title: Predictors of pain medication selection among patients diagnosed with fibromyalgia.
abstract: OBJECTIVE
  Several pharmacologic therapies have been recommended for managing fibromyalgia. However, the factors associated with each treatment initiation have not been well established. This study assessed factors that were associated with the use of duloxetine vs. other pain medications among patients with fibromyalgia.
  
  
  METHODS
  Administrative claims from a large, U.S. commercially insured population were analyzed using a retrospective cohort design. Patients with fibromyalgia who were 18 to 64 years old and initiated duloxetine vs. selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), venlafaxine, gabapentin, pregabalin, tramadol, or nontramadol opioids between January 1, 2007 and December 12, 2008 were selected. Treatment initiation was defined as no access to the same medication over the previous 90 days, with the most recent initiation date as the index date. All patients selected had at least one fibromyalgia diagnosis (ICD-9-CM: 729.1) in the 12 months prior to initiation of each study medication. Multiple logistic regression models were estimated to assess the predictors of initiating duloxetine vs. each of the other medications.
  
  
  RESULTS
  The study included 117,305 patients with fibromyalgia (48 years of age on average; 76% women) who initiated duloxetine (n = 5,827), SSRIs (n = 8,620), TCAs (n = 5,424), venlafaxine (n = 2,038), gabapentin (n = 5,733), pregabalin (n = 11,152), tramadol (n = 7,312), or nontramadol opioids (n = 71,199). Common fibromyalgia-related comorbidities were low back pain (31% to 49%), osteoarthritis (14% to 21%), and sleep disturbance (10% to 15%). Controlling for demographic and clinical characteristics, patients who received pregabalin in the prior 12-month period were more likely to initiate duloxetine. Patients from other treatment cohorts, except for those in the pregabalin and nontramadol opioid cohorts, were more likely to re-initiate the same prior medication than to begin treatment with duloxetine. Other predictors of duloxetine initiation included history of rheumatoid and sleep disturbance.
  
  
  CONCLUSIONS
  The presence of select comorbidities and prior use of certain medications were associated with the duloxetine initiation among working-age, commercially insured patients with fibromyalgia.
authors: United BioSource Corporation, Lexington, Massachusetts, USA.
authors: Luke
authors: L
authors: Boulanger
authors: Ning
authors: N
authors: Wu
authors: Shih-Yin
authors: SY
authors: Chen
authors: Saurabh
authors: S
authors: Nagar
authors: Kimberly
authors: K
authors: Fraser
authors: Mark J
authors: MJ
authors: Bernauer
authors: Zhenxiang
authors: Z
authors: Zhao
authors: Yang
authors: Y
authors: Zhao
mesh_terms: D000328:Adult; D000700:Analgesics / Q000627:therapeutic use; D000701:Analgesics, Opioid / Q000627:therapeutic use*; D000929:Antidepressive Agents, Tricyclic / Q000627:therapeutic use*; D015331:Cohort Studies; D000068736:Duloxetine Hydrochloride; D005260:Female; D005356:Fibromyalgia / Q000175:diagnosis* / Q000188:drug therapy* / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy* / Q000453:epidemiology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D013876:Thiophenes / Q000627:therapeutic use
chemical_list: D000700:Analgesics; D000701:Analgesics, Opioid; D000929:Antidepressive Agents, Tricyclic; D000068736:Duloxetine Hydrochloride; D017367:Selective Serotonin Reuptake Inhibitors; D013876:Thiophenes