Biomedical subjects

W C Cushman

Publications and source records attributed to W C Cushman.

49 records · Page 3Linked to original sources

PubMed1992

Nonpharmacologic intervention to reduce blood pressure in older patients with mild hypertension.

BACKGROUND: Although nonpharmacologic interventions are widely recommended in the therapy of high blood pressure in older adults, surprisingly little data exist to confirm the efficacy of these interventions in older persons. METHODS: We conducted a randomized, controlled clinical trial in persons aged 60 to 85 years with a diastolic blood pressure of 85 to 100 mm Hg. The experimental arm was a nonpharmacologic intervention combining weight reduction, sodium restriction, and increased physical activity. The nonpharmacologic intervention consisted of eight weekly group and two individual sessions during the intensive phase, followed by four monthly group sessions during the maintenance phase. The control group received no treatment during the study. Blood pressure was assessed by certified technicians (blinded to group assignment) using random zero sphygmomanometers. RESULTS: Of 56 participants randomized, 47 completed the entire 6-month trial (21 in the intervention group and 26 in the control group). Attendance at the intervention sessions was excellent. The intervention group lost more weight (-2.1 kg) over 6 months than the control group (+0.3 kg). Trends for decreasing 24-hour urine sodium excretion in both the intervention and control groups, with greater trend in the intervention group, were not statistically significant. The intervention group experienced more reduction in systolic and diastolic blood pressure than did the control group (mean differences between groups at 6 months, 4.2/4.9 mm Hg, respectively). CONCLUSIONS: Our data indicate that a nonpharmacologic intervention will lower systolic and diastolic blood pressure levels in older people with borderline or mild elevations of diastolic blood pressure.

Aged↗

PubMed1991

Treatment of hypertension in the elderly. III. Response of isolated systolic hypertension to various doses of hydrochlorothiazide: results of a Department of Veterans Affairs cooperative study. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents.

In a double-blind randomized study, we evaluated the effects of 25 mg vs 50 mg of hydrochlorothiazide in 51 elderly patients (aged 68.9 +/- 7.0 years) with isolated systolic hypertension (blood pressure, 160 to 239 mm Hg systolic and less than 90 mm Hg diastolic). Dose levels could be increased to twice daily to control blood pressure. The reductions in blood pressure (25.4/6.8 mm Hg and 28.9/7.4 mm Hg) and proportion of patients in whom blood pressure was controlled (78% and 89%) were similar in the lower- and higher-dose groups during the titration phase. However, serum potassium level was reduced more in the higher-dosage (0.57 mmol/L) than the lower-dosage (0.17 mmol/L) group. There were no significant changes in blood pressure during a 24-week maintenance phase. No patient required withdrawal from the study because of adverse effects, and cognitive-behavioral function was well preserved. We conclude that hydrochlorothiazide is effective and well tolerated in older patients with isolated systolic hypertension, many of whom may be effectively treated with 25 mg of hydrochlorothiazide once daily.

Aged↗

PubMed1991

Chronic effect of KCl on black-white differences in plasma renin activity, aldosterone, and urinary electrolytes.

In a 10-week trial of the effect of 80 mEq KCl/day on blood pressure, the following biochemical changes were noted: plasma renin activity (PRA), originally significantly lower in blacks than whites, increased to the same level as whites after K supplementation. A similar trend was noted with aldosterone. KCl increased creatinine excretion in blacks and whites, and lowered Ca excretion in blacks. These results suggest that the low PRA found in blacks is due, at least in part, to low K intake, and not to genetic causes.

Adolescent↗

PubMed1990

Effect of back support and stethoscope head on seated blood pressure determinations.

Seated BP measurements were taken in 48 men with a history of essential hypertension: in a chair with back support v on an examining table with no back support, and with bell v diaphragm stethoscope head in each condition. There were no significant differences between bell and diaphragm in SBP or DBP determinations. SBP was not significantly different between table and chair, but table DBP was 6.5 mm Hg higher (P less than .0001) than chair DBP. We conclude that back support, but not bell v diaphragm stethoscope head, affects seated BP determinations.

