Pioglitazone treatment in type 2 diabetes mellitus when combined with portion control diet modifies the metabolic syndrome.
BACKGROUND
Treatment with thiazolidinediones (TZDs) produces weight gain.


OBJECTIVE
To test whether a portion control diet could prevent weight gain during treatment with pioglitazone in patients with type 2 diabetes mellitus (T2DM).


METHODS
This 16-week randomized, open-label, parallel arm study compared three groups: (i) pioglitazone plus the American Diabetes Association diet (Pio + ADA); (ii) pioglitazone plus a portion control weight loss diet (Pio + PC); (iii) metformin plus the American Diabetes Association diet (Met + ADA). All participants received the same advice about calorie reduction, lifestyle change and exercise.


METHODS
Fifty-one men and women with T2DM, naive to TZDs, were randomized to a 16-week study. Pioglitazone (Pio) was titrated to a dose of 45 mg/day and metformin (Met) to a dose of 2 g/day. Fasting blood was collected for lipids, insulin and glycosylated haemoglobin A1c (HbA1c) at baseline and 16 weeks.


RESULTS
Forty-eight of fifty-one randomized subjects completed the study. Patients treated with Pio + ADA gained 2.15 +/- 1.09 kg (mean +/- SD) compared with a weight loss of 2.59 +/- 1.25 kg (p < 0.05) in the Pio + PC group, and a weight loss of 3.21 +/- 0.7 kg (p < 0.05) in the Met + ADA group. Waist circumference and visceral adipose tissue decreased significantly more in the Pio + PC group than in the Pio + ADA group. High-density lipoprotein cholesterol levels were significantly increased in the Pio + PC group compared with the Met + ADA group. Pioglitazone reduced insulin resistance (homeostasis model assessment of insulin resistance (HOMA-IR)) more than metformin. No significant differences between groups were seen for glucose, insulin, HbA1c or low-density lipoprotein cholesterol levels.


CONCLUSIONS
Pio + PC, prevented weight gain, reduced waist circumference and visceral fat compared with Pio + ADA diet.
Gupta
A K
AK
Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA. alok.gupta@pbrc.edu
Smith
S R
SR
Greenway
F L
FL
Bray
G A
GA
D000328:Adult; D000368:Aged; D000886:Anthropometry / Q000379:methods; D003131:Combined Modality Therapy; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy / Q000188:drug therapy* / Q000503:physiopathology; D004038:Diet, Reducing; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D024821:Metabolic Syndrome / Q000139:chemically induced / Q000503:physiopathology / Q000517:prevention & control*; D008687:Metformin / Q000627:therapeutic use; D008875:Middle Aged; D000077205:Pioglitazone; D045162:Thiazolidinediones / Q000009:adverse effects / Q000627:therapeutic use*; D055105:Waist Circumference / Q000187:drug effects; D015430:Weight Gain / Q000187:drug effects
D007004:Hypoglycemic Agents; D045162:Thiazolidinediones; D008687:Metformin; D000077205:Pioglitazone