The effects of sleep deprivation that can occur in cases where the individual is obtaining less than 7 hours of sleepÂ a night are similar to those experienced by someone who has gone without sleep completely for 1 or 2 nights. Some of the results of sleep deprivation are impaired concentration and attention, poor judgment, relationship problems and the potential for anxiety and depression. Work-related errors, accidents and performance declines can also occur.
Some of the physiological effects of chronic sleep deprivation can include hand tremors, headaches, increased blood pressure, seizures and elevated levels of stress hormones. A complete absence of sleep over an extended period of time, other than in cases of fatal familial insomnia, has not been clinically observed in humans, but it has been shown to cause death in laboratory animals.
One out of every five serious vehicle accidents is related to sleep deprivation as documented by the National Academy of Sleep Medicine. Sleep deprivation was ruled to be a significant factor in the nuclear accidents at both Three Mile Island and Chernobyl. The explosion of the space shuttle Challenger and the oil spill released by the Exxon Valdez oil tanker have also been attributed to sleep deprivation. Medical errors occurring at hospitals can be reduced by up to 36 percent if doctors' shifts were kept below 16 hours a day and under 80 hours a week as reported by a study made by the Harvard Medical School Division of Sleep Medicine in 2004.