Figure 4.

Adjusted correlations in Native Americans of at least half Southwestern heritage. Association analysis of 2-AG and AEA with residuals of (a, b) SLEEP, as well as OEA with residuals of (c) 24-hour RQ, (d) 24-hour lipid oxidation, and (e) carbohydrate oxidation in Native Americans of at least half Southwestern heritage. SLEEP was adjusted for age, sex, FM, and FFM. Twenty-four-hour RQ was adjusted for age, sex, energy balance, and body fat. Twenty-four-hour lipid and carbohydrate oxidation were adjusted for age, sex, energy balance, FM, and FFM (25). Endocannabinoids and OEA concentrations were log₁₀-transformed to reduce the influence of extreme values on the multivariate model. Sensitivity analyses for significant results were performed: in (a), removing the individual with the highest residual SLEEP from analysis did not change the significance of reported results (dFβ = −2.05, r = −0.38, P = 0.04). The same sensitivity analyses were performed for (b): upon removal of the individual with the lowest AEA concentration, the association of skeletal muscle AEA concentration with residual SLEEP was still significant (dFβ = −3.71, r = −0.46, P = 0.01). This was also true for the other outlier with a slightly higher AEA concentration (dFβ = 1.59, r = −0.63, P = 0.0003). Excluding both outliers from association analysis did not affect the significance of presented results (r = −0.43, P = 0.02). Pearson correlation (r) reported. Due to incomplete EE and/or lipid assessment in skeletal muscle and adipose tissue, the number of individuals included here in the presented analyses differed from the overall group of 35 Native Americans of at least half Southwestern heritage. Compared with the latter, these participants were not different regarding age, sex, FM, FFM, body mass index, percentage body fat, glucose regulation, and AEA, 2-AG, and OEA tissue and plasma concentrations (all P > 0.05).