BACKGROUND: The aim of this study was to find clinical characteristics that can identify elderly patients with depression at risk for suicidal ideation and to determine their prognosis.

METHOD: Suicidal ideation, past suicidal behavior, severity of depression, cognitive impairment, medical burden, disability, and social support were studied in 354 patients with depression aged 61 to 93 years. The patients had in-person evaluations every 6 months and telephone evaluations for a mean of 1.8 years (SD, 2.2).

RESULTS: During the index episode, suicidal ideation was predicted by previous suicide attempts with serious intent (odds ratio [OR], 2.82; 95% confidence interval [CI], 1.37-5.80), severity of depression (OR, 1.09; 95% CI, 1.03-1.16), and poor social support (OR, 1.77; 95% CI, 1.18-2.65). Suicide attempts during the year prior to entry were reported by patients with a severe index episode (OR, 1.05; 95% CI, 1.00-1.11), impaired instrumental activities of daily living (OR, 0.78; 95% CI, 0.67-0.93), and limited impairment in activities of daily living (OR, 1.53; 95% CI, 1.10-2.14). At the initial evaluation, severity of depression, previous attempts, and seriousness of suicidal intent during previous attempts predicted the course of suicidal ideation (concordance correlation, 0.78). During follow-up, contemporaneous severity of depression was the most important determinant of suicidal ideation over time (concordance correlation, 0.88).

CONCLUSIONS: Elderly individuals with severe depression, history of suicide attempts with serious intent, and poor social support are most likely to have suicidal ideation and should be targeted for appropriate interventions. Severity of depression is the strongest predictor of the course of suicidal ideation.