Interscapular fat is strongly associated with insulin resistance

Abstract

Context: Subcutaneous abdominal adipose tissue (SCAAT), visceral adipose tissue (VAT), fat in the neck area [interscapular fat (IF)], and liver fat (LF) are associated with metabolic traits related to insulin resistance. Whole-body magnetic resonance imaging and spectroscopy offer a unique approach to quantify fat depots in larger cohorts. Objective: The objective was to study 1) the impact of the aforementioned fat depots on insulin sensitivity in a cross-sectional design and 2) changes in these fat depots and in insulin sensitivity during a lifestyle intervention (LI). Design: One hundred eighty-seven subjects were included in the cross-sectional study. Follow-up data during LI were available in 172 subjects. Body fat depots were quantified by whole-body magnetic resonance imaging, and representative reference slices at the umbilical level (SCAAT, VAT) and at the level of the shoulder joint (IF) were analyzed. LF was measured by 1H-magnetic resonance spectroscopy. Insulin sensitivity was estimated from an oral glucose tolerance test. Results: Cross-sectionally, SCAAT, VAT, IF, and LF were negatively associated with IS (all P < 0.0001). The changein insulin sensitivity during LI was associated with the changes in these fat depots (all P < 0.001). In a multivariate model, the change in insulin sensitivity during LI adjusted for gender, age, LF, and IF at baseline was associated with change in IF (P < 0.01) and with change in LF (P < 0.0001). Conclusions: IF represents a subcutaneous fat depot determining whole-body IS, both cross-sectionally and during LI. The impact of LF and IF on insulin sensitivity appears to be independent from each other. Additional studies areneededto clarify the metabolic properties of IF. Copyright © 2010 by The Endocrine Society.