The impact on utilities of differences in body weight among Canadian patients with type 2 diabetes

OBJECTIVE

The objective of this study was to estimate utility values for hypothetical health states that describe differences in weight and quality of life associated with type 2 diabetes mellitus (DM) from Canadians with type 2 DM. The impact on utility values was examined separately for participants with a body mass index (BMI) of 18 to less than 25 kg/m(2) ('healthy'), 25 to less than 30 ('overweight'), and 30 or more ('obese').

METHODS

The health state descriptions were modified from a published diabetes utility study. Health states included a base-case type 2 DM health state (at participants' current weight), and six health states where the weight and attendant quality of life impact varied (base case ±3%, ±5%, and ±7% weight). Utilities were elicited using the time trade-off technique. Linear regression modeling was used to estimate the utility increment or decrement associated with a one unit difference in BMI.

RESULTS

Among 96 participants, the mean age was 55 years and 51% were men. The mean BMI was 32 kg/m(2) and 84% wanted to lose weight. The mean (SD) utility for the base-case state was 0.911 (0.013). Mean utilities (utility decrements) were 0.907 (-0.004), 0.865 (-0.046) and 0.806 (-0.105) for the health states describing an increased weight of 3%, 5% and 7%, respectively; and 0.923 (+0.012), 0.940 (+0.029) and 0.949 (+0.038) for the health states describing a decreased weight of 3%, 5% and 7%, respectively. For every increase of 1 kg/m(2) BMI there was an associated decrease in utility of 0.0472 (95% CI: 0.0375, 0.0569) and for every decrease of 1 kg/m(2) BMI there was an associated increase in utility of 0.0171 (95% CI: 0.0103, 0.0238).

CONCLUSIONS

The preferences of Canadian patients with type 2 DM for diabetes-related health states varied according to the weight, and quality of life impact, associated with that health state. Increased weight had a greater effect on utilities than decreased weight.

Differences in diabetic co-morbidity between Aboriginal and non-Aboriginal people living in Bella Coola, Canada

INTRODUCTION

OBJECTIVES

(1) To identify which medical disorders are significantly associated with being a diabetic in the setting of an isolated, rural community; and (2) to determine if there are differences between Aboriginal and non-Aboriginal diabetics.

METHODS

DESIGN

population based retrospective chart review.

STUDY POPULATION

people living in the Bella Coola Valley, Canada, and having a chart at the Bella Coola Medical Clinic as at September 2001.

MAIN OUTCOME MEASURES

known diabetes related co-morbidity (retinopathy, nephropathy, coronary artery disease, peripheral vascular disease, neuropathy).

RESULTS

There were 126 adult (>18 years old) diabetics living in the Bella Coola Valley. Prevalence rates for history of alcohol issues, retinopathy, coronary artery disease, cerebrovascular disease, peripheral vascular disease, peripheral neuropathy, hypertension, hypercholesterolemia, and nephropathy were 44%, 14%, 19%, 8%, 7%, 10%, 54%, 47%, and 7% respectively. For the 1597 non-diabetics living in the Bella Coola Valley, respective prevalence rates for these same co-morbidities were 20%, 0.3%, 2%, 1.5%, 1%, 1%, 10%, 6%, and 0.6%. The study did not demonstrate that Aboriginal people living in the Bella Coola Valley have an increased prevalence of diabetes associated co-morbidities over and above that found in the non-Aboriginal diabetic population. This was despite the fact the smoking rate was higher in the Aboriginal population.

CONCLUSIONS

The development of diabetes in both Aboriginal and non-Aboriginal people living in the Bella Coola Valley was clearly associated with the presence of multiple co-morbidities, including hypertension, hypercholesterolemia, coronary artery disease, cerebrovascular disease, and neuropathy. Rates of diabetes associated co-morbidities were similar for both Aboriginal and non-Aboriginal diabetic populations. The authors speculate that a diet rich in fish oils (omega-3 fatty acids) accounted for the lower than expected rates of cardiovascular disease among this Aboriginal population.

