Abstract
Adverse drug events in hospitalized patients lead to increased morbidity, mortality and costs. Early detection of adverse drug events could aid in the prevention of these adverse outcomes. A cost‐effective system for the early detection of adverse drug events should focus on high risk patients. A study was set up with the primary aim to identify characteristics that are associated with the development of adverse drug events (ADEs) in hospitalized patients.ADE reports were gathered from physicians and nurses (spontaneous reports) and from patients after intensive ward interviews by hospital pharmacists. All patients admitted to the internal medicine wards of two Dutch hospitals, during a two month period, were included.The following characteristics were analyzed for their potential relationship to the occurence of ADEs: age (categorized), gender, number of drugs prescribed during hospital stay, types of drugs used and changes in drug use on admission.Age was found to be inversely associated with the development of ADEs (OR 0.36, CI 0.21‐0.61 for age category > 80 years; OR 0.56; CI 0.31‐1.02 for age category 75‐80 years and OR 0.69; CI 0.42‐1.11 for age category 60‐74 years). Furthermore, statistically significant associations were found for the number of drugs prescribed per hospitalized patient (for the class of 4‐6 drugs per patient OR 2.61, CI 1.32‐5.18), for newly prescribed drugs (OR 6.65, CI 2.63‐16.81) and for the cessation of drugs on hospital admission (OR 1.50, CI 1.02‐2.20). The use of gastrointestinal drugs (OR 2.13, CI 1.32‐3.45), central nervous system drugs (OR 1.66, CI 1.07‐2.57) and antibiotics (OR 2.44, CI 1.65‐3.60) were associated with the development of ADEs, when compared to all other drugs taken by the patients.In this study, the most important risk factors are the number of drugs used per patient and the starting of a new drug during hospitalization. As most hospitalized patients start new drug therapies while in hospital, this seems an inappropriate focus. However, careful monitoring of patients using more than 7 drugs at a time may be possible in a cost‐effective system for the early detection of ADEs.
References
Leape LL, Brennan TA, Laird N, Lawthers AG, Localio AR, Barnes BA, et al. The nature of adverse events in hospitalized patients. Results of the Harvard Medical Practice Study II. N Engl J Med 1991;324:377-84.
Classen DC, Pestotnik SL, Scott Evans R, Lloyd JF, Burke JP. Adverse drug events in hospitalized patients. JAMA 1997;277:301-6.
Lazarou J, Pomeranz BH, Corey PN. Incidence of adverse drug events in hospitalized patients. A meta-analysis of prospective studies. JAMA 1998;279:1200-05.
Anonymous. International monitoring of adverse reactions to drugs. Adverse reaction terminology. Uppsala: WHO Collaborating Centre for International Drug Monitoring, 1995.
Anonymous. Anatomical Therapeutic Chemical (ATC) classification index. Oslo: WHO Collaborating Centre for Drug Statistics Methodology, 1994.
Mitchell AS, Henry DA, Sanson-Fisher R, O'Connell DL. Patients as a direct source of information on adverse drug events. BMJ 1988;297:891-3.
Hoigné R, Lawson DH, Weber E. Risk factors for adverse drug events-epidemiological approaches. Eur J Clin Pharmacol 1990;39:321-5.
Brawn LA, Castleden CM. Adverse drug events-an overview of special considerations in the management of the elderly patient. Drug Safety 1990;5:421-35.
Denham MJ. Adverse drug events. Br Med Bull 1990;46:53-62.
Lamy PP. Adverse drug effects. Clin Geriatr Med 1990;6:293-307.
Gurwitz JH, Avorn J. The ambiguous relation between aging and adverse drug events. Ann Intern Med 1991;114:956-66.
Lindley CM, Tully MP, Paramsothy V, Tallis RC. Inappropriate medication is a major cause of adverse drug events in elderly patients. Age and Ageing 1992;21:294-300.
Atkin PA, Shenfield GM. Medication-related adverse reactions and the elderly: a literature review. Adverse Drug React Toxicol Rev 1995;14:175-91.
Holland EG, Degruy FV. Drug-induced disorders. Am Family Physician 1997;56:178-88.
D'Arcy PF. Adverse drug events in hospital and in the community. Adverse Drug React Toxicol Rev 1997;16:95-101.
Carbonin P, Pahor M, Bernabei R, Sgadari A. Is age an independent risk factor of adverse drug events in hospitalized medical patients? J Am Geriatr Soc 1991;39:1093-99.
Moore N, Lecointre D, Noblet C, Mabille M. Frequency and cost of serious adverse drug events in a department of general medicine. Br J Clin Pharmacol 1998;45:301-8.
Mann RD, Rawlins MD, Fletcher P, Wood SM. Age and the spontaneous reporting of adverse reactions in the United Kingdom. Pharmacoepidemiology and Drug Safety 1992;1:19-23.
Kando JC, Yonkers KA, Cole JO. Gender as a risk factor for adverse events to medications. Drugs 1995;50:1-6.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
van den Bemt, P., Egberts, A., Lenderink, A. et al. Risk factors for the development of adverse drug events in hospitalized patients. Pharm World Sci 22, 62–66 (2000). https://doi.org/10.1023/A:1008721321016
Issue Date:
DOI: https://doi.org/10.1023/A:1008721321016