The assessment of cognition in visually impaired older adults

Background: visual and cognitive impairments are common in later life. Yet there are very few cognitive screening tests for the visually impaired. Objective: to screen for cognitive impairment in the visually impaired. Methods: case-control study including 150 elderly participants with visual impairment (n=74) and a control group without visual impairment (n=76) using vision-independent cognitive tests and cognitive screening tests (MMSE and clock drawing tests (CDT)) which are in part vision dependent. Results: the scoring of the two groups did not differ in the vision-independent cognitive tests. Visually impaired patients performed poorer than controls in the vision-dependent items of the MMSE (T=7.3; df: 148; P<0.001) and in CDT (T=3.1; df: 145; P=0.003). No group difference was found when vision-independent items were added to MMSE and CDT. The test score gain by the use of vision-independent items correlated with the severity of visual impairment (P