Discontinuation of Antihypertensive Therapy: Prevalence of Relapses and Predictors of Successful Withdrawal in a Hypertensive Community

Abstract

Antihypertensive therapy has been thought to be a life-long treatment. Nevertheless, antihypertensive medication may be discontinued in a substantial proportion of hypertensive patients at least for some time. The current study focused on predictors for the development of elevated blood pressure levels after discontinuation of antihypertensive drug therapy. In an open, prospective study, 88 white male patients with newly discovered essential hypertension (age 42 ± 7 years) were tested at baseline. Blood pressure was measured in various situations (at work, at rest, before and during treatment, and at follow-up), and the hemodynamic profile at rest and cardiovascular response patterns during stress tests were evaluated. Left ventricular mass and other cardiovascular risk factors were also carefully determined. After 6 months of strict blood pressure control ( < 140/90 mm Hg), they were treated by their primary care physician (mean duration of antihypertensive therapy 1.3 ± 1.7 years). After 6 years, 37 patients were still on antihypertensive therapy, but 19 of the 37 had blood pressure values ≧ 160/95 mm Hg. In 51 patients, therapy was discontinued: 29 were hypertensive, 15 were borderline hypertensive and 7 were normotensive. Relapse of hypertensive blood pressure in these 51 patients off therapy was predicted by resting blood pressure values before therapy (138 ± 11/91 ± 5 vs. 131 ± 11/85 ± 7 mm Hg, p < 0.05/0.01), cardiac output at rest (7.5 ± 1.9 vs. 6.2 ± 2.1 1/min, p < 0.05), total peripheral resistance (20 ± 9 vs. 14 ± 4 U, p < 0.05), increased heart rate during ergometry (50 ± 8 vs. 44 ± 6 b.p.m., p < 0.05) and left ventricular mass determined by echocardiography(212 ± 60 vs. 189 ± 44g, p < 0.01). There was no difference in age, blood pressure levels before and during treatment, the number of consultations with the primary care physician or cardiovascular risk factor profiles. In conclusion, intermittent rather than life-long antihypertensive treatment may be possible in hypertensive patients with low resting blood pressure, high cardiac output, low total peripheral resistance and low left ventricular mass.

Withdrawal of antihypertensive medication

“…Out of the 28 studies, 17 did not specify the type of AHT withdrawn [ 3 , 6 – 22 ]. The remaining studies withdrew angiotensin-converting enzyme inhibitors [ 23 ], angiotensin II receptor antagonists [ 24 ], clonidine [ 23 ], beta blockers [ 4 , 23 , 25 – 27 ], calcium channel blockers [ 23 , 24 , 28 ], diuretics [ 2 , 4 , 5 , 21 , 25 – 27 , 29 ], reserpine [ 21 ] or vasodilators [ 4 , 21 ]. The follow-up interval ranged from 10 weeks to 6 years.…”

“…The mean proportion of people successfully withdrawn from AHT (adjusted for sample size) was 0.38 at 6 months (95% CI 0.37–0.49; 912 participants) [ 6 , 8 , 17 , 19 , 21 , 22 , 24 , 25 , 29 ], 0.40 at 1 year (95% CI 0.40–0.40; 2640 participants) [ 5 – 7 , 9 – 12 , 14 – 18 , 22 , 24 – 28 ] and 0.26 at 2 years or longer (95% CI 0.26–0.27; 1262 participants) [ 6 , 7 , 10 , 13 , 20 – 23 , 25 – 29 ]. Figures 2 – 4 show the proportions and 95% CIs for each included study and the mean proportions (adjusted for sample size) and 95% CIs for 6 months, 1 and 2 years or longer after AHT withdrawal.…”

“…The studies investigated a total of 18 parameters including, sex, age, ethnicity, height, body weight, low-dose AHT or monotherapy, severity HT at 5–6 years previous to study, BP levels before withdrawal, duration AHT, lower sodium levels, lower corpuscular volume, higher serum albumin, baseline alcohol or cigarette use, history of vascular disease, baseline of left ventricular mass index, baseline ECG voltage and cardiovascular risk factors. Only five studies reported all variables included in the statistical analysis, significant predictors and appropriate statistics [ 8 , 12 , 16 , 23 , 29 ]. Based on the available evidence, a meta-analysis was not possible.…”

Twelve Month Follow-Up Audit of Nigerian Hypertensives on Back Titration

“…Apart from the age related metabolic changes proffered by Salako et al [6], some earlier workers had considered re-setting of the barostat mechanism [9]. It does appear that just like the disease hypertension itself is multifactorial, the mechanisms permitting dose reduction after a reasonable period of control are various [1]. It is known that peripheral arteries that maintain peripheral resistance are muscular, with the smooth muscle layer being significant [10].…”

“…The question of whether pharmacotherapy for systemic arterial hypertension should be life-long has continued to agitate the mind of care givers and patients alike. Whereas it is possible in some cases to reduce dose or discontinue drug(s) outright, relapse of high blood pressure is known to occur after some time [1]. All the same, the attitude of step down or outright discontinuation of anti-hypertensive pharmacotherapy appears to be safe provided close monitoring continued [2].…”