Charalampis Giannadakis

Does Obesity Affect Outcomes After Decompressive Surgery for Lumbar Spinal Stenosis? A Multicenter, Observational, Registry-Based Study.

OBJECTIVE To evaluate the association between obesity and outcomes 1 year after laminectomy or microdecompression for lumbar spinal stenosis (LSS). METHODS The primary outcome measure was the Oswestry Disability Index (ODI). Obesity was defined as body mass index (BMI) ≥ 30. Prospective data were retrieved from the Norwegian Registry for Spine Surgery. RESULTS For all patients (n = 1473) the mean improvement in ODI at 1 year was 16.7 points (95% CI 15.7-17.7, P < 0.001). The improvement in ODI was 17.5 points in nonobese and 14.3 points in obese patients (P = 0 .007). Obese patients were less likely to achieve a minimal clinically important difference in ODI (defined as ≥ 8 points improvement) than nonobese patients (62.2 vs. 70.3%, P = 0.013). Obesity was identified as a negative predictor for ODI improvement in a multiple regression analysis (P < 0.001). Nonobese patients experienced more improvement in both back pain (0.7 points, P = 0.002) and leg pain (0.8 points, P = 0.001) measured by numeric rating scales. Duration of surgery was shorter for nonobese patients for both single- (79 vs. 89 minutes, P = 0.001) and 2-level (102 vs. 114 minutes, P = 0.004) surgery. There was no difference in complication rates (10.4% vs. 10.8%, P = 0.84). There was no difference in length of hospital stays for single- (2.7 vs. 3.0 days, P = 0.229) or 2-level (3.5 vs. 3.6 days, P = 0.704) surgery. CONCLUSIONS Both nonobese and obese patients report considerable clinical improvement 1 year after surgery for LSS, but improvement was less in obese patients. Obese patients were less likely to achieve a minimal clinically important difference.

Is There an Association Between Radiological Severity of Lumbar Spinal Stenosis and Disability, Pain, or Surgical Outcome?: A Multicenter Observational Study.

Study Design. Observational multicenter study. Objective. To evaluate if the severity of lumbar spinal stenosis (LSS) on magnetic resonance imaging (MRI) correlates with preoperative disability, pain, or surgical outcomes. Summary of Background Data. Surgeons use the morphological appearance of LSS on MRI for clinical decision making. However, the associations between radiological severity of LSS and disability, pain, or surgical outcomes remain unclear. Methods. Evaluation of severity of LSS on preoperative MRI according to the Schizas morphological classification. Patient and treatment data were retrieved from the Norwegian Registry for Spine Surgery. Preopertaive outcome measures were Oswestry disability index (ODI) and numeric rating scale (NRS) scores for back and leg pain. Postopertive outcome measures were ODI and NRS scores for back and leg pain at 1 year, changes in ODI and NRS scores after treatment, duration of surgery, length of hospital stay, and perioperative complications. Results. Of 202 patients included, 7 were found to have mild stenosis, 38 had moderate stenosis, 108 had severe stenosis, and 49 had extreme stenosis. The radiological severity of LSS was not linked to preoperative ODI (P = 0.089), NRS back pain (P = 0.273), or NRS leg pain (P = 0.282) scores. There were no differences in ODI (P = 0.933), NRS back pain (P = 0.652), or NRS leg pain (P = 0.912) scores after 1 year. The radiological severity of stenosis was not associated with change in ODI (P = 0.494), NRS back pain (P = 0.235), NRS leg pain (P = 0.790), duration of surgery (P = 0.661), length of hospital stay (P = 0.739), or perioperative complication rates (P = 0.467). Conclusion. Among patients who underwent decompressive surgery for LSS, radiological severity of stenosis was not associated with preoperative disability and pain, or clinical outcomes 1 year after surgery. In this patient group, the radiological severity of LSS has no clear clinical correlation and should therefore not be overemphasized in clinical decision making. Level of Evidence: 2

Surgery for Lumbar Spinal Stenosis in Individuals Aged 80 and Older: A Multicenter Observational Study

To compare clinical outcomes after decompressive surgery for central lumbar spinal stenosis (LSS) in individuals aged 80 and older with those of individuals aged 18–79.

