Static balance impairments under dual-task conditions in MCI

(ETCO 2) was recorded simultaneously. Stepwise multiple linear regression analysis was used to examine the effects of MAP, ET CO 2, group (0 for control, 1 for MCI), age and gender (0 for female, 1 for male) on VMCA, F ICA, and F VA (, percentage changes to baseline).Results: The range of variations inMAP induced by drug infusionwas 65w143mmHg associatedwith a concomitant change in ETCO2 (range: 22w48 mm Hg). The regression equations derived were: VMCA 1⁄4 0.170*MAP + 0.530* ETCO2 + 0.189*Group + 0.252*Age, R 1⁄4 0.719, P < 0.001; FICA 1⁄4 0.212* ETCO2, R 1⁄4 0.237, P < 0.01; FVA 1⁄4 0.221*MAP + 0.262* ETCO2 + 0.256*Group, R 1⁄4 0.475, P < 0.001. Significantly different CBF responses to MAP and ETCO2 between the MCI and control groups were observed in the MCA and VA, but not in the ICA. No gender differences were observed.Conclusions: Cerebral autoregulatory dysfunction was detected in patients with MCI, most prominently in the MCA and posterior cerebral territory (supplied mainly by the VA). These findings suggest that cerebrovascular dysfunction is detectable at the early stage of AD. A cause-effect relationship has yet to be established.