Exclusion of Elderly People from Randomized Clinical Trials of Drugs for Ischemic Heart Disease

Authors

  • Florence T. Bourgeois MD, MPH,

    Corresponding author
    1. Division of Emergency Medicine, Boston Children's Hospital, Boston, Massachusetts
    2. Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
    3. Computational Health Informatics Program, Boston Children's Hospital, Boston, Massachusetts
    • Address correspondence to Florence T. Bourgeois, Computational Health Informatics Program, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115. E-mail: florence.bourgeois@childrens.harvard.edu

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  • Liat Orenstein MSc,

    1. Computational Health Informatics Program, Boston Children's Hospital, Boston, Massachusetts
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  • Sarita Ballakur,

    1. Faculty of Arts and Sciences, Brown University, Providence, Rhode Island
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  • Kenneth D. Mandl MD, MPH,

    1. Division of Emergency Medicine, Boston Children's Hospital, Boston, Massachusetts
    2. Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
    3. Computational Health Informatics Program, Boston Children's Hospital, Boston, Massachusetts
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  • John P. A. Ioannidis MD, DSc

    1. Stanford Prevention Research Center, Department of Medicine, School of Medicine, Stanford University, Stanford, California
    2. Department of Health Research and Policy, School of Medicine, Stanford University, Stanford, California
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Abstract

Objectives

To measure exclusion of elderly adults from randomized trials studying drug interventions for ischemic heart disease (IHD) and describe the characteristics of these trials.

Design

Cross-sectional analysis.

Setting

Interventional clinical trials studying a drug intervention for IHD that started in 2006 and after were identified in ClinicalTrials.gov. Data were extracted on study features, including age-based inclusion criteria. Data on participants and their age distribution were collected from trial publications, investigator inquiry, and result data in ClinicalTrials.gov.

Participants

Individuals aged 65 and older.

Measurements

Proportion of trials excluding individuals based on age, mean age of trial participants, and proportion of enrolled participants aged 65 and older and 75 and older.

Results

Of 839 identified trials, 446 (53%) explicitly excluded elderly adults. The most-frequent upper age limits were 80 (n = 164) and 75 (n = 114), with a median upper age limit of 80 (interquartile range 75–80). Trials with upper age limit exclusions tended to be smaller (median number of participants 100 vs 201, P < .001) and were more likely to be funded primarily by nonindustry sources (78.3% vs 70.0%, P = .006). The overall mean age of trial participants was 62.7 (mean maximum age 74). The estimated proportion of participants aged 65 and older was 42.5% and the estimated proportion aged 75 and older was 12.3%.

Conclusion

Despite the high burden of IHD in elderly adults, the majority of drug trials do not enroll participants reflective of age-related prevalence of the disease.

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