Bariatric surgery for the severely obese can dramatically improve long-term health, according to two observational studies.
Compared with usual obesity care, bariatric surgery was tied to a significant reduction in all-cause mortality over several years, reported Orna Reges, PhD, of the Clalit Research Institute in Tel Aviv, and colleagues.
There were 2.51 fewer deaths per 1,000 person-years (95% CI 1.86-3.15) in those who underwent laparoscopic banding, Roux-en-Y gastric bypass, or laparoscopic sleeve gastrectomy versus those receiving nonsurgical care (aHR for mortality 2.02, 95% CI 1.63-2.52), they wrote in the Journal of the American Medical Association as part of a theme issue on bariatric procedures. (Other studies covered effects on cardiovascular biomarkers and results from different types of procedures.)
During the median 4.3-year follow-up period, this resulted in 105 deaths reported among surgery patients versus 583 deaths among nonsurgical care patients.
When broken down by surgery type, the lowest rate of all-cause mortality during follow-up was reported among the sleeve gastrectomy group (26 deaths, 0.8%), followed by Roux-en-Y gastric bypass (18 deaths, 1.3%), and laparoscopic banding 61 deaths, 1.7%).
Patients receiving nonsurgical obesity care had a higher risk of all-cause mortality versus each surgery type:
- Sleeve gastrectomy: HR 1.60 (95% CI 1.02-2.51)
- Roux-en-Y gastric bypass: HR 2.65 (95% CI 1.55-4.52)
- Laparoscopic banding: HR 2.01 (95% CI 1.50-2.69)
Currently, the majority of available research on bariatric surgery has centered around short-term outcomes, the researchers wrote. “Additionally, most of the available long-term outcome data focuses on 1 of 2 outdated procedures: vertical band gastroplasty or laparoscopic banding, or gastric bypass,” they noted. “Recently, sleeve gastrectomy has become a very popular approach for surgically induced weight loss. Very little is known about the long-term outcomes for sleeve gastrectomy.”
The retrospective study included 8,385 individuals with a median BMI of 40.6 who had laparoscopic banding (n=3,635), gastric bypass (n=1,388), or laparoscopic sleeve gastrectomy (n=3,362). They were matched with 25,155 individuals with a median BMI of 40.5 who were provided “usual” obesity management medical care from primary care physicians, including diet counseling and behavioral support.
Characteristics were generally similar between the surgical and nonsurgical groups at baseline, with some of the most common comorbidities including diabetes (28.5% surgery versus 28.5% control), hyperlipidemia (52.9% versus 48.7%), and hypertension (44.4% versus 42.4%).
Nearly all of the secondary outcomes measured over the median 4.3-year follow-up significantly improved among the surgery patients compared with those who received nonsurgical care. This included diabetes remission, which was achieved by 23.6% of surgery patients — with the highest remission rates for the sleeve gastrectomy group (31.9%) — versus only 5.1% of all nonsurgical care patients.
Similarly, need for pharmaceutical treatments was significant lowered among surgery patients compared with nonsurgical care during the follow-up period:
However, rate of hospital admission during this period was higher for the surgery group (43.2% surgery versus 37.1% control), which was highest among the laparoscopic banding group (52%).
In another JAMA study, bariatric surgery was associated with significantly improved obesity-related comorbidities versus nonsurgical care:
- Diabetes remission: Relative risk 3.9 (95% CI 2.8-5.4)
- Hypertension remission: RR 2.1 (95% CI 2.0-2.2)
- Dyslipidemia remission: RR 2.6 (95% CI 2.4-2.8)
- New-onset hypertension: RR 0.4 (95% CI 0.3-0.5)
New-onset risk for diabetes and dyslipidemia were also significantly lowered among the surgery group compared with nonsurgical care (RR 0.07, 0.03-0.11 and RR 0.3, 0.2-0.4, respectively), according to Gunn Signe Jakobsen, MD, of the Morbid Obesity Centre at Vestfold Hospital Trust in Tønsberg, Norway, and colleagues.
However, individuals who underwent bariatric surgery also reported an increased risk for several other outcomes:
- New-onset depression: Relative risk 1.5 (95% CI 1.4-1.7)
- New-onset opioid use: RR 1.3 (95% CI 1.2-1.4)
- GI Surgery: RR 2.0 (95% CI 1.7-2.4)
- Anxiety/sleep disorder: RR 1.3 (95% CI 1.2-1.5)
A total of 1,888 people were included in the study and, among those, 932 underwent bariatric surgery and 956 received specialized, nonsurgical medical treatment. The vast majority of the surgery group underwent gastric bypass surgery (92%).
During the median 6.5-year follow-up, risk of complications requiring surgical procedures were more common after surgery versus usual care, including an operation for intestinal obstruction (RR 10.5 in surgery group, 95% CI 5.1-21.5). Although surgery patients tended to have slightly higher rates of anemia, hypocalcemia, and hypoalbuminemia 3 months after surgery, rates were not significantly different between the groups.
In an accompanying editorial, Edward H. Livingston, MD, of JAMA, highlighted two key differences in the studies’ findings. While the study by Jakobsen’s group found a significantly reduced need for hypertension and hyperlipidemia-related medication use after study, the study by Reges’ group reported no major reduction in hypertension and dyslipidemia medication use.
“Intuitively, this difference in results makes sense because hypertension is common in nonobese patients, and statins have other benefits in addition to treating dyslipidemia. It is unlikely that patients who have lost weight following bariatric surgery would be able to discontinue these medications,” he wrote.
“This finding suggests that the major health effects from bariatric surgery are related to inducing weight loss and controlling diabetes. The benefit of surgically induced weight loss on other outcomes, such as sleep apnea and osteoarthritis, were not addressed in these studies and more information is needed about how these complications of obesity might respond to bariatric surgery,” he stated.
Jakobsen disclosed funding from the Vestfold Hospital Trust.
Reges, Jakobsen, and co-authors, as well as Livingston, disclosed no relevant relationships with industry.
Robert Jasmer, MD Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, BSN, RN, Nurse Planner