The association between neuropeptide levels, lifestyle and BMI in postpartum women – a follow-up study

Abstract

Abstract “The association between neuropeptide levels, lifestyle and BMI in postpartum women – a follow-up study” Author: Ameli Ingemansson. Supervisor: Ulrika Andersson Hall. Co-supervisor: Agneta Holmäng Degree project, Programme in Medicine Department of physiology. University of Gothenburg, Sweden, 2016. Background: Women with a pre-pregnancy BMI >25 kg/m² both have a higher risk of pregnancy-related complications such as gestational diabetes, as well as of remaining overweight post-partum, which is a well-known risk factor for many welfare-diseases. Among other factors, lifestyle changes and neuropeptide levels may influence BMI development during pregnancy and post-partum. Aim: To follow up women 3 – 5 year post-partum and to measure their levels of neuropeptides (leptin, insulin and Agouti-related peptide (AgRP)) in cerebrospinal fluid (CSF) and serum (s), and to study if BMI changes (pre- and post-partum) and fat mass (post-partum) were related to neuropeptide levels and insulin sensitivity. Lifestyle characteristics such as diet and physical activity were also studied. Methods: Women (n=25) were recruited from a previous pregnancy study conducted in 2010 – 2013. Blood and CSF samples were collected at caesarean and post-partum, body composition were determined, and questionnaires regarding dietary intake, physical activity was distributed. The women were divided into three groups based on their BMI changes from pre-pregnancy to follow-up visits: Loss, Stable and Gain. Results: The lowest BMI was found in the Stable group (BMI 26.2 ± 4.5 kg/m2 at follow up), where also s-AgRP levels remained higher post-partum compared with the other groups. The BMI Gain group (BMI 31.7 ± 3.1 kg/m2 at follow up) had the lowest CSF/S leptin quota, highest increase in CSF insulin levels and were also found to have the highest insulin resistance at follow up (HOMA-IR = 2.4 ± 0.8). Additionally, BMI correlated to changes in s-AgRP levels post-partum (ρ = -0.511) and to CSF/S leptin (ρ = -0.672). Regarding lifestyle, fat intake correlated (ρ = 0.576) to the increment of CSF AgRP after pregnancy, and physical activity correlated (ρ = -0.507) to lower fat mass. Conclusions: High s-AgRP levels and a high CSF/S leptin quota, in addition to physical activity might predict lower BMI after pregnancy. Evidence of correlation between fat intake and CSF AgRP levels was found for the first time and would be of interest to study further.