Tobacco use is not associated with a statistically significant increased risk of adverse events within 90 days in patients undergoing spinal fusion surgery, a new systematic review and meta-analysis, published in the Global Spine Journal by Ravi Nunna (University of Missouri, Columbia, USA) et al, has shown.
However, despite these findings, Nunna et al note that the “results are limited by the variable reporting methodology for both complication rates as well as smoking incidence between the included individual studies”.
Databases were queried to identify cohort studies that directly compared smokers with non-smokers and provided the absolute number of adverse events and the population at risk. Data quality was evaluated using the Quality in Prognosis Studies tool. Risk ratios (RR) and 95% confidence intervals (CIs) were calculated and compared between studies. The grading of recommendation, assessment, development and evaluation (GRADE) criteria were used to assess the strength of the evidence.
A total of 17 studies assessing 37,897 participants met the inclusion criteria. Of these, 10,031 (26.5%) were smokers and 27,866 (73.5%) were non-smokers. The mean age of the study population was 58 years and 45% were males.
The meta-analysis found that smoking was not associated with increased risk of one or more major adverse events within 90 days following spine surgery (seven studies, pooled RR 1.13, 95% CI [0.75–1.71], I2 = 41%).
However, smoking was significantly associated with one or more major adverse events in ≤ two level fusion (three studies, pooled RR 2.46, 95% CI [1.18–5.12], I2 = 0%), but not in fusions of ≥ three levels (four studies, pooled RR 0.87, 95% CI [0.70–1.08], I2 = 0%). Additionally, there was no statistically significant association between smoking and any adverse event, nor increased reoperation risk due to adverse events.