TY - JOUR
T1 - Understanding the consequences of education inequality on cardiovascular disease
T2 - Mendelian randomisation study
AU - Carter, Alice R.
AU - Gill, Dipender
AU - Davies, Neil M.
AU - Taylor, Amy E.
AU - Tillmann, Taavi
AU - Vaucher, Julien
AU - Wootton, Robyn E.
AU - Munafò, Marcus R.
AU - Hemani, Gibran
AU - Malik, Rainer
AU - Seshadri, Sudha
AU - Woo, Daniel
AU - Burgess, Stephen
AU - Davey Smith, George
AU - Holmes, Michael V.
AU - Tzoulaki, Ioanna
AU - Howe, Laura D.
AU - Dehghan, Abbas
N1 - Publisher Copyright:
© 2019 BMJ Publishing Group Limited. No commercial re-use. See rights and permissions. Published by BMJ.
PY - 2019
Y1 - 2019
N2 - Objectives To investigate the role of body mass index (BMI), systolic blood pressure, and smoking behaviour in explaining the effect of education on the risk of cardiovascular disease outcomes. Design Mendelian randomisation study. Setting UK Biobank and international genome-wide association study data. Participants Predominantly participants of European ancestry. Exposure Educational attainment, BMI, systolic blood pressure, and smoking behaviour in observational analysis, and randomly allocated genetic variants to instrument these traits in mendelian randomisation. Main outcomes measure The risk of coronary heart disease, stroke, myocardial infarction, and cardiovascular disease (all subtypes; all measured in odds ratio), and the degree to which this is mediated through BMI, systolic blood pressure, and smoking behaviour respectively. Results Each additional standard deviation of education (3.6 years) was associated with a 13% lower risk of coronary heart disease (odds ratio 0.86, 95% confidence interval 0.84 to 0.89) in observational analysis and a 37% lower risk (0.63, 0.60 to 0.67) in mendelian randomisation analysis. As a proportion of the total risk reduction, BMI was estimated to mediate 15% (95% confidence interval 13% to 17%) and 18% (14% to 23%) in the observational and mendelian randomisation estimates, respectively. Corresponding estimates were 11% (9% to 13%) and 21% (15% to 27%) for systolic blood pressure and 19% (15% to 22%) and 34% (17% to 50%) for smoking behaviour. All three risk factors combined were estimated to mediate 42% (36% to 48%) and 36% (5% to 68%) of the effect of education on coronary heart disease in observational and mendelian randomisation analyses, respectively. Similar results were obtained when investigating the risk of stroke, myocardial infarction, and cardiovascular disease. Conclusions BMI, systolic blood pressure, and smoking behaviour mediate a substantial proportion of the protective effect of education on the risk of cardiovascular outcomes and intervening on these would lead to reductions in cases of cardiovascular disease attributable to lower levels of education. However, more than half of the protective effect of education remains unexplained and requires further investigation.
AB - Objectives To investigate the role of body mass index (BMI), systolic blood pressure, and smoking behaviour in explaining the effect of education on the risk of cardiovascular disease outcomes. Design Mendelian randomisation study. Setting UK Biobank and international genome-wide association study data. Participants Predominantly participants of European ancestry. Exposure Educational attainment, BMI, systolic blood pressure, and smoking behaviour in observational analysis, and randomly allocated genetic variants to instrument these traits in mendelian randomisation. Main outcomes measure The risk of coronary heart disease, stroke, myocardial infarction, and cardiovascular disease (all subtypes; all measured in odds ratio), and the degree to which this is mediated through BMI, systolic blood pressure, and smoking behaviour respectively. Results Each additional standard deviation of education (3.6 years) was associated with a 13% lower risk of coronary heart disease (odds ratio 0.86, 95% confidence interval 0.84 to 0.89) in observational analysis and a 37% lower risk (0.63, 0.60 to 0.67) in mendelian randomisation analysis. As a proportion of the total risk reduction, BMI was estimated to mediate 15% (95% confidence interval 13% to 17%) and 18% (14% to 23%) in the observational and mendelian randomisation estimates, respectively. Corresponding estimates were 11% (9% to 13%) and 21% (15% to 27%) for systolic blood pressure and 19% (15% to 22%) and 34% (17% to 50%) for smoking behaviour. All three risk factors combined were estimated to mediate 42% (36% to 48%) and 36% (5% to 68%) of the effect of education on coronary heart disease in observational and mendelian randomisation analyses, respectively. Similar results were obtained when investigating the risk of stroke, myocardial infarction, and cardiovascular disease. Conclusions BMI, systolic blood pressure, and smoking behaviour mediate a substantial proportion of the protective effect of education on the risk of cardiovascular outcomes and intervening on these would lead to reductions in cases of cardiovascular disease attributable to lower levels of education. However, more than half of the protective effect of education remains unexplained and requires further investigation.
UR - https://www.scopus.com/pages/publications/85066035290
U2 - 10.1136/bmj.l1855
DO - 10.1136/bmj.l1855
M3 - Article
C2 - 31122926
AN - SCOPUS:85066035290
SN - 0959-8146
VL - 365
JO - BMJ
JF - BMJ
M1 - l1855
ER -