Effects of income level on the association between hypertension and depression: 2010-2017 Korea national health and nutrition examination survey

Objectives: This study analyzed the associations of hypertension (HTN) with symptoms and diagnosis of depression by income level among Korean adults. Methods: This study was based on the 2010-2017 Korea National Health and Nutrition Examination Survey data; a total of 29 425 adults (aged 20 years or older) were analyzed. HTN was defined as a systolic blood pressure =140 mmHg, diastolic blood pressure =90 mmHg, or use of hypertensive medications. Depression symptoms were evaluated based on a questionnaire about depression-related symptoms. A depression diagnosis was defined based on questionnaire responses indicating that a participant had been diagnosed with depression. Household income was divided into higher or lower income ranges based on the median income of the participants. Multiple logistic regression analyses were performed to assess the associations between HTN and depression symptoms/diagnosis in the higher-income and lower-income groups. Results: In the higher-income group, the odds ratio (OR) for the association between HTN and depression symptoms was 1.15 (95% confidence interval [CI], 0.97 to 1.37), and the OR for the association between HTN and depression diagnosis was 1.41 (95% CI, 1.13 to 1.76). In the lower-income group, the OR for the association between HTN and depression symptoms was 1.18 (95% CI, 1.04 to 1.34), whereas the OR for the association between HTN and depression diagnosis was 0.82 (95% CI, 0.70 to 0.97). Conclusions: The associations of HTN with symptoms and diagnosis of depression differed by income level.