Strong snoring, sleep apnea related to earlier decline in cognition

Strong snoring, sleep apnea related to earlier decline in cognition

Breathing issues during sleep – such as excessive snoring and sleep apnea – can be linked with earlier memory and cognitive skills decline. This is the result of a 2015 study that was published in Neurology.

A man snoring
Compared with participants who were free of sleep-breathing problems – such as heavy snoring and sleep apnea – those with such problems were diagnosed with mild cognitive impairment more than 10 years earlier.

But, there’s good news. The study, conducted by Dr. Ricardo Osorio of the NYU Langone Medical Center in New York, NY and colleagues, also indicates that the continuous positive airway pressure (CPAP) treatment of these irregular breathing habits will reduce cognitive decline.

About 18 million people in the US suffer from sleep apnea – a condition in which breathing stops periodically during sleep. Around 90 million Americans are snorers, with about 37 million regularly snoring. About 50 percent of heavy snorers have sleep apnea.

Abnormal breathing habits, such as sleep apnea and heavy snoring during sleep, are more common as we age. Such breathing disorders affect approximately 52 percent of older men and 26 percent of older women, according to Dr. Osorio.

Dr. Osorio and colleagues set out on their research to see if cognitive impairment was associated with breathing difficulties during sleep-something that is often more normal as we age.

MCI diagnosed more than 10 years earlier for those with sleep-breathing problems

The team studied the medical history of 2,470 people aged 55 to 90 years, before splitting them into three groups: those with Alzheimer’s disease, those with moderate cognitive impairment (MCI), and those without memory or thinking problems.

As well as determining the existence of any breathing difficulties among the participants during sleep, the researchers investigated whether the subjects were receiving care for these issues.

According to the study, those with these issues were diagnosed with MCI much earlier compared to the participants who were free from sleep-breathing problems.

Participants with sleep-breathing problems were diagnosed with MCI at an average age of 77, while participants were diagnosed with MCI at an average age of 90 with no sleep-breathing problems.

Moreover, the researchers found that participants with sleep-breathing issues were likely to be diagnosed with Alzheimer’s at an average age of 83, while those without sleep-breathing problems acquired the condition at an average age of 88 years later.

Could CPAP prevent or delay cognitive decline?

The study, however, found that CPAP treatment – a mask worn over the nose during sleep that delivers a constant stream of pressurized air through the throat of patients – reversed the correlation between sleep-breathing issues and earlier cognitive loss.

Participants with sleep-breathing problems who received CPAP were diagnosed with MCI an average of 10 years later than those with sleep-breathing problems who were not treated with CPAP.

Commenting on their findings, Dr. Osorio says:

“The age of onset of MCI for people whose breathing problems were treated was almost identical to that of people who did not have any breathing problems at all.

Given that so many older adults have sleep-breathing problems, these results are exciting – we need to examine whether using CPAP could possibly help prevent or delay memory and thinking problems.”

He states that the team is unable to establish a cause-and-effect relationship between CPAP therapy and delayed cognitive decline, as this research is observational.

“However,” adds Dr. Osorio, “we are now concentrating our work on CPAP therapy and memory and thought loss over decades, as well as directly looking at indicators of brain cell death and deterioration.”