5. Relationships and Social Mobility
The relationship variables available in the data were single parent, stepparent/living with partner's children, foster parents and adoptive parents; however the number of foster and adoptive parents were too small be analysed.
Relationship variables only remained in the model for two of the outcomes, with stepparents having a significantly lower risk of heart attack after adjusting for all the socio-economic, behavioural, biological, relationship and social mobility variables. Step-parents had an odds ratio of 0.05, meaning that compared to the rest of the population, stepparents had less than one-twentieth of the odds of having had a heart attack after adjusting for the other variables in the final model, namely: age, sex, residence, household tenure, marital status, smoking status, abstaining from alcohol, drinking over the recommended weekly alcohol limit, physical activity level, BMI. However only 1.1% (124) of the 11,685 participants in this model were stepparents.
The other model containing a relationship variable after adjusting for all the socio-economic, behavioural, biological, relationship and social mobility variables was for the outcome WEMWBS. Single parents had significantly higher odds of having a low WEMWBS score, indicating worse mental wellbeing, with an odds ratio of 1.52 after adjusting for the other variables in the final model, namely: age, SIMD quintile, NS-SEC, economic activity, educational qualifications, marital status, abstaining from alcohol, binge drinking, potential problem drinking, physical activity level and portions of fruit and vegetables consumed per day.
5.2 Social mobility
The social mobility variables used in the model were parental NS-SEC and a variable indicating whether the participant was upwardly or downwardly socially mobile, or socially stable. More detail is given in Section 1.3. The participant's own NS-SEC was also included in each model as a measure of socio-economic circumstances.
The variable showing whether the participant was upwardly or downwardly mobile was not a significant predictor of any of the outcomes, but parental NS-SEC was a significant predictor for COPD. The individual's own NS-SEC did not remain in the model, implying that social mobility was not important, rather that childhood socio-economic circumstances had an effect on COPD, even after adjusting for socio-economic variables from later in life (supporting the life course hypothesis 26). Participants whose parent was in an 'intermediate' job had significantly higher odds of COPD than those whose parents were in managerial and professional positions, after adjusting for the other variables which remained in the model, namely: age, sex, receiving income-related benefits, economic activity, equivalised income, smoking status and physical activity level. Parental NS-SEC also remained in the model for the outcome consuming less than two portions of fruit and vegetables per day, however this was not the model which best fit the data.