age. Data collection involved questionnaires on socio-demographic characteristics, lifestyle, and disease history, along with physical measurements such as height, weight, and waist circumference. Results Among the 2,208 participants, 58.11% were aged 30-59 years, and 52.17% were female. The prevalence of chronic diseases was 66.53%, with a multimorbidity rate of 32.47%. The most common conditions were hypertension (43.21%), chronic digestive diseases (11.82%), and stroke (10.19%). Multimorbidity was more prevalent in those aged ≥60 years compared to the 30-59 age group (47.68% vs. 21.51%, P<0.05), with no significant gender differences. Hypertension was present in 78.52% of disease patterns, with common dyads being hypertension & stroke (7.47%), hypertension & heart disease (6.25%), and hypertension & diabetes mellitus (6.11%). In the 30-59 age group, hypertension & chronic digestive disease (3.82%) were most prevalent, while for those aged ≥60 years and males, hypertension & stroke were most common (12.65% and 9.47%, respectively). Among females, the most frequent dyad was hypertension & arthritis (8.16%). Conclusion Chronic diseases and multimorbidity are prevalent in rural North China, primarily driven by hypertension. Multimorbidity patterns differ by age and gender, indicating the need for targeted prevention and treatment strategies.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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Ethical approval was obtained from the Ethics Committee of Harbin Medical University (NO. HMUIRB2022005PRE), and all participants provided written informed consent.

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