Dietary glycaemic index and glycaemic load in a rural elderly population (60-74 years of age) and their relationship with cardiovascular risk factors.

Purpose: To examine the association between dietary glycaemic index (GI) and dietary glycaemic load (GL) with cardiovascular disease (CVD) risk factors in a rural elderly population.

Methods: A cross-sectional study was conducted in 343 subjects (60-74 years) residing in a Spanish rural area (Priego de Córdoba). Subjects were selected using stratified random sampling. Food intake was assessed using a validated food frequency questionnaire (FFQ). We assigned GI values to each item of the FFQ to estimate dietary GI and GL. Multivariate linear regression models were fitted to assess the association between GI/GL with CVD risk factors (blood glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, apolipoprotein A1, body mass index, waist circumference and blood pressure). The potential modifying effect of sex, smoking status, diabetes and medication has been explored.

Results: A statistically significant inverse association between dietary GI and blood glucose was found in the multivariate model (p = 0.029): for every 10 unit increment of GI, serum glucose levels decreased by 0.2 units. However, statistical significance was lost after controlling for diabetes or hypoglycaemic medication. In the crude model, dietary GL was associated with triglycerides (ß for every 10 GL units increase = 0.70, p = 0.005), but statistical significance was lost in the multivariate model (p = 0.508). No associations were found between dietary GI/GL and the rest of the variables studied.

Conclusions: Neither dietary GI nor GL were associated with CVD risk factors in the study population of Priego de Córdoba. Results obtained suggest the necessity to consider the diagnosis of diabetes in these studies.