Joint replacement patients who improve their lifestyle and maintain a positive mindset before surgery are more likely to have better functional outcomes than those who do not, according to research presented at the 2011 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS). Multiple studies found that patients who smoke, misuse alcohol, fail to control blood sugar levels or simply have a poor attitude prior to undergoing total hip or knee replacement (THR/TKR) surgery can, in some cases, double their odds of post-operative complications.
Data were presented in three separate studies and one instructional course by researchers from Stanford University, the University of Alabama, the Orthopedic Institute in Miami and the University of Massachusetts.
"Some known risk factors for complications like advanced age and pre-existing heart or lung conditions are difficult or impossible to modify prior to surgery," said Jasvinder Singh, MD, associate professor of medicine at the University of Alabama in Birmingham. "In contrast, smoking, alcohol abuse, blood sugar levels and mental attitude are completely manageable by the patients themselves, which makes them an excellent target for prevention and intervention programs that are likely to improve outcomes."
The study found that current smokers had 41 percent higher odds of site infections (SSI) than those who had never smoked before. Current smokers also had significantly higher odds of pneumonia (53 percent,) stroke (161 percent) and one-year mortality (63 percent,) compared to never smokers.
Prior smokers were at higher odds of stroke (114 percent), pneumonia (34 percent), urinary tract infection (26 percent) and pulmonary complications (30 percent), compared with never smokers.
They analyzed data from 33,336 patients from the VA Surgical Quality Improvement Program (VASQIP) who underwent elective primary joint replacement procedures between October 2001 and September 2008. Specifically, they measured the association of smoking status at the time of surgery with 30-day, 90-day and one-year post-operative complication rates including surgical site and other infections, such as pneumonia, stroke, heart attack, and mortality.
Patients were on average 64 years old, mostly male (95 percent) and Caucasian (66 percent). Fifty-seven percent never smoked, 19 percent were prior smokers (who had stopped smoking at least a year before surgery) and 24 percent were current smokers.
"Since the risk of complications in joint replacement patients who smoke is quite significant and since it is possible that even short-term cessation may provide significant protection from such complications, it would be reasonable to approach surgical candidates for a pre-operative smoking-cessation program," said Dr. Singh. "If smokers are looking for a reason to quit, the waiting period before total joint replacement provides a golden opportunity."
Alcohol misuse a factor in likely complications (Embargo: February 15)In the first study, researchers from Stanford University evaluated post-surgical complication rates among 185 veterans who underwent total joint replacement surgery and who had admitted consuming alcohol in the past year based on their responses to the Alcohol Use Disorders Identification Test (AUDIT-C), a standardized annual assessment conducted at VA facilities.
They found that patients who reported the highest amount of alcohol consumption (at the level considered "alcohol misuse" *) were most likely to experience complications. In fact, each additional point in the 12-point scale corresponded with a 29-percent increase in the expected number of complications.
"Complications following total joint replacement and alcohol misuse are exponentially related," said lead author Nicholas J. Giori, MD, orthopaedic surgeon at Palo Alto Veterans Affairs Medical Center and associate professor of orthopaedic surgery at Stanford University Hospital. "These results, though from a small selection of patients, indicate the need for preoperative screenings and possibly interventions for alcohol misuse among joint replacement candidates."*The U.S. Health and Human Services offers a guideline for moderate alcohol use as one or fewer drinks per day for women and two or fewer drinks per day for men. This study defined "alcohol misuse" by the AUDIT-C a Veterans' Affairs screening tool.Patients at risk for "alcohol misuse" was defined by the AUDIT-C Veterans' Affairs screening tool and can include either drinking more than 4 times a week, having more than 9 standard drinks in a typical day, or routinely having more than 6 drinks a day.
In another study, researchers at the Orthopedic Institute in Miami reported that type 2 diabetic patients who had preoperative hypoglycemia (low blood sugar) and hyperglycemia (high blood sugar) fared worse after total joint replacement surgery than those who were able to keep their blood sugar (HbA1c) at normal levels.
Surgeons conducted 121 consecutive primary total joint replacements on type 2 diabetic patients and evaluated them based on preoperative HbA1c levels.* They divided the group into three segments—25 percent of patients were hypoglycemic, 50 percent were within normal ranges and 25 percent were hyperglycemic—and compared each of the three segment's patient-oriented outcomes, complications, length of stay and hospital costs.
Researchers found a significant trend toward worse scores in all categories among patients in the lowest and highest ranges.
"When set in a graph, the results looked like an inverted bell, with complications spiking on both ends of the spectrum and dipping in the middle," said Carlos J. Lavernia, MD, Chief of Orthopaedics at Mercy Hospital in Miami and Chief of the Orthopedic Institute. "Even after controlling for all external factors that could have affected the outcomes, the inverted-bell shape remained intact, indicating that diabetic patients who control their blood sugar prior to surgery will inevitably have better outcomes."*Many individual factors (including timing of last meal) are examined to determine a "normal blood glucose level," but medical expertise states that 70mg/dL- 120mg/dL is considered ideal. Patients with diabetes or hypoglycemia are urged to narrow that range even further and have or should have their own "norms" identified by a physician.
Finally, during a symposium moderated by David C. Ayers, MD, The Arthur Pappas Professor and Chair of Orthopedics at the University of Massachusetts Medical School, participants learned that patients can help to determine how well they tolerate the recovery process and the degree of functional improvement they gain after surgery based on their mental approach before, during and after surgery.
Dr. David C. Ring, MD, Associate Professor of Orthopaedic Surgery at Harvard Medical School and one of the symposium presenters, said, "Individuals who recognize within themselves the ability to ensure that things will be okay consistently report less pain and disability for a given disease or impairment."
Through a grant from the National Institutes of Health (NIH), Dr. Ayers is currently leading a team of researchers who are studying the emotional aspects of musculoskeletal health in patients undergoing total knee arthroplasty.
"There is a range of functional improvement patients experience after TKR. We have shown that patients with poor emotional health pre-operatively, that have poor coping skills, little social support, and are anxious, are at risk for less functional improvement after total knee replacement. We are studying the effect of placing these high-risk patients in a post-op pathway that directly addresses the factors in order to improve their functional improvement after TKR ," said Dr. Ayers. "In addition to offering top-notch surgical and medical care, all medical professionals should encourage patients to engage in positive lifestyle changes before and after surgery. The results will speak for themselves."