Anne Buzzell1,2, Jonviea D Chamberlain3,4, Inge Eriks-Hoogland5, Xavier Jordan6, Martin Schubert7, Marcel Zwahlen8, Martin W G Brinkhof9,10. 1. Swiss Paraplegic Research, Nottwil, Switzerland. 2. Department of Health Sciences and Medicine, University of Lucerne, Lucerne, Switzerland. 3. University of Bordeaux, Inserm, Bordeaux Population Health Research Center, Team VINTAGE, UMR1219, Bordeaux, France. 4. France Inserm, CIC1401-EC, Bordeaux, France. 5. Swiss Paraplegic Centre, Nottwil, Switzerland. 6. Clinique Romande de Réadaptation, Sion, Switzerland. 7. Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland. 8. Institute of Social and Preventative Medicine, University of Bern, Bern, Switzerland. 9. Swiss Paraplegic Research, Nottwil, Switzerland. martin.brinkhof@paraplegie.ch. 10. Department of Health Sciences and Medicine, University of Lucerne, Lucerne, Switzerland. martin.brinkhof@paraplegie.ch.
Abstract
STUDY DESIGN: Observational, population-based cohort study. OBJECTIVES: To evaluate the origin and contribution to excess of survival differences following non-traumatic spinal cord injury (NTSCI) using etiology as proxy for variation in underlying health condition. SETTING: Specialized rehabilitation centers in Switzerland. METHODS: Medical record data collected by the Swiss Spinal Cord Injury cohort (SwiSCI) study were linked with mortality information from the Swiss National Cohort. Considering contemporary theory and empirical evidence, a directed acyclic graph (DAG) was developed to formally evaluate causal differences among NTSCI etiologies, relative to traumatic SCI (TSCI). Statistical inference was contingent on hazard ratios (HRs) and marginal survival differences, derived using flexible parametric modeling. RESULTS: 3643 individuals (NTSCI = 1357; TSCI = 2286) diagnosed with SCI between 1990 and 2011 were included, contributing a cumulative 41,344 person-years and 1323 deaths. Test statistics confirmed DAG-dataset consistency. As compared to TSCI, mortality was elevated in all NTSCI etiological groups; malignant etiologies had the highest HRs (10; 95% CI, 8.0 to 14) followed by infection (2.6; 1.8 to 3.6) and vascular (2.5; 2.0 to 3.2) etiology groups. At the attained age of 55, the estimated reduction in survival among non-malignant etiologies was 9.4% (5.8 to 13) at 5 years and 17% (11 to 23) at 20 years. CONCLUSIONS: Causal differences in survival among NTSCI etiological groups are likely a result of chronic variation in health conditions. This study supports the development of long-term interdisciplinary management and policy for individuals with NTSCI, specific to etiology.
STUDY DESIGN: Observational, population-based cohort study. OBJECTIVES: To evaluate the origin and contribution to excess of survival differences following non-traumatic spinal cord injury (NTSCI) using etiology as proxy for variation in underlying health condition. SETTING: Specialized rehabilitation centers in Switzerland. METHODS: Medical record data collected by the Swiss Spinal Cord Injury cohort (SwiSCI) study were linked with mortality information from the Swiss National Cohort. Considering contemporary theory and empirical evidence, a directed acyclic graph (DAG) was developed to formally evaluate causal differences among NTSCI etiologies, relative to traumatic SCI (TSCI). Statistical inference was contingent on hazard ratios (HRs) and marginal survival differences, derived using flexible parametric modeling. RESULTS: 3643 individuals (NTSCI = 1357; TSCI = 2286) diagnosed with SCI between 1990 and 2011 were included, contributing a cumulative 41,344 person-years and 1323 deaths. Test statistics confirmed DAG-dataset consistency. As compared to TSCI, mortality was elevated in all NTSCI etiological groups; malignant etiologies had the highest HRs (10; 95% CI, 8.0 to 14) followed by infection (2.6; 1.8 to 3.6) and vascular (2.5; 2.0 to 3.2) etiology groups. At the attained age of 55, the estimated reduction in survival among non-malignant etiologies was 9.4% (5.8 to 13) at 5 years and 17% (11 to 23) at 20 years. CONCLUSIONS: Causal differences in survival among NTSCI etiological groups are likely a result of chronic variation in health conditions. This study supports the development of long-term interdisciplinary management and policy for individuals with NTSCI, specific to etiology.
Authors: Johannes Textor; Benito van der Zander; Mark S Gilthorpe; Maciej Liskiewicz; George Th Ellison Journal: Int J Epidemiol Date: 2016-12-01 Impact factor: 7.196
Authors: A Buzzell; J D Chamberlain; H P Gmünder; K Hug; X Jordan; M Schubert; M W G Brinkhof Journal: Spinal Cord Date: 2018-11-09 Impact factor: 2.772