@Article{info:doi/10.2196/12814,
author="Cormack, Francesca
and McCue, Maggie
and Taptiklis, Nick
and Skirrow, Caroline
and Glazer, Emilie
and Panagopoulos, Elli
and van Schaik, Tempest A
and Fehnert, Ben
and King, James
and Barnett, Jennifer H",
title="Wearable Technology for High-Frequency Cognitive and Mood Assessment in Major Depressive Disorder: Longitudinal Observational Study",
journal="JMIR Ment Health",
year="2019",
month="Nov",
day="18",
volume="6",
number="11",
pages="e12814",
keywords="depression; cognition; mood; mobile health; mHealth; mobile apps; ecological momentary assessment; digital phenotyping; digital biomarkers",
abstract="Background: Cognitive symptoms are common in major depressive disorder and may help to identify patients who need treatment or who are not experiencing adequate treatment response. Digital tools providing real-time data assessing cognitive function could help support patient treatment and remediation of cognitive and mood symptoms. Objective: The aim of this study was to examine feasibility and validity of a wearable high-frequency cognitive and mood assessment app over 6 weeks, corresponding to when antidepressant pharmacotherapy begins to show efficacy. Methods: A total of 30 patients (aged 19-63 years; 19 women) with mild-to-moderate depression participated in the study. The new Cognition Kit app was delivered via the Apple Watch, providing a high-resolution touch screen display for task presentation and logging responses. Cognition was assessed by the n-back task up to 3 times daily and depressed mood by 3 short questions once daily. Adherence was defined as participants completing at least 1 assessment daily. Selected tests sensitive to depression from the Cambridge Neuropsychological Test Automated Battery and validated questionnaires of depression symptom severity were administered on 3 occasions (weeks 1, 3, and 6). Exploratory analyses examined the relationship between mood and cognitive measures acquired in low- and high-frequency assessment. Results: Adherence was excellent for mood and cognitive assessments (95{\%} and 96{\%}, respectively), did not deteriorate over time, and was not influenced by depression symptom severity or cognitive function at study onset. Analyses examining the relationship between high-frequency cognitive and mood assessment and validated measures showed good correspondence. Daily mood assessments correlated moderately with validated depression questionnaires (r=0.45-0.69 for total daily mood score), and daily cognitive assessments correlated moderately with validated cognitive tests sensitive to depression (r=0.37-0.50 for mean n-back). Conclusions: This study supports the feasibility and validity of high-frequency assessment of cognition and mood using wearable devices over an extended period in patients with major depressive disorder. ",
issn="2368-7959",
doi="10.2196/12814",
url="https://mental.jmir.org/2019/11/e12814",
url="https://doi.org/10.2196/12814",
url="http://www.ncbi.nlm.nih.gov/pubmed/31738172"
}