TABLE 2.

Mixed effects model for outcome of frailty

Covariates	Estimate	95% Confidence interval – lower limit	95% Confidence interval – upper limit	p value
Time (years since baseline)	0.019	0.017	0.020	<0.0001
Sex (female)	−0.057	−0.078	−0.036	0.001
Education (years)	−0.002	−0.005	0.002	0.310
Time in Study	−0.018	−0.021	−0.015	<0.001
Clinical diagnosis
MCI a vs. NCI b	0.018	−0.008	0.043	0.170
Dementia vs. NCI	0.032	−0.006	0.058	0.015
Neuropathological Index (per 0.01)	0.022	−0.042	0.086	0.510
Time*Clinical diagnosis
Time*MCI	0.005	0.003	0.008	<0.0001
Time*Dementia	0.020	0.018	0.023	<0.0001

In this study of how changes in the degree of frailty affected the probability of a diagnosis of Alzheimer's dementia, we highlight two key findings: (1) frailty increased at a rate of approximately one deficit per year in a sample of older adults from retirement communities in the USA; and (2) people who ultimately developed MCI or Alzheimer's dementia became frailer more quickly than those who did not, regardless of their neuropathological burden. These results underscore the importance of addressing frailty to manage dementia risk.

^a Mild cognitive impairment.

^b No cognitive impairment.