Respiration problems in sleep apnea - which causes people to momentarily stop breathing multiple times throughout the night, for seconds to minutes at a time - appear to worsen during the colder months of the year, according to a study from Brazil.
Changes in weight and seasonal allergies can affect sleep apnea, and researchers writing in the journal Chest wanted to see if weather changes might also have an impact.
"More sleep disordered breathing events were recorded in wintertime than in other seasons," wrote study leader Cristiane Maria Cassol from the Universidade Federal do Rio Grande do Sul.
Cassol and her team said it could be due to several causes, including winter-related upper-airway problems that intensify the severity of symptoms and the use of burning wood to heat homes during the winter.
The team utilized data from sleep clinic patients and looked at how many times their rest was disturbed by breaks in breathing. The study included one night of sleep for more than 7,500 patients over a 10-year-period.
Researchers then compared the severity of the patients' apnea to the weather conditions at the time, including humidity, temperature and air pollution.
Patients who came in during colder months had more nighttime breaks in breathing than those who sought treatment during warmer months. During the winter, patients stopped breathing an average of 18 times an hour compared to 15 times an hour during the summer.
Similarly, the sleep clinic was more likely to see the most severe cases - people who stopped breathing more than 30 times an hour - during the colder months.
About 34 percent of patients who came in during cold weather had severe apnea, compared to 28 percent of patients during warmer weather.
The team found that certain weather conditions, such as high atmospheric pressure and humidity and high levels of the air pollutant carbon monoxide - were tied to worse cases of apnea.
But the study could not determine whether it was the weather itself that was responsible for the more severe apneas.
Jerome Dempsey, who studies breathing problems at the University of Wisconsin and wasn't involved in the study, said it makes sense that airway infections and weather could have an effect on sleep apnea, but that the changes across the seasons were small.
"There are so many things that affect sleep apnea, including the decision of when to come visit" a sleep clinic, Dempsey told Reuters Health.
In other words, it might not be the weather but the time of year that makes it more convenient for patients to take the time to seek treatment.
He added that while winter-related conditions such as colds or allergies might intensify sleep apnea, the biggest risk factor is obesity. SOURCE: http://bit.ly/MqNmmE
The reason for the high-level threat in the area is the presence there of Aedes aegypti mosquitoes, which carry the Zika virus that health authorities say causes birth defects in newborns
Three-day African Utility Week conference begins in South African city of Cape Town
More than two thousand activists came together to close an opencast coal mine in Germany.
New federal rules unveiled on Thursday will tackle the release of the greenhouse gas methane from oil wells and equipment as part of an effort to fight climate change.
At least five reef islands in the remote Solomon Islands have been lost completely to sea level rise and coastal erosion
Heads of UN, Work Bank lay out vision to deal with climate change
Turkish environment minister signs historic agreement in New York against taking action against climate change
Human defense mechanisms could be disrupted by the presence of a class of organic pollutants in fish and other food, according to new research.
'The time has come to treat childhood stunting as a development and an economic emergency,' World Bank Group head says
Obese population hits all-time high with a new studying finding that obesity can be predicted in babies
New research factors in collapsing Antarctic ice sheet that could double the sea-level rise to two metres by 2100 if emissions are not cut
Temperatures in the first two months of 2016 followed a year that broke 'all previous records by a wide margin'
Researchers at MIT may have made an important breakthrough in the fight against Alzheimer’s Disease.
Human immune system could be steered towards fighting cancerous tumors, researchers find
Data released on UN world wildlife day shows overall population is still falling despite a recent reduction in levels of poaching for ivory
Google will donate $1mn to help UNICEF map Zika outbreaks