Effects of increased body mass index on employment status: a Mendelian randomisation study

Abstract

Background The obesity epidemic may have substantial implications for the global workforce, including causal effects on employment, but clear evidence is lacking. Obesity may prevent people from being in paid work through poor health or through social discrimination. We studied genetic variants robustly associated with body mass index (BMI) to investigate its causal effects on employment. Dataset/methods White UK ethnicity participants of working age (men 40–64 years, women 40–59 years), with suitable genetic data were selected in the UK Biobank study (N = 230,791). Employment status was categorised in two ways: first, contrasting being in paid employment with any other status; and second, contrasting being in paid employment with sickness/disability, unemployment, early retirement and caring for home/family. Socioeconomic indicators also investigated were hours worked, household income, educational attainment and Townsend deprivation index (TDI). We conducted observational and two-sample Mendelian randomisation (MR) analyses to investigate the effect of increased BMI on employment-related outcomes. Results Regressions showed BMI associated with all the employment-related outcomes investigated. MR analyses provided evidence for higher BMI causing increased risk of sickness/disability (OR 1.08, 95% CI 1.04, 1.11, per 1 Kg/m2 BMI increase) and decreased caring for home/family (OR 0.96, 95% CI 0.93, 0.99), higher TDI (Beta 0.038, 95% CI 0.018, 0.059), and lower household income (OR 0.98, 95% CI 0.96, 0.99). In contrast, MR provided evidence for no causal effect of BMI on unemployment, early retirement, non-employment, hours worked or educational attainment. There was little evidence for causal effects differing by sex or age. Robustness tests yielded consistent results. Discussion BMI appears to exert a causal effect on employment status, largely by affecting an individual’s health rather than through increased unemployment arising from social discrimination. The obesity epidemic may be contributing to increased worklessness and therefore could impose a substantial societal burden.

Obesity- attributable costs of absenteeism among working adults in Portugal

“…Some authors, when applying a longitudinal methodology to understand the causal relationship between obesity and absenteeism, found that obesity could act both as a direct explanatory variable and as a mediator for other variables linked to loss of productivity, as obesity is also considered a risk factor for several chronic diseases [ 22 , 23 ]. BMI also, appears to exert a causal effect on employment status, largely by affecting an individual’s health rather than through increased unemployment arising from social discrimination [ 24 ]. These results are consistent with our findings showing similar degrees of obesity-associated effects on absenteeism, both when it is evaluated separately and when associated with other risk factors, such as chronic diseases and lifestyle habits.…”

The association of obesity-related traits on COVID-19 severity and hospitalization is affected by socio-economic status: a multivariable Mendelian randomization study

“… 55–60 There is also evidence that obesity-related traits can affect SES via multiple factors that have been previously grouped into three categories: 61 (i) health effects: high BMI increases the risk of several chronic diseases, which could affect work ability and subsequently income; 61 , 62 (ii) reduced job performance: body shape affects health capital, presenteeism, self-esteem and employment status, which impact income; 63 , 64 (iii) discrimination from employers. 65 , 66 Accordingly, there are likely multiple pathways by which income could affect the association between obesity-related traits and COVID-19 outcomes. Although our MVMR analysis clearly shows that the effect of obesity-related traits on COVID-19 outcomes is not independent of the income effect, the bidirectional relationship between anthropometric traits and income does not permit us to make a hypothesis regarding the temporal relationship between the exposures investigated.…”

Effects of depression on employment and social outcomes: a Mendelian randomisation study

“…The outcomes used were previously described in our paper relating body mass index to employment outcomes 12. All outcomes were obtained at the baseline interview.…”

“…The ‘in paid employment’ and ‘not in paid employment’ sum to less than 100% due to some participants giving invalid answers for the employment question. The numbers in this table are the same as in our previous body mass index employment study 12NA, not applicable.…”