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P D Home

Publications and source records attributed to P D Home.

At least 37 records · Page 2Linked to original sources
PubMed1999

Rapid-acting insulin secretagogues: a clinical need?

The history of achieving adequate insulin secretion in Type 2 diabetes has interesting parallels with Type 1 diabetes. Initial insulin secretagogue therapy involved short-acting sulphonylureas--tolbutamide being introduced 40 years ago--and early insulin therapy used unmodified (soluble) insulin. Subsequently, long-acting sulphonylureas and insulin were introduced, but more recently short-acting agents have become popular again. This approach was endorsed by the European non-insulin-dependent diabetes mellitus guidelines of 1989/1993. The trend at present is to match modern rapid-acting agents (such as repaglinide or the rapid-acting insulin analogues) to physiological meal-time insulin requirements in both types of diabetes. The fundamental reasons for tailoring therapy to meal-times fall into two categories: a pathophysiological rationale and a behavioural rationale. The pathophysiological rationale for tailoring treatment to mealtimes is based on the importance of restoring the mealtime insulin secretion profiles of patients with Type 2 diabetes to physiological levels to re-establish the tight control of blood glucose levels seen in healthy individuals. The behavioural rationale is derived from the observation that most people with Type 2 diabetes are overweight and would like to reduce calorie consumption, but that the risk of hypoglycaemia does not allow them to be flexible over their day-to-day calorie intake. These observations suggest that the matching of a meal-time pharmacodynamic profile to a patient's eating habits would provide a knowledge-based rationale for achieving good blood glucose control once dietary means alone are inadequate. Evidently, this can be usefully combined with other pharmacological approaches (insulin sensitizers or basal insulin). The need for combination therapy is increasingly likely as the defect in insulin secretion progresses.

Blood Glucose↗
PubMed1998

The effect of the insulin analog lispro on nighttime blood glucose control in type 1 diabetic patients.

OBJECTIVE: Unmodified regular insulin has a long absorption tail, unlike the fast-acting insulin analog lispro, and may contribute to hypoglycemia in the early part of the night. A randomized crossover double-blind study was performed to compare blood glucose concentrations in the early part of the night in type 1 diabetic patients receiving lispro or unmodified regular human insulin, in random order, on 2 separate study days. RESEARCH DESIGN AND METHODS: We studied 23 C-peptide-negative patients; 12 were using a premeal plus basal insulin regimen, and 11 were using twice-daily insulin injections. Patients were admitted to the investigation unit at 5:00 P.M. and received a single dose of lispro or unmodified regular human insulin before the evening meal. In both groups, the NPH insulin dose remained unchanged. Identical meals and snacks were eaten at the same time during both study days. RESULTS: Average postprandial (6:00-10:00 P.M.) blood glucose concentrations were significantly lower after lispro therapy compared with human insulin (7.1 +/- 0.4 [SE] vs. 8.5 +/- 0.4 mmol/l, P = 0.0002). Nighttime (midnight to 4:00 A.M.) blood glucose concentrations were significantly higher after lispro compared with human insulin (10.3 +/- 0.4 vs. 9.1 +/- 0.4 mmol/l, P = 0.02). This difference was greatest in patients on the premeal plus basal insulin regimen (11.6 +/- 0.5 vs. 8.7 +/- 0.4 mmol/l, P < 0.001). The incidence of nocturnal hypoglycemia (midnight to 4:00 A.M., blood glucose < 3.5 mmol/l) was less with lispro compared with unmodified insulin (1 vs. 6 patients, P = 0.04). Nighttime (midnight to 4:00 A.M.) 3-hydroxybutyrate (102 +/- 13 vs. 51 +/- 7 mumol/l, P = 0.000) and glycerol (52 +/- 3 vs. 42 +/- 2 mumol/l, P < 0.01) were significantly higher after lispro therapy compared with human insulin in patients on the premeal plus bolus insulin regimen. CONCLUSIONS: Lispro can improve postprandial blood glucose control and reduce the incidence of nocturnal hypoglycemia at the expense of nocturnal hyperglycemia and hyperketonemia in patients using a premeal plus basal insulin regimen.

Adult↗
PubMed1998

Optimal provision of daytime NPH insulin in patients using the insulin analog lispro.

