Resistant hypertension revisited: a comparison of two university-based cohorts.

BACKGROUND: More than a decade ago, we found that a suboptimal medication regimen was the leading cause of resistant hypertension (RH) among patients referred to a tertiary care clinic. Since then, lower blood pressure (BP) goals have been recommended, suggesting that more patients may have RH. To assess whether the reasons for and treatment of RH have changed, we determined the frequency of various causes of resistance, the proportion of patients achieving goal BP, and the changes made in antihypertensive regimens. METHODS: The charts of all new patients seen at the RUSH University Hypertension Center between January 1, 1993, and November 1, 2001, were reviewed for strict criteria for RH: 1) physician referral for uncontrolled hypertension; 2) BP > or =140/90 mmHg despite use of three antihypertensive drugs; and 3) at least one follow-up visit. Patients were followed-up until goal BP was achieved on two consecutive visits or their last visit or until March 2002. RESULTS: Of 1281 patients, 141 met criteria for RH. A cause of resistance was found in 94% of cases, including the following: drug-related causes (58%); nonadherence (16%); psychological causes (9%); office resistance (ie, in-clinic BP readings that were higher than goal despite treatment with antihypertensive medications and despite normotensive BP outside of the clinic as demonstrated by 24-h ambulatory BP monitoring) (6%); and secondary hypertension (5%). Overall, 53% of patients had their BP controlled to <140/90 mmHg, largely from regimen optimization and intensification, proper use of diuretics, and on average 4.1 +/- 1 antihypertensive medications (3.7 +/- 0.9 on referral). CONCLUSIONS: These data are strikingly similar to those from our previous study of RH, in which a suboptimal medication regimen was the most common reason for resistance. Goal BP was most commonly achieved after optimizing the diuretic regimen and increasing the number of medications, suggesting that physicians should use these measures to attain the recommended lower BP goals If goal BP is not reached, referral to a clinical hypertension specialist may be appropriate.

Effect of fixed-dose ACE-inhibitor/calcium channel blocker combination therapy vs. ACE-inhibitor monotherapy on arterial compliance in hypertensive patients with type 2 diabetes.

Assessment of vascular compliance may be a useful measurement of the clinical effects of antihypertensive treatment. Both angiotensin-converting enzyme (ACE) inhibitors and calcium channel blockers are known to improve vascular elasticity. A study was performed to test the hypothesis that combined therapy with an ACE inhibitor and a calcium channel blocker would have additive benefits on vascular compliance at similar levels of blood pressure (BP), as compared with monotherapy with an ACE inhibitor. This 12-week, double-blind study was a substudy of a larger clinical hypertension study conducted in patients with hypertension and type 2 diabetes. Subjects (N = 20) were randomized to either a fixed-dose combination of amlodipine besylate/benazepril HCl or to enalapril monotherapy. BP, heart rate, large- and small-vessel compliance, systemic vascular resistance, and urinary microalbumin excretion were assessed at baseline and after treatment. Both treatments were similarly effective in lowering BP, reducing systemic vascular resistance, and decreasing urinary microalbumin excretion. Improvement in large-vessel compliance was significantly greater among subjects who received ACE-inhibitor/calcium channel blocker combination therapy (52%) as compared with those who received ACE-inhibitor monotherapy (32%; p < 0.05). No significant change in small-vessel compliance was observed with either treatment. Greater improvement in large-vessel compliance with combination therapy was independent of BP lowering.

The clinical performance and ease of use of a blood glucose meter that uses a 10-test disk.

Patient and health care provider evaluations are critical in establishing the accuracy and usability of new blood glucose meter systems. The objective of our study was to evaluate the clinical performance and ease of use of a blood glucose meter that uses a 10-test disk (Ascensia Breeze meter system, Bayer Healthcare LLC, Elkhart, IN). Meter capillary blood glucose results were compared with laboratory glucose results from 100 subjects with diabetes at two diabetes centers. Five health care professionals also tested subject blood samples. The subjects completed a questionnaire rating the ease of use of the meter, and their ability to learn to use the meter was also evaluated. Analytical accuracy of the meter system was assessed using ISO 15197:2003 performance criteria. Subject and health care professional meter glucose results were within 20% of laboratory glucose results [or 15 mg/dL (0.83 mmol/L) for specimens with less than 75 mg/dL (4.17 mmol/L) glucose levels] for 93.4% and 94.4% of results, respectively. Clinical accuracy of the system was evaluated using Parkes error grid analysis. The error grid analyses showed that 100% of subject and health care professional meter blood glucose results were in Zones A (92%) and B (8%). In the ease-of-use questionnaire, 91% of subject ratings of the meter were favorable. Subjects learned to operate the meter properly using the meter instructional material with little or no assistance from the health care professionals. The 10-test disk was rated as a prominent favorable feature. The new meter was accurate and precise in the hands of subjects with diabetes and health care professionals. Subjects found the meter easy and intuitive to learn to use. The study subjects were able to correctly use the meter after independently reviewing the user guide.

Effects of COX inhibition on blood pressure and kidney function in ACE inhibitor-treated blacks and hispanics.

Cyclo-oxygenase (COX) inhibitors attenuate the antihypertensive effects of angiotensin-converting enzyme (ACE) inhibitors and reduce kidney function. The study tests the hypothesis that these two classes of drugs have similar effects on glomerular filtration rate (GFR) and 24-hour blood pressure. The primary endpoint was change in 24-hour systolic blood pressure. Using a randomized crossover design, 25 black and Hispanic hypertensive participants (mean age 58+/-3 years) with osteoarthritis were studied. All participants received an ACE inhibitor at baseline. Once systolic blood pressure was <140 mm Hg, either celecoxib 200 mg/d or diclofenac 75 mg twice daily for 4 weeks was started. After measurements were obtained, all participants underwent a 2-week washout period and crossed over to the other drug for 4 weeks. A significant difference in mean 24-hour systolic blood pressure was noted between groups at 4 weeks (+4.1+/-1.1 mm Hg diclofenac versus +0.6+/-0.6 mm Hg celecoxib; P=0.01). However, because celecoxib has duration of action shorter than 24 hours, we compared ambulatory values at celecoxib trough and peak activities. At peak, no difference in systolic blood pressure was noted between agents (+3.6+/-0.04 mm Hg diclofenac versus +4.2+/-1.9 mm Hg celecoxib; P=0.67). GFR was also differentially affected at 24 hours (-9.9+/-2.4 mL/min diclofenac versus -0.4+/-1.2 mL/min celecoxib; P=0.01). We conclude that diclofenac and celecoxib increase systolic blood pressure at peak levels; however, these agents differ in their 24-hour effects. Differences observed in blood pressure response between COX inhibitors may not be related in their sensitivity but rather their dosing frequency.