N. Wilson Rodger

Pedometer-determined ambulatory activity in individuals with type 2 diabetes

This cross-sectional study presents the first normative data on pedometer-determined ambulatory activity, defined as steps/day, in 160 (98 males, 62 females; age=52.4 +/- 5.3 years; BMI=32.3 +/- 5.7) free-living individuals with type 2 diabetes. Participants took 6662 +/- 3077 steps per day, less than that reported in nondiabetic samples and more than that reported for samples living with more restrictive chronic conditions including claudication, joint replacement, chronic obstructive lung disease, and chronic heart failure. Steps/day and BMI were inversely and significantly correlated (r=-0.27, P<0.01). Further, there was a significant difference between BMI categories (from normal weight to obesity class III) with regard to steps/day (F=2.96, P<0.05). The difference was most apparent between the highest obesity classes (II and III) and normal weight categories. This data is useful for sample comparison purposes. In addition the standard deviation or variance estimates can be used to calculate samples sizes for intervention efforts. Objective quantification of ambulatory activity via simple and inexpensive pedometers permits researchers and practitioners to easily screen for level of activity along a continuum. This study opens the door for future research and clinical applications including identifying threshold values related to important health outcomes and evaluating incremental change due to various interventions in this population.

Preliminary outcome evaluation of the First Step Program: a daily physical activity intervention for individuals with type 2 diabetes

The First Step Program uses simple and inexpensive pedometers to incrementally increase walking behaviors in sedentary individuals with type 2 diabetes. The pilot sample consisted of nine individuals (six women, three men; group mean age 53+/-6; group mean body mass index=32.9+/-3.4kg/m(2)). A timed self-paced walk while wearing the pedometer allowed for the conversion of changes in pedometer steps per day to time in minutes per day. There was an immediate and dramatic increase in walking behavior (an average of 34.3min of walking a day) that was sustained even 2 months post-intervention and after withdrawal of contact (an average of 22.6min of walking a day). Improvements in other outcomes (systolic blood pressure and waist girth) support a valid change in behavior. Although preliminary, these results warrant further investigation of such approaches.

Development of a theory-based daily activity intervention for individuals with type 2 diabetes.

PURPOSE This article describes a theory-driven approach to developing a physical activity intervention for sedentary individuals with type 2 diabetes. METHODS Development of the intervention was based on 6 essential elements of program theory: problem definition, critical inputs, mediating processes, expected outcomes, extraneous factors, and implementation issues. Each element was formulated based on available literature and in collaboration with both intended service deliverers (diabetes educators) and recipients (sedentary persons with type 2 diabetes). RESULTS Diabetes education requires a simple physical activity intervention template that is feasible, acceptable, and effective in a variety of settings. Successful programs are individualized, specific, flexible, and based on walking. Pedometers have potential as self-monitoring and feedback tools. The primary expected outcome is an increase in physical activity, specifically walking. Behavior modification and social support are critical to adoption and adherence. CONCLUSIONS Theory-driven interventions specify what works for whom and under what conditions of delivery. The underlying theoryguides the evaluation, refinement, and clinical replication of an intervention. Recruitment, delivery, and follow-up are realworld implementation issues.

Self-Awareness in Diabetes: Using Body Cues, Circumstances, and Strategies

PURPOSE This research was the first phase of a study designed to develop and pilot test an educational program to increase self-awareness of salient body cues in adults with Type 1 diabetes. The purpose of this study was to identify (1) the cues, sensations, and circumstances that people with diabetes and their families associate with hypoglycemia, euglycemia, and hyperglycemia; and (2) the types of strategies that people with diabetes use to tune in to body cues and sensations. METHODS A series of four focus group sessions were held at monthly intervals with four female participants and four family members. These sessions were audiotaped and transcribed verbatim. RESULTS Participants described the existence of unique as well as usual body cues for hyperglycemia and hypoglycemia and the circumstances associated with these cues. Subjective and objective strategies were identified for tuning into these body cues and sensations. CONCLUSIONS People with diabetes should be encouraged to identify their own body cues that signify different levels of glycemia because these personal cues may be different than classical textbook symptoms. Even people with hypoglycemia unawareness may recognize unique cues that replace the autonomic ones they have lost.