Back↗

PubMed1990

Controlled trial of aerobic exercise in hypertension.

To determine the antihypertensive efficacy of aerobic exercise training in mild essential hypertension, a prospective randomized controlled trial was conducted comparing an aerobic exercise regimen to a placebo exercise regimen, with a crossover replication of the aerobic regimen in the placebo exercise group. The study took place in an outpatient research clinic in a university-affiliated Veterans Administration medical center. Twenty-seven men with untreated diastolic blood pressure (DBP) of 90-104 mm Hg were randomized to the two exercise regimens. Ten patients completed the aerobic regimen. Nine patients completed the control regimen, seven of whom subsequently entered and completed the aerobic regimen. The aerobic regimen consisted of walking, jogging, stationary bicycling, or any combination of these activities for 30 minutes, four times a week, at 65-80% maximal heart rate. The control regimen consisted of slow calisthenics and stretching for the same duration and frequency but maintaining less than 60% maximal heart rate. DBP decreased 9.6 +/- 4.7 mm Hg in the aerobic exercise group but increased 0.8 +/- 6.2 mm Hg in the placebo control exercise group (p = 0.02). Systolic blood pressure (SBP) decreased 6.4 +/- 9.1 mm Hg in the aerobic group and increased 0.9 +/- 9.7 mm Hg in the control group (p = 0.11). Subsequently, seven of the nine controls entered a treatment crossover and completed the aerobic regimen with significant reductions in both DBP (-6.1 +/- 3.2 mm Hg, p less than 0.01) and SBP (-8.1 +/- 5.7 mm Hg, p less than 0.01). BP changes were not associated with any significant changes in weight, body fat, urinary electrolytes, or resting heart rate. This randomized controlled trial provides evidence for the independent BP lowering effect of aerobic exercise in unmedicated mildly hypertensive men.

Adult↗

PubMed1990

Treatment of hypertension in the elderly: I. Blood pressure and clinical changes. Results of a Department of Veterans Affairs Cooperative Study.

We compared the efficacy and adverse effects of antihypertensive drug regimens in 690 men past age 60 with diastolic blood pressure 90-114 mm Hg and systolic blood pressure less than 240 mm Hg. They received either a low (25-50 mg) or high (50-100 mg) dose of hydrochlorothiazide daily. Of 644 patients who completed the hydrochlorothiazide titration, 375 (58.2%) were responders (diastolic blood pressure less than 90 and less than or equal to 5 mm Hg below baseline) and 92.8% of these completed a 6-month maintenance period. Blood pressure was reduced from 157.6/98.5 mm Hg by 18.3/9.5 mm Hg with low dose hydrochlorothiazide and by 20.4/9.6 mm Hg with high dose hydrochlorothiazide; more patients achieved goal blood pressure with the high dose. Whites and blacks responded equally. Serum potassium less than 3.5 mmol/l occurred in 104 of 321 (32.3%) of the high dose versus 62 of 333 (18.6%) of the low dose hydrochlorothiazide patients. The 269 nonresponders to hydrochlorothiazide were randomly assigned in a double-blind study to receive hydralazine, methyldopa, metoprolol, or reserpine in addition to hydrochlorothiazide; 79.2% responded to the addition of the second drug and 87.3% of these completed a 6-month maintenance phase. Overall, there were no significant efficacy differences among the step 2 regimens. We conclude that the lower dose of hydrochlorothiazide was nearly as effective as the higher dose, and the addition of a second drug was effective and generally well tolerated in elderly patients.

Aged↗

PubMed1990

Treatment of hypertension in the elderly: II. Cognitive and behavioral function. Results of a Department of Veterans Affairs Cooperative Study.

