Lower Extremity Motor Function and Disability in Mild Cognitive Impairment

Abstract

Recent findings suggest that lower extremity motor dysfunction may be a feature of mild cognitive impairment (MCI), but little is known about the nature and significance of lower extremity motor dysfunction in MCI. The aim of this study was to examine the extent to which MCI is associated with impaired gait, balance, and strength and to examine the relation of lower extremity function to disability among persons with MCI in the Rush Memory and Aging Project, a clinical-pathologic study of common chronic conditions of old age. In a series of analyses adjusted for age, sex, and education, individuals with MCI exhibited more impaired gait and balance than individuals without cognitive impairment. Because vascular factors can contribute to lower extremity motor dysfunction, the authors repeated the initial analyses including terms for vascular risk factors and vascular disease, and the associations between MCI and lower extremity motor dysfunction persisted. Moreover, among those with MCI, impairments in gait and balance were associated with an increased likelihood of disability. These findings suggest that lower extremity motor dysfunction is common and contributes to disability in MCI, but lower extremity motor dysfunction in MCI does not appear to be explained by the vascular factors examined in this study.

This research was supported by National Institute on Aging grants R01AG17917 and K23 AG23040. The authors are grateful for the altruism and support of the many Illinois residents from the following facilities participating in the Memory and Aging Project: Fairview Village, Downers Grove; The Holmstead, Batavia; Covenant Village, Northbrook; Wyndemere, Wheaton; Francis Manor, Des Plaines; Friendship Village, Schaumberg; Peace Village, Palos Park; Washington Jane Smith, Chicago; Garden House Apartments, Calumet City; Victorian Village, Homer Glen; King Bruwaert, Burr Ridge; The Breakers of Edgewater; The Imperial, Chicago; Victory Lakes, Lindenhurst; Windsor Park Manor, Carol Stream; Fanciscan Village, Lemont; Rennaissance, Chicago; Alden of Waterford, Aurora; Elgin Housing Authority; The Oaks, Oak Park; Bethlehem Woods, LaGrange Park; Luther Village, Arlington Heights; St. Paul's Home, Chicago; Marion Village, Home Glen; Holland Home, South Holland; Village Woods, Crete; Laurence Manor, Matteson; Trinity, Chicago; St. Andrew's Phoenix, Phoenix; The Moorings, Arlington Heights; Mayslake, Oak Brook; The Birches, Clarendon Hills; Cedar Village, Arlington Heights; Kingston Manor, Chicago; Community Renewal Senior Ministry, Chicago; and the residents of the Chicago metropolitan area. We also thank Traci Colvin, MPH, and Tracy Hagman for study coordination; Pam Smith, Barbara Eubeler, Karen Lowe Graham, and Mary Futrell for study recruitment; George Dombrowski and Greg Klein for data management; and the entire staff of the Rush Alzheimer's Disease Center and Memory and Aging Project.

Notes

∗p values based on t tests comparing those with and without MCI.

∗Estimates based on linear regression models adjusted for age, sex, and education.