Drugs & Aging

, Volume 29, Issue 8, pp 669–679 | Cite as

Adverse Drug Reactions in a Population of Hospitalized Very Elderly Patients

  • Balamurugan Tangiisuran
  • J. Graham DaviesEmail author
  • Juliet E. Wright
  • Chakravarthi Rajkumar
Original Research Article



The aims of the study were to determine the rates, types, severity and preventability of adverse drug reactions (ADRs) in a hospitalized population of very elderly patients (over 80 years of age) and to identify factors that predispose the very elderly to an ADR.


An observational study was conducted in patients over 80 years of age admitted to four care of the elderly wards in Brighton and Sussex University Hospitals NHS Trust. The main outcome measures were the incidence of ADRs during inpatient stay in older patients and the identification of the major drug classes involved and the risk factors contributing to the occurrence of ADRs.


A total of 560 very elderly patients were recruited, 74 of whom experienced one or more ADR (83 in total), representing an incidence of 13.2% (95% CI 10.4, 16). Sixty-three percent of all ADRs were considered preventable, with 57 classified as serious and three as life threatening. The drug classes frequently implicated in ADRs were cardiovascular agents (34%), analgesic medications (18%) and anti-diabetic drugs (10%). Five variables were established as independent predictors of ADRs: number of medications, use of hypoglycaemic agents, history of hyperlipidaemia, raised white cell count on admission, and length of stay.


The ADR incidence reported in this population was no greater than that seen in other studies for both general medical patients and those elderly patients over 65 years of age. A significant proportion of ADRs were preventable, and this suggests that closer monitoring of high-risk elderly patients is needed to address this problem.


Adverse Drug Reaction Suspected Adverse Drug Reaction Cardiovascular Agent Abbreviate Mental Test Score Adverse Drug Reaction Case 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank Liz Cheek, senior lecturer from University of Brighton for her statistical advice and all other individuals who helped to make this study possible.

Contributors: All authors had full access to all the data (including statistical reports and tables) in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: BT, JGD and CR; acquisition of data: BT; analysis and interpretation of data: BT, JGD and CR; drafting of the manuscript: BT, JGD, CR and JEW; critical revision of the manuscript for important intellectual content: JGD, CR and JEW; statistical analysis: BT, JGD and CR; administrative, technical and material support: JGD, CR and JEW; and study supervision: BT, JGD, CR and JEW.

Funding: No sources of funding were used to conduct this study or prepare this article.

Competing interests: All authors declare that they have received no support from any organization for the submitted work; have no financial relationship with any organizations that might have an interest in the submitted work; and have no relationships or activities that could appear to have influenced the submitted work.

Ethical approval: The Research & Development Department at Brighton and Sussex Hospitals NHS Trust and also the National Research Ethics Service, Brighton West Research Ethics Committee (REC reference number: 08/H1111/43) approved the study.


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Copyright information

© Springer International Publishing AG 2012

Authors and Affiliations

  • Balamurugan Tangiisuran
    • 1
  • J. Graham Davies
    • 2
    Email author
  • Juliet E. Wright
    • 3
  • Chakravarthi Rajkumar
    • 3
  1. 1.Discipline of Clinical Pharmacy, School of Pharmaceutical SciencesUniversiti Sains MalaysiaPulau PinangMalaysia
  2. 2.Institute of Pharmaceutical ScienceKing’s College LondonLondonUK
  3. 3.Brighton and Sussex Medical SchoolUniversity of SussexBrightonUK

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