Therapy refractory hypertension in haemodialysis patients has become a rare indication for bilateral nephrectomy.

Abstract

In haemodialysis patients, blood pressure (BP) is usually plasma volume-dependent. Ultrafiltration during haemodialysis typically leads to reductions in plasma volume and body weight with a consequent lowering of elevated BP. However, in few cases, hypertension is refractory to reductions in plasma volume and to therapy with multiple antihypertensive drugs. In some patients, BP will increase even during volume depletion [1]. In these few patients, bilateral nephrectomy (BN) is an option for treatment [2]. We evaluated 16 haemodialysis patients [aged 37 (22–69) years, female 44%] in whom BN was performed due to severe or malignant hypertension with poor response to antihypertensive treatment (refractory hypertension). All patients were on haemodialysis in our dialysis centre during the years 1984–2008. Mean BP was significantly elevated even though the patients received ≥ 4 antihypertensive drugs. The aim of our retrospective study was to evaluate the efficacy and the frequency of needed BN. We compared BPs before and every 3 months following BN for an entire year. At 12 months after BN, mean systolic BP decreased from 194 ± 18 to 132 ± 12 mmHg, and diastolic BP decreased from 118 ± 10 to 82 ± 9 mmHg (P < 0.005). Near-normal BP values were observed within a mean of 2–3 months after BN. BP persistently decreased in 14 cases after nephrectomy, but rebounded in two cases because of hypervolaemia due to 10% body weight gain during intradialytic intervals. In these two cases, intensified ultrafiltration caused a prompt decrease in BP. In three subjects, hypotension occurred after BN (BP < 120/70 mmHg), and intradialytic ultrafiltration had to be decreased. Five patients required continuation of one antihypertensive drug. While in our centre, antihypertensive therapy was more intense during the last years of the study with 5.8 (5–6) daily antihypertensive agents compared with only 4.4 (4–5) in the years 1984–89 (NS). The clinical condition and quality of life improved in all of our patients. In nine patients, antihypertensive treatment was no longer necessary, and five patients required continuation of only one antihypertensive agent. Previous studies showed similar significant improvements in hypertension after BN [2], although a case report described persistent hypotension after BN in a 4-month-old infant [3]. According to the literature, BN is infrequently used as treatment for intractable hypertension. The prevalence of BN varies between 0% and 7% in most countries [4]. In our centre, refractory hypertension has become a rare indication for BN, and the incidence of BN was continuously decreasing during our observation period. For example, the incidence rate (n/year) decreased from 1.2 during the first five years (1984–89), to 1.0 and 0.4 during the next two 5-year periods, and was only 0.2 during 2003–08 (P < 0.05). The reduced frequency of BN was explained by the use of more effective antihypertensive medication during the last years; however, this difference was not significant because of small patient group sizes. Reductions in BN were also due to more frequent treatments with ACE inhibitors/AII blockers (9% in the first five years versus 33% during the last five years). In conclusion, we found that BN effectively lowered BP in cases that were extremely refractory to hypertension therapy. Despite this, the frequency of needed BN in haemodialysis patients appears to be decreasing. The lower frequency of BN may be associated with recent intensified antihypertensive therapy and a much greater use of ACE inhibitors during the last decade. Conflict of interest statement. None declared.