Bariatric Surgery versus Medical Management Effect on Health-Related Quality of Life in Adults with Severe Obesity and Type 2 Diabetes: A Prospective Cohort Study.

BACKGROUND

Obesity and type 2 diabetes mellitus (T2DM) represent major public health challenges in Saudi Arabia. While bariatric surgery is known to improve metabolic outcomes, comparative real-world evidence examining longitudinal health-related quality of life (HRQoL) outcomes relative to non-surgical medical management remains limited, particularly within Saudi clinical settings.

METHODS

This prospective observational cohort study compared adults with severe obesity and T2DM undergoing bariatric surgery with those receiving medical management over a 12-month follow-up period. A total of 190 participants were included (95 surgical; 95 medical), recruited consecutively from a tertiary care center. HRQoL was assessed at baseline, 6 months, and 12 months using the validated Arabic version of the WHOQOL-BREF. Medical management comprised lifestyle counseling and guideline-directed pharmacotherapy for diabetes and weight management. Longitudinal changes were analyzed using linear mixed-effects models incorporating fixed effects for group, time, and group-by-time interaction, with adjustment for baseline values and prespecified confounders.

RESULTS

Baseline HRQoL scores were comparable between groups across all domains (p > 0.05). Over 12 months, bariatric surgery was associated with greater improvements in all WHOQOL-BREF domains compared with medical management. Adjusted between-group differences at 12 months favored surgery for Physical Health (+ 10.01 points), Psychological Health (+ 7.62 points), Social Relationships (+ 8.25 points), Environment (+ 7.37 points), and Overall Quality of Life (+ 8.31 points) (all p < 0.001). Significant group-by-time interactions indicated divergent HRQoL trajectories between groups. Improvements in cardiometabolic parameters, including HbA1c and BMI, were also more pronounced in the surgical group. Effect sizes were large for Overall Quality of Life and Physical Health, though findings reflect associations rather than causal effects.

CONCLUSION

In this prospective observational cohort, bariatric surgery was associated with greater 12-month improvements in health-related quality of life and cardiometabolic outcomes compared with medical management among adults with severe obesity and T2DM. These results demonstrate longitudinal differences in patient-reported outcomes between treatment strategies but should be interpreted within the limitations of a non-randomized design.