Disequilibrium in older people: a prospective study.

Objective: To identify the clinical and neuroimaging features in older people with disequilibrium of unknown cause.

Background: Many older people show a deterioration of balance without an identifiable cause. Whether the disequilibrium is a normal aging phenomenon, the result of yet unidentified neuropathology, or a combination of the two is unknown.

Methods: Twenty-nine patients who complained of disequilibrium (ages 75 to 92) and 29 age- and sex-matched control subjects completed five yearly examinations including history and semiquantitative neurologic examination, activities of daily living, visual acuity, mini-mental status, bedside gait and balance score (Tinetti), Purdue pegboard, and vestibular function testing. Concerns about falling and number of falls were quantified. Subcortical white matter lesions (WML) and frontal atrophy (FA) were graded (blindly), and the ventricular-brain ratio (VBR) was measured from MRIs of the brain.

Results: On entry, patients differed from control subjects only in measures of balance, concerns about falling, and falls. Over the 5 years, patients were four times more likely to fall than control subjects. The number of falls was highly correlated with measures of balance (p < 0.001). The VBR as well as the frequency of WML and FA were all significantly (p < 0.001) greater in patients than in control subjects.

Conclusion: Disequilibrium of unknown cause in older people is associated with frequent falls, concerns about falling, brain atrophy, and WML on MRI. Some cases are probably caused by small-vessel ischemic disease.