Miglitol, an α-glucosidase inhibitor, prevents the metformin-induced fall in serum folate and vitamin B12 in subjects with type 2 diabetes

Abstract Since folate and vitamin B 12 absorption may be increased by colonic bacterial activity, their status may be improved by miglitol, an α-glucosidase inhibitor of potential use in the treatment of diabetes. To test this, subjects with type 2 diabetes were treated for 9 months in a double-blind, randomized controlled fashion with either placebo (n=45), miglitol (n=45), metformin (n=62), or a combination of miglitol and metformin (n=47). Glycated hemoglobin (HbA 1c ), serum and red cell folate and serum vitamin B 12 were measured and 3-day dietary records obtained before and after therapy. Compared to placebo, all 3 active treatments significantly reduced HbA 1c , metformin to a greater extent than miglitol and the combination to a greater extent than metformin. Dietary folate intake did not change on any treatment. Serum folate and vitamin B 12 , respectively, did not change on placebo, but fell by 14% and 15% on metformin and rose by 12% and 23% on miglitol. The changes in folate and vitamin B 12 concentrations on metformin were significantly different from those on miglitol. On combination therapy, both folate and vitamin B 12 tended to rise, but the difference from metformin was only significant for folate. These data support the hypothesis that increased carbohydrate delivery to the colon increases intestinal biosynthesis of folate. The combination of miglitol with metformin may prevent the metformin-induced fall in serum folate and vitamin B 12 .

Relationship between habitual diet and blood glucose and lipids in non-insulin dependent diabetes (NIDDM)

Abstract The relationships (adjusted for age, sex, diabetes duration and BMI) between habitual diet and blood glucose and lipids in NIDDM subjects from 7 cities in Canada were studied using duplicate 3-day diet records and measurements of fasting plasma glucose (FPG), glycosylated haemoglobin (HbAlc), serum total (TC) and HDL cholesterol and triglycerides (TG). In subjects treated by diet alone (n=75), HbAlc was inversely related to carbohydrate intake (r= −0.302, p=0.01) and directly to diet glycaemic index (r=0.321, p

Effects of Changing the Amount and Source of Dietary Carbohydrates on Symptoms and Dietary Satisfaction Over a 1-Year Period in Subjects with Type 2 Diabetes: Canadian Trial of Carbohydrates in Diabetes (CCD)

OBJECTIVES To determine the long-term effects of changing the amount or source of dietary carbohydrate on quality of life (QOL), symptoms and dietary satisfaction in people with type 2 diabetes. METHODS Subjects with diabetes treated by diet alone (n=162) were randomly assigned to high-carbohydrate/high-glycemic-index (HGI) diets; high-carbohydrate/low-glycemic-index (LGI) diets; or lower-carbohydrate/high-monounsaturated-fat (LC) diets for 1 year. We measured QOL at baseline and at studys end, and we measured symptoms and dietary satisfaction quarterly. RESULTS The HGI, LGI and LC diets contained, respectively, 47±1, 52±1 and 40±1% energy carbohydrate; 30±1, 27±1 and 40±1% fat with GI 64±0.4, 55±0.4 and 59±0.4. Significantly more participants reported increased flatulence on LGI than on LC and HGI diets at 3 months (41%, 19%, 14%; p<0.05), but not at 12 months (29%, 17%, 17%; ns). Abdominal distension was more severe (46% vs. 14%, 19%; p<0.05), and headache less severe (8% vs. 22%, 23%; p<0.05) on LGI than on both other diets. Increased appetite was more severe on LC (33%) than on HGI diets (14%, p<0.05). Joint/limb pains were less severe on LGI (16%) than HGI (28%) diets. LC elicited more severe gloomy thoughts (23%) than LGI (4%; p<0.05) but greater dietary-satisfaction (70%; p<0.05) than LGI (40%) and HGI (48%) diets. For all diets, glycated hemoglobin (A1C) levels increased less in those who gained less weight, had less increased appetite and were more satisfied with the enjoyment obtained from eating. CONCLUSIONS Each diet elicited increased severity of 1 or more symptoms than the other diets. Although overall dietary satisfaction was greater on the 40% carbohydrate diet than on the 50% carbohydrate diet, the LGI diet was no less satisfying than the HGI diet. Changes in appetite and dietary satisfaction may influence body weight and glycemic control, or vice-versa.

Colocalization of pancreatic polypeptide and insulin in secretory granules of a pancreatic endocrine neoplasm

A 45-year-old woman presented with clinical symptoms of hypoglycemia of 4 months duration. Laboratory testing confirmed hyperinsulinemia; mild hypercalcemia and hypergastrine-mia were also documented. At the time of operation, 3 pancreatic endocrine neoplasms were found, and a diagnosis of multiple endocrine neoplasia type I was made. Immunohistochem-istry and immunoelectron microscopy showed all the tumors to be plurihormonal, each containing three or more of the following: insulin, glucagon, somatostatin, pancreatic polypep-tide, gastrin, and serotonin. Electron microscopy of 2 tumors revealed numerous atypical granules. In 1 tumor, pancreatic polypeptide and insulin were colocalized in secretory granules by dual-staining immunoelectron microscopy. To our knowledge, this combination of hormones has not been described previously in pancreatic endocrine neoplasms and suggests that such neoplasms, like mature pancreatic endocrine cells, may originate from pluripotential common precursor cells.