Dual Sensory Impairment and Cognitive Decline: The Results From the Shelter Study.

OBJECTIVES To examine whether nursing home residents with concurrent vision and hearing impairment, dual sensory impairment (DSI), have a greater cognitive decline over time than do those without sensory impairment and whether social engagement modifies this association. METHODS Based on the Services and Health for Elderly in Long TERm Care study, 1,989 nursing home residents who were assessed using the interRAI LTCF at 6-month intervals over 1 year were included. Multivariate linear regression models with time-variant exposure variables of sensory impairment and social engagement using generalized estimating equations were performed to predict cognitive function measured by the Cognitive Performance Scale (range 0-6). RESULTS Residents with DSI had a greater cognitive decline [changes in Cognitive Performance Scale over 1 year = 1.12 (95% confidence interval = 0.81:1.42)] compared to those with either vision or hearing impairment [0.67 (0.53:0.64)] and those without sensory impairment [0.56 (0.48:0.64)]. A lower level of social engagement was also associated with a greater cognitive decline. The combined exposure variable of sensory impairment and social engagement revealed the greatest cognitive decline for socially disengaged residents with DSI [1.87 (1.24:2.51)] and the potential effect modification of social engagement on the association between DSI and cognitive decline; DSI was not associated with a greater cognitive decline among socially engaged residents, while it was associated among socially disengaged residents DISCUSSION Cognitive function declines faster in nursing home residents with DSI only when residents were not socially engaged. Therefore, residents with DSI might cognitively benefit from interventions to improve involvement in social life at nursing homes.