Serious Adverse Events Significantly Reduce Patient-Reported Outcomes at 2-Year Follow-up

Study Design. This is an analysis of a prospective 2-year study on nonoperative patients enrolled in the Adult Symptomatic Lumbar Scoliosis (ASLS) National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) trial. Objective. The purpose was to evaluate the impact of serious adverse events (SAEs) on patient-reported outcomes (PROs) in nonoperative management of ASLS as measured by Scoliosis Research Society-22 (SRS-22), Oswestry Disability Index (ODI), and Short Form-12 (SF-12) at 2-year follow-up. Summary of Background Data. Little is known about PROs in the nonoperative management of ASLS or the prevalence and impact of SAEs on PROs. Methods. The ASLS trial dataset was analyzed to identify adult lumbar scoliosis patients electively choosing or randomly assigned to nonoperative treatment with minimum 2-year follow-up. Patient data were collected prospectively from 2010 to 2015 as part of NIAMS R01-AR055176-01A2 "A Multi-Centered Prospective Study of Quality of Life in Adult Scoliosis." SAEs were defined as life-threatening medical events, new significant or permanent disability, new or prolonged hospitalization, or death. Results. One hundred five nonoperative patients were studied to 2-year follow-up. Twenty-seven patients (25.7%) had 42 SAEs; 15 (14.3%) had a SAE during the first year. The SAE group had higher body mass index (29.4 vs. 25.2; P=0.008) and reported worse SRS-22 Function scores than the non-SAE group at baseline (3.3 vs. 3.6; P=0.024). At 2-year follow-up, SAE patients experienced less improvement (change) in SRS-22 Self-Image (-0.07 vs. 0.26; P=0.018) and Mental Health domains (-0.19 vs. 0.25; P=0.002) than non-SAE patients and had lower SRS-22 Function, Self-Image, Subscore, and SF-12 Mental and Physical component scores (MCS/PCS). Fewer SAE patients reached minimal clinically important difference (MCID) threshold in SRS-22 Mental Health (14.8% vs. 43.6%; P=0.01). Conclusion. A high percentage (25.7%) of ASLS patients managed nonoperatively experienced SAEs. Those patients who sustained a SAE had less improvement in reported outcomes. Level of Evidence: 2.