A widespread problem people have is insufficient sleep. A new study has been done on men to see if there is a link to a chronic disease risk factor of bone loss and insufficient sleep. Insufficient sleep may be an unrecognized risk factor for bone loss. On Saturday, the results of this study will be presented at the Endocrine Society’s 99th annual meeting in Orlando, FL.
The study consisted of 10 healthy men. After three weeks of insufficient sleep consecutively, the study found reduced levels of a marker of bone formation in their blood. This is compared to people who have suffered from jet lag or shift work. The biological marker of bone resorption, or breakdown wasn’t changed on these men.
Research was done by Christine Swanson, M.D. while she was a fellow at Oregon Health & Science University in Portland, Oregon, with Drs. Eric S. Orwoll and Steven A. Shea. Research showed osteoporosis and bone fractures could come from the altered bone balance from insufficient sleep.
There are 54 million Americans with low bone mass or osteoporosis, but there is no clear cause for osteoporosis in 50 percent of Americans. It would help explain why there is no clear cause if it related to chronic sleep disturbance.
Circadian disruption has your internal body clock offset by the environment, and either your 24 hours is shorter or it is longer. This depends on whether you have a later chronotype, where you go to bed later, or early chronotype, where it’s early to bed and early to rise. The Centers for Disease Control and Prevention reported that insufficient sleep affects more than 25% of the U.S. population occasionally, and another 10% frequently. The study with these men also analyzed if there were health consequences of sleep restriction combined with circadian disruption.
This study was comparable to flying four time zones west every day for three weeks. For three weeks, in a lab the subjects went to sleep each day for four hours later than the prior day making it a 28-hour day. In a 24-hour period, the men were only allowed to sleep 5.6 hours. This part of the study was done to emulate people that work night shifts, otherwise known as shift work. At the beginning of the study, bloodwork was taken on each of the men and then again after the 3 weeks. The bloodwork measured bone biomarkers after sleep deprivation. During this 3-week study the men ate the same number of calories and nutrients. Out of the 10 men, 6 were between the ages of 20 to 27 and 4 were between 55 and 65.
There was limited funding, so the study couldn’t exam the serum from women; however, there are plans in the future to investigate sex differences to see if there is a sleep-bone relationship.
All the men in the study after three weeks had reduced levels of a bone formation marker compared to the beginning of the study. This reduction is called PINP. Additionally, the younger men had a greater decline. There was a 27% decline in the younger men versus 18% in the older. The study revealed old bone could break down without new bone being formed, while the levels of the bone resorption marker CTX did not change at all.
While bone growth and accrual are crucial for long-term skeleton health, this data is suggesting that sleep disruption earlier in life is detrimental to bone metabolism. There will need to be another study to see if there will be differences in the data with women.