OBJECTIVES: Intraindividual variability (IIV) refers to the variation in reaction time (RT) performance across a given cognitive task. As greater IIV may reflect compromise of the frontal circuitry implicated in falls and gait impairment in older adults, we conducted a systematic review of the literature relating to this issue. METHODS: Searches were conducted of electronic databases that identified empirical investigations of IIV, falls, and gait in older adult samples with a mean age of 65 years or older. Data were extracted relating to IIV measures, study population, and outcomes. RESULTS: Of 433 studies initially identified, 9 met inclusion criteria for IIV and falls (n = 5), and gait (n = 4). Representing a total of 2,810 older participants, all of the studies of IIV and falls showed that elevated variability was associated with increased risk of falling, and half of the studies of gait indicated greater IIV was related to gait impairment. DISCUSSION: Across studies, IIV measures were consistently associated with falls in older persons and demonstrated some potential in relation to gait. IIV metrics may, therefore, have considerable potential in clinical contexts and supplement existing test batteries in the assessment of falls risk and gait impairment in older populations.
OBJECTIVES: Intraindividual variability (IIV) refers to the variation in reaction time (RT) performance across a given cognitive task. As greater IIV may reflect compromise of the frontal circuitry implicated in falls and gait impairment in older adults, we conducted a systematic review of the literature relating to this issue. METHODS: Searches were conducted of electronic databases that identified empirical investigations of IIV, falls, and gait in older adult samples with a mean age of 65 years or older. Data were extracted relating to IIV measures, study population, and outcomes. RESULTS: Of 433 studies initially identified, 9 met inclusion criteria for IIV and falls (n = 5), and gait (n = 4). Representing a total of 2,810 older participants, all of the studies of IIV and falls showed that elevated variability was associated with increased risk of falling, and half of the studies of gait indicated greater IIV was related to gait impairment. DISCUSSION: Across studies, IIV measures were consistently associated with falls in older persons and demonstrated some potential in relation to gait. IIV metrics may, therefore, have considerable potential in clinical contexts and supplement existing test batteries in the assessment of falls risk and gait impairment in older populations.
Authors: Laura J E Brown; Tim Adlam; Faustina Hwang; Hassan Khadra; Linda M Maclean; Bridey Rudd; Tom Smith; Claire Timon; Elizabeth A Williams; Arlene J Astell Journal: Age (Dordr) Date: 2016-07-29
Authors: Andreas W Blomkvist; Fredrik Eika; Martin T Rahbek; Karin D Eikhof; Mette D Hansen; Malene Søndergaard; Jesper Ryg; Stig Andersen; Martin G Jørgensen Journal: PLoS One Date: 2017-12-29 Impact factor: 3.240
Authors: Nicole A Kochan; David Bunce; Sarah Pont; John D Crawford; Henry Brodaty; Perminder S Sachdev Journal: PLoS One Date: 2017-08-09 Impact factor: 3.240