A population study on the influence of depression on neuropsychological functioning in 85-year-olds

Objective: To examine cognitive function in very old depressed individuals. Method: Individuals with major depression (MDS) or dysthymia according to t he DSM-III-R were compared to mentally healthy regarding tests of verbal ab ility, inductive logical reasoning, spatial ability, perceptual speed, basi c arithmetics, primary memory and secondary memory in a population-based sa mple of 85-year-olds. Results: Individuals with MDS performed worse than mentally healthy individ uals in tests of verbal ability, inductive logical reasoning, spatial abili ty, perceptual speed and secondary memory. There were no differences betwee n the groups regarding basic arithmetics and primary memory. The poor test performance was mainly associated with psychomotor retardation and decrease d concentration in depressed individuals. Memory complaints were not correl ated to poor test performance, neither in the mentally healthy nor in the d epressed. Conclusion: MDS in elderly individuals is associated with reduced cognitive test performance, especially regarding more complex and time-demanding tes ts and in tests of secondary memory.