OBJECTIVE: Insulin lispro improves early postprandial blood glucose control but can result in late interprandial hyperglycemia. As an approach to resolving this problem, we performed a randomized, crossover study with four treatment arms, comparing the daytime metabolic profile after either premeal lispro alone or premeal lispro with optimal daytime NPH insulin and with standard human regular insulin. RESEARCH DESIGN AND METHODS: Twelve C-peptide negative type 1 diabetic patients were studied on four separate study days, at least 7 days apart. On each study day, patients received one of the four study insulin treatments, in random order, with identical meals and snacks. The four treatments were 1) premeal human regular insulin before lunch and supper at unchanged dose; 2) premeal lispro (unchanged dose) at lunchtime and dinner; 3) pre-lunch reduced-dose lispro (70%) before lunch and supper with supplemental lunchtime NPH and with a 6-h interval until dinner; and 4) pre-lunch reduced-dose lispro (70%) before lunch and supper with supplemental lunchtime NPH and with a 8-h interval until dinner. All patients were using their usual premeal plus basal insulin regimen during the period of the study, with human regular insulin before meals and NPH insulin at bedtime. RESULTS: Postprandial blood glucose concentrations (1230-1500) were lower after reduced or usual lispro dose compared with human regular insulin (5.5+/-0.2 and 5.6+/-0.2 vs. 8.2+/-0.5 mmol/l, P < 0.001), with no difference between the lispro doses. However, prepran-Dial (1800) blood glucose levels deteriorated to higher levels after usual-dose lispro alone compared with either human regular insulin (P < 0.05) or reduced-dose lispro plus NPH (P < 0.05) (8.9+/-0.3 vs. 7.1+/-0.8 and 6.4+/-0.4 mmol/l), with no difference between human regular insulin and reduced-dose lispro plus NPH. During the 2 h between the usual and delayed mealtime, blood glucose concentrations remained controlled on lispro plus NPH (2000: 6.5+/-0.4 mmol/l). CONCLUSIONS: Reduced-dose lunchtime lispro plus NPH maintained the improvement in postprandial blood glucose control with no deterioration in interprandial blood glucose control, even up to a late meal.

Adult↗
PubMed1998

Improved glycemic control with insulin aspart: a multicenter randomized double-blind crossover trial in type 1 diabetic patients. UK Insulin Aspart Study Group.

OBJECTIVE: To compare glycemic control obtained with the new rapid-acting insulin analog insulin aspart with that obtained with unmodified human insulin using algorithm-driven dosage adjustment. RESEARCH DESIGN AND METHODS: This was a multicenter randomized double-blind crossover study of 90 male subjects with type 1 diabetes. Insulin aspart or soluble human insulin was administered before meals, and NPH insulin was administered at bedtime as basal therapy. Each 4-week study period ended with a 24-h inpatient serum insulin and plasma glucose profile. RESULTS: The 24-h plasma glucose control obtained with insulin aspart, as assessed by excursions of blood glucose outside a predefined normal range (4.0-7.0 mmo/l), was superior (22% reduction in excursion, P < 0.01). Fructosamine levels remained unchanged with insulin aspart, with daytime glycemic control superior but nighttime glycemic control inferior. Eight-point home blood glucose profiles confirmed that insulin aspart significantly improved postprandial blood glucose control after lunch and dinner (P < 0.05) without deterioration of preprandial blood glucose control. Hypoglycemic episodes requiring third-party intervention were significantly fewer with insulin aspart than with human insulin (20 vs. 44 events, P < 0.002). Insulin aspart was well tolerated. CONCLUSIONS: In comparison with human insulin, insulin aspart can improve postprandial glycemic control as assessed by a reduction in hyper- and hypoglycemic excursions in people with type 1 diabetes. For its full potential to be realized, it will need to provide better control of nighttime hyperglycemia.

Adult↗
PubMed1998

Optimization of evening insulin dose in patients using the short-acting insulin analog lispro.

