Physical comorbidity needs special attention in depressed patients who frequently do not understand the complex interrelationship between depression and physical comorbidity. Consequently, we investigated whether the burden of comorbidity and its relevance on general hospital mortality differed between patients with- and without depressive disorders in a 12-year follow-up in general hospital admissions.

During 2000 - 2012, 9,604 patients with (unipolar) major depression were admitted to three General Manchester Hospitals. All comorbidities with a prevalence ≥ 1% were compared with those of 96,040 age- and gender matched hospital controls. Comorbidities that were predictors for inpatient mortality were identified using multivariate logistic regression analyses.

Compared with hospital controls, depressed patients had a substantial higher burden of comorbidity and a more severe course. The highest comorbidities included hypertension, asthma, and anxiety disorders. Subsequently, twenty-six other diseases were disproportionally increased. In deceased depressed patients chronic obstructive pulmonary disease (COPD) and type 2 diabetes mellitus (T2DM) were the most frequently recorded comorbidities, contributing to 18.6% and 17.1% of hospital deaths. Further predictors of in-patient mortality included fifteen other physical conditions, many of them linked to diabetic complications. There were no differences in their impact on mortality compared to controls with the same comorbidities.

In general hospitals clinically relevant depressed patients succumb to the same physical diseases as their age-gender matched peers without depression. COPD and T2DM may need special attention in depressive disorders. Prospectively, it has to be investigated why depressed patients have more physical diseases than non-depressed patients.