Introduction: The goal of this analysis is to define temporal and geographic trends in surgical treatment for Chiari Malformation Type I (CM) in a large privately-insured health care network.
Methods: We examined the Optum Insight dataset between 2001 and 2014 for all patients undergoing surgical treatment of CM in a managed care network of 58 million beneficiaries. Using a combination of International Classification of Disease (ICD) diagnosis codes and Current Procedural Terminology (CPT) codes, we identified CM and associated diagnoses and procedures over a 14-year period, highlighting temporal and geographic trends in performance of CMD as well as commonly associated procedures.
Results: 2,434 surgical procedures for CM decompression were carried out among beneficiaries in the 14-year interval. 34% were performed in patients less than 20 years old. The rate of Chiari decompression (CMD) increased 51% from the first half to the second half of the study period (p<0.001) among younger patients, while the rate of CMD among patients over 20 years of age was stable. A large gender difference was noted among adult patients. 78% of adult patients undergoing CMD were female compared to only 53% of children. Regional variability was identified among rates of CMD. The average annual rate of surgery ranged from 0.8 surgeries per 100,000 insured person years in the Pacific census division to 2.0 surgeries per 100,000 insured person years in the East South Central census division.
Conclusions: Analysis of a large nationwide healthcare network shows recently increasing rates of CMD in children while adult rates remained stable over the past 14 years.
Patient Care: Understanding the current national practice pattern for performance of CMD surgery will help identify best practices to improve clinical outcomes while avoiding unnecessary surgery.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe recent trends in rates of CMD in the adult and pediatric populations, 2) Discuss gender differences in performance of CMD, 3) Discuss geographic variation in performance of CMD.