OBJECTIVE: A three-way, crossover, open-label, randomized study was designed to compare the evening and night (1800-0800) glycemic control when the evening premeal lispro dose was reduced by 20% and the bedtime basal NPH dose increased by 25%, or when the basal NPH dose was moved to before dinner at 1800, compared with the control arm on standard premeal human regular insulin and pre-bedtime NPH insulin. RESEARCH DESIGN AND METHODS: A total of 13 type 1 diabetic patients who use a premeal plus basal insulin regimen were studied on three separate days, with identical meals and snacks at the same times on each study day. On the control study day, patients received human regular insulin before dinner and NPH at bedtime in their usual doses. On another day, lispro was given before dinner with a dose reduction of 20%, and NPH at bedtime at 125% of usual dose. In the third regimen, the lispro and NPH were administered together in their usual dose before the evening meal by separate injections. The three regimens were tested in random order. RESULTS: Postprandial (1800-2200) blood glucose concentrations were lower after reduced-dose lispro compared with human regular insulin (6.0 +/- 0.3 [SEM] vs. 7.4 +/- 0.3 mmol/l, P < 0.05). Nighttime (2400-0400) blood glucose concentrations were not different (8.6 +/- 0.3 vs. 9.2 +/- 0.3 mmol/l, NS), and prebreakfast concentrations were also unchanged (7.7 +/- 0.9 vs. 8.7 +/- 0.8 mmol/l) after lispro with increased-dose NPH compared with standard insulin. By contrast, both nighttime (10.0 +/- 0.3 mmol/l, P < 0.05) and fasting glucose concentrations (10.8 +/- 0.6 mmol/l, P < 0.05) were significantly higher with dinnertime usual-dose lispro plus dinnertime usual-dose NPH compared with standard human insulin. Hypoglycemia at night (blood glucose < 3.0 mmol/l) did not differ between study days, but it was more frequent postprandially after dinner usual-dose lispro plus early NPH (2 vs. 7 patients, P = 0.062). CONCLUSIONS: With lower mealtime and higher basal bedtime insulin doses, patients using insulin lispro may be able to gain an overall improvement in evening blood glucose control without deteriorated nighttime glucose levels. Earlier basal NPH dosage alone does not ameliorate the nighttime hyperglycemia of short-acting insulin analog regimens.

3-Hydroxybutyric Acid↗
PubMed1997

The effect of portal and peripheral insulin delivery on carbohydrate and lipid metabolism in a miniature pig model of human IDDM.

A pig model of insulin-dependent diabetes was used to examine the importance of the portal-systemic insulin gradient for whole-body metabolic control. Six pigs had jugular vein, portal vein, and carotid artery cannulae implanted before being made diabetic (150 mg kg[-1] streptozotocin). Each animal received 4 weeks of portal and 4 weeks of peripheral insulin delivery in random order. The blood glucose target range was 5-10 mmol x l(-1), and serum fructosamine and fasting and postprandial blood glucose concentrations were not different between peripheral and portal insulin infusion. Insulin requirement was not different between the 4 week infusion periods, but fasting peripheral insulin levels after peripheral delivery (124 +/- 16 (mean +/- SEM) pmol x l[-1]) were significantly higher (p < 0.05) than in portally infused (73.8 +/- 5.4 pmol x l[-1]) or pre-diabetic control animals (68.4 +/- 3.6 pmol x l[-1]). Basal hepatic glucose output was also higher (p < 0.05) in peripherally (4.2 +/- 0.4 mg x kg[-1] x min[-1]) than in portally infused animals (2.9 +/- 0.4 mg x kg[-1] x min[-1]) or controls (3.0 +/- 0.3 mg x kg[-1] x min[-1]). Clamp glucose metabolic clearance rate was, however, not different between the peripheral and portal insulin delivery routes (8.1 +/- 1.0 vs 9.0 +/- 0.7 ml x kg[-1] x min[-1]), although both were significantly lower (p < 0.05) than that measured in prediabetic control animals (11.7 +/- 1.0 ml x kg[-1] x min[-1]). Lipid profiles and subfractions were similar in all three groups. It is concluded that the portal route of delivery is superior to the peripheral in maintaining more appropriate insulin concentrations and control of hepatic glucose output, although in the absence of euglycaemia it is still associated with significant metabolic abnormalities.

Animals↗
PubMed1997

Intensive insulin therapy in clinical practice.

Achieving optimal blood glucose control, without an unacceptable rate of hypoglycaemia or unacceptable restrictions on lifestyle, is not simple with presently available insulin preparations and monitoring tools. There is considerable evidence that achieved control is relatively independent of the means or frequency of insulin delivery provided at least two injections per day are used, probably due to a combination of the unphysiological nature of insulin absorption profiles, the poor reproducibility of insulin absorption in any individual, and the erratic nature of normal human behavior. Accordingly the appropriate use of insulin to obtain good metabolic control requires the continued and informed expertise of both patient and advising professional, but also attention from both to self-motivation in order to make the desired lifestyle changes possible. Newer approaches to insulin delivery will continue to demand a high level of understanding and expertise to make them effective, until such time as automatic minute-to-minute control of insulin delivery can be restored.

