Effect of Diabetes on Patient-Reported Outcome Measures One Year After Laminoplasty for Cervical Spondylotic Myelopathy


A prospective spine surgery registry was launched at eight institutions in the greater Tokyo metropolitan area, after gaining approval from the University of Tokyo Hospital Clinical Research Support Center (10,335 -(3)) and institutional review boards of all participating hospitals, i.e. University of Tokyo Hospital, Japanese Red Cross Medical Center, Yokohama Rosai Hospital , Kanto Rosai Hospital, Japanese community health care organization Tokyo Shinjuku Medical Center, Toranomon Hospital, Japanese Red Cross Hospital Saitama, and Japanese Red Cross Hospital Musashino. This study was conducted in accordance with the relevant guidelines and ethical regulations/principles of the Declaration of Helsinki. The authors obtained an informed consent form from the patients with an opt-out method.

The patients

The authors evaluated a consecutive cohort of patients who were diagnosed with CSM and underwent posterior cervical decompression at 11 different institutions between April 2017 and October 2019. The diagnosis was made by board-certified spine surgeons. administration on the basis of neurological examinations as well as MRI or myelographic evaluations (existence of obliteration of the subarachnoid space with spinal cord compression). The inclusion criteria for the study were: symptomatic MCS (at least one clinical sign of myelopathy), surgical level between C3 and C7, evidence of cervical spinal cord compression on magnetic resonance imaging or to cervical computed tomography, and no previous cervical spine surgery. Exclusion criteria from the study were: diagnosis of posterior longitudinal ligament ossification, spinal tumors, trauma, or infectious diseases; under the age of 18; emergency surgery; surgery involving the thoracic spine; and fixation surgery.

Patient data collection

Data on the patients’ clinical characteristics, including age, sex, body mass index, current smoking history, American Society of Anesthesiologists (ASA) classification, and medical history, were collected retrospectively. Preoperative laboratory data were assessed. Patients with a fasting blood glucose of 126 mg/dL and a glycated hemoglobin (HbA1c) level of 6.5% or those previously diagnosed with diabetes by a diabetes specialist were considered to have diabetes15. Diabetes specialists at each hospital were able to adequately control the blood sugar levels of patients diagnosed with diabetes throughout the immediate perioperative period. Blood glucose levels were checked four times daily, and sliding scale insulin coverage was adopted to prevent perioperative hyperglycemia until the patient’s food intake stabilized. Surgical factors, including operative time and estimated blood loss, were recorded. Responsible surgeons were asked to report all intraoperative complications, including nerve root injuries and dural tears, and postoperative complications within 30 days of surgery.

Patient-Reported Outcome Measures

At baseline and one year after surgery, all patients were asked to complete a booklet of questionnaires, including the Japanese version of (1) Numerical Rating Scale (NRS), (2) Component Summary short-form 12 (PCS), (3) Mental Component Summary (MCS), (4) Euro quality of life 5-dimmension (EQ-5D)-3L to assess health-related quality of life16(5) Neck Disability Index (NDI) to assess pain-associated disability, and (6) Core Outcome Measures Index (COMI)-Neck17. The NRS measures pain intensity over the previous 4 weeks; scores range from 0 (no pain at all) to 10 (worst pain imaginable). To assess the effect of diabetes on axial pain and residual radiculopathy, the authors analyzed the following five NRS domains; pain in the neck, arms, hands, legs and feet. Each corresponding body part had been discussed in previous reports18. To determine satisfaction with the treatment, a 7-point Likert scale was used, in which patients were asked whether they were satisfied with the treatment, with possible answers of “very satisfied”, “satisfied”, “somewhat satisfied”. , ” Neither “. “, “dissatisfied”, “fairly dissatisfied” and “very dissatisfied”17.

statistical analyzes

Baseline demographic and clinical characteristics in the diabetic and non-diabetic groups were compared using the chi-square test for categorical variables and Student’s t-test. you-test for continuous variables. Students you-test was used to examine intergroup differences in pre- and postoperative NRS, PCS, MCS, EQ-5D, NDI, and COMI-Neck scores. For further evaluation of the difference in each outcome score, the authors calculated p-values ​​adjusted by the inverse probability weighting method after calculating propensity scores based on seven variables (age, sex, BMI, smoking status , ASA class, operative time and estimated blood level). loss) according to a previous report12.19. Correlations between diabetes-related factors (preoperative HbA1c level and fasting blood glucose) and postoperative outcomes were measured using Spearman’s rank correlation coefficients. We defined the correlation as the value of ρ > 0.40 with a p-value

The sample size for this study was calculated using G*Power version 3.1. With a diabetes prevalence of approximately 20-25%, as reported in a previous prospective database10,13,20a total sample size of at least 200 patients was required with a power > 0.8, significance level of P