Published online Aug 26, 2013. doi: 10.13105/wjma.v1.i2.78
Revised: June 10, 2013
Accepted: July 18, 2013
Published online: August 26, 2013
AIM: To detect ophthalmic adverse drug reactions (ADRs), that occurred in Portugal from 2000 to 2009, through the utilization of administrative hospital databases. We also intended to compare the results of this methodology with spontaneous reporting.
METHODS: We conducted a retrospective nationwide study using hospital administrative databases, which included all inpatients and outpatients in all public hospitals in Portugal, from 2000 to 2009. We used International Classification of Diseases - 9th Revision - Clinical Modification (ICD-9-CM) coding data that allowed the detection of ADRs. We used WHO’s definition for ADR. We searched all of ICD-9-CM terms in Ophthalmology for codes that included “drug-induced”, “iatrogenic”, “toxic” and all other that could signal an ADR, such as “362.55 - toxic maculopathy” or “365.03 - steroid responders”, and also “E” codes (codes from E930 to E949.9, that exclude intoxications and errors).
RESULTS: From 11944725 hospitalizations or ambulatory episodes within that period of time, we identified 1524 probable ophthalmic ADRs (corresponding to a frequency of 1.28 per 10000 episodes) and an additional 100 possible ophthalmic ADRs. We used only 4 person-hours in the application of this methodology. A total of 113 spontaneous reports arose from ophthalmic ADRs from 2000 to 2009 in Portugal (frequency of 0.095 per 10000 episodes).To our knowledge, this was the first estimate of the frequency of ophthalmic ADRs through the use of databases, and the first nationwide estimate of ophthalmic ADRs, in Portugal. We identified 1524 probable ADRs and 100 possible ADRs.
CONCLUSION: This database methodology adapted for Ophthalmology may represent a new approach for the detection of ophthalmic ADRs, since these codes exist in the ICD-9-CM classification. Its performance was clearly superior to spontaneous reporting.
Core tip: We used International Classification of Diseases - 9th Revision - Clinical Modification coding data for the detection of adverse drug reactions (ADRs). From 11944725 episodes, we identified 1524 probable ophthalmic ADRs. 113 spontaneous reports arose from that population. This was the first nationwide study of ophthalmic ADRs and may represent a new Pharmacovigilance approach, with a higher detection than spontaneous reporting.