Abstracts

RATIONALE: It is not uncommon for large, multi-center clinical trials to have difficulty maintaining adequate enrollment. Significant medical economic problems associated with aging are known to interfere with the ability of older patients to participate in research studies. Social problems are a major deterrent to patients participating in research studies.
METHODS: This was a retrospective analysis of eligibility criteria from VA Coop Study [pound]428, [dsquote]Treatment of Seizures in the Elderly Population[dsquote]. Sixteen VAMC[scquote]s are presently participating in a study to evaluate the efficacy and tolerability of gabapentin (GBP), lamotrigine (LTG), and carbamazepine (CBZ) in the treatment of seizures in individuals 60 years or older. Screening records were reviewed to determine reason(s) for ineligibility into the trial. Refusal data collection forms were sent to all centers to determine the most common reasons for refusals.
RESULTS: 1,057 patients have been screened. Of these, 463 were enrolled and 594 were excluded. The number excluded is likely to be an underestimate since screening forms were not done on every potential patient. The most common exclusion reasons were no seizures in the last 3 months (39 %), unstable medical disorders (16 %), unable to give consent (15 %), questionable compliance (14.6 %), satisfied with current treatment (14.5%) and refused (10.4%). Other exclusions included treated with study drug(s) (7.7 %), alcohol withdrawal (4%), psychiatric disorders (3.8 %), chronic barbiturates (3.6 %), metabolic seizures (2.6%), street drugs (1.6%), enrolled in other research (1.4%), allergy (1.2 %), acute CNS infection (0.41 %) and HIV (0.14%). Reasons for refusals were spouse/family refused (30.4%), patient denial of diagnosis of epilepsy (30.4%), too many pills (14.8%), travel (8.9%), nursing home refusal (5.4%), and refused to be [dsquote]guinea pig[dsquote] (3.4%).
CONCLUSIONS: Co-morbid diseases impact the older patient[scquote]s ability to participate in clinical trials. Cognitive impairment related to aging contributes to the inability of older patients to understand and give informed consent. Elderly patients are more likely to refuse participation in research than younger adults. Inability of older patients to cope with a diagnosis of epilepsy and deny their condition is not uncommon. Approval from family members/caregivers becomes more important in determining participation.
Support: VA Cooperative Studies Program