Is Spinal Surgery Safe for Elderly Patients Aged 80 and Above? Predictors of Mortality and Morbidity in an Asian Population

Neurospine Neurospine 2019;16(4):764-769. https://doi.org/10.14245/ns.1836336.168 Original Article Corresponding Author Jacob Yoong-Leong Oh https://orcid.org/0000-0002-2832-8433 Department of Orthopaedic Surgery, Spine Division, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433 Tel: +65-6257-7000 Fax: +65-6357-7715 E-mail: Received: December 30, 2018 Revised: February 9, 2019 Accepted: February 25, 2019 See Commentary “Spine Surgeons Are Facing the Great Challenge of Contributing to the Realization of a Society of Health and Longevity” via https://doi.org/10.14245/ns.19edi.019. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Copyright © 2019 by the Korean Spinal Neurosurgery Society pISSN 2586-6583 eISSN 2586-6591 Is Spinal Surgery Safe for Elderly Patients Aged 80 and Above? Predictors of Mortality and Morbidity in an Asian Population Joshua Yuan-Wang Tan1, Arun-Kumar Kaliya-Perumal1,2, Jacob Yoong-Leong Oh1 Spine Division, Department of Orthopaedic Surgery, Tan Tock Seng Hospital, Singapore Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 1 2 Objective: We aimed to determine the 2-year mortality and morbidity rates following spine surgery in elderly patients (age ≥ 80 years) and to study the associated risk factors. Methods: The records of patients ≥ 80 years of age who underwent spine surgery during the years 2003–2015 at Tan Tock Seng Hospital, Singapore were retrospectively reviewed. Information was collected on their demographic characteristics, comorbidities, diagnosis, general and neurological status, type of surgery, and outcomes. The mortality and morbidity rates over a 2-year period were analyzed. Bivariate analyses were carried out to identify factors associated with mortality. Results: We selected 47 patients (mean age, 83.3 years; range, 80–91 years) who were followed up for a mean duration of 27.7 months. The mortality rates at 30 days, 6 months, 1 year, and 2 years following surgery were 2.1%, 8.5%, 10.6%, and 12.8%, respectively. The factors significantly associated with mortality included multiple comorbidities, nondegenerative aetiology, and vertebral fractures. The overall morbidity rate was 48.9%, and 17% of this cohort had major complications. Conclusion: Surgeons should strategize management protocols with due consideration of the mortality and morbidity rates, and be wary of operating on patients with multiple comorbidities, nondegenerative conditions, and vertebral fractures. Keywords: 80 and over aged, Morbidity, Mortality, Risk factors, Spine INTRODUCTION Age is a known risk factor for increased mortality and poor outcomes following surgery.1-6 The presence of multiple comorbidities and reduced functional reserves are common among the elderly which can complicate management.5 There is some reluctance amongst spine surgeons to operate on elderly patients due to these perceived risks. Over the past 10 years, geriatric patient populations have increased and the average lifespan of Asian patients is amongst the longest in the world (Korea, Japan, Singapore, Hong Kong), with citizens living well into their eighties.7 Along with this increased life expectancy, spine surgeons will inevitably find themselves operating on older patients.8,9 764 www.e-neurospine.org Knowledge on the mortality rate among local elderly patients following spine surgeries and the risk factors associated with it can better guide treatment. To the best of our knowledge, only a few have reported the mortality outcomes in the Asian elderly population undergoing spine surgery. Therefore, we aim to address the following key questions, (1) What is the mortality rate amongst patients ≥ 80 years of age undergoing spine surgery? (2) What is the morbidity rate amongst patients ≥ 80 years of age undergoing spine surgery? (3) What are the risk factors associated with mortality? (4) Do comorbidities, nature and length of surgery influence mortality? Tan JYW, et al. Spine Surgery in the Elderly MATERIALS AND METHODS Table 1. Patient demographics (n = 47) Demographic Records of elderly patients ≥ 80 years of age who underwent spine surgery during the years 2003–2015 at Tan Tock Seng Hospital, Singapore and followed up for a minimum of 2 years were retrospectively reviewed. Surgeries were performed by both orthopaedic and neuro surgeons for various spinal conditions occurring due to degeneration, trauma, malignancies, and infection. Data that was extracted include demographic characteristics, comorbidities, diagnosis, activities of daily living (ADL) status, American Society of Anesthesiologists (ASA) physical status classification, American Spinal Injury Association neurological impairment grade, type of surgery, length of hospital stay, outcomes, and complications encountered. We primarily assessed the mortality and morbidity rates at 30 days, 6 months, 1 year, and 2 years following surgery. For assessment of postoperative morbidity, complications were classified into major and minor based on the grading’s suggested by Dindo et al.10 According to this grading, major complications included sepsis, pneumonia, deep surgical site infection, cerebrovascular accidents, myocardial infarction, pulmonary embolism, acute renal failure requiring dialysis and, nerve injury; minor complications included urinary tract infection, blood transfusion, mild renal insufficiency, deep vein thrombosis and, superficial surgical site infection. To identify risk factors, the selected cohort was grouped into those with mortality and without mortality. Bivariate comparisons were done to check if there was significant difference between the groups in relation to any of the extracted parameters. All data were analyzed using IBM SPSS Statistics ver. 23.0 (IBM Co., Armonk, NY, USA). Chi-square test was used to calculate the significance of difference between categorical variables and independent t-test or Mann-Whitney U-test was used to calculate the significance of difference between continuous variables. A p-value < 0.05 was considered statistically significant. This study (Ref: 2016/00743) was exempted from formal review by the domain-specific review board, National Healthcare Group, Singapore and was performed in accordance with the ethical standards mentioned in the most recent version of the 1964 declaration of Helsinki. Age (yr), mean (range) Sex Male Female Length of stay (day), mean (range) Operative site Cervical spine only Thoracic spine only Lumbar spine only Multiple segments Comorbidities, n (%) Diabetes mellitus Hypertension Hyperlipidemia Cardiac disease Stroke Pulmonary disease Multiple comorbidities* Etiology Degenerative spine disease Trauma Malignancy Infection ASA PS classific (...truncated)