Postural stability is a multi-factorial skill maintained implicitly. Components of quiet standing can decline with Alcohol Use Disorder (AUD), cause instability, and disrupt activities of daily living (ADL). To examine how stability factors contribute to ADL and balance, 638 force platform testing sessions measured sway paths acquired during quiet standing in 151 AUD and 96 control men and women, age 25-75. Structural equation (seq) path analysis estimated contributions from age, diagnosis, and sensory perception to sway and measures of ADL and roadside ataxia testing. Whether eyes were open or closed, older AUD and control participants had longer sway paths than younger ones; older men had longer sway paths than older women. Although each sensory ability tested declined with aging, different factor constellations influenced ADL, ataxia scores, or sway path. Seq-path analysis indicated that ADL was strongly dependent on sensory (but not cognitive) systems with sway-path length accounting for upwards of 25% of variance. Within the AUD group, an index of historically-experienced withdrawal symptoms was a common predictor of stability regardless of vision condition. The greatest variance measured by the seq-path model was for predicting platform sway and simple ataxia testing of one-leg standing even though these measures were affected by different predictor variables: strong predictors of one-leg standing were diagnosis and age (R = 39.6%-43.2%), whereas strong predictors of sway-path length were sensory factors and withdrawal index (R = 22.0%-22.9%). These findings present evidence for appreciating selective factors that contribute to declining postural stability and to liability for compromised quality of life in AUD.
© 2020 Society for the Study of Addiction.

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