Mortality of subjects with mood disorders in the Lundby community cohort: a follow-up over 50 years.

AIMS

To compare causes of death and mortality among subjects with and without mood disorder in the Lundby Cohort and to analyse additional mental disorders as risk factors for mortality in subjects with mood disorders.

BACKGROUND

The Lundby study is a longitudinal study that investigated mental health in an unselected population. The study commenced in 1947; the population was further investigated in 1957, 1972, and 1997.

METHODS

Experienced psychiatrists performed semi-structured diagnostic interviews, and best estimate consensus diagnoses of mental disorders were assessed at each field investigation. Subjects with mood disorder (n=508, 195 males, 313 females) were identified until 1997. Causes and dates of death between 1947 and 2011 were obtained from the Swedish cause of death register and were compared between subjects diagnosed with mood disorder and other participants. Mortality was compared between those with mood disorders and the remaining cohort with Cox regression analyses. Other mental disorders were considered as risk factors for death for subjects with mood disorders.

RESULTS

The hazard ratio for mortality in mood disorders was HR=1.18. However, the mortality was elevated only for males, HR=1.5. Comorbid anxiety disorders, organic disorders, dementia and psychotic disorders were significant risk factors for death. A total of 6.3% of the participants with mood disorder and 1.2% of the remaining participants committed suicide.

CONCLUSIONS

As expected, the suicide rate was higher among participants with mood disorders. Only males with mood disorders had elevated mortality. The impact on mortality from other mental disorders seems to vary between the genders.