Geographic variation in opioid prescribing for acute, work-related, low back pain and associated factors: a multilevel analysis.
BACKGROUND
Given reports about variation in opioid prescribing, concerns about increasing opioid use and its associated negative consequences make understanding the sources of variability important. The aims of the study were to assess the extent of and factors associated with geographic variation in early opioid prescribing for acute, work-related, low back pain (LBP).


METHODS
Cases were selected from workers compensation administrative data filed between January 1, 2002 and December 31, 2003 and included claims from states with more than 40 cases. Early opioid prescribing (one or more prescriptions within first 15 days) was the outcome. Weighted coefficient of variation (wCOV) estimated geographic variation, and multilevel models measured variability controlling for individual and contextual factors.


RESULTS
Of the 8,262 claimants, 21.3% received at least one early opioid prescription. Significant between-state variation was found (wCOV = 53%), from 5.7% (Massachusetts) to 52.9% (South Carolina). Seventy-nine percent of the between-state variation was explained by three contextual factors: state household income inequality (prevalence ratio [PR] 1.06, 95% confidence interval [CI] = 1.01, 1.12), number of physicians per capita (PR 0.99, 95% CI = 0.98, 0.99), and workers compensation cost containment effort score (PR 1.12, 95% CI = 1.02, 1.24). Individual-level factors, including severity, explained only a small portion of the geographic variability.


CONCLUSIONS
Geographic variation of early opioid prescribing for acute LBP is important and almost fully explained by state-level contextual factors. The study suggests that clinician and patient interaction and the subsequent decision to use opioids are substantially framed by social conditions and control systems. Am. J. Ind. Med. 52:162-171, 2009. (c) 2008 Wiley-Liss, Inc.
Webster
Barbara S
BS
Liberty Mutual Research Institute for Safety, Center for Disability Research, Hopkinton, Massachusetts, USA. barbara.webster@libertymutual.com
Cifuentes
Manuel
M
Verma
Santosh
S
Pransky
Glenn
G
D000208:Acute Disease; D000328:Adult; D000701:Analgesics, Opioid / Q000627:therapeutic use*; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000188:drug therapy* / Q000453:epidemiology / Q000209:etiology; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D009784:Occupational Diseases / Q000188:drug therapy* / Q000453:epidemiology; D016273:Occupational Exposure / Q000009:adverse effects*; D009825:Oklahoma / Q000453:epidemiology; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D013022:South Carolina / Q000453:epidemiology; D014707:Vermont / Q000453:epidemiology; D014942:Workers' Compensation / Q000706:statistics & numerical data; D017132:Workplace / Q000706:statistics & numerical data
D000701:Analgesics, Opioid