Effect of a multidisciplinary clinic for the treatment of refractory hypertension.

To the Editor: Multiple reasons exist for hypertension to be resistant to medical therapy. Since multidisciplinary clinics have been shown to be effective for treating many chronic disorders, such as diabetes mellitus, heart failure, pain, asthma, rheumatoid arthritis, and HIV, (1,2) we created a multidisciplinary clinic dedicated exclusively to the treatment of refractory hypertension, defined as blood pressure >140/90 despite prescription of three antihypertensive medications. This clinic included a nutritionist, a pharmacist, an internist with expertise in hypertension, a nurse practitioner with expertise in hypertension, and a registered nurse.

Upon physician referral to the clinic, a nurse ordered a standard laboratory panel. Each patient was initially seen by a technician who took the patient's vital signs and administered an intake questionnaire with queries about over-the-counter medication use, salt intake, exercise frequency, smoking history, alcohol use, and screening questions for obstructive sleep apnea. A pharmacist then reviewed the patient's medications, addressed compliance, and counseled the patient on pharmacotherapy. Next, the patient was seen by a board certified internist/hypertension specialist. Medical records and lab work were reviewed and a focused history and physical examination was performed. Specific diagnostic and treatment recommendations were made. Next, a nutritionist discussed weight management, exercise and other lifestyle issues with the patient, to include a discussion of salt intake and the DASH diet. Finally, the clinic nurse reinforced the recommendations with the patient and scheduled a follow-up appointment.

We retrospectively reviewed referrals to the refractory hypertension clinic between February 2002 and March 2003. Of the 30 patients referred to the clinic, 10 were excluded from analysis: 3 were taking less than 3 antihypertensives, 3 were not hypertensive, 2 did not present for initial evaluation and 2 were lost to follow-up. For the 20 included patients, mean age was 67 years (range 41-91), the mean number of hypertension medications was 4.1 (range 3-6), and mean systolic and diastolic pressure were 163.8 mm Hg (SD 15.1) and 81.3 mm Hg (SD 15), respectively. The average duration of enrollment in the hypertension clinic was 134 days (range 14-282), and the patients were seen a mean of 4 times (range 2-9), with a mean follow-up interval of 34 days (range 7-74).

Enrollment in the refractory hypertension clinic was associated with a statistically significant decrease in systolic and diastolic blood pressure. Systolic blood pressure decreased 15.7 mm Hg (95% CI 5.6-25.8 mm Hg; P = 0.0041) and diastolic blood pressure decreased 6.6 mm Hg (95% CI 0.55-12.7; P = 0.03). While all patients had uncontrolled blood pressure upon enrollment; only 60% had uncontrolled blood pressure at their last clinic visit (95% CI 16-63.5; P = 0.002).

The mean number of antihypertensive medications per patient increased insignificantly: 0.2 medications per patient (range: -2 to 1; P = 0.3, paired t test). There was a significant increase in diuretic usage (70-100% of patients; P = 0.01), mostly via the use of spironolactone, and there was a significant decrease in the centrally acting alpha agonist clonidine (30-5% of patients, P = 0.021). There were no changes in average weight, smoking status, or reported alcohol consumption in our follow-up records. The lack of diuretic usage before enrollment in the clinic is notable and concerning; only 70% of the patients that presented to the refractory hypertension clinic were taking a diuretic--despite difficulty with blood pressure control. While this finding is concerning, it is consistent with data indicating that diuretics remain under-prescribed, (3) even though data suggests that diuretics are at least as effective as other medications in the treatment of hypertension and may be superior in the prevention of congestive heart failure among hypertensive patients. (4,5) The Joint National Committee on the Detection, Evaluation, and Treatment of High Blood Pressure (6) has recommended low-dose diuretics and beta blockers as initial therapy for the treatment of hypertension.

There are many possible reasons for the decrease in blood pressure; this improvement was probably mostly due to appropriate pharmacological treatment. Other potential reasons for improvement of hypertension control in this clinic include the effect of intensive attention to the disease process. Frequent visits, reinforcement of compliance by physicians, pharmacists, nurses, and nutritionists, and advice about diet and exercise may also have played a role.

This refractory hypertension clinic was effective in reducing systolic and diastolic blood pressure. This decrease occurred without an increase in the number of medications taken by the patients. Our data suggests that multidisciplinary clinics may be effective for the treatment of refractory hypertension.

Javed M. Nasir, BS

Steven J. Durning, MD

Kevin A. Dorrance, MD

G. Dodd Denton, MD, MPH

Uniformed Services

University of the Health Sciences

Bethesda, MD

References

1. Maislos M, Weisman D. Multidisciplinary approach to patients with poorly controlled type 2 diabetes mellitus: a prospective, randomized study. Acta Diabetol 2004;41:44-48.

2. Martineau P, Frenette M, Blais L, et al. Multidisciplinary outpatient congestive heart failure clinic: impact on hospital admissions and emergency room visits. Can J Cardiol 2004;20:1205-1211.

3. Psaty BM, Manolio TA, Smith NL, et al. Cardiovascular Health Study. Time trends in high blood pressure control and the use of antihypertensive medications in older adults: the Cardiovascular Health Study. Arch Intern Med 2002;162:2325-2332.

4. Psaty BM, Lumley T, Furberg CD, et al. Health outcomes associated with various antihypertensive therapies used as first-line agents: a network meta-analysis. JAMA 2003;289:2534-2544.

5. ALLHAT Officers and Coordinators for the ALLHAT Collaborative Research Group. The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial: Major outcomes in high-risk hypertensive patients randomized to angiotensin-converting enzyme inhibitor or calcium channel blocker vs diuretic: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). JAMA 2002;288:2981-2997.

6. Chobanian AV, Bakris GL, Black HR, et al, National Heart, Lung, and Blood Institute Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure; National High Blood Pressure Education Program Coordinating Committee. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 Report. JAMA 2003;289:2560-2572.