Patient-centric assessment of rheumatoid arthritis using a smartwatch and bespoke mobile app in a clinical setting

Abstract

Rheumatoid arthritis (RA) is a fluctuating progressive disease requiring frequent symptom assessment for appropriate management. Continuous tracking using digital technologies may provide greater insights of a patient's experience. This prospective study assessed the feasibility, reliability, and clinical utility of using novel digital technologies to remotely monitor participants with RA. Participants with moderate to severe RA and non-RA controls were monitored continuously for 14 days using an iPhone with an integrated bespoke application and an Apple Watch. Participants completed patient-reported outcome measures and objective guided tests designed to assess disease-related impact on physical function. The study was completed by 28 participants with RA, 28 matched controls, and 2 unmatched controls. Completion rates for all assessments were > 97% and were reproducible over time. Several guided tests distinguished between RA and control cohorts (e.g., mean lie-to-stand time [seconds]: RA: 4.77, control: 3.25; P < 0.001). Participants with RA reporting greater stiffness, pain, and fatigue had worse guided test performances (e.g., wrist movement [P < 0.001] and sit-to-stand transition time [P = 0.009]) compared with those reporting lower stiffness, pain, and fatigue. This study demonstrates that digital technologies can be used in a well-controlled, remote clinical setting to assess the daily impact of RA.

Figure 1

Correlations between lie-to-stand time and fatigue (a), stiffness (b), and lower body JMAP score (c). R² values calculated using Spearman’s rank correlation. One-way ANOVA was used to compare differences in guided test performances and PRO measures. One-way ANOVA post hoc analyses were used to compare differences in guided tests between groups based on symptom severity as determined by PRO measures (*P < 0.05, **P < 0.01, ***P < 0.001). ^†Fatigue was assessed through a single-item question asking participants to rate their worst level of fatigue over the past 24 h on a 10-point scale, ranging from “no fatigue” (0) to “as bad as you can imagine” (10). FACIT-Fatigue questionnaire was administered only on Days 1, 7, and 14, hence the fewer data points compared to stiffness and lower body JMAP score plots; ^‡stiffness was assessed using a single-item question on the severity of morning stiffness experienced by the participant on a given day, with 5 response options provided, ranging from no stiffness (0) to very severe (4); ^§lower body JMAP score was calculated by summing the scores for each hip, knee, and ankle joint (left and right; total = 6), plus the average score of all foot joints (10 joints per foot) and dividing by 2. Score could range from a minimum of 0 to a maximum of 12 (maximum reached in study was 8). ANOVA analysis of variance, FACIT-Fatigue functional assessment of chronic illness therapy—fatigue, JMAP joint-pain map, PRO patient-reported outcome, RA rheumatoid arthritis, s seconds.

Figure 2

Study design. JMAP joint-pain map, PROM patient-reported outcome measure, RA rheumatoid arthritis, VAS visual analog scale.