Background: The intensity of the use of antidepressants in large populations can nowadays relatively easily be estimated using databases encompassing prescription data. There are shortcomings when using prescription databases as they contain no clinical data on patient illness. Antidepressants are prescribed for different illnesses, thus information on the indications could help when interpreting results from database studies on antidepressant drug use. The aim of this study is to investigate for which indications antidepressants are being prescribed in general practice in the Netherlands.
Methods: Data were obtained from the Second Dutch National Survey of General Practice, carried out by NIVEL (N=385,461). Patients, 18 years and older, who received an antidepressant prescription from a general practitioner in 2001 were selected (N=13,835). Indications for antidepressant drug prescribing were identified using time windows of different lengths.
Results: Antidepressants are most often being prescribed for depression (45.5%) and anxiety/panic disorders (17.2%). For these indications lengthening the time window around prescription date from 0 to 180 days resulted in an increase of 20-40% in antidepressant drug users identified with these indications.
Limitation: None of our selected indications could be identified in the physician-patient contact file for about a third of the antidepressant drug users. The study was performed in a general practice setting and did not include antidepressant users who consult psychiatrists.
Conclusion: GPs prescribe antidepressants predominantly for treating depression. However, using antidepressant drug as a proxy for identifying depressed patients in a prescription database should be done with caution and when possible in combination with clinical data.