Educational inequality in multimorbidity: causality and causal pathways. A mendelian randomisation study in UK Biobank

BMC Public Health

Research

Chris Salisbury¹  Rupert A Payne²  Laura D Howe³  Tom G Richardson³  Teri-Louise North³  Deborah C Bishop³  Alice R Carter³  Sean Harrison³  Robyn E Wootton⁴ 

[1] Centre for Academic Primary Care, Population Health Sciences, University of Bristol, Bristol, UK;Centre for Academic Primary Care, Population Health Sciences, University of Bristol, Bristol, UK;Exeter Collaboration for Academic Primary Care, Department of Health and Community Sciences, University of Exeter, Exeter, UK;MRC Integrative Epidemiology Unit, Population Health Sciences, University of Bristol, Bristol, UK;MRC Integrative Epidemiology Unit, Population Health Sciences, University of Bristol, Bristol, UK;Nic Waals Institute, Lovisenberg Diaconal Hospital, Oslo, Norway;School of Psychological Science, University of Bristol, Bristol, UK;

关键词: Multimorbidity;    Determinants;    Inequality;    Education;    Mendelian randomization;    Causality;   

DOI  :  10.1186/s12889-023-16369-1

 received in 2023-02-24, accepted in 2023-07-24,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundMultimorbidity, typically defined as having two or more long-term health conditions, is associated with reduced wellbeing and life expectancy. Understanding the determinants of multimorbidity, including whether they are causal, may help with the design and prioritisation of prevention interventions. This study seeks to assess the causality of education, BMI, smoking and alcohol as determinants of multimorbidity, and the degree to which BMI, smoking and alcohol mediate differences in multimorbidity by level of education.MethodsParticipants were 181,214 females and 155,677 males, mean ages 56.7 and 57.1 years respectively, from UK Biobank. We used a Mendelian randomization design; an approach that uses genetic variants as instrumental variables to interrogate causality.ResultsThe prevalence of multimorbidity was 55.1%. Mendelian randomization suggests that lower education, higher BMI and higher levels of smoking causally increase the risk of multimorbidity. For example, one standard deviation (equivalent to 5.1 years) increase in genetically-predicted years of education decreases the risk of multimorbidity by 9.0% (95% CI: 6.5 to 11.4%). A 5 kg/m2 increase in genetically-predicted BMI increases the risk of multimorbidity by 9.2% (95% CI: 8.1 to 10.3%) and a one SD higher lifetime smoking index increases the risk of multimorbidity by 6.8% (95% CI: 3.3 to 10.4%). Evidence for a causal effect of genetically-predicted alcohol consumption on multimorbidity was less strong; an increase of 5 units of alcohol per week increases the risk of multimorbidity by 1.3% (95% CI: 0.2 to 2.5%). The proportions of the association between education and multimorbidity explained by BMI and smoking are 20.4% and 17.6% respectively. Collectively, BMI and smoking account for 31.8% of the educational inequality in multimorbidity.ConclusionsEducation, BMI, smoking and alcohol consumption are intervenable causal risk factors for multimorbidity. Furthermore, BMI and lifetime smoking make a considerable contribution to the generation of educational inequalities in multimorbidity. Public health interventions that improve population-wide levels of these risk factors are likely to reduce multimorbidity and inequalities in its occurrence.

【 授权许可】

CC BY   
© BioMed Central Ltd., part of Springer Nature 2023

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