Resistant hypertension in a tertiary care clinic: revisited

Resistant hypertension (RHTN) is probably the most common reason for referral to hypertension specialist clinics. To determine the prevalence and evaluate the etiologies of RHTN, as well as evaluate the impact of the HTN specialist to achieve goals set forth by JNC VI. Review of clinic records of all patients seen for the first time between 1/1/93 and 3/31/98 using similar criteria and methods to our earlier study (Yakovlevitch & Black, 1991). Records of all patients who met inclusion criteria for RHTN (≥3 antihypertensive medications and a BP ≥ 140/90 mmHg) were evaluated. Demographic data, medical history, physical exam findings, and lab results were recorded. Specific attention was given to the HTN history including anti-hypertensive regimen prior to and after being seen at the clinic, side effects, compliance, and other factors that may be considered to be responsible for their RHTN. Of the 568 charts reviewed, 65 (11%) met our study criteria for RHTN. As in our prior study, the most common cause was a suboptimal regimen (23 patients). Unexpected secondary hypertension accounted for 11%, similar to our previous study. Obesity (BMI ≥ 27) was a significant factor in this cohort and was found in 51 (78%) of patients. BP control, defined as BP ≤ 140/90 mmHg, on 2 consecutive visits, was achieved in 34 (52%) of patients. Another 11 (17%) had significant improvement in their blood pressure (≥15% decrease in DBP). The most common change made in the antihypertensive regimen involved switching to fixed-dose combinations. Most patients were already on diuretics, ACE inhibitors and/or calcium antagonists. A suboptimal medication regimen is the most common cause of RHTN. Hypertension specialists were successfully able to control or induce significant improvement in BP in approximately 70% of those referred to a specialist clinic. This supports the recommendations of JNC VI and BHS to refer to the HTN specialist.