Adverse drug reactions in elderly

Noah, B.A. and D.B. Brushwood, "Adverse Drug Reactions in Elderly Patients Alternative Approaches to Postmarket Surveillance," /. Hlth. Law, 33, 383-454 (2000). 

Corsonello A, Redone C, Corica F, Mussi C, Carbonin P, Antonelli Inc. Concealed renal insufficiency and adverse drug reactions in elderly hospitalized patients. Arch Intern Med 2005 165(7) 790-5. 

Routledge PA, CTMahony MS, Woodhouse KW. Adverse drug reactions in elderly patients. Br J Clin Pharmacol 2004 57 121-6. 

Horne R and Weinman J (1999) Patients beliefs about prescribed medicines and their role in adherence to treatment in chronic physical illness. J Psychosom Res 47(6) 555-567 Kannisto V, Lauritsen J, Thatcher AR et al. (1994) Reductions in mortality at advanced age several decades of evidence from 27 countries. Population and development review 20(4) 793-810 Lazarou J, Pomeranz BH, Corey PN (1998) Incidence of adverse drug reactions in hospitalized patients a meta- analysis of prospective studies. JAMA 279(15) 1200-1205 LeSage J (1991) Polypharmacy in geriatric patients. Nurs Clin North Am 26(2) 273-290 Pitkala KH, Strandberg TE, Tilvis RS (2001) Is it possible to reduce polypharmacy in the elderly ... 

It has been reported that there is a ninefold increased risk of having an adverse drug reaction when four or more drugs are taken simultaneously. In addition, 3-5 percent of all hospital admissions are related to adverse drug reactions, and of all the admissions for the elderly, 15-25 percent are complicated by an adverse drug reaction. Some of these reactions are life-threatening, and it is estimated that fatal adverse drug reactions in the United States may run in the thousands each year. 

Older The elderly are at increased risk of adverse drug reactions in general due to altered pharmacokinetics and polypharmacy. For example, reactions to halothane, chlorpromazine, flucloxacillin and co-amoxiclav are more common in elderly patients... 

French DG. Avoiding adverse drug reactions in the elderly patient Issues and strategies. Nurse Practitioner 1996 21 90, 96-7, 101-7. 

Beyth, R.J. Shorr, R.I. Epidemiology of adverse drug reactions in the elderly by drug class. Drugs Aging 1999, 14 (3), 231-239. 

Contributing Factors to Adverse Drug Reactions in the Elderly... 

Hanlon JT, Schmader K, Gray SL. Adverse drug reactions. In Delafuente JC, Stewart RB, eds. Therapeutics in the Elderly, 3d ed. Cincinnati, Harvey Whitney, 2000 289-314. 

Col N, Fanale JE, Kronholm P. The role of medication noncompliance and adverse drug reactions in hospitaUzations in the elderly. Arch Intern Med 1990 150 841-845. 

All drugs may cause adverse drug reactions (ADRs). These adverse effects are either unpredictable (hyper-sensitivity) or dose-depending. The risk of ADR is increased for several reasons in the elderly. The physiological alterations, the high number of medications and concomitant diseases increase the risk of ADR. This is further... 

Larson E, Kukull WA, Buchner D, et al. Adverse drug reactions associated with global cognitive impairment in elderly persons. Ann Intern Med 1987 107 169-173. 

It has been found that the vast majority of elderly patients being treated for a psychiatric disorder also have at least one physical disorder that requires medication 80% of all elderly patients in the United States have at least one chronic physical illness. Thus the elderly are the most likely group to experience adverse drug reactions and interactions. Studies show that patients over the age of 70 years have approximately twice as many adverse drug reactions as those under 50 years. 

Delirium, toxic confusional state, metabolic encephalopathy or acute confusional state are terms that are used interchangeably and often loosely to describe a syndrome of acutely disordered cognition, sometimes associated with reduced level of consciousness and abnormal attention (see Table 32.1). The syndrome is very common, especially in the elderly and in patients with dementia, and presentations vary widely both in the speed of onset and severity (Siddiqi et al. 2006). The differential diagnosis is broad and includes almost any medical condition, but the commonest causes are sepsis, adverse drug reaction and metabolic derangement (Francis et al. 1990). 

Veehof, L.J.G. Stewart, R.E. Meyboom-de Jong, B. Haaijer-Ruskamp, L.M. Adverse drug reactions and polypharmacy in the elderly in general practice. Eur. J. Clin. Pharmacol. 1999, 55, 533-536. 

The relative contributions of amoxicillin and clavula-nate to co-amoxiclav-induced hepatotoxicity are incompletely understood. In patients with co-amoxiclav hepatotoxicity, previous use of amoxicillin and rechallenge with amoxicillin were both uneventful, pointing to clavulanic acid as the more likely culprit (16). In a report from the UK, the incidence of liver injury with amoxicillin alone was 0.3 per 10000 prescriptions versus 1.7 with co-amoxiclav (32). The risk increased after multiple use and with increasing age to 1 per 1000 prescriptions of co-amoxiclav. The main message is that the combination should be used with caution in elderly patients. A patient who has had documented hepatotoxicity related to co-amoxiclav should be well informed about this adverse drug reaction and any future use should be prohibited. 

Onder G, Pedone C, Landi F, Cesari M, Della Vedova C, Bernabei R, Gambassi G. Adverse drug reactions as cause of hospital admissions results from the Italian Group of Pharmacoepidemiology in the Elderly (GIFA). J Am Geriatr Soc 2002 50(12) 1962-8. 

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