Sleep disorders increase blood pressure

Breathing problems during sleep seem to raise blood pressure in shift workers as compared to day workers. Sleep-disordered breathing (SDB) describes a group of disorders affecting breathing during sleep. The most common type is obstructive sleep apnoea, in which the back of the throat collapses periodically during sleep and breathing stops for a few moments until the patient wakes up to resume breathing again. Since the patient is unable to get a good night's sleep due to obstructive breathing, they often feel sleepy during the day with sluggish mental performance. Researchers from the University of Tsukuba, Japan found that sleep-disordered breathing can be one of the major determinants of high blood pressure, but there has been no study on SDB with an emphasis on shift workers. To examine the association between blood pressure and SDB among shift workers, the researchers analysed both shift and day workers in a Japanese nuclear power plant. Blood pressure levels and oxygen desaturation, which is used to assess the extent of SDB, were measured among 253 male shift workers and 206 male day workers between the ages of 30 and 62 years. It was found that the rate of SDB occurring at least 10 and at least 15 times per hour was 11 and 6 percent, respectively. There were no significant differences between shift and day workers. SDB was linked to higher blood pressure levels, primarily in older shift workers. The finding supports the notion that shift work is an independent risk factor for (high blood pressure) in older individuals who have sleep apnoea. The relationship between SDB and high blood pressure is more complicated, and work schedules need to be taken into account in both studying and treating high blood pressure and sleep apnoea.