This study was designed to determine whether blood pressure reduction, per se, causes adverse effects on cognitive and behavioral function in elderly hypertensive patients. Men with mild-to-moderate diastolic hypertension who had passed their 60th birthday were entered into the trial. After a placebo washout period, they were assigned in a randomized, double-blind manner to one of two groups receiving hydrochlorothiazide (either 25 mg once or twice daily or 50 mg once or twice daily). Responders entered a 1-year maintenance period. Nonresponders were randomly assigned to double-blind treatment with hydralazine, methyldopa, metoprolol, or reserpine added to the diuretic therapy. During the placebo and treatment periods, patients underwent a battery of psychometric tests designed to assess cognitive function, motor skills, memory, and affect. A separate questionnaire assessed the patient's ability to perform activities of daily living. A subset of patients blindly being treated with placebo received the same battery of tests as a control for practice effect. The results showed that there was similar improvement on the psychometric tests between those patients whose blood pressure was successfully reduced and the placebo-treated control group. Therefore, the practice effect did not obscure a true deterioration in function. There were no substantive differences between the lower and higher doses of diuretic or among the four drugs added to the diuretic, although there were qualitative differences in side effects. We conclude that blood pressure reduction, per se, does not adversely affect cognitive and behavioral function in elderly hypertensive patients and that antihypertensive treatment is safe and effective in these patients.

Activities of Daily Living↗

PubMed1989

Captopril-associated acute interstitial nephritis.

A 57-year-old male with mild impairment of renal function secondary to diabetic glomerulosclerosis developed acute renal failure (creatinine 32.4 mg/dl) associated with a generalized desquamative skin rash and peripheral eosinophilia shortly after initiation of antihypertensive therapy with captopril. An acute interstitial nephritis was demonstrated on renal biopsy, and improvement was temporally related to initiation of therapy with prednisone. A review of the literature revealed 5 similar cases in whom acute deterioration of renal function occurred following initiation of captopril and in whom there were features of a hypersensitivity reaction, including skin rash, fever, eosinophilia, azotemia, eosinophiluria, and a Coombs-positive hemolytic anemia. Renal biopsy, where available, revealed an acute interstitial nephritis. Observations from these cases suggest that, of the angiotensin-converting enzyme inhibitors, this syndrome appears to be specific for captopril, begins within the 1st month of therapy, is not dose-dependent, and generally resolves on cessation of therapy. Steroids may hasten recovery, but sufficient data are not available to confirm their efficacy.

Acute Kidney Injury↗

PubMed1979

Response of arterial blood pressure, plasma renin activity and plasma aldosterone concentration to long-term administration of captopril in patients with severe, treatment-resistant malignant hypertension.

1. The response of arterial blood pressure, plasma renin activity and plasma aldosterone concentration to inhibition of angiotensin I converting enzyme (kininase II) with captopril has been studied in patients with severe, treatment-resistant, malignant hypertension. 2. Nine patients with a past history of severe hypertension, supine diastolic blood pressure greater than 120 mmHg before conventional antihypertensive therapy and resistant to conventional antihypertensive therapy were studied. 3. Captopril administration resulted in a marked decrease in arterial blood pressure and plasma aldosterone concentration and an increase in plasma renin activity. 4. Although arterial blood pressure remained significantly below the values observed during the control period, pressure did tend to increase again after 3 days. Addition of hydrochlorothiazide kept arterial pressure significantly below pretreatment control values.

Adult↗

PubMedDate not supplied

Alcohol consumption and hypertension.

Many observational studies have shown a relationship between three or more alcoholic drinks daily and hypertension. Reduction in alcohol intake is associated with lowering of blood pressure in randomized clinical trials: each drink per day reduction in intake lowers systolic and diastolic blood pressure by approximately 1 mm Hg. Although regular alcohol consumption seems to reduce the incidence of atherothrombotic cardiovascular events, excessive alcohol intake increases the risk of many medical and psychosocial problems. For persons with hypertension who drink excessively, average maximum alcohol intake of one drink per day in women and two drinks per day in men is a reasonable goal, if drinking is not otherwise contraindicated.

Alcohol Drinking↗

PubMedDate not supplied

Importance of potassium in cardiovascular disease.

