This study examines the effects of mobility and cognition on mortality risk in women late in life.Methods:
A prospective study was conducted among 1,495 women (mean age 87.6 years) participating in the Study of Osteoporotic Fractures Year 20 examination (2006–2008). Mobility (ascertained by Short Physical Performance Battery [SPPB]) was categorized as poor (SPPB 0–3, n = 312), intermediate (SPPB 4–9, n = 799), or good (SPPB 10–12, n = 384). Cognitive status (adjudicated based on neuropsychological tests) was classified as normal ( n = 873), mild cognitive impairment ( n = 354), or dementia ( n = 268). Deaths ( n = 749) were identified from Year 20 through July 31, 2014 (average follow-up 4.9 years).Results:
There was not strong evidence of an interaction between mobility and cognition for prediction of mortality risk ( p interaction term .16). Compared to women with good mobility, mortality risks were increased among women with intermediate mobility (hazard ratio [HR] 1.26, 95% confidence interval [CI] 1.02–1.57) and those with poor mobility (HR 1.64, 95% CI 1.24–2.16) after consideration of cognition and other mortality risk factors. Similarly, mortality risks were higher among women with mild cognitive impairment (HR 1.46, 95% CI 1.21–1.76) and those with dementia (HR 1.88, 95% CI 1.54–2.31) compared to women with normal cognition after consideration of mobility and other mortality risk factors.Conclusions:
Among women late in life, 5-year mortality risk was substantially increased among women with deficits in mobility even after accounting for cognition and traditional prognostic indicators. Similarly, deficits in cognition were associated with increased 5-year mortality despite consideration of mobility and conventional risk factors.