Study points to danger from astronauts taking sleep medication

11 Aug 2014

Astronauts experience problems with sleep, due to a number of reasons, including the rigorous training, and depend on sleeping pills to assist the body's natural sleep mechanism. However, a recently published study from Lancet Neurological Magazine revealed that astronauts often relied on sleeping pills before takeoff and during flights aboard the space shuttle.

Researchers from the University of Colorado, Harvard Medical School, and Brigham and Women's Hospital, in the 10-year study, analysed data which had been drawn from 21 astronauts on the International Space Station mission as also 64 other astronauts on 80 different shuttle missions aggregating 4,200 nights in space.

The study revealed that nearly 75 per cent of the ISS crew took occasional medications for sleep while on the space station, while even more used sleep aid medications on a majority of nights while in space. They also reported getting less than the usual amount of sleep nights prior to takeoff.

The study also concerned drugs such as Zaleplon and Zolpidem which, of course, led to greater concern than just lack of sleep.  Sleep aids came with multiple side effect warnings, including continued drowsiness and fatigue and most warned against operating heavy machinery, even after the drug was supposed to wear off.

On average, astronauts slept just less than six hours a night aboard both shuttle flights and ISS missions, much short of NASA's 8.5-hour guideline. Only 12 per cent of "sleep episodes" on shuttle missions and 24 per cent on ISS missions lasted seven plus hours, according to the research.

When these astronauts returned home, their seven-hour-plus sleep increased by 42 and 50 per cent, respectively.

According to Laura Barger from Brigham and Women's Hospital at the Harvard Medical School in Massachusetts, sleep deficiency was pervasive among crew members.

It was clear that more effective measures were needed to promote adequate sleep in crew members, both during training and spaceflight, as sleep deficiency had been associated with performance decrements in numerous laboratory and field-based studies.

On shuttle missions, medication was used on over half the nights and on four of the 13 shuttle missions all crew members took sleeping drugs on the same night 6 per cent of the time.

Routine use of the drugs, she added, was "of particular concern," given their potential side-effects on mental alertness and motor co-ordination.