Beyond the scale: health-related quality of life and weight loss in a 12-month digital lifestyle intervention

Introduction: Obesity is associated with reduced health-related quality of life (HRQoL). We examined the associations between HRQoL and weight loss in a 12-month real-world digital lifestyle intervention, the Healthy Weight Coaching (HWC) program. Methods: At baseline, participants self-reported their weight, height, and waist circumference, followed by weekly weight and quarterly waist tracking. HRQoL was assessed at baseline, 6 months, and 12 months using the RAND-36, which covers eight domains (physical functioning, role limitations due to physical health, bodily pain, general health, vitality, social functioning, role limitations due to emotional problems, and mental health) where higher scores indicate better HRQoL. Results: Data from 1848 participants (82.9% women, median age 52 years, median BMI 39.1 kg/m2) showed that higher baseline body mass index correlated with lower HRQoL in physical functioning, bodily pain, general health, and social functioning. Using K-means clustering, we identified three distinct clusters: High HRQoL, Physical health burden, and Globally low HRQoL. Lower baseline HRQoL in vitality, role limitations due to emotional problems, and mental health, as well as membership in the Globally low HRQoL cluster, predicted smaller weight loss. Participation in HWC was associated with improvements across all HRQoL domains. Each 5% weight loss corresponded to increases of 3.8 points in general health, 3.3 points in physical functioning, 2.3 points in vitality, 2.1 points in bodily pain, 1.2 points in social functioning, and 1 point in mental health. Participants who lost 5% of their weight experienced greater improvements in physical functioning and general health compared with those who lost <5%. Membership in the Globally low HRQoL cluster and below-median baseline scores in role limitations due to physical health, general health, and vitality predicted higher dropout rate. Conclusions: Digital lifestyle programs may improve both weight outcomes and the overall lived experience of individuals seeking weight management.