Compliance with an intense dietary intervention and glycemic control in type 2 diabetes

Abstract

Type 2 diabetes mellitus is considered to be one of the primary causes of premature illness and death in most countries, making the projected increase in prevalence a significant public health concern. A strong association between adiposity, diet, and both insulin resistance and beta-cell dysfunction has long been recognized. A randomized, controlled dietary intervention trial was conducted to test the effects of gastric bypass surgery versus an intense dietary lifestyle intervention on T2DM status. The primary aim of the study was to evaluate the relationship between compliance to the dietary intervention and glycemic control, assessed by hemoglobin A1c, at six months after the start of the intervention. We hypothesized that a higher compliance summary score will be associated with improved glycemic control among individuals in the lifestyle arm, compared to those with lower compliance summary scores. Our secondary aim was to evaluate the relationship between each of the 5 measures of diet quality in the summary score (energy density, percentage of calories from protein, percentage of calories from added sugars, sugar-sweetened beverage intake, and fiber intake) and measures of glycemic control and of adiposity. We hypothesized that better measures of diet quality will each be associated with improved markers of glycemic control. Our study’s key findings did not support this hypothesis, as we did not find any significant associations between summary compliance score and HbA1c or other markers of glycemic control, suggesting that stricter compliance to this particular dietary intervention did not lead to lower HbA1c levels at 6 months. Our study’s secondary findings were also surprising and largely unsupportive of our hypothesis, raising interesting questions regarding our dietary intervention and future studies.