Social inequalities in new antidepressant treatment: a study at the individual and neighborhood levels.

Purpose: To determine whether social inequalities in new antidepressant treatment exist at the individual and/or neighborhood level; and their relation to access to prescribers and/or processes of care (treatment initiation and duration).

Methods: We followed 316,412 inhabitants of Marseilles (aged 18-64 years) covered by the National Health Insurance Fund for 2.5 years. We analyzed new treatments (≥1 purchase of antidepressants and none in the 6 months before the first one), and new long treatments (≥4 within 6 months after the first purchase). We tested their associations with high individual disadvantage and census block deprivation in a multivariate, multilevel logistic model adjusted for consultations with general practitioners and psychiatrists to control for access to care.

Results: High individual disadvantage was not associated with the probability of new treatments, but it was with lower odds of receiving new long treatments. Residing in deprived census blocks was associated with lower odds of receiving treatment for both dependent variables.

Conclusions: Our results suggest that social inequalities at the individual and neighborhood levels in new antidepressant treatment occur in access to specialty care and in treatment initiation and affect its duration. Further research is warranted to improve our understanding of their mechanisms.