Income inequality and Neisseria gonorrhoeae notifications in females: a country-level analysis.

Background: Patterns of population susceptibility to sexually transmissible infections may be influenced by various social determinants of health, however these receive relatively little attention. Income inequality is one such determinant that has been linked to a number of poor health outcomes. The objective of this analysis was to determine whether there is an association between income inequality and Neisseria gonorrhoeae notification rates when measured at the country level. Methods: Gini coefficients, gonorrhoea notification rates among women, per capita gross domestic product and approximate size of female population were obtained for 11 countries of the OECD. Linear regression was used to measure the association between income inequality and gonorrhoea notification rates, using generalised estimation equations (GEE) to control for the non-independence of repeat measures from particular countries. Results: A total of 36 observations from 11 countries were included. Gini coefficients ranged from 0.21 to 0.38 and gonorrhoea notifications from 0.7 to 153 per 100 000 females. Significant associations were found between country-level income inequality and gonorrhoea notification rates among women (b = 17.79 (95% CI: 10.64, 24.94, P < 0.01). Conclusions: Significant associations were found, highlighting the importance of acknowledging and accounting for social determinants of sexual health and suggesting that further research in this arena may be fruitful.