Validation of intracranial hemorrhage in the Norwegian Patient Registry

Administrative health registries need to have accurate diagnoses and sufficient coverage in the population they serve in order to be useful in research. In this study, we investigated the proportion of discharge diagnoses of intracranial hemorrhage (ICH) that were coded correctly in the Norwegian Patient Registry (NPR).

Risk of intracranial hemorrhage in users of oral antithrombotic drugs: Study protocol for a nationwide study

Background A wide range of antithrombotic medications can be used in the prevention and treatment of thrombosis. Among hemorrhagic complications of antithrombotic drugs, intracranial hemorrhage may have particularly devastating consequences with high morbidity, disability and mortality rates. The incidence and risks of intracranial hemorrhage in patients on antithrombotic treatments from regular clinical practice outside clinical trials remain largely unknown. It is not known if results from clinical trials can be extrapolated to everyday clinical practice. We will conduct a nationwide study to investigate the risks and incidence rates of intracranial hemorrhage in users oral antithrombotic drugs in Norway from 2008 through 2014. Methods and design The aim of this nationwide study is to investigate the incidence rates of intracranial hemorrhage requiring hospitalization in users of oral antithrombotic drugs. The study will be conducted within the approximately 4.7 million inhabitants of Norway from January 1 st, 2008, to December 31 st, 2014. Treatment and outcome data are obtained from the Norwegian patient registry and the Norwegian prescription database. Trial registration number Clinicaltrials.gov (NCT02481011)

Risk of intracranial hemorrhage (RICH) in users of oral antithrombotic drugs: Nationwide pharmacoepidemiological study

Background The risks of intracranial haemorrhage (ICH) associated with antithrombotic drugs outside clinical trials are gaining increased attention. The aim of this nationwide study was to investigate the risk of ICH requiring hospital admission in users of antithrombotic drugs. Methods and findings Data from the Norwegian Patient Registry and Norwegian Prescription Database were linked on an individual level. The primary outcome was incidence rates of ICH associated with use of antithrombotic drugs. Secondary endpoints were risk of ICH and fatal outcome following ICH assessed by Cox models. Among 3,131,270 individuals ≥18 years old observed from 2008 through 2014, there were 729,818 users of antithrombotic medications and 22,111 ICH hospitalizations. Annual crude ICH rates per 100 person-years were 0.076 (95% CI, 0.075–0.077) in non-users and 0.30 (95% CI, 0.30–0.31) in users of antithrombotic medication, with the highest age and sex adjusted rates observed for aspirin-dipyridamole plus clopidogrel (0.44; 95% CI, 0.19–0.69), rivaroxaban plus aspirin (0.36; 95% CI, 0.16–0.56), warfarin plus aspirin (0.34; 95% CI, 0.26–0.43), and warfarin plus aspirin and clopidogrel (0.33; 95% CI, 0.073–0.60). With no antithrombotic medication as reference, the highest adjusted hazard ratios (HR) for ICH were observed for aspirin-dypiridamole plus clopidogrel (6.29; 95% CI 3.71–10.7), warfarin plus aspirin and clopidogrel (4.38; 95% CI 2.71–7.09), rivaroxaban plus aspirin (3.82; 95% CI, 2.46–5.95), and warfarin plus aspirin (3.40; 95% CI, 2.99–3.86). All antithrombotic medication regimens were associated with an increased risk of ICH, except dabigatran monotherapy (HR 1.20; 95% CI, 0.88–1.65) and dabigatran plus aspirin (HR 1.79; 95% CI, 0.96–3.34). Fatal outcome within 90 days was more common in users (2,603 of 8,055) than non-users (3,228 of 14,056) of antithrombotic medication (32.3% vs 23.0%, p<0.001), and was associated with use of warfarin plus aspirin and clopidogrel (HR 2.89; 95% CI, 1.49–5.60), warfarin plus aspirin (HR 1.37; 95% CI, 1.11–1.68), aspirin plus clopidogrel (HR 1.30; 95% CI, 1.05–1.61), and warfarin (HR 1.19; 95% CI, 1.09–1.31). Increased one-year mortality was observed in users of antithrombotic medication following hemorrhagic stroke, subdural hemorrhage, subarachnoid hemorrhage, and traumatic ICH (all p<0.001). Limitations include those inherent to observational studies including the inability to make causal inferences, certain assumptions regarding drug exposure, and the possibility of residual confounding. Conclusions The real-world incidence rates and risks of ICH were generally higher than reported in randomized controlled trials. There is still major room for improvement in terms of antithrombotic medication safety (clinicaltrials.gov NCT02481011).

