The prevalence of undiagnosed pre-surgical cognitive impairment and its post-surgical clinical impact in elderly patients undergoing surgery for adult spinal deformity

Abstract

Background: Pre-existing cognitive impairment (CI) is emerging as a predictor of poor post-operative outcomes in elderly patients. Little is known about impaired preoperative cognition and outcomes after elective spine surgery in this patient population. The purpose of this study was to assess the prevalence of neuro CI in elderly patients undergoing deformity surgery and its impact on postoperative outcomes.Methods: Elderly subjects undergoing elective spinal surgery for correction of adult degenerative scoliosis were enrolled in this study. Pre-operative baseline cognition was assessed using the Saint Louis Mental Status (SLUMS) test. SLUMS consists of 11 questions, which can give a maximum of 30 points. Mild CI was defined as a SLUMS score between 21-26 points, while severe CI was defined as a SLUMS score of ≤20 points. Normal cognition was defined as a SLUMS score of ≥27 points. Complication rates, duration of hospital stay, and 30-day readmission rates were compared between patients with and without baseline CI.Results: Eighty-two subjects were included in this study, with mean age of 73.26±6.08 years. Fiftyseven patients (70%) had impaired cognition at baseline. The impaired cognition group had the following outcomes: increased incidence of one or more postoperative complications (39% vs. 20%), higher incidence of delirium (20% vs. 8%), and higher rate of discharge institutionalization at skilled nursing or acute rehab facilities (54% vs. 30%). The length of hospital stay and 30-day hospital readmission rates were similar between both cohorts (5.33 vs. 5.48 days and 12.28% vs. 12%, respectively).Conclusions: CI is highly prevalent in elderly patients undergoing surgery for adult degenerative scoliosis. Impaired cognition before surgery was associated with higher rates of post-operative delirium, complications, and discharge institutionalization. CI assessments should be considered in the pre-operative evaluations of elderly patients prior to surgery.

Current Perspectives on Postoperative Cognitive Dysfunction in the Ageing Population

“…Preoperatively, some established POCD risk factors are similar to those of mild cognitive impairment (MCI), and they include diabetes, poor glycaemic control and low cognitive reserve (12)(13)(14). Other MCI risk factors such as obesity, sleep fragmentation and APOE4 homozygosity have shown to have weaker risk associations with POCD (15)(16)(17).…”

Neuropsychological Functioning in Older Adults with Obesity: Implications for Bariatric Surgery

“…Pre-surgical cognitive functioning has been of increasing interest as a factor in predicting adverse surgical outcomes. Pre-surgical cognitive dysfunction in older adults has been associated with higher rates of non-bariatric surgery post-operative delirium [19][20][21] and cognitive decline 22 , longer hospital stay 20 , and reduced likelihood of being discharged to home 19,20,23 . Determining whether older adults with obesity are at greater risk for cognitive dysfunction has important implications for bariatric surgery, such as informing pre-surgical screening and planning for postoperative care needs.…”

Cognitive impairment is associated with greater preoperative symptoms, worse health-related quality of life, and reduced likelihood of recovery after cervical and lumbar spine surgery

“…Although patients undergoing surgical procedures to alleviate cervical and lumbar spine pain and restore function can experience major complications, the use of preoperative assessment and optimization tools has improved outcomes dramatically [1] , [2] , [3] . Cognitive impairment is a common, although underdiagnosed, condition in the United States and is not routinely included in preoperative screening or addressed as part of preoperative optimization [4] , [5] , [6] , [7] , [8] . However, cognitive function is one of the most important preoperative risk factors related to clinical outcomes, particularly in geriatric patients [9] , [10] , [11] .…”

“…As the U.S. population ages, focus on the influence of cognitive impairment on postoperative outcomes after spine surgery has increased [12] , [13] . The reported prevalence of preoperative cognitive impairment in elderly patients undergoing spine surgery is up to 70% [4] , [5] .…”

“…Preoperative cognitive impairment is the most important risk factor for the development of postoperative cognitive dysfunction, which affects nearly 1 in 4 patients who undergo spine surgery [5] . Furthermore, cognitive impairment has emerged as a risk factor for medical complications, prolonged hospital stay, and death [4] , [14] , [15] . Among patients undergoing adult spine deformity correction, those with cognitive impairment have been shown to have a higher incidence of postoperative complications (39%) compared to those without cognitive impairment (20%); the incidence of delirium was also higher in those with cognitive impairment (20%) than in those without (8%) [4] .…”