Korean J Intern Med.  2021 Jul;36(4):888-897. 10.3904/kjim.2019.361.

Apparent treatment-resistant hypertension among ambulatory hypertensive patients: a cross-sectional study from 13 general hospitals

• Kim S
• Park JJ
• Shin MS
• Kwak CH
• Lee BR
• Park SJ
• Lee HY
• Kim SH
• Kang SM
• Yoo BS
• Chung JW
• Choi SW
• Jo SH
• Shin J
• Choi DJ

• KMID: 2517805
• DOI: http://doi.org/10.3904/kjim.2019.361

Abstract

Background/Aims
To examine the prevalence and clinical characteristics of apparent treatment-resistant hypertension among ambulatory hypertensive patients.
Methods
We enrolled adult ambulatory hypertensive patients at 13 well-qualified general hospitals in Korea from January to June 2012. Apparent resistant hypertension was defined as an elevated blood pressure > 140/90 mmHg with the use of three antihypertensive agents, including diuretics, or ≥ 4 antihypertensives, regardless of the blood pressure. Controlled hypertension was defined as a blood pressure within the target using three antihypertensives, including diuretics.
Results
Among 16,915 hypertensive patients, 1,172 (6.9%) had controlled hypertension, and 1,514 (8.9%) had apparent treatment-resistant hypertension. Patients with apparent treatment-resistant hypertension had an earlier onset of hypertension (56.8 years vs. 58.8 years, p = 0.007) and higher body mass index (26.3 kg/m² vs. 24.9 kg/m², p < 0.001) than those with controlled hypertension. Drug compliance did not differ between groups. In the multivariable analysis, earlier onset of hypertension (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.97 to 0.99; p < 0.001) and the presence of comorbidities (OR, 2.06; 95% CI, 1.27 to 3.35; p < 0.001), such as diabetes mellitus, ischemic heart disease, heart failure, and chronic kidney disease, were independent predictors. Among the patients with apparent treatment-resistant hypertension, only 5.2% were receiving ≥ 2 antihypertensives at maximally tolerated doses.
Conclusions
Apparent treatment-resistant hypertension prevalence is 8.9% among ambulatory hypertensive patients in Korea. An earlier onset of hypertension and the presence of comorbidities are independent predictors. Optimization of medical treatment may reduce the rate of apparent treatment-resistant hypertension.

Keyword

Apparent treatment resistant hypertension; Prevalence; Characteristics; Independent predictor; Korea