How to early recognize mood disorders in primary care: A nationwide, population-based, cohort study

Background: Mood disorders are managed predominantly in primary care. However, general practitioners’ (GPs) ability to detect and diagnose patients with mood disorders is still considered unsatisfactory. The aim of the present study was to identify predictors for the early recognition of depressive disorder (DD) and bipolar disorder (BD) in general practice.
Methods: A cohort of 1,144,622 patients (605,285 women, 539,337 men) was investigated, using the Health Search IMS Health Longitudinal Patient Database. Predictors of DD or BD were identified at baseline encompassing somatization-related features, lifestyle variables, medical and psychiatric comorbidities. Patients were followed up as long as the following events occurred: diagnoses of DD or BD, death, end of the registration with the GP, end of the study period.
Results: We found an incidence rate of DD or BD of 53.61 and 1.5 per 10,000 person-years, respectively. For both the conditions, the incidence rate grew with age. Most of the lifestyle variables and medical comorbidities increased the risk of mood disorders. The strongest effect was found for migraine/ headache (HR [95% CI] = 1.32 [1.26–1.38]), fatigue (1.32 [1.25–1.39]) irritable bowel syndrome (1.15 [1.08-1.23]), and pelvic inflammation disease (1.28 [1.18–1.38]).
Conclusions: Several predictors, in particular somatic symptoms, could be interpreted as an early sign of a mood disorder, and represent a valid indication for the GPs diagnostic process of mental disorders.