Previous population-based studies have partially provided inconsistent results regarding the co-variates of chronic depression, which were likely to be attributable to methodological limitations. The present paper that compared people with chronic major depressive disorder (MDD), non-chronic MDD and no mood disorder in the community focused on specific atypical and melancholic depression symptoms and subtypes of MDD, family history (FH) of mood disorders, measured physical cardio-vascular risk factors (CVRF), personality traits, coping style and adverse life-events.
Data stemmed from a population-based cohort including 3618 participants (female 53%, n=1918; mean age 50.9 years, s.d. 8.8 years). Among them 563 had a lifetime history of chronic MDD, 1060 of non-chronic MDD and 1995 of no mood disorder. Diagnostic and FH information were elicited through semi-structured interviews, CVRF were assessed through physical investigations.
The major findings were that chronic MDD was associated with increase in appetite/weight and suicidal ideation/attempts during the most severe episode, higher exposure to life-events in adulthood, higher levels of neuroticism, lower levels of extraversion and lower levels of informal help-seeking behavior but less frequent FH of MDD compared to non-chronic MDD.
Chronic MDD is associated with a series of potential modifiable risk factors which are accessible via psychotherapeutic approaches that may improve the course of chronic MDD.