[A same deficit of cognitive inhibition in early and late-onset depression in elderly women: a pilot study]

Late-life depression has been associated with frontostriatal abnormalities that are thought to lead to deficits of cognitive inhibition. However, it remains unclear, whether age-of-onset identifies subgroups of depression. The objective of this study was to compare cognitive inhibition in depressed women aged 60 and older, according to age of the first onset depression (before or after 60 years old).

We compared 10 currently depressed women (HDRS-17≥18) with a late-onset depression to 10 depressed women with an early-onset depression, and to 10 healthy controls. We examined cognitive inhibition (Stroop, Hayling, Go/No-Go), shifting (TMT), updating in working memory (WAIS) and executive functions (BREF). All groups were matched for age, education level, and MMSE score (MMSE≥24).

Depressed elderly women with a late and an early-onset depression had a greater impairment in executive functions and cognitive inhibition compared with healthy controls (p<0,001), but without significant differences according to the age of the first onset depression. Futhermore, late-onset depression in women was significantly correlated with a deficit of cognitive inhibition (rs=0.55; p=0.012).

Cognitive inhibition should be assessed in late-life depression. Interventions may be developed to specifically target cognitive impairment in the prevention of late-life depression, to identify those who are the most vulnerable to relapse.