An epigenetic score for BMI based on DNA methylation correlates with poor physical health and major disease in the Lothian Birth Cohort

Hamilton, O. K.L. et al. (2019) An epigenetic score for BMI based on DNA methylation correlates with poor physical health and major disease in the Lothian Birth Cohort. International Journal of Obesity, 43(9), pp. 1795-1802. (doi: 10.1038/s41366-018-0262-3) (PMID:30842548) (PMCID:PMC6760607)

Abstract

Background: The relationship between obesity and adverse health is well established, but little is known about the contribution of DNA methylation to obesity-related health outcomes. This study tests associations between an epigenetic score for body mass index (BMI) and health-related, cognitive, psychosocial and lifestyle outcomes in the Lothian Birth Cohort 1936. This study also tests whether these associations are independent of phenotypic BMI. Method: Analyses were conducted using data from the Lothian Birth Cohort 1936 (n = 892). Weights for the epigenetic BMI score were derived using penalised regression on methylation data from unrelated Generation Scotland participants (n = 2562). Associations were tested for replication in an independent sample: the Lothian Birth Cohort 1921 (n = 433). Results: A higher epigenetic BMI score was associated with higher BMI (R2 = 0.1), greater body weight (R2 = 0.06), greater time taken to walk 6 m, poorer lung function and poorer general physical health (all R2 = 0.02), greater levels of triglycerides (R2 = 0.09), greater %total HbA1c (R2 = 0.06), lower levels of high-density lipoprotein cholesterol (HDL; R2 = 0.08), higher HDL ratio (HDL/total cholesterol; R2 = 0.03), lower health-related quality of life, physical inactivity, and greater social deprivation (all R2 = 0.02). The epigenetic BMI score (per SD) was also associated with type 2 diabetes (OR 2.17, 95% CI 1.67, 2.84), cardiovascular disease (OR 1.45, 95% CI 1.24, 1.71) and high blood pressure (OR 1.30, 95% CI 1.13, 1.49; all p < 0.00026 after Bonferroni correction). Associations were replicated for BMI (R2 = 0.06), body weight (R2 = 0.04), health-related quality of life (R2 = 0.02), HbA1c (R2 = 0.07) and triglycerides (R2 = 0.07; all p < 0.0045 after Bonferroni correction). Conclusions: We observed and replicated associations between an epigenetic score for BMI and variables related to poor physical health and metabolic syndrome. Regression models with both epigenetic and phenotypic BMI scores as predictors accounted for a greater proportion of variance in all outcome variables than either predictor alone, demonstrating independent and additive effects of epigenetic and phenotypic BMI scores.

• Item Type: Articles
• Additional Information: The LBC1936 is supported by Age UK (Disconnected Mind programme) and the Medical Research Council [MR/M01311/1]. The LBC1921 is supported by the Biotechnology and Biological Sciences Research Council [SR176], the Chief Scientist Office [CZB/4/505; ETM/55] and the Medical Research Council [R42550]. Methylation typing was supported by the Centre for Cognitive Ageing and Cognitive Epidemiology (Pilot Fund award), Age UK, The Wellcome Trust Institutional Strategic Support Fund, The University of Edinburgh, and The University of Queensland. This work was conducted in the Centre for Cognitive Ageing and Cognitive Epidemiology, which is supported by the Medical Research Council and Biotechnology and Biological Sciences Research Council [MR/K026992/1], and which supports Ian Deary. Generation Scotland received core support from the Chief Scientist Office of the Scottish Government Health Directorates [CZD/16/6] and the Scottish Funding Council [HR03006]. Genotyping of the GS:SFHS samples was carried out by the Genetics Core Laboratory at the Wellcome Trust Clinical Research Facility, Edinburgh, Scotland, and was funded by the Medical Research Council UK and the Wellcome Trust (Wellcome Trust Strategic Award “STratifying Resilience and Depression Longitudinally” [(STRADL) 104036/Z/14/Z]).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Hamilton, Dr Olivia
• Authors: Hamilton, O. K.L., Zhang, Q., McRae, A. F., Walker, R. M., Morris, S. W., Redmond, P., Campbell, A., Murray, A. D., Porteous, D. J., Evans, K. L., McIntosh, A. M., Deary, I. J., and Marioni, R. E.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > MRC/CSO SPHSU
• Journal Name: International Journal of Obesity
• Publisher: Springer Nature
• ISSN: 0307-0565
• ISSN (Online): 1476-5497
• Published Online: 06 March 2019
• Copyright Holders: Copyright © 2019 The Authors
• First Published: First published in International Journal of Obesity 43(9): 1795-1902
• Publisher Policy: Reproduced under a Creative Commons License