Objective, more precise, longitudinal tracking of HD signs and symptoms through frequent, ecologically valid, at-home testing promises to augment standard clinical testing methods. Standard methods may fail to capture natural symptom fluctuations and be influenced by inter-rater variability, and the clinical visit itself.

Average adherence was high, with 80% of all active tests performed each week in the first 20 weeks. The test-retest reliability of active tests ranged from 0.74–0.97, median 0.95. Digital versions of standard in-clinic tests showed strong correlations ranging from r=0.69 (P <0.001, Stroop Word Reading) to r=0.86 (P <0.001, Speeded Tapping). Active tests showed good correlations with established clinical motor measures, ranging from r=0.34 (P=0.03, U-Turn) to r=0.64 (P <0.001, Chorea, non-dominant hand). Updated results from ongoing data collection will be presented.

The results suggest that frequent remote patient monitoring yields reliable and valid measures of cognition and motor symptoms in HD when compared with standard clinical measures. The digital biomarker smartphone application has potential to improve measurement of disease progression in HD.