Objective: To identify subject characteristics that may
be predictive of intentional dumping of metered-dose inhalers (MDIs)
during a clinical trial.
Design: Nebulizer Chronologs
(NCs; Medtrac Technologies; Lakewood, CO), which record the date and
time of each MDI actuation, were attached to the MDIs of participants
who were given a prescribed medication schedule to follow in a clinical
trial. Participants were not informed of the function of the NC or that
their medication use was being monitored.
Lung Health Study, a 5-year clinical trial to evaluate the effect of
intensive smoking cessation counseling and regular use of an inhaled
bronchodilator on the progression of COPD.
Participants: One hundred one smokers, 35 to 60 years
of age, with mild to moderate airways obstruction enrolled in The Lung
Measurements and results: Thirty of
these 101 participants (30%) actuated their inhalers > 100 times
within a 3-h interval on at least one occasion during the first year of
this 5-year trial. Only 1 of an additional 135 participants who had
full foreknowledge of the MDI monitoring capability of the NC did so.
Most of these dumping episodes occurred shortly before a clinic
follow-up visit, suggesting an active attempt to hide noncompliance
from the clinic staff. Whereas self-reported inhaler usage and canister
weights were similar for the “dumpers” and “nondumpers,” NC
data indicated significantly lower compliance rates for dumpers
(χ2; p < 0.05). When demographic variables, treatment
and clinic assignments, smoking status, pulmonary function test
results, respiratory symptoms, and disease history of dumpers and
nondumpers were analyzed, no predictors of dumping could be found.
Conclusions: Deception among noncompliers occurs frequently
in clinical trials, is often not revealed by the usual methods of
monitoring, and cannot be predicted by data readily available in