Background Half the world’s population now live in cities and by 2030 this proportion will increase to two-thirds. There is growing concern over the negative implications for health associated with living in urban areas. Individuals living in cities are thought to be at an increased risk of cancer, heart attack, stroke and schizophrenia and cities are also associated with increased deprivation and disadvantage. Studies testing the association between urban dwelling and disorders such as depression and anxiety have produced conflicting results. This study aims to discover if living in a city increases your risk of suffering from depression or anxiety, using antidepressant and anxiolytic prescribing as proxy indicators.

Methods Anxiolytic and antidepressant prescribing data from the national prescribing database was linked to individual level census data from the Northern Ireland longitudinal study. Multilevel regression analyses were carried out to test the association between city dwelling and prescription drug uptake, adjusting for natural clustering of individuals within neighbourhoods. The effect of selective migration was tested by identifying moves to and from city and rural areas.

Results In the unadjusted model individuals living in cities were 80% more likely than those living in rural areas to receive an anxiolytic (OR 1.80 [95% CI 1.64, 1.96]) 37% more likely to receive an antidepressant (1.37 [1.29, 1.45]). After full adjustment for age, gender, marital status, education, measures of socio-economic disadvantage, limiting long term illness, area deprivation and crime levels individuals living in cities were still 34% more likely to receive anxiolytic medication compared to those living in rural areas (1.34 [1.23, 1.46]). The association between city dwelling and antidepressant uptake attenuated more. Results from the selective migration analysis found that “ever living” in a city increased the likelihood of receiving anxiolytic medication but had no significant effect on antidepressant uptake.

Conclusion Even after adjustment for known mental health risk factors city living increases the likelihood of receiving anxiolytic medication. Some studies have suggested that the lack of social networks and individualistic society created in cities has a negative impact on mental health. Interestingly though city dwelling appears to impact anxiety disorders more than depression. Further analyses will be carried out adjusting for social fragmentation.