Most recent update: Tuesday, February 25, 2020 - 11:20

Bariatric News - Cookies & privacy policy

You are here

Post-op weight regain

Post-bariatric surgery weight regain may be population-specific

A multivariate analysis revealed that the type of surgery‚ the lack of a full time job and a previous abdominal surgery persisted as negative predictors for a successful bariatric surgery

Approximately 20% of bariatric surgery patients will regain weight after two years and, according to researchers from Mexico, the factors influencing regain are still controversial but may be population-specific. They stress that early detection of the patients that are more likely to fail is imperative to establish additional therapeutic strategies, without denying them the opportunity of surgery or waiting for weight re-gain to occur.

The paper, ‘Are there really any predictive factors for a successful weight loss after bariatric surgery?’, published in BMC Endocrine Disorders, sought to determine the proportion of patients that did not reach the goal of an excess weight loss of 50% or more during the first 12 months and determine the factors associated to this failure.

The researchers obtained the demographic, anthropometric and biochemical information from 130 patients with severe obesity who underwent bariatric surgery between 2012 and 2017. Unsuccessful weight loss was considered when the patient lost < 50% or more of the excess weight 12 months after surgery. They then compared the characteristics between the successful and unsuccessful groups in order to find the factors associated with success. The average age of the patients was 48 ± 9 years, 106 (81.5%) were women, 52% had a level of education of nine years or more (equivalent to high school), 67% were married or living with a partner, 35% did not have full time job.

Thirty-one percent of patients had elevated fasting plasma glucose and 26% were diagnosed with diabetes mellitus. Hypertension was present in 57% of them, dyslipidaemia in 29%, a previous cardiovascular event in 5% and history of deep venous thrombosis in 2%. Sleep apnoea had been diagnosed in 27% while 21% had been treated for osteoarthrosis at some point. A history of depression or anxiety diagnosed by a mental health specialist was present in 14% of the patients.

The median BMI at first evaluation was 48 (44–52), 40% had a BMI>50, with 36.1% of them having super obesity and 3.9% super-super obesity. The EBW% loss with diet and exercise interventions before surgery was 7% (0–12%), only 35% of the patients lost more than 10% of the excess weight before the surgery. Roux-en-Y bypass (RYGB) was performed in 38% of the patients, laparoscopic one anastomosis gastric bypass (OAGB) performed in 49% and gastric sleeve in the remaining 13%.


One year after surgery, 104 (80%) had loss 50% or more of the EBW and patients with a successful surgery were younger than the patients in non-successful surgery group (46±9 vs 52±8, p=0.005), had a lower frequency of hypertension (52% vs 77%, p=0.02), abdominal surgeries (46% vs 69%, p=0.03), depression or anxiety (11% vs 27%, p=0.03). They also had a lower number of obesity-related comorbidities (3 vs 2, p=0.02) and a higher proportion of patients lacking a fulltime job (53% vs 33%, p=0.05). The surgery most likely to end in a successful outcome at this time point was OAGB, while the less successful was the gastric sleeve (57% vs 9%, p=0.001).

The authors reported a significant inverse correlation between the baseline BMI and the %EBW lost at 12 months (p<0.001), meaning that the patients with Grade II obesity were likely to lose most of the EBW, patients in grade 3 obesity had a %EBWL of 63.7%, patients with super obesity lost 63.5% EBW while the super super obese patients lost between only 57% of EBW during the first year. However, absolute kg loss was similar between groups (grade II obesity patients lost on average 46kg during the first year, while the patients with super super obesity lost a mean of 54kg, p=0.076). These patients were also similar in terms of the presence of comorbidities and overall characteristics.

Figure 1: Weight variation (kg) before and after surgery of successful and non-successful groups

A comparison of patients with a successful versus non successful surgery at 12 months revealed that  there was no significant difference between their initial BMIs, the % EBW loss before surgery (Figure 1), the amount of exercise or calories registered or the content of the diet after surgery (carbohydrates, lipids and proteins). A multivariate analysis including age, hypertension, presence of a previous abdominal surgery, personal history of anxiety/depression disorder, lack of a full time job revealed that the type of surgery‚ the lack of a full time job and a previous abdominal surgery persisted as negative predictors for a successful bariatric surgery.

“Almost 20% of the patients that undergo bariatric surgery will not lose more than 50% of the EBW during the first 12 months. Some of these patients will probably also fail to reach that goal in the subsequent years,” the authors concluded. “The factors influencing that result are still controversial but may be population-specific and worth evaluating in order to establish the best diagnostic, therapeutic and follow-up strategy for every particular centre.”

To access this paper, please click here

Want more stories like this? Subscribe to Bariatric News!

Bariatric News
Keep up to date! Get the latest news in your inbox. NOTE: Bariatric News WILL NOT pass on your details to 3rd parties. However, you may receive ‘marketing emails’ sent by us on behalf of 3rd parties.