You Probably Sleep Better (or Worse) Than You Think . . .

. . . It all depends on your gender, according to Dutch researchers.  They investigated the claims made by older men and women about how well they sleep.  Their findings are published in the journal Sleep.

The study in question, which was part of the well-known Rotterdam study, involved almost 1,000 subjects between 59 and 79 years of age; 52% of them were women.  An actigraph – a movement meter worn like a watch – was used for 6 consecutive nights to measure sleep data – total sleep time, time to fall asleep, restlessness (or sleep efficiency), and so on.  Subjective sleep quality was recorded by the volunteer in a sleep diary and a questionnaire – the Pittsburgh Sleep Quality Index.   

In their subjective assessments, women reported shorter total sleep time, a longer time-to-fall-asleep, lower sleep efficiency, and overall worse sleep quality.  However, their actigraph readings they were found to have longer and less fragmented sleep than men.  Compared to men, women reported a 13.2 minutes shorter total sleep time, 10 minutes longer sleep onset time, and a 4.2% lower sleep efficiency.  But measured objectively (i.e. with the actigraph) women slept 16 minutes longer than men, had 1.2% higher sleep efficiency, and had less fragmented sleep. 

The difference between diary reported and total sleep time was greater in men (7.01 hours reported vs. 6.4 hours by actigraph) than in women, who reported 6.79 hours and actually slept 6.65 hours. 

In summary, the study indicates that elderly women sleep longer and better, and report their sleep duration more accurately, than men.  The author of the study report says the difference between the sexes may be the fact that women require more sleep than men, so that the same amount of sleep is satisfactory for men but not women.  Your homework is to discuss these results with your wife – if you dare.