Prevalence of depression and association to socioeconomic position. Results from the Lolland-Falster Health Study

Purpose
To describe the prevalence of self-reported depression in a socioeconomically deprived area in Denmark and the association to socioeconomic position (SEP) defined by education, occupation, and being in financial strain.

Method
13,955 adults completing the Major Depression Inventory (MDI) in the Lolland-Falster Health Study questionnaire were included.

Multivariate logistic regression on symptoms of depression based on MDI sum score and ICD-10 scores, associated to education, occupation, and financial strain – unadjusted and adjusted for sex and age group.

Results
We found a prevalence of depression at 2.7% using the ICD-10 category, at 7.6% using the MDI sum score, and a very strong association between symptoms of depression and SEP.

The adjusted odd ratios (aORs) for depression for each socioeconomic group compared to the opposite showed that having no postsecondary education was associated with an aOR of 2.9; being temporarily out of job with an aOR of 7, and being in financial strain with an aOR of 8. Using more strict criteria for depression (ICD-10), showed an aOR of 4 when having no education, an aOR of 8 when temporarily out of job, and an aOR of 10 for positive depression when in financial strain.

Conclusion
Symptoms of depression are strongly associated to SEP. Estimations of the prevalence of depressive disorders in population studies should take this into account. We estimate a more accurate prevalence of depressive disorders to be at 7.6% in this socioeconomically deprived area of Denmark.