Frailty has received much attention in the medical literature recently, and multiple spine surgery publications have reported that it is a risk factor for complications. Given that frailty indices take into account comorbidities, disability, and limited physiological reserve, this finding comes as no surprise. A more interesting question is whether or not frailty is modifiable. In order to better assess that question, Dr. Yagi and colleagues from Japan analyzed a prospectively collected database of 240 patients undergoing major surgery (average of 10 vertebral levels fused) for adult spinal deformity (ASD). Based on the medical record, they classified the patients as robust, prefail, or frail using the modified frailty index. As expected, the complication rate was higher for the frail groups. The novel aspect of this study is that the authors assessed how well the comorbidities contributing to frailty were under control. For example, in diabetic patients they determined if the hemoglobin A1C was less than 7% and, in hypertensive patients, they determined if blood pressure was less than 180/110. They classified patients whose comorbidities were being appropriately managed according to guidelines as those with good control of frailty, and those that were not being managed well as having poor control. The average age of their cohort was 58, and 92% were women. Fifty-nine percent were classified as robust, 34% prefrail, and 7% frail. After combining the prefrail and frail patients, they found that 72% had good control, and 28% had poor control of frailty. The prefrail and frail patients had worse baseline and two-year sagittal imbalance and SRS-22 scores. These patients also had a higher rate of complications. When comparing outcomes between patients with good and poor control of frailty, there were no significant differences in radiographic outcomes, SRS-22 scores, or complication rates. The poor control patients had a 26% increase in the odds of a complication compared to the good control group, though this was not statistically significant. The authors concluded that good control of frailty did not improve outcomes.
The authors have addressed a novel question and concluded that frailty is not a modifiable risk factor. Before accepting this conclusion, the study limitations need to be considered. For one, the number of poorly controlled patients is relatively low (n=27), and it is likely that the study was somewhat underpowered to detect differences between the good and poor control groups (for example, a 26% increase in the odds of a complication in the poor control group was not significant). Additionally, the authors did not assess whether or not efforts were actually made to treat the comorbidity, just whether or not the comorbidity was being controlled sufficiently according to guidelines. It is possible that patients with borderline diabetes were classified as having good control even though they just had mild disease, while some patients with brittle disease who were being treated aggressively were simply unable to meet the guidelines for being considered controlled. To truly answer the question about whether or not frailty is modifiable, patients would have to be randomized to an aggressive program to treat frailty pre-operatively vs. usual care. The current study supports the prior literature that shows frailty is associated with worse outcomes. While it raises the question of whether or not frailty is modifiable, I do not think it offers sufficient evidence for us to give up our efforts to optimize our patients pre-operatively.
Please read Dr. Yagi's paper on this topic in the May 15 issue. Does this change how you view the role of frailty in surgical decision making? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor