Are clinical trial participants representative for patients with insomnia?

Introduction: It is vital to conduct clinical trials that test new medication in the intended patient population. However, given the often stringent inclusion and exclusion criteria of clinical trials, it can be debated whether the recruited patients are representative for the average patient with insomnia. Methods: Via advertisements in newspapers and consultation of sleep centers, N=79 patients with insomnia were recruited to participate in a clinical trial to examine next morning effects of hypnotic drugs on driving performance and cognitive performance. The current analysis examined recruitment failures of this clinical trial. Results: During initial screening, N=25 (31.6%) patients were excluded for practical issues and baseline demographics. Of them, N=8 were excluded because they either did not answer the phone, or had no further interest, or time to participate. N=2 were excluded because they did not speak Dutch. N=6 subject were either too young or too old, and N=6 did not meet the pre-set driving experience criteria. Another 3 subjects were not willing to stop driving for the duration of the study. Another N=49 (62%) patients were excluded for medical reasons: N=2 patients did not meet the criteria of insomnia, N=7 were engaged in shift work, N=2 reported having other sleep disturbances, and N=6 reported a sleep latency of more than 60 minutes. N=17 were excluded because they had comorbid psychiatric disease for which most of them received treatment (N=12) or had other health related issues (N=5). The other N=14 patients were not willing to stop their current treatment with hypnotic drugs. Of the N=5 subjects that were scheduled for screening, N=2 did not show up and were lost to follow up. N=3 subjects were scheduled for a single- blind 1-week placebo run-in week. These subjects failed due to a placebo response, i.e. they had a change in subjective sleep latency greater than 20 minutes. Conclusion: Of N=79 patients that were recruited, N=0 (0%) were included in the study. This data illustrates that patient's which are selected for participating in clinical trial are not always representative for patients in real life.