Page 46 - CASA Bulletin 2019 Vol 6 No 4

CASA Bulletin of Anesthesiology

DOI: 10.31480/2330-4871/093
been reported in the literature, more recent studies viewed had sources of potential funding or affilia-
have concluded that racial health disparities generally tion bias [8-14]. Four studies used Medtronic devices
exist as consequences of racism, rather than race itself and were simultaneously funded and/or managed by
[35-39]. In a 2009 review on racial disparities in pain, Medtronic [8-10,14]. Authors involved in the PROCESS

Anderson, et al. concludes that studies should control study were also receiving financial reimbursements

for variables such as discrimination, immigration, the from Medtronic for consultancy work [10,14]. Two au-
process of acculturation, health status, education, thors listed on the Schu, et al. paper received a research
occupation, income, neighborhood socioeconomic fellowship grant from, and served as consultants for, St.
level, and language of choice, among others [34]. Jude Medical - the device manufacturer for their study
Analyzing data from 13,777 patients, Reyes-Gibby, et al. [13]. Two authors for the Al-Kaisy [9] study received

found that significant predictors for racial differences sponsorship and speaker fees from Medtronic, while
in pain severity included chronic disease, psychosocial two different authors on the same study are Medtronic
distress, Medicaid insurance, and lower education level employees. Van Havenbergh’s study was not funded by
[40]. Thus, assessing a multitude of factors associated St. Jude Medical; however, one of the authors is a St.

with the nuanced consequences of racism in its various Jude employee [12]. Turner, et al.’s study was funded by
forms (internalized, interpersonal, institutional [41]) the Washington State Department of Labor and Indus-
rather than the imprecise and outdated categories of tries, which pays for Washington state workers’ com-
race would facilitate more accurate analyses of pain pensation insurance [11].
treatment outcomes. However, none of the studies Three studies denied or minimized any potential
included in this review provided subgroup analysis conflicts of interest [15,16,18]. De Andres specifically

regarding the impact of these variables on the success noted having independent funding sources with active
of SCS for FBSS. This remains a knowledge gap that is in minimization of the role of manufacturing representa-
need of further investigation.
tives in the study [15].
Limitations One studies did not disclose whether or not conflicts

Limitations for this systematic review include a low might have existed [17].
volume of studies available for review as well as the Conclusion
inability to consolidate data due to the heterogeneity
of quantitative analysis tools between studies. Individ- FBSS is now one of the most common indications
ual study limitations chiefly remain the inability to com- for the utilization of SCS. Evidence for the efficacy of
pare outcomes to a placebo group until the advent of SCS in this indication is accumulating, with most studies
more advanced delivery methods. Only 3 studies were demonstrating its efficacy - especially for those patients
of high quality as assessed by the Jadad scale [9,13,15]. with leg pain as the predominant symptom. However,
Further, the patient characteristics assessed were not a significant weakness in the current available data in-
exhaustive and there are additional patient character- cludes potential bias based on the funding source for
istics that can affect treatment outcomes that were not most studies. Additionally, it is clear that SCS provides
mentioned in this review (Table 2). short-term benefit, yet there is no solid evidence that
SCS provides any benefit beyond two years of implanta-
Study Bias tion. Another major concern of SCS is its significant pla-
Importantly, seven out of the eleven studies re- cebo effect, which makes the true therapeutic response

Table 2: Jadad Scale [7].
Jadad scale for reporting randomized controlled trials
Item Maximum points Description
Randomization 2 1 point if randomization is mentioned
1 additional point if the method of randomization is appropriate
Deduct 1 point if the method of randomization is inappropriate
(minimum 0)
Blinding 2 1 point if blinding is mentioned
1 additional point if the method of blinding is appropriate
Deduct 1 point if the method of blinding is inappropriate
(minimum 0)
An account of all patients 1 The fate of all patients in the trial is known. If there are no data
the reason is stated

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