The relationship of plasma norepinephrine levels and aortic distensibility in elderly with isolated systolic hypertension.

The present study evaluated the relationship of plasma norepinephrine (NE) and aortic distensibility (AOD) in a group of elderly patients with isolated systolic hypertension. Aortic distensibility was calculated as AOD = 2 x (delta aortic diameter)/diastolic aortic diameter) x (delta aortic pressure). Results indicate that the aortic diameters were significantly increased while the diastolic blood pressure and heart rate were decreased, in response to combined alpha- and beta-receptor blockade (labetalol). However, we found that AOD was not significantly related to plasma NE. We therefore conclude that AOD can be increased in elderly hypertensives by alpha-beta-blockade, as has been found in younger patients, but plasma NE is not a useful marker for AOD in this population.

Uremic small artery disease: calciphylaxis with penis involvement.

Two male patients with chronic renal failure maintained on hemodialysis developed progressive clinical features of ischemic necrosis (so called calciphylaxis) of their extremities and penis. Both patients died. In one patient, penectomy provided tissue for histopathologic examination and there were changes of small artery calcification. A role of iron overload on the production of calciphylaxis is reviewed. This report is perhaps the first in nephrology literature on the occurrence of calciphylaxis involving penis and prepuce.

Effectiveness and tolerability of once versus twice daily nitrendipine in the treatment of mild to moderate hypertension. The Canadian Nitrendipine Study Group.

Improved measurement of plasma concentrations of nitrendipine demonstrates a plasma half-life of 17 to 21 h allowing once daily dosing for antihypertensive treatment. To determine the effectiveness and tolerability of nitrendipine given once versus twice daily, 78 patients with mild to moderate essential hypertension were randomized in a double-blind fashion to 12 weeks of treatment with either nitrendipine 20 mg once daily (n = 39) or nitrendipine 10 mg bid (n = 39). Blood pressures measured at the end of the dosing interval were similar on 20 mg once daily and 10 mg bid. Adverse events considered to be drug related (flushing and headaches) occurred mostly at the beginning of active treatment and more frequently on the once daily dosing, resulting in a greater number of patients being withdrawn from the once daily treatment group. Thus, nitrendipine 20 mg once daily lowered blood pressure as effectively as 10 mg bid but was associated with a higher incidence of adverse events. These could be minimized by starting at nitrendipine 10 mg once daily and increasing to 20 mg once daily after two to four weeks.

Patterns of compliance with once versus twice daily antihypertensive drug therapy in primary care: a randomized clinical trial using electronic monitoring.

OBJECTIVE: To evaluate patterns of compliance with once versus twice daily administration of antihypertensive therapy (primary-outcome measure) and relevance of partial compliance for blood pressure control (secondary outcome measure). DESIGN: Multicentre, nonblinded, parallel group randomized design. SETTING: Nonacademic primary care practices across Canada. STUDY POPULATION: Patients with mild essential hypertension (diastolic blood pressure 95 to 110 mmHg) of either sex (40% women), age 18 to 80 years (average 55 years). One hundred and ninety-eight patients were randomized to active treatment; 14 patients discontinued the study because of side effects. INTERVENTIONS: After a four-week placebo run-in period, patients were randomized to amlodipine 5 mg once-a-day or diltiazem slow release formulation (SR) 90 mg twice daily. Doses were increased to 10 mg and 180 mg to achieve sitting diastolic blood pressure of 90 mmHg or less. OUTCOME MEASURE: During 20 weeks on active treatment, compliance was assessed by pill counts and medication event monitoring system (MEMS), assessing percentage of prescribed doses taken, percentage days correct doses taken, percentage prescribed doses taken on time and blood pressure control as determined by office blood pressure measurement. RESULTS: The percentage prescribed doses taken (by either pill count of MEMS) showed a high degree of compliance, similar for the two treatments. However, other parameters of compliance were significantly better with once versus twice daily therapy. Partial compliance (less than 80% by pill count) led to less blood pressure control with the short acting diltiazem, but did not affect blood pressure control for the long acting amlodipine. Side effects profiles did not differ between the two treatments. CONCLUSIONS: Within the constraints of a clinical trial, hypertensive patients in primary care show a high degree of overall compliance with once or twice daily pill-taking, but patterns of pill-taking are more erratic with twice versus once daily medication, particularly in men. The results suggest that the negative consequences of partial compliance for blood pressure control can be offset by choosing agents with a duration of action well beyond the dosing interval.

Drug-induced acute interstitial nephritis: report of 10 cases.

