Search

OBJECTIVE—To investigate a possible association of BMI with retinopathy and neuropathy in type 1 diabetes. Retinopathy and neuropathy may not only be related to glycemic control and diabetes duration but also to blood pressure and BMI. RESEARCH DESIGN AND METHODS—A total of 592 type 1 diabetic patients without nephropathy were studied (M/F: 324/268; age: 41 ± 12 years; duration: 19 ± 11 years; HbA1c [A1C]: 7.9 ± 1.1%). Patients were subdivided according to BMI: 168 men and 146 women with BMI RESULTS—Hypertension (>130/85 mmHg) was present in 40%, retinopathy in 53%, and neuropathy in 43% of patients. Overweight subjects had more retinopathy (63 vs. 45%, P < 0.0001, odds ratio [OR] = 2.1) and neuropathy (49 vs. 38%, P = 0.008, OR = 1.6) than normal-weight patients. Patients with retinopathy were older (45 ± 12 vs. 37 ± 11 years, P < 0.0001) and had a longer diabetes duration (25 ± 10 vs. 12 ± 8 years, P < 0.0001), a higher A1C (8.0 ± 1.1 vs. 7.7 ± 1.1%, P = 0.001), and a higher BMI (25.8 ± 4.1 vs. 24.7 ± 4.2 kg/m2, P = 0.001) than individuals without retinopathy. The same results are found in neuropathy. Logistic regression analysis showed that diabetes duration (β = 0.15, P < 0.0001), blood pressure (β = 0.22, P = 0.0047), and A1C (β = 0.24, P = 0.01), but not BMI, lipid levels, sex, or age, were independent risk factors for retinopathy. Likewise, duration (β = 0.05, P < 0.0001), age (β = 0.04, P = 0.0001), A1C (β = 0.35, P < 0.0001), and sex (β = 0.74, P = 0.0001) but not BMI, lipid levels, or hypertension were independently associated with neuropathy. Men had more neuropathy than women (50 vs. 34%, P < 0.0001, OR = 1.9). Leptin and adiponectin levels did not differ between individuals with or without microvascular complications. CONCLUSIONS—Retinopathy and neuropathy are more prevalent in overweight (BMI ≥25 kg/m2) type 1 diabetic subjects. However, logistic regression analysis showed that diabetes duration and A1C remain the main determinants for retinopathy and neuropathy.

OBJECTIVE—Delayed gastric emptying and/or gastrointestinal symptoms occur in 30–50% of diabetic patients. Known contributing factors are autonomic neuropathy and acute hyperglycemia, but the role of gastric autoimmunity has never been investigated, although 15–20% of type 1 diabetic patients exhibit parietal cell antibodies (PCAs). We studied gastric motility in diabetes in relation to PCA status, autonomic nerve function, HbA1c, thyroid-stimulating hormone (TSH), Helicobacter pylori (HP), acid production, and gastric histology. RESEARCH DESIGN AND METHODS—Gastric emptying of solids and liquids (measured by 13C-octanoic acid and 13C-glycine breath tests, respectively) was tested in euglycemic conditions in 42 type 1 diabetic patients (male/female: 29/13; 15 PCA+; mean age 40 ± 15 years; mean HbA1c 7.8 ± 0.9%). Gastrointestinal symptoms, autonomic nerve function (Ewing tests), PCA status (indirect immunofluorescence), gastric histology, and acid secretion (pentagastrin) were assessed. RESULTS—Solid gastric emptying was delayed in 40% and liquid emptying in 36% of patients. Gastric motility did not correlate with symptoms. PCA status, gastric morphology, and acid secretion were similar in those with and without gastroparesis. HbA1c level (β = 1.34, P = 0.011) was the only risk factor for delayed solid emptying in a logistic regression model testing HbA1c, autonomic nerve function, PCA, HP status, age, sex, diabetes duration, and TSH. Half-emptying time for liquids correlated with TSH level (r = 0.83, P < 0.0001) and autonomic neuropathy score (r = −0.79, P = 0.001). CONCLUSIONS—We found that ∼50% of type 1 diabetic patients studied had delayed gastric emptying that did not correlate with symptoms. Gastric autoimmunity did not contribute to diabetic gastroparesis. Metabolic control was worse in patients with delayed solid emptying.

There exists much evidence suggesting a major role for the oxidized low density lipoprotein (LDL) and VLDL particles in the pathogenesis of atherosclerosis. Although obesity is characterized by dyslipidemia, less is known about the oxidation capacity of lipoproteins in obese subjects. We measured the oxidizability in vitro in 21 premenopausal women with a BMI of 36.7+/-5.4 and compared them to 18 age-matched controls (BMI 21.9+/-1.8). The oxidizability of the non-HDL fraction is evaluated by measuring the fluorescence and thiobarbituric acid reactive substances (TBARS; MDA nM/mg non-HDL) at different time intervals of incubation. TBARS formation increased linearly with the increase of lipids both in non-obese and obese subjects. TBARS, measured every 30 min, increased in non-obese controls up to a maximum of 59.6 at 180' in contrast to a maximum of 77.1 at 180' (P < 0.001) in obese, but healthy, normocholesterolemic subjects. At each measurement the TBARS were significantly higher (P < 0.01-0.001) in obese subjects. Also the lag-time (period from zero to the start of the particle oxidation process) was significantly lower (92.5 vs. 123.4; P < 0.001) in obese subjects, when compared to lean controls. BMI correlates significantly with TBARS formation and its log transformed values (maximum P < 0.001). The lag-time was negatively related (n=39 total group, r=- 0.57, P < 0.001) to body weight and BMI. A significant relationship exists between TBARS formation (up to r=0.59) and triglyceride levels and a negative relationship exists with HDL-cholesterol levels. In vitro oxidizability of non-HDL lipoproteins is significantly increased in obese, non-diabetic subjects and related to increased body weight and triglyceride levels. Further studies are necessary to explore the underlying mechanisms for this phenomenon.