Generalizability of pharmacologic and psychotherapy trial results for late-life unipolar depression

Abstract

Objectives

Despite evidence of low representativeness of clinical trial results for depression in adults, the generalizability of clinical trial results for late-life depression is unknown. This study sought to quantify the representativeness of pharmacologic and psychotherapy clinical trial results for late-life unipolar depression.

Method

Data were derived from the 2004–2005 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a nationally representative sample of 34,653 adults from the United States population. To assess the generalizability of clinical trial results for late-life depression, we applied a standard set of eligibility criteria representative of pharmacologic and psychotherapy clinical trials to all individuals aged 65 years and older in NESARC with a DSM-IV diagnosis of MDE and no lifetime history of mania/hypomania (n = 273) and in a subsample of individuals seeking help for depression (n = 78).

Results

More than four of ten respondents and about two of ten respondents would have been excluded by at least one exclusion criterion in a typical pharmacologic and psychotherapy efficacy trial, respectively. Similar results (i.e.41.1% and 25.9%, respectively) were found in the subsample of individuals seeking help for depression. Excess percentage of exclusion in typical pharmacologic studies was accounted for by the criterion “significant medical condition”. We also found that populations typically included in pharmacologic and psychotherapy clinical trials for late-life unipolar depression may substantially differ.

Conclusion

Psychotherapy trial results may be representative of most patients with late-life unipolar depression in routine clinical practice. By contrast, pharmacologic clinical trials may not be readily generalizable to community samples.

Keywords:

• Generalizability
• validity
• clinical trials
• depression
• older adults
• elderly
• antidepressants
• psychotherapy

Acknowledgements

The original data set for the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) is available from the National Institute on Alcohol Abuse and Alcoholism (http://www.niaaa.nih.gov).

Contributors

NH, LR, CB and FL designed the study. LR and JPS collected exclusion criteria. LR and NH undertook statistical analyses. LR and NH wrote the first draft of the manuscript. JPS, CB, PL, CH, FH, ET, AM, JFCL, ASS and FL reviewed the draft. All authors contributed to and have approved the final manuscript.

Disclaimer

The views and opinions expressed in this report are those of the authors and should not be construed to represent the views of any of the sponsoring organizations, agencies, or the US government.

Disclosure statement

FL is a member of the speakers/advisory boards for Janssen, Euthérapie, Lundbeck, Otsuka, and Roche. Other authors report no conflicts of interest.