Weight Loss Surgery Called Riskier in Older Adults

DALLAS, Nov. 21 -- Weight loss surgery may be too risky for older patients, according to a population-based study of outcomes.

The postsurgical adverse event rate increased with age to more than 32.3% for patients 65 and older, compared with 8.0% for younger patients, reported Edward H. Livingston, M.D., of the University of Texas Southwestern Medical Center here, and a colleague, in the November Archives of Surgery.

Mortality for patients 65 and older was 3.2%, compared with 0.2% in younger patients without Medicare, in the analysis of the National Inpatient Survey, which contains discharge information for 20% of all U.S. hospitalizations.

"Given that the operations may not be as effective in elderly persons relative to young persons and that there are high adverse event and mortality rates for older patients," the authors wrote, "limiting bariatric procedures to those younger than 65 years may be appropriate."

Previous studies have had conflicting results. Some have shown increased complication and mortality rates for older patients and others have found bariatric surgery to be as safe and effective in older patients as it is in younger patients.

The researchers analyzed 25,428 bariatric procedures performed in 2001 and 2002 included in the National Inpatient Survey. They defined adverse outcomes as length of hospital stay exceeding the 95th percentile (seven days), discharge to a long-term care facility or in-hospital death during admission for the operation.

Overall, the patients were predominantly female (84.1%), middle age (median 41 with 0.8% being 65 and older) and not insured by Medicare (94%).

Because nearly all patients 65 and older had Medicare insurance (85.7%), they were considered as a single group. The median length of stay was three days.

In a logistic regression analysis, the researchers reported several independent risk factors for bariatric surgery mortality. They were:

• Age (odds ratio 1.04, 95% confidence interval 1.02 to 1.07),
• Male sex (OR 2.45, 95% CI 1.48 to 4.03),
• Electrolyte disorders (OR 13.91, 95% CI 8.29 to 23.33), and
• Congestive heart failure (OR 4.96, 95% CI 2.52 to 9.77).

Adverse outcomes increased as a function of age in a nearly linear fashion, with a steep increase after the age of 65. Older patients most frequently had gastrointestinal tract complications (30.6%). Unintentional intraoperative lacerations were "reasonably frequent," with an occurrence rate ranging from 10.2% to 15.8%.

Most Medicare patients undergoing these operations were younger than 65 and had a much greater disease burden than non-Medicare patients. They accounted for a higher adverse outcome (21.6%) and mortality (0.7%) compared with patients without Medicare (8.0% and 0.2%). When patients with similar comorbidities were compared, Medicare status alone did not affect outcomes.

Comparing complication rates found in the study with those of other studies is complicated, said the researchers. Prior series had no consistent definition for "older"-- ranging from 50s to 60s--and reported results for a variety of bariatric operations. In these series, mortality ranged from 0% to 8.0% for older patients.

They concluded that "further evaluation of the perioperative morbidity and mortality and long-term outcomes should be performed for this population."

In an invited critique of the study, Clifford W. Deveney, M.D., of the Oregon Health and Science University in Portland, said that although high-risk patients such as the elderly may face more dangers from surgery, they also stand to benefit the most from weight loss surgery/

"It is not certain when the risks outweigh the potential gains," he wrote. "We need to look at benefits in the vast majority of patients who survive their bariatric procedure to determine what is an appropriate risk for a given patient. These data will only come from prospective studies designed to assess long-term outcomes following bariatric procedures."

Dr. Deveney pointed out that the study has the limitations associated with retrospective data acquisition from large databases.

For example, he wrote, "all bariatric procedures were analyzed together (Roux-en-Y gastric bypass, biliopancreatic diversion with duodenal switch, lap band, and so forth), so we have no idea if these data apply to all procedures. Furthermore, the data are collected from all hospitals, not simply from those that have bariatric centers. Conspicuously absent from the data is an analysis of the effect of weight and body mass index on outcomes; perhaps these data were not obtainable from these databases."

He also pointed out that "these data combining Medicare patients and age correlate with and demonstrate that morbidity is related to comorbidities rather than simply to Medicare status. The irony is that these operations are the best and, in some instances, the only effective treatment for these comorbidities."