Hypertension-diabetes comorbidity in tropical Chinese adults

Hypertension-diabetes comorbidity (HDC) substantially increases the risk of cardiovascular and microvascular complications, yet population-based evidence from tropical island settings in China remains limited. This study estimated the prevalence of HDC among adults in Hainan Province and examined associated factors across sociodemographic, metabolic, and lifestyle domains.

We analysed data from the Hainan Province '2 + 3' health service package epidemiological survey, a population-based cross-sectional study conducted across all 24 administrative divisions from 3 November to 31 December 2022 using a two-stage disproportionate cluster sampling design. After prespecified data quality control and cleaning, 32 857 adults were included. Survey weights were applied to produce population-representative estimates, and survey-weighted multivariable logistic regression was used to identify factors associated with HDC.

The weighted prevalence of HDC was 7.0%, higher in men (8.0%) than women (6.0%), and increased sharply with age (1.6% in 18-39 years, 7.7% in 40-59 years, and 18.5% in ≥ 60 years). In the fully adjusted model, female sex was inversely associated with HDC (adjusted odds ratio (aOR) = 0.64; 95% confidence interval (CI) = 0.55-0.74), while older age (40-59 years: aOR = 5.42; 95% CI = 4.29-6.85), (≥ 60 years: aOR = 16.37; 95% CI = 13.38-20.04) and Li ethnicity (aOR = 1.60; 95% CI = 1.20-2.14) were associated with higher odds. Overweight (aOR = 1.83; 95% CI = 1.63-2.06), obesity (aOR = 2.68; 95% CI = 2.28-3.15), and dyslipidaemia (aOR = 1.74; 95% CI = 1.58-1.92) were independently associated with HDC, whereas underweight showed an inverse association (aOR = 0.67; 95% CI = 0.52-0.86). Among participants with self-reported diagnosed hypertension and diabetes, 66.8% reported taking any blood pressure control measure and 36.9% reported taking any blood glucose control measure, respectively.

In tropical China, HDC affects a substantial proportion of adults and is strongly associated with male sex, older age, excess adiposity, and dyslipidaemia. The low uptake of diabetes control measures among diagnosed individuals highlights the need to strengthen integrated screening, follow-up, and chronic disease management in this setting.