International Journal of Legal Medicine

, Volume 133, Issue 2, pp 353–363 | Cite as

Completed suicides of citalopram users—the role of CYP genotypes and adverse drug interactions

  • Anna-Liina RahikainenEmail author
  • P. Vauhkonen
  • H. Pett
  • J. U. Palo
  • J. Haukka
  • I. Ojanperä
  • M. Niemi
  • Antti SajantilaEmail author
Original Article


Depression is known to be a risk factor for suicide. Currently, the most used antidepressants are selective serotonin reuptake inhibitors (SSRIs). Not all users, however, benefit from them. In such cases, treatment failure can be explained in part by genetic differences. In this study, we investigated the role of pharmacogenetic factors in citalopram-positive completed suicides (n = 349). Since citalopram is metabolized by CYP2C19 and CYP2D6 enzymes, the study population was genotyped for clinically relevant CYP2C19 and CYP2D6 polymorphisms and CYP2D6 copy number variation. To assess genetic differences between suicide cases and Finns in general, Finnish population samples (n = 855) were used as controls. Also, the role of drug interactions among suicide cases was evaluated. We found enrichment of a combined group of genetically predicted poor and ultrarapid metabolizer phenotypes (gMPs) of CYP2C19 among suicide victims compared to controls 0.356 [0.31–0.41] vs. 0.265 [0.24–0.30] (p = 0.0065). In CYP2D6 gMPs, there was no difference between cases and controls when the study population was analyzed as a whole. However, there were significantly more poor metabolizers among females who committed suicide by poisoning compared to female controls. In 8% of all drug poisoning deaths, lifetime drug-drug interaction was evaluated having a contribution to the fatal outcome. From clinical perspective, pharmacogenetic testing prior to initiation of SSRI drug could be beneficial. It may also be useful in medico-legal settings as it may elucidate obscure poisoning cases. Also, the possibility of unintentional drug interactions should be taken into account in drug poisoning deaths.


Postmortem Suicide Citalopram CYP2C19 CYP2D6 Drug interactions 



We thank Professor Emeritus Erkki Vuori for sharing his expertise.

Funding information

This study is financially supported by the Doctoral Programme in Population Health, University of Helsinki, and the Medical Research Foundation of Juhani Aho.

Compliance with ethical standards

This study was approved by the Coordinating Ethics Committee of the Helsinki and Uusimaa Hospital District.

Supplementary material

414_2018_1927_MOESM1_ESM.docx (176 kb)
ESM 1 (DOCX 175 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Forensic MedicineUniversity of HelsinkiHelsinkiFinland
  2. 2.Forensic Medicine UnitNational Institute for Health and WelfareHelsinkiFinland
  3. 3.Radboud Institute for Health SciencesRadboud University Medical CenterNijmegenthe Netherlands
  4. 4.Department of Clinical PharmacologyUniversity of Helsinki and Helsinki University Central HospitalHelsinkiFinland
  5. 5.Forensic Genetics UnitNational Institute for Health and WelfareHelsinkiFinland
  6. 6.Department of Public HealthUniversity of HelsinkiHelsinkiFinland
  7. 7.Forensic Toxicology UnitNational Institute for Health and WelfareHelsinkiFinland

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