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Frailty of older patients getting ambulatory general surgery correlates with risk of complications, according to a national study -- although defining frailty remains fraught, even for transcatheter procedures.

The National Surgical Quality Improvement Program (NSQIP) modified frailty index -- a tool validated across surgical specialties -- was tied to independently of age and other patient characteristics, reported Carolyn Seib, MD, MAS, of University of California San Francisco, and colleagues online in JAMA Surgery.

For example, an intermediate score in the 0.18-0.35 range was associated with 70% more complications of any kind compared with a lower index (2.7% versus 1.5%, adjusted OR 1.70, 95% CI 1.54-1.88) and twice as many serious complications (1.3% versus 0.6%, adjusted OR 2.00, 95% CI 1.72-2.34). A higher frailty score was associated with more than triple the incidence of overall complications (5.8% versus 1.5%, adjusted OR 3.35, 95% CI 2.42-4.46) and serious complications (3.0% versus 0.6%, adjusted OR 3.95, 95% CI 2.65-5.87).

"Surgeons should consider frailty rather than chronological age when counseling and selecting patients for elective ambulatory surgery," Seib's group said, emphasizing that the "goal for frailty assessment in the preoperative setting should be to improve patient selection and the informed consent process for frail patients, regardless of chronological age, and to remove barriers to treatment for older nonfrail patients."

Craig Smith, MD, of New York's Columbia University Medical Center, called the findings "entirely unsurprising and almost certainly accurate" in commenting to 乌鸦传媒, and added that "patients with multiple medical co-morbidities have more complications. What sells [the authors'] message is relabeling co-morbidities as 'frailty.'"

However, there is little agreement as to what constitutes reproducible and relevant measures of frailty, he said, and most measures that attempt to address functional abilities can't be assessed in the operating room and may be hard to obtain in older, disabled patients.

"Despite all the interest in 'frailty' as a predictive variable, I'm not sure we've gotten much better than knowing it when we see it, which we usually do," Smith said.

The assessment of frailty is "a moving target," he said, with consensus originally forming around a cluster of four functional measures (activities in daily living, handgrip, albumin, 5-minute walk) and more recently migrating to a focus on just the 5-minute walk.

Applicability to Transcatheter Procedures

Smith himself tried to pin down what frailty is in his work on the PARTNER 1 and PARTNER 2 trials on transcatheter aortic valve replacement (TAVR).

Frailty assessment of TAVR candidates is particularly challenging -- yet an important clinical consideration nonetheless, according to Danny Dvir, MD, of Seattle's University of Washington Medical Center.

"It is challenging to accurately define frailty and there are dozens of different frailty calculators out there. One of the issues is that some definitions were validated in specific patient cohorts. It is conceivable that frailty definition for a relatively young patient that is scheduled for elective hernia surgery will be different than a frailty definition for a patient scheduled for TAVR since the physiological reserve required differs between the two."

While the NSQIP frailty index used by Seib's group has been validated in several studies, it is not well-tested in the TAVR population, Dvir continued.

Hypothetically, however, a higher score would make could make someone "a much better candidate for TAVR than for traditional surgical aortic valve replacement," said Timothy Gardner, MD, of Christiana Care Health System in Newark, Delaware. "We routinely assess frailty as a procedural risk factor, especially in older or elderly patients who have severe aortic valve disease."

The study investigators defined frailty as "a measure of decreased physiological reserve that is associated with morbidity and mortality in major elective and emergency general surgery operations," which isn't a bad definition, according to Gardner. "Most frailty indices use the [same] medical or physical conditions that were used in this article to determine the degree of frailty," he commented.

The NSQIP Index

The 11 traits included in the NSQIP modified frailty index were:

• History of diabetes
• Impaired functional status
• History of chronic obstructive pulmonary disease or pneumonia
• History of congestive heart failure
• History of MI within 6 months
• History of percutaneous coronary intervention
• Cardiac surgery or angina
• Antihypertensive medication use
• Peripheral vascular disease or rest pain
• Impaired sensory faculties
• History of transient ischemic attack or cerebrovascular accident with persistent residual deficit

Study participants were those older than 40 years who underwent ambulatory hernia, breast, thyroid, or parathyroid surgery in 2007-2010 and were included in the American College of Surgeons NSQIP Participant Use File (n=140,828).

Anesthesia with local and monitored anesthesia the only modifiable variable found associated with lower 30-day rates of serious complications (adjusted OR 0.66, 95% CI 0.53-0.810), Seib and colleagues found.

They acknowledged that 30-days was a short period to assess post-surgical outcomes; that the NSQIP does not capture the full spectrum of potential events such as accelerated cognitive decline; and that large academic teaching institutions are overrepresented in the database, limiting its generalizability.

For now, frailty is a "spectrum," according to Dvir.

"Although too many previous studies reported patients as either frail or non-frail in a binaric fashion, many patients are in the gray zone. I hope that in the future patients would be characterized in frailty scales," he said. "I believe that the current study using a frailty scale would serve as a good introduction into that direction."

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