7424 Measurements of Key Regulators of Energy Intake in Young and Midlife Women with Overweight or Obesity

Abstract Disclosure: E. Tama: None. R. Rivera: None. S. Fansa: None. D. Anazco: None. W. Ghusn: None. S. Faubion: None. A. Acosta: Consulting Fee; Self; Amgen Inc. Grant Recipient; Self; Vivus USA, Novo Nordisk. C. Shufelt: None. M.D. Hurtado: None. Introduction: Midlife women (ages 40 to 65) experience age-related weight gain (0.4-0.7 kg/year) due to physiologic and psychosocial changes. Evidence supports that age-related decrease in lean mass and its subsequent effect on energy expenditure are key physiologic factors. To date, the are no data describing if changes in the main regulators of energy intake (i.e., hunger, satiation, and satiety) across women’s lifespan play a role in weight gain during midlife. The aim of this study is to characterize measurements of satiation, satiety, and appetite sensations through early adulthood and midlife in women with obesity. Methods: This is a cross sectional study of women aged 19-65 with overweight or obesity who have undergone measurements of (i) body composition by DXA scan; (ii) resting energy expenditure (REE) by indirect calorimetry; (iii) satiation by calories consumed to satiation (CTS) during an ad libitum meal test; (iv) satiety by time needed to empty 50% of the stomach content (GEt1/2) in a gastric emptying study and plasma satiety hormone levels (PYY, GLP-1, and CCK); and (v) appetite sensations by visual analog scales (VAS) for hunger and fullness. We present data as mean ± standard deviation. We performed simple correlations between these variables and age. We performed multiple regression analyses to adjust for body composition and REE. Results: Our cohort included 552 mostly white (93%) women, with a mean age of 41±11 years and a mean BMI of 37±7 kg/m2. Increased age significantly correlated with higher waist circumference (r=0.1, p=0.006), waist/hip ratio (r=0.1, p=0.01), and total fat mass % (r=0.1, p=0.04); and with lower lean mass % (r=-0.1, p=0.04) and REE (r=-0.3, p<0.0001). Increased age was associated with decreased hunger sensation (i.e., lower preprandial VAShunger after an overnight fast, r=-0.1, p=0.04; and lower postprandial VAShunger 4hr after a standardized 320-kcal breakfast, r=-0.1, p=0.001), stronger satiation (i.e., lower CTS, r=-0.1, p=0.001), and more prolonged satiety (i.e., higher GEt1/2, r=0.1, p=0.02; higher postprandial GLP-1 levels, r=0.1, p=0.03; and higher postprandial VASfullness after and ad libitum meal, p=0.1, p=0.008). After adjusting for lean mass % and REE, the correlations between age and hunger sensations and satiation measurement, but not satiety measurements, were maintained. Conclusion: Our results show that older women have lower lean mass % and REE. After adjusting for these variables, older women experience decreased hunger sensation and achieve satiation with a lower number of calories. As these changes in theory would protect against midlife weight gain, the differences in body composition and REE remain the most likely culprit. Further research is necessary to investigate if there are other key factors that may contribute to weight gain such as the hedonic or emotional components of food intake. Presentation: 6/2/2024