People with Parkinson's disease exhibit deficits in gait, speech and dexterity.• The usability of a mobile health (mHealth) smartphone application designed to target symptoms of gait, speech and dexterity in Parkinson's disease was investigated. • Primary outcome measures included adherence, gait characteristics, number of steps per day, sustained phonation, speech prosody and the 9-hole peg test. • Adherence to the mHealth application was moderate and there was little effect on gait, speech and dexterity.• Increased adherence to mHealth treatment was not associated with improved outcomes.• User-friendly mHealth to complement traditional rehabilitation may improve efficacy.Aim: This study investigated the usability of a mobile health (mHealth) smartphone application to treat gait, speech and dexterity in people with Parkinson's disease. Methods: Participants either used an mHealth application (intervention) or maintained their normal routine (control) for 12 weeks and were evaluated at baseline and post-test time points for primary outcome measures of adherence, gait, speech and dexterity. mHealth application adherence was compared with percent change scores on gait, speech and dexterity measures. Results: Adherence was moderate and there were no significant group, time or interaction effects for any outcome measures. Correlations between adherence and outcomes were weak and negative. Conclusion: These data suggest that usability of this mHealth application was limited as indicated by low adherence. The application alone in its present form was not adequate to treat symptoms of gait, speech or dexterity in people with Parkinson's disease.

While all participants had significantly slower and shorter backward velocity and stride length, respectively, the exercise intervention had no effect. Similarly, BOLD signal during MI did not change with exercise; however, freezers had significantly lower BOLD signal during IMG-BWD compared to non-freezers. This suggests potential decreased recruitment of the SMN during MI of gait in freezers.

In persons with asymptomatic HIV infection, electrophysiologic tests may be the most sensitive indicators of subclinical neurologic impairment. Electrophysiologic abnormalities are far more common in asymptomatic carriers of HIV than in controls and tend to progress over time.

Objectives Based on multi‐domain classification of Parkinson disease (PD) subtypes, we sought to determine the key features that best differentiate subtypes and the utility of PD subtypes to predict clinical milestones. Methods Prospective cohort of 162 PD participants with ongoing, longitudinal follow‐up. Latent class analysis (LCA) delineated subtypes based on score patterns across baseline motor, cognitive, and psychiatric measures. Discriminant analyses identified key features that distinguish subtypes at baseline. Cox regression models tested PD subtype differences in longitudinal conversion to clinical milestones, including deep brain stimulation (DBS), dementia, and mortality. Results LCA identified distinct subtypes: “motor only” (N = 63) characterized by primary motor deficits; “psychiatric & motor” (N = 17) characterized by prominent psychiatric symptoms and moderate motor deficits; “cognitive & motor” (N = 82) characterized by impaired cognition and moderate motor deficits. Depression, executive function, and apathy best discriminated subtypes. Since enrollment, 22 had DBS, 48 developed dementia, and 46 have died. Although there were no subtype differences in rate of DBS, dementia occurred at a higher rate in the “cognitive & motor” subtype. Surprisingly, mortality risk was similarly elevated for both “cognitive & motor” and “psychiatric & motor” subtypes compared to the “motor only” subtype (relative risk = 3.15, 2.60). Interpretation Psychiatric and cognitive features, rather than motor deficits, distinguish clinical PD subtypes and predict greater risk of subsequent dementia and mortality. These results emphasize the value of multi‐domain assessments to better characterize clinical variability in PD. Further, differences in dementia and mortality rates demonstrate the prognostic utility of PD subtypes.

People with Parkinson disease demonstrate increased gait variability, but the primary variability sources are poorly understood. People with Parkinson disease and freezing of gait (freezers) have greater gait impairments than people with Parkinson disease without freezing of gait (nonfreezers), which may relate to cerebellar dysfunction. Thirteen freezers and 31 nonfreezers completed backward, forward, and forward with dual task gait trials. Sagittal joint angle waveforms were extracted for the hip, knee, and ankle using 3D motion capture. Decomposition indices were calculated for the 3 joint combinations. Principal component analysis extracted variance sources from the joint waveforms. Freezers had significantly greater decomposition between hip–ankle (F1,42 = 5.1, P = .03) and hip–knee (F1,42 = 5.3, P = .03) movements. The principal component analysis did not differentiate freezers and nonfreezers; however, primary variance sources differed between conditions. Primary variance during forward and forward with dual task gait came from joint angle magnitude and peak angle timing. Backward gait showed primary variance from joint angle magnitude and range of motion. The results show that freezers decompose movement more than nonfreezers, implicating cerebellar involvement in freezing of gait. Primary variance differs between gait conditions, and tailoring gait interventions to address variability sources may improve intervention efficacy.