Longitudinal study of sleep patterns of United States Military Academy cadets.

STUDY OBJECTIVES The study provided an opportunity to observe sleep patterns in a college-age population attending the United States Military Academy. DESIGN This 4-year longitudinal study investigated sleep patterns of cadets. A stratified sample of 80 cadets had sleep patterns monitored using actigraphy for 8 months: one month in both fall and spring academic semesters over a 4-year period. SETTING Data were collected at the United States Military Academy, West Point, NY. PARTICIPANTS Participants were members of the class of 2007 (n˜1300) ranging in age from 17 to 22 when entering USMA. MEASUREMENTS AND RESULTS A sample of the class (n=80) wore wrist activity monitors and completed activity logs for one month in fall and spring academic semesters for the 4-year period. On average over the 4 years, cadets slept<5.5 h on school nights. Cadets napped extensively, perhaps in an attempt to compensate for chronic sleep debt. Cadets slept more during fall than spring semesters. Male and female cadet sleep patterns varied dramatically, with males consistently receiving less sleep than females (˜21 m for nighttime sleep and ˜23 m for daily sleep). CONCLUSIONS Cadet sleep at USMA is related to academic year, semester, season, sex, school day or weekend, and day of the week. These students suffer from chronic sleep debt. Restrictions imposed by the military academy limit the generalizability of the findings to other college age populations.