Functional outcome and survival following spontaneous intracerebral hemorrhage: A retrospective population-based study

Accurate and reliable clinical and radiological predictors of intracerebral hemorrhage (ICH) outcomes are needed to optimize treatment of ICH. The aim of this study was to investigate functional outcome and identify predictors of severe disability or death following ICH.

Open discectomy vs microdiscectomy for lumbar disc herniation - a protocol for a pragmatic comparative effectiveness study

Introduction: Since the introduction of lumbar microdiscectomy in the 1970’s, many studies have attempted to compare the effectiveness of this method with that of standard open discectomy with conflicting results. This observational study is designed to compare the relative effectiveness of microdiscectomy (MD) with open discectomy (OD) for treating lumbar disc herniation, -within a large cohort, recruited from daily clinical practice. Methods and analysis: This study will include patients registered in the Norwegian Registry for Spine Surgery (NORspine). This clinical registry collects prospective data, including preoperative and postoperative outcome measures as well as individual and demographic parameters. The primary outcome is change in Oswestry disability index between baseline and 12 months after surgery. Secondary outcome measures are improvement of leg pain and changes in health related quality of life measured by the Euro-Qol-5D between baseline and 12 months after surgery, complications to surgery, duration of surgical procedures and length of hospital stay.

Response to comments on "Microsurgical decompression for central lumbar spinal stenosis: a single-center observational study".

Dear Editor, We would like to thank colleagues Nigro and Donnarumma for their comments on our study on microsurgical decompression for central lumbar spinal stenosis (LSS) without coexisting spondylolisthesis [1]. Symptomatic LSS is a highly prevalent condition, affecting as many as one out of ten individuals [2]. As the oldest segment of the population continues to grow, the number of patients having surgery for this condition will probably increase in the years to come [3]. As management of LSS has broad medical relevance, there is a large industry evolving around the different treatment options. As a consequence, LSS comes not only with the challenge of establishing the correct diagnosis but also selecting effective treatment that will not necessitate a large reallocation of healthcare resources. Over the last few years there have been numerous important developments in the surgical management of LSS. For patients with LSS and persistent severe symptoms, there is growing evidence that surgical decompression offers an advantage over non-surgical treatment [4–8]. Microsurgical decompression for LSS has gradually increased in popularity over the last decade, but this shift towards minimally invasive surgery took place before solid evidence was in place. However, two small randomised controlled trials (RCTs) and our recent multicentre observational study now demonstrate similar functional outcomes and safety profiles of microsurgical decompression and laminectomy [9–11]. In addition to the implementation of minimally invasive surgery, many spine surgeons shifted towards fusion procedures for LSS [3, 12] believing this improves both stability and outcomes. As this trend was backed by scarce evidence and there were worrisome reports concerning complications and costs [12–15], we had a restrictive policy concerning fusion surgery in LSS patients without spondylolisthesis or only mild spondylolisthesis on preoperative magnetic resonance imaging (MRI) while the data for our study in Acta Neurochirurgica were collected [1]. For patients without evident spondylolisthesis on preoperative MRI, lateral and/or flexion-extension radiographs were not routinely acquired or considered a requirement prior to surgery. Interestingly, two recent RCTs demonstrate that there is little value in adding fusion to decompression surgery for LSS [16, 17]. In the Swedish Spinal Stenosis Study (SSSS), 247 LSS patients with or without spondylolisthesis were randomly assigned to either decompression alone or decompression plus instrumented fusion [16] with results showing that fusion was associated with higher costs without improving functional outcomes. Ghogawala et al. [17] randomly assigned 66 patients with stenosis and coexisting spondylolisthesis to either decompression alone or decompression plus fusion. In addition to the SSSS trial, patients with spinal instability on flexion-extension radiographs were excluded. Ghogawala et al. found no differences between groups in back-pain-related disability (measured by the Oswestry disability index), and concluded that fusion did not justify the associated higher costs and longer duration of surgical procedures. In the wake of these two RCTs there has been a discussion regarding spinal instability [18], with opinions clearly divided on how or if it should influence surgical * Charalampis Giannadakis charalampis.giannadakis@ntnu.no