Adults with Congenital Heart Disease Move Well but Lack Intensity: A Cross-Sectional Study Using Wrist-Worn Physical Activity Trackers

Objective: This study compared objectively measured and self-reported physical activity (PA) in adults with congenital heart disease (ACHD) to a healthy reference cohort (RC). Patients and Methods: From May 2017 to August 2020, 211 ACHD (39.9 ± 9.7 years, 101 female) and 141 healthy adults (35.9 ± 14.7 years, 76 female) participated in a wearable-based and self-reported PA assessment. Moderate-to-vigorous PA (MVPA) and the step count were recorded with the Garmin vivofit^® 3 device for 7 consecutive days. Additionally, subjects were asked to report the number of days they are active for ≥30 min throughout the week. Results: Only 33 (17%) ACHD and 36 (26%) healthy controls (p = 0.030) accumulated the World Health Organization’s (WHO) recommendation of 150 min MVPA per week. ACHD were less active per week (ACHD: 40.0 [0.0; 101.0] min. MVPA vs. RC: 75.0 [22.5; 152.5] min. MVPA, p = 0.002) and walked fewer daily steps (ACHD: 8,246 [6,505; 10,434] vs. RC: 9,413 [7,621; 11,654], p = 0.001) than healthy controls. Especially, patients with moderate (p = 0.030), complex (p < 0.001), or surgically corrected (p = 0.008) congenital heart disease accumulated significantly less MVPA than healthy peers throughout the week. A large majority of 72% of ACHD and 58% of the RC overestimated their weekly active days by more than one day. Conclusions: ACHD walked quite a few steps daily but lacked intensity. ACHD was less active than healthy controls and failed to reach international recommendations. They therefore need encouragement toward more intense movement to improve the exercise capacity and lower cardiovascular risk. Self-reported PA showed no agreement to the objectively measured PA.