NASS News: Study Finds Tobacco Use Impacts Spinal Surgery Recovery

According to a new study presented at the 31st Annual Meeting of the North American Spine Society (NASS), tobacco use may harm the body’s healing response from a common spine surgery based on the number of cigarettes smoked over a lifetime.

“While it is well-established that smoking compromises healing from spine surgery, this new study suggests that improvement is actually tobacco dose-dependent,” said Alan S. Hilibrand, M.D., an orthopedic surgeon and 2016 Annual Meeting program chair. “This study gives spine specialists important data to help them counsel patients to quit smoking as early as possible.”

The study, “The Effect of Smoking on Spinal Cord Healing Following Surgical Treatment for Cervical Myelopathy,” was selected as one of the “best papers” at the NASS meeting. Cervical myelopathy is a common, progressive condition that generally impacts older people, with symptoms ranging from clumsiness with hand movements such as buttoning clothes, to an unsteady walk that can result in falls.

In the study, one surgeon’s 212 consecutive patients with cervical spondylotic myelopathy were categorized into two groups according to smoking status and stratified according to “pack years” and packs smoked daily. A pack year is defined as 20 cigarettes smoked every day for one year. Each patient was assessed and given a pre- and postoperative Nurick scale rating, which grades a patient’s difficulty in walking, from 0 to 5 (with 5 being the most severe).

Analysis was performed using simple linear regression and multiple regression controlling for age at presentation, sex, preoperative and postoperative Nurick score, duration of symptoms preoperatively, duration of follow-up, procedure performed, surgical approach, number of levels fused, diabetes status, cocaine use, ethanol use, preoperative magnetic resonance imaging signal change, and whether the patient belonged to the Veterans Administration.

Smoking status was not associated with a particular preoperative Nurick score. Univariate analysis demonstrated an impressive postoperative improvement in nonsmokers of 1.53 points on the Nurick scale, compared with just 0.6 points in smokers (p<.001). However, there was a progressive decrease in improvement as the number of pack years and packs per day increased (p<.001). There was a greater improvement in Nurick score with greater (worse) preoperative score but only in patients with fewer than 25 pack years.

“We found that tobacco use was directly correlated with decreased postoperative improvement in Nurick score,” said David Kusin, M.D., of the University of Nebraska Medical Center in Omaha. “Specifically, the mean improvement in Nurick score was almost one point lower in smokers than in nonsmokers.”

Smoking history was not associated with a more severe preoperative condition, he said, which suggests that smoking may interfere with the intrinsic healing processes that occur in the spinal cord postoperatively, but may not be an important etiology of cervical myelopathy.

“These data suggest that patients with cervical myelopathy who smoke are likely to have less improvement in their condition postoperatively, compared to those who do not smoke, and that the effect of each cigarette is additive,” Kusin noted. “These findings reinforce the importance of counseling patients about smoking cessation prior to surgery.”

The authors of the study are Kusin and Nicholas U. Ahn, M.D., from the Department of Orthopedic Surgery, University Hospital of Cleveland in Cleveland, Ohio. The abstract does not discuss or include any applicable devices or drugs.

The North American Spine Society is a multidisciplinary medical organization dedicated to fostering the highest quality, evidence-based and ethical spine care by promoting education, research, and advocacy. NASS is comprised of more than 8,000 members from several disciplines, including orthopedic surgery, neurosurgery, physiatry, neurology, radiology, anesthesiology, research, and physical therapy.