Temporal and geospatial trends of hypertension management in Korea: A nationwide study 2002-2016

Background and Objectives: Geographic distribution of hypertension management in Korea has never been reported. We investigated temporal and regional trends of hypertension management in Korea. Methods: For each calendar year from 2002 to 2016, we identified 2,423,245 to 7,549,989 persons aged ≥30 years treated for hypertension (total 80,564,109 cases). We calculated yearly age-sex standardized rates for medication adherence, combination therapy, blood test, and urine test according to geographic regions. We then used multivariate logistic regression to calculate odds ratios for hypertension management adjusted for individual-level sociodemographic factors. Results: Adherence rates have markedly increased from 24.4% (2002) to 71.6% (2016) nationwide. Regional difference was prominent in 2002 (highest, 31.7% in Seoul; lowest, 14.4% in Jeonbuk), but has become less noticeable over 15 years (highest, 73.1% in Daejeon; lowest, 69.0% in Jeonnam, 2016). Combination therapy rates increased from 42.8% (2002) to 61.0% (2011), but are in decreasing trend after 2011. Blood test rates were 58.8% in 2016, whereas urine test rates have been stagnant below 50% across all regions. Geographic variations of combination therapy and complication screening rates were not profound. Results from multivariable logistic regression, adjusted for age and sex, were in agreement with trends observed by standardized rates. The odds ratios remained unchanged when the models were further adjusted for employment status and household income. Conclusions: Regional difference in hypertension management was evident in the past, but has become less apparent over the last 15 years in Korea.