What is the effect of bariatric surgery on health-related quality of life in people with obesity? Observational cohort analysis of the United Kingdom National Bariatric Surgery Registry.

BACKGROUND

Previous small studies investigating health-related quality of life (HRQoL) following bariatric surgery have demonstrated heterogenous effects. This study aimed to use National Bariatric Surgery Registry (NBSR) records to investigate the relationship between weight and HRQoL in people undergoing bariatric surgery in the UK.

MATERIALS AND METHODS

In this observational study using United Kingdom National Bariatric Surgery Registry (NBSR) records between 1st June 2017 and 23rd November 2022, patients undergoing primary bariatric surgery with one baseline and at least one follow-up visit within 1 year from surgery were eligible for inclusion. Models estimated the relationship between EuroQol Five Dimension 5-level (EQ-5D) and BMI at baseline and longitudinally. Further analyses were stratified by type 2 diabetes, type of operation (adjustable gastric band, sleeve, or bypass), and domain of EQ-5D.

RESULTS

Five thousand five hundred eighty-seven observations of 2160 patients were analysed. At baseline, the mean BMI was 45.7±7.8 kg/m 2 and the mean EQ-5D was 0.78±0.22. A 1 kg/m 2 higher BMI was associated with 0.005 (95% CI [-0.006 to -0.004]) lower EQ-5D. In the month following surgery, EQ-5D increased to 0.91±0.2 while BMI decreased to 39.8±7.1 kg/m 2 ( P <0.001 for both); subsequently, EQ-5D plateaued (0.90±0.17 at 12 months) while BMI continued to decrease (31.5±6.2 kg/m 2 at 12 months, P <0.001). Each 1 kg/m 2 decrease in BMI was associated with a 0.006 (95% CI [-0.007 to -0.005]) increase in EQ-5D. Remission of T2D was independently associated with increase in EQ-5D (0.037, 95% CI [0.015-0.059]); type of operation was not. Decreases in BMI were associated with improvements in all five domains of EQ-5D.

CONCLUSIONS

In this large dataset, greater weight loss and T2D remission were independently associated with greater improvements in HRQoL following bariatric surgery. The HRQoL-BMI relationship for people undergoing bariatric surgery differs to that which has previously been estimated following behavioural interventions. The use of the estimates generated here will be important for clinical and political decision-making.