Drug Trials and Older People

Abstract

Older people are by far the largest users of prescription medications in Europe and North America – an unsurprising fact when we remember that older people are the ones that bear the greatest burden of disease. Recent observational reports have once again highlighted the association between multiple prescriptions and potential side effects in this age group, yet when we turn to the trials literature to guide our prescribing choices in older people, we find a woeful lack of suitable evidence to guide our practice. Many drug trials still specifically exclude older people, trial populations have far less co-morbid disease and co-prescription than real-world populations, and overly restrictive inclusion and exclusion criteria lead to unrepresentative study populations and can be seen as a manifestation of covert ageism. Worst of all, only a few trials report data on the effects of study treatments on physical function, overall quality of life or common problems of age (e.g. falls); without this information, it is impossible for clinicians and older patients to balance the benefits of treatment against the likely harms. It is in this context that Crome et al.’s report from the EU-funded PREDICT (increasing the PaRticipation of the ElDerly In Clinical Trials) study is timely. The authors carried out a survey of clinicians and other professionals involved in the drug trials and clinical care of older people across nine European countries, soliciting their views on the adequacy of current trial arrangements, asking about their attitudes to ageism in clinical trials, and seeking their views on what could be done to improve the situation. A spread of countries was included, with northern, eastern and southern European representation. This Europewide view is of particular importance, given not only the proposed focus on healthy ageing as part of the EU 8th Framework Programme funding stream for science, but also the increased participation in clinical trials by a wider range of countries; for example, the large HYVET (Hypertension in the Very Elderly Trial) blood pressure trial in older people enrolled many patients from Eastern Europe. The results showed considerable agreement across the nine countries, with a majority of respondents agreeing that older people were disadvantaged by current trial arrangements, and that the current arrangements were not satisfactory. In terms of differences, it is of particular interest that pharmaceutical company staff were least likely to view the current arrangements as unsatisfactory, and were more likely to believe that exclusion due to co-morbidity and polypharmacy were justified. Such attitudes are perhaps understandable; clinical trials cost pharmaceutical companies a great deal of money, and the need for larger sample sizes caused by the heterogeneity of age along with the high adverse event rate, further increase the costs to industry of testing new medications. Respondents from countries more recently admitted to the EU tended to view exclusion of older people as less of a problem. Geriatrics is a relatively young medical specialty, and is better established in some countries (e.g. the UK) than in others. Could this go some way to explaining the difference in attitudes shown in the PREDICT COMMENTARY Drugs Aging 2011; 28 (8): 679-68