Change In Antihypertensive Medication Research Articles

THERAPEUTIC RESISTANCE AS THE KEY DETERMINANT OF POOR BLOOD PRESSURE CONTROL IN HYPERTENSIVE PATIENTS: A STITCH SUBSTUDY: 4B.03

Objective: Despite impressive improvements in blood pressure control generally, control rates remain significantly lower than those achievable under optimal conditions, i.e., in clinical trials. Further, patients with diabetes and hypertension have control rates less than half of those without diabetes. The determinants of poor blood pressure control in the general population and in those with diabetes are unclear. Therefore we conducted a post hoc exploratory analysis to assess blood pressure control in patients from the STITCH study, a cluster randomized controlled trial of hypertension management strategies. Methods: Data were collected in 45 general practices, which enrolled patients with uncontrolled hypertension at trial entry. Pre test and post test blood pressure measurements were taken approximately 6 months apart. Antihypertensive medication changes throughout this follow-up period were documented. Of the 2104 hypertensive patients that were analyzed in the STITCH study, 320 had a diagnosis of diabetes. Results: Overall, 58% of the study population achieved target blood pressures. Through multivariate modeling it was identified that the addition of an antihypertensive drug was a significant predictor of blood pressure reduction. Notably, there were not significant differences in the intensity of treatment (1.7 vs. 1.9 standard doses), number of antihypertensive medications (1.9 drugs), or prescription of 3 or more drugs (26% vs. 31%), comparing those who did and did not reach target. Patients with diabetes were significantly less likely to reach target than those without diabetes (26% vs. 64%, p < 0.001). Notwithstanding, the antihypertensive therapy prescribed to patients with diabetes was only marginally more intensive than to those without diabetes (2.4 vs. 1.7 standard doses). Conclusions: In a community setting, there appears to be a ceiling on antihypertensive prescription regardless of whether target blood pressure is achieved. This ceiling effect is also apparent in patients with diabetes - patients in whom control rates lag far behind. These data suggest that therapeutic resistance and/or patient resistance to advancing therapy remains a very significant barrier to achieving blood pressure control.

Antihypertensive medication changes and blood pressure goal achievement in a managed care population

This study examined achievement of blood pressure (BP) goals, changes in antihypertensive therapy and reasons for these changes among adults with hypertension initiating angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs) or calcium channel blockers (CCBs). Claims data were examined for changes to medication regimens. Patient charts for 501 patients provided BP levels and reasons for changing medications. BP goal achievement was highest for initiators of ARBs (81.4%), compared with ACEIs (75.5%; P=NS) and CCBs (68.9%; P<0.01). Changes in antihypertensive therapy were least likely among ARB recipients (59.9%) compared with ACEIs (71.86%; P=0.02) and CCBs (74.85%; P<0.01). Failure to achieve BP goals was the most common reason for change in therapy (ARB, 32.9%; ACEI, 42.5%, P=NS; CCB, 47.9%, P<0.01). Although most patients achieved target BP goals, many required changes in treatment regimens. Initial choice of antihypertensive therapy may mitigate changes in therapies and better achieve BP goals.

Relative Plasma Volume Monitoring and Blood Pressure Control

Establishing dry weight in hemodialysis patients is an inexact science.1 Monitoring changes in blood pressure with volume removal is crude but can be effective in establishing dry weight. Unfortunately, probing for dry weight (eg, reduction of volume on dialysis sufficient to reduce blood pressure to <140/90 mm Hg) can lead to intradialytic hypotension, and this is more common in patients with large intradialytic weight gain. Often clinicians use medication-directed blood pressure control strategies in the hemodialysis patient.2 This paradoxically may interfere with the opportunity to achieve dry weight, because if the patient is on increased amounts of antihypertensive medication, more sizeable reductions in blood pressure with ultrafiltration may occur during dialysis.3 This would limit the opportunity for volume removal. As a consequence, the patient would then be chronically volume overloaded. If antihypertensive medication escalation results from inadequate achievement of goal blood pressure during dialysis, a vicious cycle would ensue. The net result is more risk of adverse events from medications and increased ventricular volume and pressure. Recurrent ventricular volume overload may be one of the most important factors leading to heart failure and increased risk of arrhythmia. Thus, …

