The Journal of the American Medical Association (JAMAO) study followed 495 healthy middle aged participants for 5 years. At the beginning of the study participants had no detectable calcification in their arteries. Numerous factors were considered in relation to those who developed calcification such as age, sex, race, education, lipids, BMI, diabetes, etc. as well as sleep related information. After a comprehensive analysis it was discovered that a third of those in the study who slept less than 5 hours per night had calcified arteries. The risk went down to only 1 in 10 for those in the study who slept less than 6 hours per night. Study participants who slept more than 7 hours per night had the lowest risk.

While the study could not say that a lack of sleep actually causes the calcification, a strong association is definitely present.

For more information see:

“Skipping sleep ‘hardens arteries’” by BBC News. Wednesday, 24 December 2008. Can be found online at http://news.bbc.co.uk/1/hi/health/7796922.stm

“Short Sleep Duration and Incident Coronary Artery Calcification” by Christopher Ryan King, BS; Kristen L. Knutson, PhD; Paul J. Rathouz, PhD; Steve Sidney, MD, MPH; Kiang Liu, PhD; Diane S. Lauderdale, PhD. JAMA. 2008;300(24):2859-2866. The study can be found online at http://jama.ama-assn.org/cgi/content/short/300/24/2859.