Management of hypertension in patients developing end-stage renal failure

Prevalence of reduced renal function among diabetic hypertensive patients

Patients with diabetes mellitus and hypertension are at high risk of vascular complications, particularly, renal deterioration. This study aimed to evaluate the prevalence and the risk factors of reduced renal function corresponding to chronic kidney disease (CKD) stages 3 - 5 among diabetic hypertensive patients. This is a retrospective cohort study of diabetic hypertensive patients attending A-Watani governmental medical center from August 2006 until August 2007. Creatinine clearance (CrCl) was estimated using the Cockcroft-Gault equation. Those with CrCl< 60 ml/ min, corresponding to CDK stages 3 - 5, were considered to have reduced renal function. The prevalence of reduced renal function was calculated, and the risk factors associated with it were evaluated using multiple logistic regression. The following were the results found in this study: (a) the prevalence of reduced renal function among the study patients was 35.5% distributed as follows: (63.5%) had stage 3 CKD, 21.7% had stage 4 and 13% had stage 5 CKD. (b) Patients with reduced renal function were elderly, had a higher number of chronic diseases and had a longer duration of diabetes and hypertension than those with CrCl≥ 60ml/ min. (c) Men had a higher prevalence of reduced renal function than women. (d) Significant predictors of reduced renal function were older age, duration of diabetes and the number of chronic diseases based on logistic regression analysis. Early and continuous screening of renal function among diabetic hypertensive patients is required to implement preventable strategies of end stage renal disease (ESRD). Better control of blood pressure and diabetes mellitus are important.

Treatment of resistant hypertension

Although the true prevalence of resistant hypertension is not known, it is likely that this condition will become increasingly common, driven by an aging population, obesity, nonadherence trends, and effects of target-organ disease. Current approaches focus on two goals: evaluation and correction of contributing causes, then selection of an effective drug regimen. Lifestyle factors contribute to resistance, particularly high sodium intake and weight gain. Secondary causes should be considered and corrected if feasible. Recent efforts have focused on the development of clinical pathways to guide treatment, based on plasma renin activity, aldosterone production, or hemodynamic measurements. The components of drug combinations beyond the second agent remain empiric. Although volume expansion plays a key role in drug resistance, clinical assessment of volume status is often difficult, frustrating efforts to achieve blood pressure control. Determination of the most effective approaches will require clinical trials using combination therapy.

Blood pressure control before and after starting dialysis

BACKGROUND/AIM

We have previously reported a study on the adequacy of management of hypertension in patients developing end-stage renal failure (ESRF) over a period of 3 years from a single health district in the UK (n = 107). There were significant shortcomings in all aspects of management of hypertension including blood pressure (BP) control.

METHODS

In this report, we have compared BP control in the same cohort of patients before and after starting renal replacement therapy (RRT).

RESULTS

BP control improved significantly after the patients were established on dialysis (mean 158/ 87 mm Hg pre-RRT vs. 152/82 mm Hg post-RRT; p < 0.0001), and fewer antihypertensive agents were prescribed to control BP (mean 2.45 vs. 1.74) in this period (p < 0.0001). Moreover, patients on continuous ambulatory peritoneal dialysis (n = 50) had a better systolic BP control compared with the haemodialysis patients (n = 57; p = 0.03).

CONCLUSIONS

This study shows significant improvement in BP control in a cohort of patients with ESRF following the start of dialysis.

Screening for chronic kidney disease: unresolved issues

End-stage renal disease is epidemic in the United States. As a measure to control this epidemic, it has been recommended that individuals who are at risk for CKD be tested for undetected kidney disease during routine health care encounters. There are generally accepted criteria against which screening recommendations for CKD control and prevention programs should be judged. If detection strategies are to be adopted for the screening of kidney disease, then CKD must represent a significant public health problem, be characterized by a clear natural history with a detectable asymptomatic period, outcomes should be improved by early treatment, and acceptable screening tests should be available. Health systems must provide adequate and appropriate follow-up medical care for individuals with newly detected CKD. Finally, the cost-effectiveness of screening needs to be demonstrated and the effectiveness of screening as a means of achieving reductions in CKD should be proven in randomized trials.

Cardiovascular disease in patients with chronic kidney disease

Cardiovascular disease (CVD) is the major cause of morbidity and mortality in patients with renal failure. Patients with chronic kidney disease have significant CVD, and carry a high cardiovascular burden by the time they commence renal replacement therapy (RRT). The severity of CVD that has been observed in dialysis patients lead to a growing body of research examining the pathogenesis and progression of CVD during the progression of chronic kidney disease (CKD) to end-stage renal disease (ESRD) (ie, predialysis phase). Multiple factors are involved in the development of CVD in CKD. More importantly, critical and key factors seem to develop early in the course of CKD, and result in preventable worsening of CVD in this patient population. Anemia is common in patients with CKD, and has been shown to have an independent role in the genesis of left ventricular hypertrophy (LVH) and subsequent CVD. Unfortunately, it is underdiagnosed and undertreated in patients with CKD. Early intervention, and better correction of anemia, seems to gain a great momentum in the prevention and management of CVD in CKD. Hypertension is another risk factor that has been targeted by the National Kidney Foundation Task Force on CVD in chronic kidney disease. This article reviews the different factors involved in the pathogenesis of CVD in CKD and the evidence supporting early and aggressive intervention.