Effects of dextroamphetamine, caffeine and modafinil on psychomotor vigilance test performance after 44 h of continuous wakefulness

Research design/methodology

TYPE: Randomized controlled trial

VALIDITY: The study was well designed aside from some technology-related data collection failures.
ENVIRONMENT: The study was conducted in two phases: a non-residential phase was conducted using data collection devices in the home and a residential phase was conducted in a laboratory at the Walter Reed Medical Center.

Research question

Researchers wanted to investigate the effect of dextroamphetamine, caffeine and modafinil compared with placebo on psychomotor vigilance testing (PVT) when given to subjects after a short period of sleeplessness (44 hours). Repeated assessment of PVT were taken, detailed information about sleep patterns were recorded and evaluated in the pre-drug, post-drug and post-recovery phases of the study.

Patient/Problem/Population definition

PROBLEM: Facilitate the investigation of the effects of single dose stimulant use on PVT after a short period of sleeplessness.  Using wearable sleep recording devices to facilitate sleep study investigation.
POPULATION: Adults with typical sleep patterns and typical caffeine and/or stimulant use patterns with no other complicating conditions.
TYPE: This study involved a therapeutic drug intervention.

Intervention

Therapeutic intervention was the use of dextroamphetamine, caffeine, and modafinil - or placebo.  Using wrist actigraphs to monitor subjects' sleep and wake patterns (Ambulatory Monitoring Inc., Ardsley, NY, USA, and Compumedics SIESTA PSG recording units).

Outcome

The administration of a single dose of dextroamphetamine, caffeine, modafinil resulted in PVT performance returning to near baseline compared with the placebo group. This was significant to p<.05. One drawback in the effect was that recovery sleep was different in each group with sleep returning last for the dextroamphetamine group.

Application of results to patient care

The authors expressed difficulty with data collection including data loss using the PSG units.  To recover from this, subjects had to be added to the study and each arm was reduced.  This did not appear to adversely affect the results.  Particular attention must be paid to the half-life of the stimulants being studied as subjects expressed differences in achieving recovery sleep under different drug conditions.

Further areas for research  

Perhaps the most significant element of this study for mobile medical computing is noting the significance of robust data collection when mobile medical devices are employed.