Diabetes Mellitus↗
PubMed1996

Archaeoparasitology at a 17th century colonial site in Newfoundland.

Excavations at the 17th century site of Ferryland during the past 2 summers have revealed thousands of artifacts and the remains of several structures. Of particular interest here was the discovery of the remains of a privy and associated stable. Examination of privy contents revealed the presence of eggs of 4 parasites: Ascaris, Trichuris, Taenia, and Dicrocoelium. Their identification represents the first reported discovery of parasite remains in an archeological context in Canada. Due to possible contamination by domestic animal feces, it was not possible to determine with certainty if the eggs are of human origin.

Animals↗
PubMed1995

The contribution of proinsulin and des-31,32 proinsulin to the hyperinsulinemia of diabetic and nondiabetic cirrhotic patients.

We used specific, monoclonal antibody-based, two-site immunoradiometric assays to test the hypothesis that serum levels of proinsulin and des-31,32 proinsulin would be increased in cirrhosis, particularly in those with overt diabetes. A 75-g oral glucose tolerance test was performed after an overnight fast in eight cirrhotic patients with diabetes (fasting blood glucose, 7.8 +/- 2.2 [SE] mmol/L), seven nondiabetic cirrhotic patients, and eight normal control subjects. Fasting serum immunoreactive insulin levels were approximately six times higher in cirrhotics than in controls, but were not different between diabetic and nondiabetic cirrhotic patients. After oral glucose, the incremental area under the serum insulin concentration curve was 3,475 +/- 1,009 pmol.L-1.h in nondiabetic cirrhotic patients, significantly higher than in controls (761 +/- 48, P < .001) or diabetic cirrhotic patients (881 +/- 186, P < .05). Fasting serum proinsulin levels in diabetic cirrhotic patients (24.0 +/- 5.7 pmol/L) were higher than in controls (2.3 +/- .05, P < .001) or nondiabetic cirrhotic patients (4.4 +/- 0.8, P < .005). Fasting serum levels of des-31,32 proinsulin were also much higher in diabetic cirrhotic patients than in nondiabetic cirrhotic patients or controls (P < .02 and P < .005, respectively). Fasting proinsulin plus des-31,32 proinsulin constituted 12.5% +/- 1.4% of serum immunoreactive insulin in diabetic cirrhotics, higher than in nondiabetic cirrhotics (3.7% +/- 0.5%, P < .001) and normal controls (7.8% +/- 1.5%, P = .035).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Pharmacoeconomics of diabetes surveillance and detection programmes.

Primary prevention of insulin-dependent diabetes mellitus (IDDM, type I diabetes) remains a research goal. Primary prevention of non-insulin-dependent diabetes mellitus (NIDDM, type II diabetes) is likely to remain part of general health education on healthy lifestyles. However, the often delayed diagnosis of type II diabetes, accompanied by early development of complications, offers opportunities for detection programmes, provided that these can overcome the hurdle of the low annual incidence of this disease. By contrast, programmes for the detection of arterial risk factors and treatable complications of previously diagnosed diabetes are well established as an integrated, and thus efficient, annual review. The results of such review guide the different forms of management programmes such as educational programmes for foot care and smoking, drug therapy for hypertension, dyslipidaemia and early nephropathy, and crisis management (laser photocoagulation) of proliferative retinopathy. Such annual review, additional to review of lifestyle and metabolic control, offers opportunities for on-going preventive education and is now the basis of quality development and needs assessment technologies.

Diabetes Mellitus, Type 2↗
PubMed1993

Forearm muscle metabolism in primary hypothyroidism.

Thyrotoxicosis is associated with increased skeletal muscle glucose metabolism and lipid oxidation in the fasted state. Conversely, in hypothyroidism, glucose metabolism is reduced. The present study has assessed in patients the effects of chronic thyroid hormone deficiency, on insulin-stimulated skeletal muscle metabolism, using a combination of the forearm and hyperinsulinaemic euglycaemic clamp techniques. Seven female patients presenting with primary auto-immune hypothyroidism were studied at presentation and 4-9 months after being rendered biochemically euthyroid. No significant differences were demonstrated between the hypothyroid and euthyroid states in forearm muscle blood flow, or in glucose or lipid metabolism.

Adult↗