Long-Term Trajectories in Weight and Health Outcomes Following Multidisciplinary Publicly Funded Bariatric Surgery in Patients with Clinically Severe Obesity (≥ 3 Associated Comorbidities): A Nine-Year Prospective Cohort Study in Australia

Abstract

Background: Real-world data on long-term (> 5 years) weight loss and obesity-related complications after newer bariatric surgical procedures are currently limited. The aim of this longitudinal study was to examine the effectiveness and sustainability of bariatric surgery in a cohort with clinically severe obesity in a multidisciplinary publicly funded service in two teaching hospitals in New South Wales, Australia. Methods: Patients were adults with complex clinically severe obesity with a BMI ≥ 35 kg/m2 and at least three significant obesity-related comorbidities, who underwent bariatric surgeries between 2009 and 2017. Detailed obesity-related health outcomes were reported from annual clinical data and assessments for up to 9 years of follow-up. Data were also linked with the national joint replacement registry. Results: A total of 65 eligible patients were included (mean, 7; range, 3−12 significant obesity-related comorbidities); 53.8% female; age 54.2 ± 11.2 years, with baseline BMI 52.2 ± 12.5 kg/m2 and weight 149.2 ± 45.5 kg. Most underwent laparoscopic sleeve gastrectomy (80.0%), followed by laparoscopic adjustable gastric banding (10.8%) and one anastomosis gastric bypass (9.2%). Substantial weight loss was maintained over 9 years of follow-up (p < 0.001 versus baseline). Significant total weight loss (%TWL ± SE) was observed (13.2 ± 2.3%) following an initial 1-year preoperative intensive lifestyle intervention, and ranged from 26.5 ± 2.3% to 33.0 ± 2.0% between 1 and 8 years following surgery. Type 2 diabetes mellitus (T2DM), osteoarthritis-related joint pain and depression/severe anxiety were the most common metabolic, mechanical and mental health comorbidities, with a baseline prevalence of 81.5%, 75.4% and 55.4%, respectively. Clinically significant composite cumulative rates of remission and improvement occurred in T2DM (50.0−82.0%) and hypertension (73.7−82.9%) across 6 years. Dependence on continuous positive airway pressure treatment in patients with sleep-disordered breathing fell significantly from 63.1% to 41.2% in 6 years. Conclusion: Bariatric surgery using an intensive multidisciplinary approach led to significant long-term weight loss and improvement in obesity-related comorbidities among the population with clinically complex obesity. These findings have important implications in clinical care for the management of the highest severity of obesity and its medical consequences. Major challenges associated with successful outcomes of bariatric surgery in highly complex patients include improving mental health in the long run and reducing postoperative opioid use. Long-term follow-up with a higher volume of patients is needed in publicly funded bariatric surgery services to better monitor patient outcomes, enhance clinical data comparison between services, and improve multidisciplinary care delivery.

Keywords: bariatric surgery; clinically severe obesity; long-term outcomes; multidisciplinary management; publicly funded.

Figure 1

Modelled percentage total weight loss (%) from initial clinic visit (i.e., 1 year prior to surgery, with lifestyle modifications and medical consultations) to preoperation and year 8 post-bariatric surgery. The overall estimated marginal mean weight loss at each visit over time modelled from the mixed-effects model with random effects, taking into account the repeated measures nature of the data. Lines indicate modelled weight change from baseline based on mixed models adjusted for baseline factors (age at time of surgery, sex and race). A negative value represents weight loss based on pre-surgery weight. Data markers (estimated marginal mean values) indicate weight change data. Error bars represent the 95% CI.

Figure 2

Prevalence of obesity-related comorbidities preoperatively and at 1–6 years following bariatric surgery (%).

Figure 3

Yearly remission and improvement rates of T2DM, hypertension and hyperlipidaemia following bariatric surgery.

Figure 4

Prevalence of sleep-disordered breathing and CPAP/BiPAP prescription among the study population undergoing bariatric surgery.

Figure 5

Prevalence of prescribed opioids and incidence of TJA among patients with OA-related joint pain.

Figure 5

Prevalence of prescribed opioids and incidence of TJA among patients with OA-related joint pain.

Figure 6

Prevalence of depression/severe anxiety, as well as the use of antidepressants and/or antianxiety agents among the study population.