Between January 1979 and June 1985, 10 patients with acute allergic interstitial nephritis were seen in a clinical nephrology service at a large regional hospital. The onset of renal failure was temporally related to the use of a drug: a nonsteroidal anti-inflammatory agent (NSAID) (in four patients), cimetidine (in three), antibiotics (in two) or allopurinol (in one). The onset of renal failure was acute in three patients and insidious in seven. Two patients also exhibited marked proteinuria. Clinical features such as fever, rash, hematuria, pyuria with or without eosinophiluria, and mild to marked proteinuria had led to suspicion of the disease. The diagnosis was confirmed by renal biopsy findings of inflammatory cells, predominantly lymphocytes, plasma cells and eosinophils. Three patients required hemodialysis; two of them received steroids as well. Steroid therapy was also used in two patients with NSAID-induced proteinuria. Renal function improved in nine patients by 35 days, but one patient continued to have slow but progressive deterioration of renal function. Acute interstitial nephritis can be distinguished from other forms of acute renal failure by heavy renal uptake of gallium 67, maximal 48 hours or more after injection. The improvement in renal function after discontinuation of the implicated drug, the characteristic histopathological findings of allergic interstitial nephritis, and the presence of eosinophils and sometimes IgE in the blood suggest a hypersensitivity reaction.

Diagnostic indices in acute renal failure.

The urine/plasma creatinine ratio (U/P Cr), the urine sodium concentration (UNa), and the diuretic response to mannitol infusion in 23 patients were reviewed in an attempt to differentiate functional renal failure (FRF) from acute tubular necrosis (ATN). FRF was diagnosed if the plasma urea nitrogen (PUN) or serum creatinine stabilized within 72 hours. When renal failure persisted longer, patients had ATN. Subjects dying within 72 hours were excluded. Ten patients had ATN and five survived. The minimum duration of renal failure among survivors was 10 days. None responded to mannitol. Of 13 patients with FRF, 11 survived. Seven of 12 who received mannitol responded with a diuresis. The mean UNa in the patients with ATN was 51.4 mEq./1. +/- 9.48 (SE). The mean U/P Cr was 11.2 +/- 1.12. In patients with FRF, the mean UNa was 14.0 mEq./1. +/- 4.2 and the mean U/P Cr was 42.5 +/- 11.5. A significant overlap was present between the two groups. When UNa was factored by the U/P Cr, the resultant ratio was significantly different for the two groups of patients (P < 0.01), and this proved to be a useful clinical index with which to distinguish FRF from established ATN.

A large regional hospital's experience with treatment of end-stage renal disease.

During the first 10 years of the treatment program for end-stage renal disease at the Saint John (New Brunswick) Regional Hospital 164 adults were treated by hemodialysis (with or without renal transplantation, performed outside of the province) or peritoneal dialysis. The primary causes of renal disease were not significantly different in men and women except for glomerulonephritis, which was twice as common in men as in women. Life-table analysis showed that the younger transplant recipients had the highest survival rate, but that the prognosis was almost as good among the much older patients who received continuous ambulatory peritoneal dialysis. Probably because they tended to be younger and their renal disease was caused by less threatening conditions, men survived longer than women. The survival rates were significantly related to the primary cause of the renal disease; patients with diabetes or systemic disease had the worst prognosis. Overall, these results compare well with those obtained in major university centres.

Blood pressure: distribution in students of junior and senior high schools in Saint John, NB.

Blood pressures were recorded for 8950 students (82.4% of the total student population) of the junior high and high schools of Saint John, NB. Among the boys the mean systolic pressure rose from 104 mm Hg at age 12 to 117 mm Hg at age 18; among the girls the rise was from 105 to 110 mm Hg. The mean diastolic pressure also rose, from 61 to 67 mm Hg, in both sexes. These data are similar to those found in epidemiologic studies in Montreal and Bogalusa, Louisiana. However, the mean systolic values are lower by 10 mm Hg than those in an Edmonton study and the norms published by a United States task force. Recording methods could explain some of the observed differences, but population differences may also contribute. The discrepancies suggest that the current standards for children and adolescents need to be reassessed.

Swelling of olecranon bursa in uremic patients receiving hemodialysis.

Three patients with chronic renal failure who received therapy with hemodialysis through arteriovenous fistulas in the forearm had fluctuating swelling over the elbow on the same side as the fistula used for the dialysis. The clinical findings in each case were compatible with olecranon bursitis with effusion. The aspirate obtained from the swellings contained lymphocytes, polymorphonuclear leukocytes and histiocytes, a finding similar to that in cases of uremic pericardial and pleural effusion. Biopsy of the bursa in one case showed hyalinized collagenous tissue with infiltration by histiocytes and lymphocytes, reflecting underlying chronic inflammation. Uremia was believed to be the causative factor. Bursitis with effusion is considered to be one of the clinical aspects of uremic polyserositis.