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Development of a Risk Model for Adverse Drug Events in the Elderly

  • Pharmacovigilance
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Summary

The aim of this study was to develop a predictive model for adverse drug events (ADEs) in elderly patients. Socio-demographic and medical data were collected from chart reviews, computerised information and a patient interview, for a population of 929 elderly patients (aged > 65 years) whose admission to the Waveney/Braid Valley Hospital in Northern Ireland was not scheduled. A further 204 patients formed a validation group. An ADE score was assigned to each patient using a modified Naranjo algorithm scoring system. The ADE scores ranged from 0 to 8. For the purposes of developing a risk model, scores of 4 or more were considered to constitute a high risk of an ADE.

Logistic regression analysis was used to produce a risk model for ADEs in the elderly. Seven variables significantly influenced the risk of an elderly person developing an ADE. Prescribed digoxin [odds ratio (OR) = 1.99], antidepressants (OR = 5.79), and a number of disease states, i.e. gastrointestinal disorders (nausea, vomiting, diarrhoea) [OR = 2.16], chronic obstructive airways disease (OR = 2.41) and angina (OR = 0.17), significantly influenced ADE score. An abnormal potassium level (OR = 2.57) and patient belief that their medication was in some way responsible for their hospital admission (OR = 4.21) also significantly influenced ADE score.

Validation of the model revealed that it had a specificity of 69%, a sensitivity of 41%, with an overall accuracy of 63%. This model was therefore better at predicting elderly patients with ADE scores of 3 or less. Nonetheless, the variables highlighted are significant risk factors for ADEs in the elderly.

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References

  1. DHSS. People first: community care in Northern Ireland in the 1990s. HMSO, 1990

  2. Stewart RB. Polypharmacy in the elderly: a fait accompli? Ann Pharmacother 1990; 24: 321–3

    CAS  Google Scholar 

  3. Castleden CM, Pickles H. Suspected adverse drug reactions in elderly patients reported to the Committee on the Safety of Medicines. Br J Clin Pharmacol 1988; 26: 47–53

    Article  Google Scholar 

  4. Brennan TA, Leape LL, Laird NM, et al. Incidence of adverse events and negligence in hospitalized patients. Results of the Harvard Medical Practice Study I. N Engl J Med 1991; 324: 370–6

    Article  PubMed  CAS  Google Scholar 

  5. Leape LL, Brennan TA, Laird NM, 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

    Article  PubMed  CAS  Google Scholar 

  6. WHO. International drug monitoring: the role of national centres. WHO technical report series No 498 1972; 9

  7. Grymonpre RE, Mitenko PA, Sitar DS, et al. Drug-associated hospital admissions in older medical patients. J Am Geriatr Soc 1988; 36: 1092–8

    PubMed  CAS  Google Scholar 

  8. Karch FE, Lasagna L. Toward the operational identification of adverse drug reactions. Clin Pharmacol Ther 1977; 21: 247–54

    PubMed  CAS  Google Scholar 

  9. Kramer MS, Leventhal JM, Hutchinson TA, et al. An algorithm for the operational assessment of adverse drug reactions. 1. Background, description and instructions for use. JAMA 1979; 242: 623–32

    Article  PubMed  CAS  Google Scholar 

  10. Naranjo CA, Busto U, Sellers EM, et al. A method for assessing the probability of adverse drug reactions. Clin Pharmacol Ther 1981; 30: 239–45

    Article  PubMed  CAS  Google Scholar 

  11. Jones JK. Adverse drug reactions in the community health setting: approaches to recognizing, counselling, and reporting. Fam Comm Health 1982; 5: 58–67

    CAS  Google Scholar 

  12. Michel DJ, Knodel LC. Comparison of three algorithms used to evaluate adverse drug reactions. Am J Hosp Pharm 1986; 43: 1709–14

    PubMed  CAS  Google Scholar 

  13. Hosmer DW Jr, Lemeshow S. Applied logistic regression. New York: John Wiley and Sons, 1989

    Google Scholar 

  14. Siegel S, Castellan NJ Jr. Nonparametric statistics for the behavioural sciences. 2nd ed. New York: McGraw-Hill, 1988

    Google Scholar 

  15. Williamson J, Chopin JM. Adverse reactions to prescribed drugs in the elderly: a multicentre investigation. Age Ageing 1980; 9: 73–80

    Article  PubMed  CAS  Google Scholar 

  16. Popplewell PY, Henschke PJ. Acute admissions to a geriatric assessment unit. Med J Aust 1982; 1: 343–4

    PubMed  CAS  Google Scholar 

  17. Col N, Fanale JE, Kronholm P. The role of medication noncompliance and adverse drug reactions in hospitalizations in the elderly. Arch Intern Med 1990; 150: 841–5

