Multimorbidity (having ≥2 chronic conditions within an individual) is a rapidly increasing problem particularly among hypertensive patients. This study compared the prevalence of hypertension and those with multimorbidity in three study populations.Design and Method:
We used cross-sectional data from three self-report surveys in China [N = 162,464], Scotland [N = 36,921], and Hong Kong [N = 29,187]. A consistent methodology was adopted to select representative samples of the household resident population of all ages by multi-stage stratified random sampling in each area. Chronic conditions were coded according to the International Classification of Diseases-10.Results:
Scotland showed the highest prevalence of self-reported hypertension (20.8% [n = 7,694]), followed by Hong Kong (11.0% [n = 3,206]) and China (9.6% [n = 15,675]). The proportion of people with multimorbidity among hypertension patients were 57.1% (95% confidence interval [95% CI] 55.9–58.3) in Scotland, 57.3% (95% CI 54.1–60.4) in China, and 60.8% (95% CI 59.1–62.5) in Hong Kong. Chronic conditions in musculoskeletal system, and endocrine and metabolic system were most common among all multimorbid subjects. Female, ageing, and smoking were independent factors associated with multimorbidity across the three study populations. There was a dramatic increase in the proportion of patients with multimorbidity among middle-aged adults (aged 45–64) in China. The prevalence of multimorbidity was higher in deprived population in both Scotland and Hong Kong, while in China multimorbidity was more slightly common among those living in more affluent households (adjusted odds ratio = 1.15, 95% CI 1.12–1.18).Conclusions:
All three study population had shared risk factors for multimorbidity. Unlike Scotland, both Hong Kong and China lack gate-keeper system, especially in China wherein social medical insurance coverage varies and individual's ability to pay for health care is dominant. The absence of a consistent source of care with high co-payments might reduce diagnosis and awareness of chronic diseases - and thus may contribute to the disparities in the prevalence of hypertension.