Quality of Life in Adults With Severe Obesity: A Systematic Review and Meta-Analysis of Cross-Sectional Studies.

PURPOSE: This systematic review aimed to synthesize evidence on the association between severe obesity (body mass index [BMI] ≥ 40 kg/m2) and quality of life (QoL) in adults who had not undergone bariatric surgery or other interventions specifically targeting QoL, and to identify the QoL domains in which lower scores were most consistently observed.

METHODS

Cohort and cross-sectional studies published up to March 2024 were eligible. The review protocol was registered in PROSPERO (CRD42023374612). PubMed, Embase, Scopus, Web of Science, SciELO, CINAHL, and LILACS were searched. Two independent reviewers selected studies, extracted data, and assessed methodological quality using the National Heart, Lung, and Blood Institute tool. Findings were synthesized narratively and through an exploratory random-effects meta-analysis of absolute SF-36 mean scores.

RESULTS

Twenty cross-sectional studies were included. The SF-36 and its variations were the most frequently used instruments. Across studies with BMI comparison groups, higher BMI categories were generally associated with lower QoL scores. The lowest scores were most consistently observed for physical functioning, role due to physical health, bodily pain, and general health. Among the mental health-related domains, vitality showed the most consistently reduced scores. Between-study heterogeneity was high for most pooled estimates.

CONCLUSION

Across the available cross-sectional evidence, adults with severe obesity generally had lower QoL, particularly in physical domains. However, substantial heterogeneity and the absence of longitudinal evidence limit certainty and preclude causal interpretation. Longitudinal studies using standardized QoL measures are needed.