A longitudinal study of gait and balance dysfunction in normal older people.

OBJECTIVE: To identify the causes of deteriorating gait and balance in normal older people.
METHODS: We measured visual acuity, vestibulo-ocular responses, pure-tone hearing levels, vibration sense, deep tendon reflexes, and Tinetti gait and balance scores in 59 normal older subjects (mean +/- SD age on entry, 78.5 +/- 3.7 years) followed up at yearly examinations (range, 8-10 years). White matter hyperintensities on magnetic resonance imaging taken in mid follow-up were graded qualitatively and quantitatively.
RESULTS: For each variable except white matter hyperintensities, we calculated a normalized change per year. There was a significant (P<.05) age-related decrease in vestibulo-ocular reflex gain at 0.05 and 0.20 Hz but not at 0.80 Hz, an increase in pure-tone hearing thresholds (at 1, 2, 4, and 8 kHz), a decrease in vibration sense and deep tendon reflexes in the feet, and a decrease in total Tinetti score. However, only changes in vibration sense in the feet and hearing at 1 kHz were significantly correlated (Spearman rank correlation) with the change in Tinetti score. White matter hyperintensities on magnetic resonance imaging had a higher correlation with the yearly change in Tinetti scores.
CONCLUSIONS: This longitudinal study showed age-related decreases in vestibular, visual, auditory, and somatosensation in normal older people, but these changes were only weakly correlated with changes in gait and balance. White matter hyperintensities on magnetic resonance imaging were more highly correlated with changes in gait and balance, but all variables together accounted for only about 29% of the measured change in gait and balance.