Resolution of Systemic Hypertension after Laparoscopic Gastric Bypass

BackgroundHypertension is a well-recognized and treatable risk factor for coronary heart disease and is one of the most common comorbidities associated with obesity. The aim of this study was to characterize the clinical outcome of a cohort of patients with documented hypertension who underwent laparoscopic gastric bypass. MethodsNinety-five obese patients with documented hypertension and being treated with antihypertensive medication(s) underwent laparoscopic gastric bypass. Main outcome measures included length of hypertensive condition, changes in systolic and diastolic blood pressures, and changes in antihypertensive medication(s) at follow-up. ResultsThere were 69 (72%) females with a mean preoperative body mass index of 47 kg/m2. The mean duration of hypertension was 73 ± 70 months. The mean excess body weight loss at 12 months was 66%. The mean systolic blood pressure significantly decreased from 140 ± 17 mmHg preoperatively to 120 ± 18 mmHg at 12 months (p < 0.01). The mean diastolic blood pressure also significantly decreased from 80 ± 11 mmHg preoperatively to 71 ± 8 mmHg at 12 months (p < 0.01). At 12 months follow-up, 44 (46%) patients had complete resolution of hypertension while 18 (19%) patients had improvement. Patients with complete resolution had a shorter duration of disease as compared to patients without resolution (53 vs. 95 months, respectively, p = 0.01). ConclusionWeight loss associated with laparoscopic gastric bypass substantially improves and/or resolves hypertension in the majority of patients. Improvement of hypertension occurs as early as 1 month postoperatively and is more frequently in patients with a shorter preoperative duration of disease.

Role of Dietary Salt Intake in Posttransplant Hypertension With Tacrolimus-Based Immunosuppression

Dietary salt is an important contributor to hypertension in the general population. While its role in cyclosporine-induced hypertension is minimal, its role in tacrolimus-based immunosuppression has not been defined. We measured the 24-hour urine sodium excretion as an estimate of intake in a group of stable renal transplant recipients on tacrolimus ( N = 143) who had serum creatinine fluctuations <20% during the preceding 3 months. Average clinic-measured blood pressure (BP) from before and after the 24-hour urine collection was computed. Patients with recent changes in antihypertensive medications were excluded. Average systolic BP was 126 ± 14 and diastolic BP 76 ± 7 mm Hg. Urine sodium was 162.6 ± 70 mmol/d (range 50 to 351), and the sodium/creatinine ratio was 15.4 ± 6.4. There was no correlation between urine sodium excretion and either systolic or diastolic BP ( R = 0.07 and R = 0.05, P = NS) or the sodium/creatinine and systolic/diastolic BP ( R = 0.13, R = 0.11, P = NS). By multiple linear regression only weight and urine protein were independently associated with both systolic BP ( P < .0001 for each) and diastolic BP ( P < .05 for each). In conclusion, there is no appreciable influence of dietary salt intake on BP under tacrolimus-based immunosuppression. Restricting dietary salt intake in these patients cannot be recommended at the current time.

Cardiovascular Outcomes and Antihypertensive Drug Treatment in Older Women—Reply

To the Editor: The cohort study of cardiovascular outcomes and antihypertensive drug treatment by Dr Wassertheil-Smoller and colleagues used data from the Women’s Health Initiative Observational Study. We have a number of concerns that we believe limit drawing conclusions from this study. First, relative to the study sample size, the number of incident events was small and therefore the study may not have had adequate power to detect the end points in each subgroup (Tables 4 and 5 in the original article). For example, among women receiving a calcium channel blocker (CCB) plus an angiotensin-converting enzyme (ACE) inhibitor, only 8 cardiovascular deaths were reported. The P values for the overall comparison of therapies only reached borderline statistical significance for cardiovascular mortality, the outcome with the lowest annualized rates. Second, the confidence intervals reported for the hazard ratios in Tables 5 and 7 in the original article have not been adjusted for multiple comparisons, increasing the likelihood of a chance finding. Finally, the authors report the participants’ use of antihypertensive medications at baseline and in year 3 of follow-up, but did not account for changes in antihypertensive medications that likely occurred over time.

Endovascular repair of abdominal aortic aneurysms in patients with congenital renal vascular anomalies

