Effects of a Mediterranean-style diet on the need for antihyperglycemic drug therapy in patients with newly diagnosed type 2 diabetes: a randomized trial.

Abstract

BACKGROUND:

Low-carbohydrate and low-fat calorie-restricted diets are recommended for weight loss in overweight and obese people with type 2 diabetes.

OBJECTIVE:

To compare the effects of a low-carbohydrate Mediterranean-style or a low-fat diet on the need for antihyperglycemic drug therapy in patients with newly diagnosed type 2 diabetes.

DESIGN:

Single-center, randomized trial. Randomization was computer-generated and unstratified. Allocation was concealed in sealed study folders held in a central, secure location until participants gave informed consent. Participants and investigators were aware of treatment assignment, and assessors of the primary outcome were blinded.

SETTING:

Teaching hospital in Naples, Italy.

PATIENTS:

215 overweight people with newly diagnosed type 2 diabetes who were never treated with antihyperglycemic drugs and had hemoglobin A(1c) (HbA(1c)) levels less than 11%.

INTERVENTION:

Mediterranean-style diet (<50% of daily calories from carbohydrates) (n = 108) or a low-fat diet (<30% of daily calories from fat) (n = 107).

MEASUREMENTS:

Start of antihyperglycemic drug therapy, defined by protocol as indicated for follow-up HbA(1c) level greater than 7% (primary outcome), and changes in weight, glycemic control, and coronary risk factors (secondary outcomes).

RESULTS:

After 4 years, 44% of patients in the Mediterranean-style diet group and 70% in the low-fat diet group required treatment (absolute difference, -26.0 percentage points [95% CI, -31.1 to -20.1 percentage points]; hazard ratio, 0.63 [CI, 0.51 to 0.86]; hazard ratio adjusted for weight change, 0.70 [CI, 0.59 to 0.90]; P < 0.001). Participants assigned to the Mediterranean-style diet lost more weight and experienced greater improvements in some glycemic control and coronary risk measures than did those assigned to the low-fat diet.

LIMITATIONS:

Investigators responsible for initiating drug therapy were not blinded to treatment assignment. Dietary intake was self-reported.

CONCLUSION:

Compared with a low-fat diet, a low-carbohydrate, Mediterranean-style diet led to more favorable changes in glycemic control and coronary risk factors and delayed the need for antihyperglycemic drug therapy in overweight patients with newly diagnosed type 2 diabetes.

PRIMARY FUNDING SOURCE:

Second University of Naples.

• Authors: Katherine Esposito, Maria Ida Maiorino, Miryam Ciotola, Carmen Di Palo, Paola Scognamiglio, Maurizio Gicchino, Michela Petrizzo, Franco Saccomanno, Flora Beneduce, Antonio Ceriello, Dario Giugliano
• Journal: Annals of internal medicine (Ann Intern Med) Vol. 151 Issue 5 Pg. 306-14 (Sep 01 2009) ISSN: 1539-3704 [Electronic] United States
• PMID: 19721018 (Publication Type: Comparative Study, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Blood Glucose
• Glycated Hemoglobin A
• Hypoglycemic Agents

Topics

• Adult
• Aged
• Blood Glucose (metabolism)
• Diabetes Mellitus, Type 2 (blood, complications, diet therapy, drug therapy)
• Diet, Carbohydrate-Restricted
• Diet, Fat-Restricted
• Diet, Mediterranean
• Exercise
• Female
• Follow-Up Studies
• Glycated Hemoglobin (metabolism)
• Humans
• Hypoglycemic Agents (therapeutic use)
• Male
• Middle Aged
• Obesity (complications, diet therapy)
• Overweight (complications, diet therapy)
• Risk Factors
• Weight Loss