Sleep Series 4: Chronic effects of Sleep Deprivation

Chronic effects of Sleep Deprivation

Overtime, sleep loss can lead to severe health consequences when left untreated. These include increases in the risk of cardiovascular impairments, obesity, diabetes, gastrointestinal problems, and a depressed immune system.1-4

Researchers have examined how obesity relates to sleep.5 Two hormones play important roles in the regulation of food intake and body weight: leptin and ghrelin. Leptin functions to inhibit food intake while ghrelin functions to drive food intake.5,6 They work in opposition to regulate and control appetite. Unfortunately, lack of sleep disturbs hormone regulation resulting in an increase of food intake,5 which leads to an increase in obesity.6 Research also suggests that Individuals who are already sleep deprived pose a greater risk of developing diabetes.3-5,7

Sleep deprivation may also affect the cardiovascular system. Complications such as hypertension, cardiovascular disease, myocardial infractions, and heart disease have shown to correlate in individuals with sleep deprivation.8 A recent study suggests a dose-response relationship exists between hours worked and cardiovascular disease.9 They noted that individuals who worked an additional 10 hours (i.e., 55 hours per week) over a 10-year period had an increase in cardiovascular disease risk by at least 16 percent.9

Another chronic health effect of sleep deprivation is the immune system.3,10 A study found that inflammatory cytokines are created in individuals who are sleep deprived, meaning that they are at a greater risk for a depressed immune system and are likely to become sick.3 Additionally, when individuals are sleep deprived, their body produces less antioxidants, preventing the rid of damage-causing molecules,3 thus resulting in compromised immune functions. Another study found a connection with work duration and the immune system.11 They concluded that those who work longer shift duration are more likely to have a decreased immune system compared to those who work shorter shifts.

As continuous sleep loss becomes a repetitive behavior in individuals, they are more likely to have adverse health impacts. This includes obesity, diabetes, cardiovascular impairments, and compromised immune functions. In the next article, we will discuss various treatments that may help increase sleep quality among firefighter and emergency service personnel.


References
  1. Costa, Giovanni. 1996. "The Impact of Shift and Night Work on Health," Applied Ergonomics 27(1):9-16. doi:http://dx.doi.org/10.1016/0003-6870(95)00047-X
  2. Joffe, Mark D. 2006. "Emergency Department Provider Fatigue and Shift Concerns," Clinical Pediatric Emergency Medicine 7(4):248-254. doi:http://dx.doi.org/10.1016/j.cpem.2006.08.008
  3. Luyster, Faith S., et al. 2012. "Sleep: A Health Imperative," Sleep 35(6):727-734. doi:10.5665/sleep.1846
  4. Yaggi, H. Klar, et al. 2006. "Sleep Duration as a Risk Factor for the Development of Type 2 Diabetes," Diabetes Care 29(3):657. 
  5. Knutson, Kristen L. and Eve Van Cauter. 2008. "Associations between Sleep Loss and Increased Risk of Obesity and Diabetes," Annals of the New York Academy of Sciences 1129(1):287-304. doi:10.1196/annals.1417.033
  6. Klok, M. D., et al. 2007. "The Role of Leptin and Ghrelin in the Regulation of Food Intake and Body Weight in Humans: A Review," Obesity Reviews 8(1):21-34. doi:10.1111/j.1467-789X.2006.00270.x
  7. Knutson, Kristen L., et al. 2007. "The Metabolic Consequences of Sleep Deprivation," Sleep Medicine Reviews 11(3):163-178. doi:10.1016/j.smrv.2007.01.002
  8. Spiegel, Karine, et al. 1999. "Impact of Sleep Debt on Metabolic and Endocrine Function," The Lancet 354(9188):1435-1439. doi:10.1016/S0140-6736(99)01376-8
  9. Mullington, Janet M., et al. 2009. "Cardiovascular, Inflammatory and Metabolic Consequences of Sleep Deprivation," Progress in Cardiovascular Diseases 51(4):294-302. doi:10.1016/j.pcad.2008.10.003
  10. Conway, Sadie H., et al. 2016. "Dose–Response Relation between Work Hours and Cardiovascular Disease Risk: Findings from the Panel Study of Income Dynamics," Journal of Occupational Environmental Medicine 58(3):221-226. doi:10.1097/jom.0000000000000654
  11. Dinges, David F., et al. 1995. "Sleep Deprivation and Human Immune Function," Journal of Neuroimmunology 5(2):97-110. doi:10.1016/0960-5428(95)00002-J
  12. van der Hulst, Monique. 2003. "Long Workhours and Health," Scandinavian Journal of Work, Environment & Health 29(3):171-188. 


Next Series - Treatments (part 1)