VISUAL IMPAIRMENT PREDICTS PHYSICAL FUNCTION DECLINE: THE HEALTH, AGING, AND BODY COMPOSITION (HEALTH ABC) STUDY

The relationship between visual impairment (VI) and decline in physical function with age is poorly understood. We constructed separate linear mixed models to evaluate the relationship of self-reported (visual function question (VFQ) score) or performance-based (visual acuity (VA); log contrast sensitivity (LCS); stereoacuity (SA)) VI with change in performance on the Short Physical Performance Battery (SPPB) over 8 years in 2219 Health ABC participants. Mean age was 75.5 years (range 71-82); 52.4% were female, and 37.4% were black. For all measures of visual function, better vision was associated with loss of approximately -0.3 SPPB units/year which was similar to the unadjusted change in SPPB over time (-0.328 units/year 95%CI (-0.35, -0.31)). Participants with LCS ≤1.3 log units experienced 58% faster rate of decline versus those with better LCS (test of difference in slopes p< 0.0001). Those with poor VA ≥20/50 showed a 50% greater decline in SPPB (p=0.0029), and those with low SA ≤85 arcsec demonstrated a 33% faster decline (p< 0.001) relative to those with better visual function. Compared to the slope at the mean VFQ score, a 1 standard deviation lower score was associated with 23% greater decline in SPPB (p< 0.0001). The difference in SPPB slopes remained significant across VI measures after adjusting for longitudinal decline associated with age, sex, and black race (all p< 0.05). Both self-reported and performance-based VI predicted faster declines in SPPB over time. Whether older adults with VI might benefit from targeted intervention to prevent declining mobility function remains to be evaluated.