Factors Predicting Quality of Life in Obese Patients after Bariatric Surgery

Abstract

Obesity is a global public health concern that leads to pathophysiological changes. These changes significantly impair mobility, hinder daily functioning, reduce sleep quality, and ultimately deteriorate an individual’s overall quality of life. Excessive accumulation of adipose tissue also in obese patients increases the risk of accidents, particularly motor vehicle accidents, which in turn impacts occupational performance and restricts job opportunities. As the prevalence of obesity continues to rise globally, effective treatment strategies have become increasingly crucial. Bariatric surgery has emerged as a standard and effective treatment modality for patients suffering from severe obesity, particularly those with a body mass index (BMI) ≥ 40 kg/m². This surgical intervention effectively reduces excess body weight and helps manage or even resolve obesity-related comorbidities. Moreover, it improves physical appearance, self-confidence, and quality of life. Key factors influencing postoperative quality of life include the percentage of excess weight loss (%EWL), depression, physical functioning, and social support.

This predictive correlational study was designed to examine the influence of selected variables on the quality of life among individuals who had undergone bariatric surgery. The conceptual framework was based on Wilson and Cleary’s model of health-related quality of life, which integrates biological and psychological aspects to offer a comprehensive view of factors influencing patient well-being. A purposive sampling approach was utilized to recruit participants who met specific inclusion criteria. Eligible participants were aged 18 years or older, of both sexes, had been clinically diagnosed with obesity, and had undergone either Laparoscopic Sleeve Gastrectomy or Roux-en-Y Gastric Bypass surgery at least six months before the study—individuals who were not diagnosed with cancer, kidney disease, heart failure, or stroke. Additionally, participants were required to have no impairments in vision, hearing, or other sensory functions. All participants were required to be fluent in Thai and willing to engage fully in the research process. Data collection involved the use of five well-established instruments. These included: a demographic and health information questionnaire; the Center for Epidemiologic Studies Depression Scale (CES-D), which measures depressive symptoms; the Karnofsky Performance Status Scale, used to assess physical functioning; the Social Support Questionnaire; and the Obesity and Weight-Loss Quality of Life Instrument. Descriptive statistics, including means and standard deviations, were used to summarize participant characteristics, while hierarchical regression analysis was employed to identify significant predictors of quality of life.

The results indicated that participants had a generally good quality of life (Mean = 53.30, SD = 26.17). The average %EWL was 58.42% (SD = 17.63), indicating a substantial reduction in excess body weight. In terms of mental health, participants, on average, did not report clinical levels of depressive symptoms, as reflected in the mean CES-D score of 11.40 (SD = 8.76). Social support was also reported to be good, with a mean score of 3.55 (SD = 0.54), suggesting that most individuals had access to supportive interpersonal relationships following surgery. Hierarchical regression analysis demonstrated that depression and physical functioning were statistically significant predictors of postoperative quality of life, jointly accounting for 25.40% of the variance in quality of life scores (R² = .25, F = 6.37, p < .001). Among these two factors, depression emerged as the most influential predictor (β = -0.38, p < .001), followed by physical functioning (β = 0.36, p = .002).

These findings have important implications for healthcare providers and policymakers involved in the postoperative care of bariatric patients. Interventions should prioritize regular screening and management of depression, as untreated psychological distress can significantly undermine the benefits of surgical weight loss. Additionally, programs aimed at promoting physical rehabilitation and functional independence can further enhance long-term outcomes. Emphasis should also be placed on reinforcing social support systems, as positive interpersonal interactions contribute to emotional resilience and encourage sustained lifestyle changes. Ultimately, maintaining weight loss, fostering self-worth, and promoting a positive body image are essential components in achieving a lasting improvement in quality of life after bariatric surgery.

Keywords: Bariatric surgery, Obese patients, Quality of life

Author’s contributions:

PK: Conceptualization, method and design, tool validation, data collection, data analysis, wrote manuscript, revised manuscript

SC: Conceptualization, method and design, data analysis, wrote manuscript, revised manuscript, edited manuscript, corresponding with editor-in-chief

PP: Conceptualization, method and design, data analysis, revised manuscript