Petri Böckerman1, Jutta Viinikainen2, Laura Pulkki-Råback3, Christian Hakulinen4, Niina Pitkänen5, Terho Lehtimäki6, Jaakko Pehkonen2, Olli T Raitakari7. 1. Turku School of Economics, Labour Institute for Economic Research, Helsinki, Finland; IZA, Bonn. Electronic address: petri.bockerman@labour.fi. 2. Jyväskylä University School of Business and Economics, Jyväskylä, Finland. 3. Helsinki Collegium for Advanced Studies, University of Helsinki, Finland; Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Finland. 4. Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Finland. 5. Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, Finland. 6. Department of Clinical Chemistry, Fimlab Laboratories and Finnish Cardiovascular Research Center Tampere, Faculty of Medicine and Life Sciences, University of Tampere, Finland. 7. Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku and Department of Clinical Physiology and Nuclear Medicine, Turku University Hospital, Turku, Finland.
Abstract
OBJECTIVES: The aim of this explorative study was to examine the effect of education on obesity using Mendelian randomization. METHODS: Participants (N=2011) were from the on-going nationally representative Young Finns Study (YFS) that began in 1980 when six cohorts (aged 30, 33, 36, 39, 42 and 45 in 2007) were recruited. The average value of BMI (kg/m2) measurements in 2007 and 2011 and genetic information were linked to comprehensive register-based information on the years of education in 2007. We first used a linear regression (Ordinary Least Squares, OLS) to estimate the relationship between education and BMI. To identify a causal relationship, we exploited Mendelian randomization and used a genetic score as an instrument for education. The genetic score was based on 74 genetic variants that genome-wide association studies (GWASs) have found to be associated with the years of education. Because the genotypes are randomly assigned at conception, the instrument causes exogenous variation in the years of education and thus enables identification of causal effects. RESULTS: The years of education in 2007 were associated with lower BMI in 2007/2011 (regression coefficient (b)=-0.22; 95% Confidence Intervals [CI]=-0.29, -0.14) according to the linear regression results. The results based on Mendelian randomization suggests that there may be a negative causal effect of education on BMI (b=-0.84; 95% CI=-1.77, 0.09). CONCLUSION: The findings indicate that education could be a protective factor against obesity in advanced countries.
OBJECTIVES: The aim of this explorative study was to examine the effect of education on obesity using Mendelian randomization. METHODS:Participants (N=2011) were from the on-going nationally representative Young Finns Study (YFS) that began in 1980 when six cohorts (aged 30, 33, 36, 39, 42 and 45 in 2007) were recruited. The average value of BMI (kg/m2) measurements in 2007 and 2011 and genetic information were linked to comprehensive register-based information on the years of education in 2007. We first used a linear regression (Ordinary Least Squares, OLS) to estimate the relationship between education and BMI. To identify a causal relationship, we exploited Mendelian randomization and used a genetic score as an instrument for education. The genetic score was based on 74 genetic variants that genome-wide association studies (GWASs) have found to be associated with the years of education. Because the genotypes are randomly assigned at conception, the instrument causes exogenous variation in the years of education and thus enables identification of causal effects. RESULTS: The years of education in 2007 were associated with lower BMI in 2007/2011 (regression coefficient (b)=-0.22; 95% Confidence Intervals [CI]=-0.29, -0.14) according to the linear regression results. The results based on Mendelian randomization suggests that there may be a negative causal effect of education on BMI (b=-0.84; 95% CI=-1.77, 0.09). CONCLUSION: The findings indicate that education could be a protective factor against obesity in advanced countries.
Authors: Alice R Carter; Dipender Gill; Neil M Davies; Amy E Taylor; Taavi Tillmann; Julien Vaucher; Robyn E Wootton; Marcus R Munafò; Gibran Hemani; Rainer Malik; Sudha Seshadri; Daniel Woo; Stephen Burgess; George Davey Smith; Michael V Holmes; Ioanna Tzoulaki; Laura D Howe; Abbas Dehghan Journal: BMJ Date: 2019-05-22
Authors: Yoonsu Cho; Philip C Haycock; Eleanor Sanderson; Tom R Gaunt; Jie Zheng; Andrew P Morris; George Davey Smith; Gibran Hemani Journal: Nat Commun Date: 2020-02-21 Impact factor: 14.919