Association of hypertension specialist treatment with blood pressure control in Japanese primary care: The J-DOME study.

Abstract

Although hypertension is a major contributor to cardiovascular complications, real-world blood pressure (BP) control in primary care and the role of hypertension specialists remain incompletely characterized. We evaluated BP control and associated factors using the Japan Medical Association Database of Clinical Medicine (J-DOME), a nationwide primary care registry. This cross-sectional study included patients with hypertension registered in 2024, categorized by treatment by specialists certified by the Japanese Society of Hypertension. Multivariable logistic regression identified factors associated with achieving office BP < 130/80 mmHg. Among 2663 patients (43.6% women; mean age, 71.4 years), 545 were treated by hypertension specialists. Mean BP was 134.4/74.8 mmHg, and the mean number of antihypertensive drugs was 1.6. Systolic BP was similar between specialist- and non-specialist-treated patients (135.1 vs. 134.2 mmHg; p = 0.28), whereas diastolic BP (76.1 vs. 74.5 mmHg; p = 0.0060) and the number of drugs (1.9 vs. 1.6; p < 0.0001) were higher in the specialist-treated group. Target BP achievement rate was lower in the specialist-treated group (30.8% vs. 37.3%; p = 0.0058), however, this difference was not observed among patients aged <75 years (33.2% vs. 35.4%; p = 0.55). The multivariable-adjusted model revealed that diabetes mellitus (odds ratio [OR], 1.32; 95% confidence interval [CI], 1.08-1.61) and a higher number of drugs (OR per additional drug, 1.12; 95% CI, 1.04-1.22) were associated with higher target achievement, whereas overweight (OR, 0.70; 95% CI, 0.58-0.85), obesity (OR, 0.57; 95% CI, 0.42-0.77), and specialist treatment (OR, 0.77; 95% CI, 0.61-0.96) were associated with lower achievement. Office BP control remains suboptimal in Japanese primary care. Lower achievement among specialist-treated patients despite more drugs may reflect the concentration of difficult-to-control hypertension in specialist care. Continued efforts to improve hypertension management, particularly in patients with obesity, are warranted.