The risk of affective disorders in patients with adrenocortical insufficiency

OBJECTIVE: To investigate the risk of affective disorders among patients hospitalised with adrenocortical insufficiency in the study period: 1977-1999. METHOD: Using data from Danish registers, two study cohorts were identified by their ICD diagnoses at discharge from hospital: one comprising all patients with a first hospital admission with an index diagnosis of adrenocortical insufficiency; the other a control cohort comprising all patients with a first hospital admission with an index diagnosis of osteoarthritis. Subsequent admissions to psychiatric hospital wards with discharge ICD diagnoses of affective disorders were used as events of interest. Rates of readmission were estimated using Poisson regression models in survival analyses. Age, sex, duration of time after index discharge, and calendar time were included as co-variables. The primary analysis included all patients with adrenocortical insufficiency. Thereafter, the subgroup of patients with primary adrenocortical insufficiency (Addison's disease) was investigated separately in a secondary analysis. RESULTS: A study sample of 989 patients with adrenocortical insufficiency and 124,854 patients with osteoarthritis was identified. Eight hundred and fifty-two patients were subsequently readmitted with a diagnosis of affective disorder. Patients with adrenocortical insufficiency had a 2.68 (95% CI: 1.62-4.42) times greater rate of affective disorders and a 2.12 (95% CI: 1.16-3.86) times greater rate of depressive disorder when compared with the rate for patients with osteoarthritis. Patients with Addison's disease had a 2.14 (95% CI: 1.14-4.03) times greater rate of affective disorders, and a 1.71 (95% CI: 0.81-3.63) times greater rate of depressive disorder compared with the rate of patients with osteoarthritis. CONCLUSION: Patients with adrenocortical insufficiency may be at increased risk of developing severe affective disorders. Conventional replacement therapy with hydrocortisone may not be sufficient to ensure the psychiatric well-being of these patients.