A comparison of standardized versus “usual” blood pressure measurements in hemodialysis patients

Journal of the American Society of Nephrology

Flynn

Pogue

et al. 2014

Self Cite

161

156

Hypertension is common, difficult to diagnose, and poorly controlled among patients with ESRD. However, controversy surrounds the diagnosis and treatment of hypertension. Here, we describe the diagnosis, epidemiology, and management of hypertension in dialysis patients, and examine the data sparking debate over appropriate methods for diagnosing and treating hypertension. Furthermore, we consider the issues uniquely related to hypertension in pediatric dialysis patients. Future clinical trials designed to clarify the controversial results discussed here should lead to the implementation of diagnostic and therapeutic techniques that improve long-term cardiovascular outcomes in patients with ESRD. Hypertension is common among patients with ESRD. In this review, we discuss the diagnosis, epidemiology, and management of hypertension among dialysis patients. We also review areas of existing controversies and briefly discuss the issue of hypertension in pediatric dialysis patients. EPIDEMIOLOGYThe prevalence, treatment, and control of hypertension among people on hemodialysis (HD) have used varying definitions to diagnose hypertension. The epidemiology differs based on how BP is measured: either before and after dialysis or using ambulatory BP recordings. Epidemiology with Routine BP MeasurementsThe prevalence of hypertension (defined as 1-week average predialysis systolic BP [SBP] measurements .150 mmHg or diastolic BP [DBP].85 mmHg or the use of antihypertensive medications) was 86% among 2535 clinically stable adult HD patients participating in a multicenter trial. 1 Among hypertensive patients, 12% did not receive antihypertensive drugs, 58% were treated but not controlled, and only 30% were controlled. The use of antihypertensive drugs has been reported to vary from 59% to 83%. [2][3][4][5] Furthermore, even among children on long-term HD, similar findings have been reported. 6 Several studies have confirmed greater antihypertensive drug use to be associated with poorer control. 7,8 It should be noted that antihypertensive drug use per se do not lead to worse BP control; in the absence of adequate volume control, increasing antihypertensive drug use may simply reflect difficult-to-control BP. Epidemiology Using Ambulatory BP MeasurementsThe prevalence of hypertension (defined by either a 44-hour interdialytic ambulatory BP of $135/85 mmHg or the prescription of any antihypertensive agent) was 86% among 369 chronic HD patients. 8 Although hypertension was being treated with antihypertensive drugs in 89% of patients, it was adequately controlled only in 38%. The independent determinants of poor control were the use of antihypertensive drugs and an expanded extracellular volume state. If patients were volume overloaded, nearly 80% became hypertensive when medications were Published online ahead of print. Publication date available at www.jasn.org.

Section: Diagnosismentioning

confidence: 96%

Assessment and Management of Hypertension in Patients on Dialysis

Journal of the American Society of Nephrology

Flynn

Pogue

et al. 2014

Self Cite

161

156

“…Standardized methods are those that use the recommended technique for BP measurement as described by Rahman et al (39); these methods were used in only seven studies (23,30,33,34,36,37,40), whereas others used "routine" measurements. The latter do not use a specified method for the measurement of BP.…”

Section: Qualitative Analysismentioning

confidence: 99%

Pre- and Postdialysis Blood Pressures Are Imprecise Estimates of Interdialytic Ambulatory Blood Pressure

Clinical Journal of the American Society of Nephrology

Peixoto

Santos

et al. 2006

213

154

H ypertension is perhaps one of the most pervasive problems of patients with ESRD. Although current guidelines that focus on cardiovascular disease in dialysis patients call for hypertension control as a top priority, the vast majority of patients who are on hemodialysis are hypertensive and control rates are poor (1). For practical reasons, BP assessment and antihypertensive treatment in patients with ESRD is performed on the basis of measurements that are made either immediately before or after dialysis. Such timehonored practice is widely accepted and formally recommended by clinical guidelines. The recent National Kidney Foundation Kidney Disease Outcomes Quality Initiative guidelines suggest that predialysis and postdialysis BP should be Ͻ140/90 and Ͻ130/80 mmHg, respectively (2).Population-based studies, including the recent Pressioni Arteriose Monitorate e Loro Associazioni (PAMELA) (3) and Ohasama studies (4) and studies on patients who had hypertension and were referred to a specialist clinic in the Dublin Outcome Study (5), have demonstrated clearly that ambulatory BP monitoring (ABPM) provides more accurate prognostic information than office BP, an issue that seems to be of particular relevance in the elderly. In a recent analysis of the ABPM substudy of the Systolic Hypertension in Europe (Syst-Eur) trial (6), ABPM and clinic BP did not identify the same patients for antihypertensive treatment, and ABPM was a better predictor of cardiovascular outcomes than clinic BP. These considerations are of relevance to patients with ESRD because uremia is a strong catalyst of the aging process and because patients with ESRD are older, with an average age of 60 yr.Given that the population with ESRD is elderly and the relationship between ABPM and cardiovascular outcomes and total mortality has scarcely been studied, we examined the magnitude of the difference between ABPM and pre/postdialysis BP. We hypothesized that if there were substantial differences, especially when differences between the two methods of measurements were unpredictable, then the two methods of measurement may have differing prognostic significance. The primary objective of this systematic analysis was to determine the magnitude of the difference and the variability in the difference between BP that is recorded in the dialysis environment, before and after the dialysis procedure, and ABPM that is performed simultaneously in the hemodialysis population. Materials and MethodsPublished studies that had reported paired ABP and pre/postdialysis BP in patients who were undergoing conventional three times a Published online ahead of print. Publication date available at www.cjasn.org.

“…BP that are obtained in the dialysis unit by technicians and nurses without attention to detail (routine BP) differ strikingly from BP that are obtained using standard methods. Nearly half of the SBP are Ͼ10 mmHg different from routine BP when standard methods of measurements are used (8). Higher ambulatory BP recordings are associated with increased mortality in HD patients (9).…”

mentioning

confidence: 99%

Home Blood Pressures Are of Greater Prognostic Value than Hemodialysis Unit Recordings

Alborzi

Patel

Clinical Journal of the American Society of Nephrology

2007

224

193

Background and objectives: Although ambulatory BP recordings are found to be superior to dialysis unit recordings in predicting outcomes, ambulatory BP are difficult to obtain in the day-to-day treatment of hemodialysis patients. Home BP agree well with ambulatory BP, but the prognostic significance of home BP recordings is unknown in hemodialysis patients. This study ascertained the role of home BP in predicting all-cause and cardiovascular mortality.Design, setting, participants, & measurements: A prospective cohort study was conducted in 150 patients who were on chronic hemodialysis dialyzing at four university-affiliated units. BP was self-measured at home for 1 wk, for an interdialytic interval by ambulatory recording, and by "routine" and standardized methods in the dialysis unit for 2 wk. Patients were followed for a median of 24 mo to assess the end points of all-cause and cardiovascular mortality.Results