The association between material living standard and psychological distress: Results from a New Zealand population survey

Abstract

People with a low material living standard experience more psychological distress than those with a high living standard, but previous studies suggest the size of this difference is modest. To measure the association between living standard and psychological distress using a multidimensional measure of living standard, the Economic Living Standard Index (ELSI). Adults aged 25-64 years (n = 8,465) were selected from a New Zealand community survey. Logistic regression models were used to compare household income and ELSI scores as risk factors for high psychological distress, defined as a K10 score of 12 or over. In the population, the prevalence of high psychological distress was 5.8%. The prevalence of high distress increased steeply with decreasing living standard. In the most deprived decile according to ELSI score, 24.3% had high distress, compared to 0.8% in the least deprived decile. For household income, high distress was present in 15.9% of people in the lowest decile and 2.2% of the highest decile. In fully adjusted models, ELSI score remained significantly associated with high distress but household income was not. The mental health disparity between those at opposite ends of the social spectrum is very large. Comprehensive measures such as the ELSI give a more accurate estimate of this disparity than household income.