Alterations in non-insulin-mediated glucose uptake in the elderly patient with diabetes

It is increasingly recognized that alterations in non-insulin-mediated glucose uptake (NIMGU) play an important pathogenic role in disorders of carbohydrate metabolism. This study was conducted to determine whether NIMGU is impaired in elderly patients with type 2 diabetes. Healthy elderly control subjects (n = 19, age 76 +/- 1 years, BMI 26.8 +/- 1.1 kg/m2) and elderly patients with type 2 diabetes (n = 19, age 76 +/- 2 years, BMI 27.5 +/- 0.9 kg/m2) underwent a 240-min glucose clamp study. Octreotide was infused to suppress endogenous insulin release, and tritiated glucose methodology was used to measure glucose uptake and disposal rates. For the first 180 min, glucose was kept at fasting levels. From 180 to 240 min, glucose was increased to 11 mmol/l. At fasting glucose levels, glucose uptake was similar in both groups. However, glucose clearance was reduced in patients with diabetes (control 1.68 +/- 0.05 ml x kg(-1) x min(-1); diabetes 1.34 +/- 0.07 ml x kg(-1) x min(-1), P < 0.0001). During hyperglycemia, glucose uptake was reduced in patients with diabetes (control 3.16 +/- 0.09 mg x kg(-1) x min(-1); diabetes 2.57 +/- 0.11 mg x kg(-1) x min(-1), P < 0.0001). Peripheral glucose effectiveness (SG) was less in patients with diabetes (control 1.28 +/- 0.04 ml x kg(-1) x min(-1); diabetes 0.94 +/- 0.08 ml x kg(-1) x min(-1), P < 0.0001). Hepatic glucose output and hepatic SG were not different between groups. We conclude that the effect of glucose on glucose uptake is impaired in elderly patients with type 2 diabetes, a finding that may have therapeutic implications for this patient population.

Counterregulatory hormone responses after long-term continuous subcutaneous insulin infusion with lispro insulin

OBJECTIVE

To determine whether the long-term use of insulin lispro (LP) affects the counterregulatory hormone response to hypoglycemia.

RESEARCH DESIGN AND METHODS

Ten patients (age range 26-51 years; ratio of men to women 9:1; BMI 24.9 +/- 0.48; mean HbA1c 7.84 +/- 0.25%) with IDDM, treated with continuous subcutaneous insulin infusion (CSII; Disetronic H-TRON V100) were studied using a double-blind, crossover design. Patients were randomized to LP or human regular insulin (HR) for 3 months and then crossed over to the other insulin for an additional 3 months. All meal boluses were given 0-5 min before breakfast, lunch, and dinner. Counterregulatory hormone responses to a stepped hypoglycemic clamp (consecutive glucose levels in mmol/l: 4.2; 3.5; 2.8, each for 1 h) were evaluated at the end of each treatment period.

RESULTS

HbA1c was significantly lower with LP versus HR (7.47 +/- 0.28% vs. 7.9 +/- 0.26%, P = 0.04). The incidence of hypoglycemia per 30 days (capillary blood glucose < 3.0 mmol/l and/or symptoms) during the last month of the study was significantly lower with LP versus HR (8.7 +/- 2.9 vs. 11.8 +/- 2.9, P = 0.03). The total daily insulin dosage was not different in the two treatment periods. There was no episode of severe hypoglycemia or diabetic ketoacidosis. The peak growth hormone, cortisol, glucagon, and epinephrine responses during the same period of hypoglycemia were not different for each treatment period.

CONCLUSIONS

The use of LP in CSII results in improved glycemic control and a decrease in the frequency of hypoglycemia without adversely affecting counterregulatory hormone response to hypoglycemia.

