Reversible states of physical and/or cognitive dysfunction: A 9-year longitudinal study

Objectives

To determine 1) age-adjusted transition probabilities to worsening physical/cognitive function states, reversal to normal cognition/physical function, or maintenance of normal state; 2) whether these transitions are modulated by sex, BMI, education, hypertension (HTN), health status, or APOE4; 3) whether worsening gait speed preceded cognition change, or vice versa.

Design

Analysis of 9-year prospective cohort data from the New Mexico Aging Process Study. Setting: Healthy independent-living adults. Participants: 60+ years of age (n= 598).

Measurements

Gait speed, cognitive function (3MSE score), APOE4, HTN, BMI, education, health status.

Results

Over 9 years, 2129 one-year transitions were observed. 32.6% stayed in the same state, while gait speed and cognitive function (3MSE scores) improved for 38% and 43% of participants per year, respectively. Transitions to improved function decreased with age (P<0.001), APOE4 status (P=0.02), BMI (P=0.009), and health status (P=0.009). Transitions to worse function were significantly increased for the same factors (all P<0.05). Times to lower gait speed and cognitive function did not precede each other (P=0.91).

Conclusions

Transitions in gait speed and cognition were mutable with substantial likelihood of transition to improvement in physical and cognitive function even in oldest-old, which may have clinical implications for treatment interventions.