    Article  PubMed  CAS  Google Scholar 

  18. Smuker WD, Kontak JR. Adverse drug reactions causing hospital admission in an elderly population: experience with a decision algorithm. J Am Board Fam Pract 1990; 3: 105–9

    Google Scholar 

  19. Jackson AE, Hall J, Chadha D. Elderly patients and their drugs. Avoiding hospital admissions. Pharm J 1992; 249 Suppl.: R25

    Google Scholar 

  20. Lindley CM, Tully MP, Paramsothy V, et al. Inappropriate medication is a major cause of adverse drug reactions in elderly patients. Age Ageing 1992; 21: 294–300

    Article  PubMed  CAS  Google Scholar 

  21. Nicolson A, Gladman CW, Smith CW, et al. Multicentre survey of adverse drug reactions in elderly people admitted to hospital. Age Ageing 1994; 23 Suppl 2: 40

    Google Scholar 

  22. Cunningham G, Dodd TRP, McMurdo MET, et al. Drug related hospital admissions of elderly patients. Age Ageing 1994; 23 Suppl 2: 6

    Google Scholar 

  23. Seidl LG, Thornton GF, Smith JW, et al. Studies on the epidemiology of adverse drug reactions. III. Reactions in patients on a general medical service. Bull Johns Hopkins Hospital 1966; 119: 299–315

    Google Scholar 

  24. Klein LE, German P, Levine D, et al. Medication problems among outpatients. A study with emphasis on the elderly. Arch Intern Med 1984; 144: 1185–8

    Article  PubMed  CAS  Google Scholar 

  25. Steel K, Gertmann PM, Crescenzi C, et al. Introgenic illness on a general medical service at a university hospital. New Engl J Med 1981; 304: 638–42

    Article  PubMed  CAS  Google Scholar 

  26. Ewy GA, Kapadia GG, Yao L, et al. Digoxin metabolism in the elderly. Circulation 1969; 39: 449–53

    Article  PubMed  CAS  Google Scholar 

  27. Vestal RE. Drug use in the elderly: a review of problems and special considerations. Drugs 1978; 16: 358

    Article  PubMed  CAS  Google Scholar 

  28. Ray WA, Griffin MR, Shorr DI. Adverse drug reactions and the elderly. Health Aff 1990; 9: 114–22

    Article  CAS  Google Scholar 

  29. Tinetti ME, Speechley M, Ginter SF. Risk factors for falls among elderly persons living in the community. New Engl J Med 1988; 319: 1701–7

    Article  PubMed  CAS  Google Scholar 

  30. Beard K. Adverse reactions as a cause of hospital admission in the aged. Drugs Aging 1992; 2: 356–67

    Article  PubMed  CAS  Google Scholar 

  31. Schneider JK, Mion LC, Frengley JD. Adverse drug reactions in an elderly outpatient population. Am J Hosp Pharm 1992; 49: 90–6

    PubMed  CAS  Google Scholar 

  32. Brawn LA, Castleden CM. Adverse drug reactions: an overview of special considerations in the management of the elderly patient. Drug Saf 1990; 5: 421–35

    Article  PubMed  CAS  Google Scholar 

  33. Schultz NJ, Angaran DM. Body electrolyte homeostatis. In: Dipiro JT, Talbert RL, Hayes PE, et al., editors. Pharmacotherapy: a pathophysiologic approach. New York: Elsevier, 1989: 1475–514

    Google Scholar 

  34. Stratton MA. Chronic obstructive lung disease. In: Dipiro JT, Talbert RL, Hayes PE, et al., editors. Pharmacotherapy: a pathophysiologic approach. New York: Elsevier, 1989: 368–82

    Google Scholar 

  35. Carbonin P, Pahor M, Bernabei R, et al. Is age an independent risk factor of adverse drug reactions in hospitalized medical patients? J Am Geriatr Soc 1991; 39: 1093–9

    PubMed  CAS  Google Scholar 

  36. Talbert RL. Ischemic heart disease. In: Dipiro JT, Talbert RL, Hayes PE, et al., editors. Pharmacotherapy: a pathophysiologic approach. New York: Elsevier, 1989: 173–12

    Google Scholar 

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McElnay, J.C., McCallion, C.R., Al-Deagi, F. et al. Development of a Risk Model for Adverse Drug Events in the Elderly. Clin. Drug Invest. 13, 47–55 (1997). https://doi.org/10.2165/00044011-199713010-00006

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