Insulin lispro in CSII: results of a double-blind crossover study

Insulin lispro is a human insulin analog that dissociates more rapidly than human regular insulin after subcutaneous injection, resulting in higher insulin levels at an earlier point in time and a shorter duration of action. The aim of the study was to evaluate if this pharmacokinetic difference would translate into better postprandial and overall control in 30 IDDM patients (age, 35.1 +/- 1.5 years; male-female ratio, 17:13; BMI, 24.8 +/- 0.5 kg/m2; HbA1c, 8.03 +/- 0.13% at baseline) treated with continuous subcutaneous insulin infusion (CSII; Disetronic H-TRON V100) in a double-blind crossover clinical study. Patients were randomized to insulin lispro or human regular insulin for 3 months before crossing over to the other insulin for another 3 months. All meal boluses were given immediately before breakfast, lunch, and supper. An eight-point blood glucose profile was measured once weekly, and HbA1c levels were measured monthly. At the end of the 3-month treatment period, HbA1c levels were significantly lower with insulin lispro, compared with human regular insulin: 7.66 +/- 0.13 vs. 8.00 +/- 0.16% (P = 0.0041). While preprandial, bedtime, and 2:00 A.M. values for blood glucose were not significantly different, 1-h postprandial blood glucose was significantly improved after breakfast, lunch, and dinner with insulin lispro, compared with human regular insulin: 8.35 vs. 9.79 mmol/l (P = 0.006), 7.58 vs. 8.74 mmol/l (P = 0.049), and 7.85 vs. 9.01 mmol/l (P = 0.03). The incidence of hypoglycemia per 30 days (blood glucose levels, <3.0 mmol/l) was 8.4 +/- 1.3 before randomization, decreasing to 6.0 +/- 0.9 for insulin lispro and to 7.6 +/- 1.3 for regular insulin during the last month of the study. Two patients in each group reported insulin precipitation. We conclude that insulin lispro improves glycemic control in CSII without increasing the risk of hypoglycemia.

NIDDM in the elderly

OBJECTIVE

We conducted this study to assess the metabolic alterations in elderly patients with NIDDM.

RESEARCH DESIGN AND METHODS

Healthy, lean (n = 15; age, 73 +/- 1 years; BMI, 23.8 +/- 0.5 kg/m2), and obese (n = 10; age, 71 +/- 1 years; BMI, 28.9 +/- 1.2 kg/m2) control subjects and lean (n = 10; age, 75 +/- 2 years; BMI, 24.0 +/- 0.5 kg/m2) and obese (n = 23; age, 73 +/- 1 years; BMI, 29.9 +/- 0.7 kg/m2) NIDDM patients underwent a 3-h glucose tolerance test, a 2-h hyperglycemic glucose clamp study, and a 3-h euglycemic glucose clamp study with tritiated glucose methodology to measure glucose production and disposal rates.

RESULTS

Waist-to-hip ratio (WHR) was greater in both lean and obese NIDDM patients than in control subjects. Insulin responses during the oral glucose tolerance test were similar in obese subjects (control subjects: 417 +/- 64 pmol/l; NIDDM patients: 392 +/- 47 pmol/l) but were reduced in lean NIDDM patients (control subjects: 374 +/- 34 pmol/l; NIDDM patients: 217 +/- 20 pmol/l, P < 0.01). Lean and obese NIDDM patients had absent first-phase insulin responses during the hyperglycemic clamp. Second-phase insulin responses were reduced in lean (P < 0.01 vs. control subjects by analysis of variance) but not obese NIDDM patients. Hepatic glucose output was not increased in lean or obese NIDDM patients. Steady-state (150-180 min) glucose disposal rates were 16% less in lean NIDDM patients (control subjects: 8.93 +/- 0.37 mg.kg LBM (lean body mass)-1.min-1; NIDDM patients: 7.50 +/- 0.28 mg.kg LBM-1.min-1, P < 0.05) and 37% less in obese NIDDM patients (control subjects: 8.17 +/- 0.38 mg.kg LBM-1.min-1; NIDDM patients: 5.03 +/- 0.36 mg.kg LBM-1.min-1, P < 0.001).

CONCLUSIONS

Lean elderly NIDDM patients have a profound impairment in glucose-induced insulin release but mild resistance to insulin-mediated glucose disposal. Obese elderly NIDDM patients have adequate circulating insulin, but marked resistance to insulin-mediated glucose disposal. Hepatic glucose output is not increased in elderly NIDDM patients.