The pivotal role of potassium (K+) in cardiovascular disease and the importance of preserving potassium balance have become clinical hot points, particularly as relates to new and emerging cardioprotective and renoprotective therapies that promote potassium retention. Although clinicians may be aware of the critical nature of this relationship, quite frequently there is some uncertainty as to the best way to monitor potassium levels in the face of a host of pathologic states and/or accompanying drug therapies that affect serum levels and/or total body potassium balance. Moreover, guidelines for monitoring of serum potassium levels are at best tentative and oftentimes are translated according to the level of concern of the respective physician. To address these uncertainties, an expert group was convened that included representatives from multiple disciplines. They attempted to reach consensus on the importance of K+ in hypertension, stroke, and arrhythmias as well as practical issues on maintaining K+ balance and avoiding K+ depletion. Because of the complexity of this topic, issues of hyperkalemia will be addressed in a forthcoming manuscript.

Cardiovascular Diseases↗

PubMedDate not supplied

Vasopressin elevation in essential hypertension and increased responsiveness to sodium intake.

The relationship of arterial pressure (AP) to plasma arginine vasopressin (AVP) and sodium (Na) intake was determined in untreated essential hypertensive (H) and normotensive (N) subjects. The AP of H subjects averaged 147/101 mm Hg and that of N subjects, 124/79 mm Hg. Plasma AVP was elevated significantly in H subjects, averaging 8.5 pg/ml compared to 4.7 pg/ml in N subjects. Multivariant regression analysis yielded a significant correlation (r2 = 0.34) between diastolic pressure, urine Na concentration, and changes in plasma AVP. Plasma Na of H subjects averaged 2.0 mEq/liter less and urine Na concentration 22 mEq/liter less than in N subjects. Sodium intake appeared to have no influence on the plasma AVP of N subjects, but H subjects excreting Na in excess of 250 mEq/day averaged a plasma AVP twice as high as that in H subjects excreting less than 150 mEq/day. In H subjects, the influence of Na intake appeared to be related to age. In subjects less than 50 years of age, Na intake did not appear to influence chronic levels of plasma AVP, while in subjects older than 50 years who were excreting Na in excess of 250 mEq/day, plasma AVP levels were twice (13.5 pg/ml) those observed in hypertensives of the same age excreting less than 150 mEq/ day (6.5 pg/ml). The data indicate that plasma AVP tends to be elevated in moderate essential hypertension. Reduced concentrating ability of the kidneys of these subjects is suggested by decreased urine Na concentrations despite elevated plasma AVP. The observed increases of plasma AVP could be exerting a direct influence on extra- and intravascular volumes by renal and systemic vasoconstriction.

Adult↗

PubMedDate not supplied

Nonpharmacologic approaches to therapy for hypertension.

OBJECTIVE: To provide an overview of nondrug therapeutic modalities for management of hypertension. METHODS: We review four strategies that involve lifestyle changes--weight reduction, moderation of sodium intake, physical activity, and moderation of alcohol consumption--that can potentially have a blood pressure-lowering effect. RESULTS: Several clinical trials have shown that a weight loss of 10 to 20% will significantly decrease blood pressure. An average of 1 to 2 mm Hg reduction in blood pressure may occur per kilogram of weight lost. Although sodium restriction has less effect on blood pressure than does weight reduction, a decrease in sodium intake to <100 mmol/day can yield a mean blood pressure reduction of 3 to 5 mm Hg systolic and 2 to 3 mm Hg diastolic. Exercise regimens have demonstrated convincing antihypertensive effects. In recent randomized studies, the average reduction in blood pressure ranged from 5 to 15 mm Hg for systolic measurements and 5 to 10 mm Hg for diastolic readings. Alcohol consumption has been shown to have one of the strongest associations with blood pressure among the potentially modifiable risk factors for hypertension. An average of 1 mm Hg decrease in blood pressure has been noted per one drink/day reduction in consumption. CONCLUSION: Lifestyle changes that can decrease blood pressure are important because they may not only eliminate the need for drug treatment but also decrease other cardiovascular risk factors.

Journal Article↗