Purpose: The endovascular repair of abdominal aortic aneurysms (AAAs) has been suggested as an alternative to conventional aortic reconstruction. The presence of anomalous renal vascular anatomy frequently necessitates special planning during conventional aortic replacement and may also create unique challenges for endovascular repair. We analyzed our experience with 24 patients with variant renal vascular anatomies who underwent treatment with aortic endografts to determine the safety and efficacy of this technique in this population. Methods: During a 6-year period, 204 patients underwent aortic endograft procedures, 24 (11.8%) of whom had variations in renal vascular anatomy. There were 19 men and five women. Each of the 24 patients had variant renal vascular anatomy , which was defined by the presence of multiple renal arteries (n = 32), with or without a renal parenchymal anomaly (horseshoe or solitary pelvic kidney). Twenty patients underwent aneurysm repair with balloon expandable polytetrafluoroethylene grafts, and the remaining patients underwent endograft placement with self-expanding attachment systems. Eighteen patients underwent exclusion and presumed thrombosis of anomalous renal branches to effectively attach the aortic endograft. The decision to sacrifice a supernumerary artery was made on the basis of the vessel size (<3 mm), the absence of coexisting renal insufficiency, and the expectation for successful aneurysm exclusion. Results: The successful exclusion of the AAAs was achieved in all the patients, with the loss of a total of 17 renal artery branches in 12 patients. Small segmental renal infarcts (<20%) were detected in only six of the 12 patients with follow-up computed tomographic scan results, despite angiographic evidence of vessel occlusion at the time of endografting. No evidence of new onset hypertension or changes in antihypertensive medication was seen in this group. No retrograde endoleaks were detected through the excluded renal branches on late follow-up computed tomographic scans. Serum creatinine levels before and after endografting were unchanged after the exclusion of the AAA in all but one patient with multiple renal branches. One patient had a transient rise in serum creatinine level presumed to be caused by contrast nephropathy. Conclusion: On the basis of this experience, we recommend the consideration of endovascular grafting for patients with AAAs and anomalous renal vessels when the main renal vascular anatomy can be preserved and when the loss of only small branches (<3 mm) is necessitated in patients with otherwise normal renal functions. (J Vasc Surg 1999;30:407-16.)

Hemodynamic Vertebrobasilar Insufficiency as an Adverse Effect of Antihypertensive Therapy

A 63-year-old white male with a 25-year history of hypertension experienced the onset of intermittent diplopia and gait disturbance 24 hours after a change in antihypertensive medication from atenolol 50 mg/d to enalapril 5 mg bid. Three weeks later, the patient was admitted with a worsening of symptoms. Cerebral arteriography revealed significant bilateral vertebral artery stenosis. Symptoms continued to progress in the hospital, and at the time of posterior circulation revascularization the patient had a persistent bilateral internuclear ophthalmoplegia and right ptosis. The need for a neurovascular workup and adjustment of therapy in patients with antihypertensive-associated cerebral ischemia is discussed.

Does Increasing Haemoglobin Concentration and Haematocrit Have a Pressor Effect in Dialysis Patients?

The haemodynamic consequences of differing rates of rise of haemoglobin and haematocrit in haemodialysis and CAPD patients were examined. Pre-dialysis mean arterial pressure, weight and haematological indices were recorded in 100 established haemodialysis patients prior to a 2-unit blood transfusion and repeated, pre-dialysis, within 1 week. Haemoglobin rose from 6.7 +/- 0.2 to 9.3 +/- 0.1 g/dl, weight was unchanged, and there was a small fall in mean arterial pressure. Similar indices were recorded, including the mid-arm circumference (MAC) in 100 CAPD patients 1 month after starting CAPD and at the time of maximum haemoglobin within the first year. Haemoglobin rose from 8.5 +/- 0.1 to 10.7 +/- 0.1 g/dl, weight increased slightly, but there was no change in MAC: weight ratio and there was a small fall in mean arterial pressure. In neither group was there a change in antihypertensive medication. In conclusion, increasing the haemoglobin concentration and haematocrit of dialysis patients within the range described in this study did not promote elevated blood pressure.

Course of blood pressure after cerebral infarction and transient ischemic attack

In 63 patients, admitted for cerebral infarction or transient ischemic attack (TIA), the blood pressure course was studied. The blood pressure before the event was studied retrospectively; 32 patients were normotensive, in 31 patients existed hypertension, with antihypertensive treatment in 15 of these cases. The blood pressure after the event was studied prospectively, and turned out to be risen in 67% of the patients on the day of admission. It fell in the first day after infarction or TIA, mainly on the second day, to a plateau level reached on the fifth day. Only 3 patients (5%) remained hypertensive until discharge from the hospital. In 48 patients blood pressure values were available as measured two to six months after discharge, without a change in antihypertensive medication. Blood pressure was increased compared to the value measured before discharge. In 14 patients (29%) hypertensive blood pressure figures were measured at that time. It is concluded that blood pressure is elevated in the acute phase of cerebral infarction and TIA, but falls spontaneously in the first days to normotensive levels in most patients; because blood pressure may increase again, measurements of blood pressure within the first months after discharge are needed.