[Lifestyle and metabolic control in patients with type 2 diabetes mellitus. Construct validation of IMEVID questionnaire]

Abstract

Objective: To evaluate construct validity of an instrument to measure lifestyle in patients with type 2 diabetes mellitus (IMEVID questionnaire)

Design: Comparative cross-sectional study.

Setting: Six family medicine units (primary care).

Patients: 412 adults with type 2 diabetes.

Measurements: The IMEVID was applied by self-administration and the following metabolic control parameters values were measured: body mass index (BMI), waist/hip index (WHI), hemoglobin A1C (HbA1C), total cholesterol (TC), triglycerides (TG), systolic blood pressure (SBP), diastolic blood pressure (DBP), and the average of fasting plasma glucose in the last three months (FG). The test hypothetic construct was that higher total scores in the IMEVID (better lifestyle) would be associated with lower values in the metabolic control parameters. Three groups of subjects were formed based on the total score: group one (<quartile 25), group two (among quartile 25 and 75) and group three (>quartile 75). Differences on these parameters between groups were researched.

Results: 389 subjects completed the study, 69,2% were women. Seven IMEVID domains had weak correlations at least with two of eight parameters (r between 0.22 and 0.16; P<.05). The total score had correlation with six of eight parameter (r between 0.18 and 0.10; P< or =.05). The group three subjects had lower levels of BMI, WHI, HbA1C, FG, TC and TGL than group one subjects (P<.05).

Conclusions: IMEVID has construct validity to measure the lifestyle in subjects with DM2. Its total score discriminates outstanding clinical characteristics in these patients.