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BACKGROUND: The 1988 US National Cholesterol Education Program Expert Panel Report recommended initial treatment with niacin or bile acid sequestrants, followed by other agents if needed, to lower low-density lipoprotein cholesterol (LDL-C) levels in hypercholesterolemic patients who require drug therapy. It is unknown how the effectiveness and costs of such an approach ("stepped care") compare in typical clinical practice to those of initial therapy with lovastatin. PATIENTS AND METHODS: We randomly assigned 612 patients, aged 20 to 70 years, who met 1988 National Cholesterol Education Program guidelines for drug treatment of elevated LDL-C level and had not previously used cholesterol-lowering medication, to either a stepped-care regimen or initial therapy with lovastatin (both n=306). The study, conducted at Southern California Kaiser Permanente, was designed to approximate typical practice: provider compliance with treatment plans was encouraged but not enforced, and patients paid for medication as they customarily would. RESULTS: At 1 year, the decline in mean LDL-C level was significantly greater among patients assigned to initial treatment with lovastatin (22% vs 15% for stepped care; P<.001), as was the number who attained goal LDL-C level (

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To compare the effectiveness and costs of two alternative approaches to the treatment of hypercholesterolemia, a prospective randomized trial is being undertaken at Southern California Kaiser Permanente, a large health maintenance organization. Six hundred and twelve patients with postdiet LDL cholesterol (LDL-C) levels in the range of 190-230 mg/dl (or 160-230 mg/dl for those with coronary heart disease or two or more coronary risk factors) were randomized to a stepped-care regimen (initial treatment with niacin followed by other agents if needed) or to initial use of lovastatin, an HMG-CoA reductase inhibitor. All patients are being followed for 1 year. The study seeks to approximate conditions of typical clinical practice: provider compliance with these plans of treatment is encouraged but not enforced and patients pay for medication as they customarily would. Principal outcomes of interest include the proportion of participants who achieve goal LDL-C at one year, the mean change in total cholesterol and LDL-C levels between baseline and the end of follow-up, and the costs of cholesterol-lowering therapy.

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A diabetic patient was treated with a somatostatin analogue, SMS 201-995, to control chronic diarrhea and orthostatic hypotension. The patient was injected with 50 micrograms, 100 micrograms, and 150 micrograms of SMS 201-995 subcutaneously twice daily for three days at each dose. Stool weight decreased from a basal mean value of 906 g per 24 hours to 628 g, 445 g, and 408 g per 24 hours, respectively. Diarrhea remained suppressed for 18 months when the patient was last seen. When SMS 201-995 was then given at 5 micrograms to 10 micrograms per hour by continuous subcutaneous infusion, stool weight decreased to a mean of 321 g per 24 hours. Basal blood pressure, which averaged 99/71 mm Hg, rose to 133/91 mm Hg five minutes after 75 micrograms of SMS 201-995 was injected subcutaneously; it remained elevated for six hours after injection. Serum motilin levels decreased significantly from 126 pg/ml before injection of SMS 201-995 to 52 pg/ml after injection. Serum norepinephrine levels rose from 50 pg/ml supine (normal range, 150 to 550 pg/ml) and 52 pg/ml erect before injection of SMS 201-995 to 72 pg/ml supine and 110 pg/ml erect after injection. SMS 201-995 may raise blood pressure, in part by increasing the release of circulating norepinephrine.

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There are conflicting results regarding the impact of cyclic AMP on pancreatic glucagon release. The effect of aminophylline, a phosphodiesterase inhibitor, on glucagon secretion was studied in four non-obese, non-diabetic, healthy young male volunteers. The subjects received separate infusions of: 1) aminophylline; 2) aminophylline and propranolol; 3) arginine; 4) aminophylline and arginine; 5) insulin; 6) aminophylline and insulin; and 7) aminophylline and isoproterenol. Aminophylline not only failed to alter glucagon levels but also did not affect the glucagon responses observed after arginine and insulin-induced hypoglycemia. The concurrent infusion of isoproterenol and aminophylline also failed to cause a glucagon response. Although glucagon release has been evoked by cyclic AMP in some in vitro system, administration of aminophylline to human subjects does not enhance secretion. These results indirectly suggest that cyclic AMP is of little importance in the control of glucagon secretion in man, though the effects of aminophylline at the cellular level may be complex.

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To determine if the glucoregulatory hormones, insulin and glucagon, are altered with aging inman, 44 healthy volunteers, 22-81 yr of age, were evaluted by measurement of basal levels of glucose, insulin, and glucagon in relationship to their fat mass. In addition, the secretory capacities of the alpha and beta cells were assessed by measurement of the amounts of glucagon and insulin released after intravenous administration of glucose and arginine, respectively. Although no significant differences in weight could be distinguished longitudinally, the percentage adiposity was found to increase with age. Basal concentrations of glucose, glucagon, and insulin were not appreciably altered as a function of advancing years. After intravenous glucose, the glucose disappearance rate (Kg) was significantly slower in the elderly in comparison with the young, yet no differences in glucose-induced release were found. Similarly, insulin responses after arginine infusion between young and old were indistinguishable. The release of glucagon in response to arginine infusion was not perceptibly altered during aging. Thus, despite a decline in Kg with advanging age in this healthy population, gross changes in insulin and glucagon release were not apparent. We infer from bese data that decreased carbohydrate tolerance accompanying aging in some populations may be due to factors other than abnormalities in secretion of insulin and glucagon.

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In an attempt to ascertain whether the sympathetic nervous system modulates glucagon release in man during starvation and hypoglycemia, the influence of alpha and beta adrenergic blockade on glucagon responses was studied in young, healthy men subjected to fasting and insulin-induced hypoglycemia. Six volunteers fasted for 84 h on three separate occasions. Plasma immunoreactive glucagon (IRG), measured initially at 12 h, climbed gradually from mean levels of 54 pg/ml to a zenith of 124 pg/ml at 48 h, with maintenance of these levels for the duration of the fast. The infusion of propranolol or phentolamine throughout the terminal 24 h of the second and third fasts failed to alter the pattern of IRG release. After an overnight fast, five volunteers received insulin intravenously, which evoked a mean rise in plasma IRG levels from 63 pg/ml to a maximum of 256 pg/ml at 30 min. The concurrent administration of propranolol or phentolamine did not modify the glucagon responses to insulin-induced hypoglycemia. These data suggest that the augmented glucagon release in man during starvation or after hypoglycemia is not significantly regulated by signals from the adrenergic nervous system.

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