Investigating the factors influencing the prescription of antidepressants with no FDA approved indication in the United States between 2006-2009

Purpose: Prescribing of antidepressants has increased over the past several years and was the third most prescribed therapeutic class in 2007.  From 2006-2009, approximately 40% of antidepressants were prescribed without an FDA-approved indication.  The pharmacological class of the antidepressants [selective serotonin reuptake inhibitor (SSRI) or serotonin-norepinephrine reuptake inhibitor (SNRI)], along with other previously identified factors seem to play a role in whether or not an antidepressant is prescribed for an FDA approved indication.

Methods: This was a retrospective cross-sectional study of adults who received an antidepressant prescription between 2006-2009.  The study utilizes the publicly available de-identified National Ambulatory Medical Care Survey database administered by the National Center for Health Statistics of the Centers for Disease Control and Prevention.  Psychiatric and mental health visits were determined by a mental health diagnosis according to ICD-9CM codes 290-319; indication of depression listed, or use of antidepressants with an FDA approved indication for the prescription.  A subset of the data, 4,894 visits, were analyzed to examine all antidepressants prescribed without FDA approved indications or psychiatric diagnosis for the visit.  Weighted Odds Ratios were utilized to determine the association of patient and provider characteristics influencing receiving an antidepressant with no FDA approved indication.

Results: The SSRI and SNRI classes accounted for 67% of antidepressants received without FDA approved indications.  Receiving an SSRI/SNRI with no FDA approved indication was significantly associated with being female [1.32 (1.09-1.59)], Caucasian [1.93 (1.25-1.98)] and seen by general practice physician [1.32 (1.09-1.59)].  Both chronic problems and progress visit were the most common reasons for visit.  

Conclusion: SSRIs/SNRIs were the most commonly prescribed antidepressant classes without an FDA approved indication.  Sex, race and physician were associated with the class of antidepressant given, however further investigation is needed to identify specific factors that may be important to reducing the prescription of antidepressants.