Mortality after lumbar fusion surgery.
METHODS
Retrospective population-based cohort study.


OBJECTIVE
To describe mortality after lumbar fusion surgery in Washington State workers' compensation claimants in the perioperative period and beyond.


BACKGROUND
Although lumbar fusion surgery can be associated with serious complications, perioperative mortality is generally considered rare. Population-based mortality estimates have been limited to surgery in older adults.


METHODS
We identified all Washington State workers' compensation claimants who underwent fusion between January 1994 and December 2001 (n = 2378) and assessed the frequency, timing, and causes of death. Mortality follow-up was concluded in 2004. Death was ascertained from Washington State vital statistics records and from the workers' compensation claims database. Poisson regression was used to obtain age- and gender-adjusted mortality rates. Years of potential life lost, percent of potential life lost, and mean potential life lost were calculated for the leading 5 causes of death and we calculated the risk of death associated with selected predictors.


RESULTS
Among the 2378 lumbar fusion subjects in the study cohort, 103 were deceased by 2004. The 3-year cumulative mortality rate was 1.93% (95% confidence interval, 1.41%-2.57%). The 90-day perioperative mortality rate was 0.29% (95% confidence interval, 0.11%-0.60%). The risk of perioperative mortality was positively associated with repeat fusions. The age- and gender-adjusted all-cause mortality rate was 3.1 deaths per 1000 worker-years (95% confidence interval, 0.9-9.8). Analgesic-related deaths were responsible for 21% of all deaths and 31.4% of all potential life lost. The risk of analgesic-related death was higher among workers who received instrumentation or intervertebral cage devices compared with recipients of bone-only fusions (1.1% vs. 0.0%; P = 0.03) and among workers with degenerative disc disease (age- and gender-adjusted mortality rate ratio, 2.71) (95% confidence interval, 1.17-6.28). The burden was especially high among subjects between 45 and 54 years old with degenerative disc disease (rate ratio, 7.45).


CONCLUSIONS
Analgesic-related deaths are responsible for more deaths and more potential life lost among workers who underwent lumbar fusion than any other cause. Risk of analgesic-related death was especially high among young and middle-aged workers with degenerative disc disease.
Juratli
Sham Maghout
SM
Division of Occupational and Environmental Medicine, Wayne State University School of Medicine, Detroit, MI, USA. shamj@u.washington.edu
Mirza
Sohail K
SK
Fulton-Kehoe
Deborah
D
Wickizer
Thomas M
TM
Franklin
Gary M
GM
D000328:Adult; D017677:Age Distribution; D000368:Aged; D000700:Analgesics / Q000009:adverse effects* / Q000627:therapeutic use; D015331:Cohort Studies; D055111:Failed Back Surgery Syndrome / Q000188:drug therapy / Q000453:epidemiology; D005260:Female; D006801:Humans; D016268:Internal Fixators / Q000009:adverse effects; D007405:Intervertebral Disc Displacement / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009026:Mortality; D010149:Postoperative Pain / Q000188:drug therapy* / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology; D012189:Retrospective Studies; D017678:Sex Distribution; D013123:Spinal Fusion / Q000401:mortality*; D014861:Washington / Q000453:epidemiology; D014942:Workers' Compensation
D000700:Analgesics