PALM SPRINGS, Calif. — Smoking and obesity do not appear to interfere with the efficacy of spinal cord stimulators (SCS), nor do they appear to lead to risk of infection at the procedure site, according to research presented at the 32nd Annual Meeting of the American Academy of Pain Medicine (AAPM).
To examine the effects of smoking and obesity on SCS efficacy and the rates of common SCS complications, Nebojsa Knezevic, MD, PhD, from the Advocate Illinois Masonic Medical Center, and colleagues conducted a retrospective analysis of 64 patients who had received trial and permanent placement of SCS from January 2005 to July 2014 who were followed up for at least 1 year.
The researchers compared smokers and non-smokers, as well as different BMI groups (group 1-normal<24.9; group 2-overweight<29.9, and group 3-obese>30.0).
The investigators found that the average pain score did not differ between the groups: the average pain score before SCS placement was 7.6+1.2 for smokers and 7.6+1.8 for non-smokers (p=0.991). The average pain after SCS placement was 3.2+1.6 for smokers and 3.89+2.0 for non-smokers (p=0.242). Smokers were also not predisposed to infection (p=0.278). However, smokers were significantly likely to experience lead migration (p=0.006) and need for revision (p=0.001).
The reason for this outcome is unknown, Dr Knezevic told Clinical Pain Advisor in an interview. “One of the possibilities is that coughing, which is more frequent in smokers due to increased incidence of chronic obstructive pulmonary disease (COPD), might cause the lead migration and [subsequent] requirement for revision.”
Pain also did not differ depending on BMI: pain before SCS placement for group 1 was 8.3±1.9, group 2 was 7.1±1.2, and group 3 was 7.4±1.5 (p=0.092). The average pain 1 year after SCS implantation for group 1 was 3.9±2.1, group 2 was 3.9±1.9, and group 3 was 3.3±1.9 (p=0.516). They also did not observe statistical significance for risk of infection and complications with increasing BMI.
The researchers conclude that their preliminary study results demonstrate smoking and obesity do not interfere with the efficacy of SCS therapy, nor do they lead to increased risk of infection at the procedure site.
“We are planning to continue collecting data on our patients with the spinal cord stimulators,” Dr Knezevic said.
Knezevic N, Lissounov A, Knezevic I, Kenneth C. Abstract #133. Smoking and Obesity Do Not Interfere with Efficacy of Spinal Cord Stimulators and Do Not Increase the Risk of Complications. Presented at: AAPM 2016. February 18-21, 2016; Palm Springs, California.