It is National Diabetes Week so we thought we would take this opportunity to talk about the commonality of sleep apnea and type 2 diabetes. Research shows the likelihood of a relationship between sleep-disordered breathing (SDB) and type 2 diabetes, particularly with the most common form of SDB, obstructive sleep apnea (OSA). Whilst the exact nature of the relationship between the two conditions remains uncertain, the association between them has important implications for public health and for individuals. Additionally, both type 2 diabetes and SDB are strongly associated with cardiovascular disease (CVD). SDB is increasingly considered as a condition to be treated for the prevention of CVD. When type 2 diabetes is already present, the treatment of SDB is even more relevant, because people with diabetes are already at high risk of CVD. While the enormity of the type 2 diabetes epidemic is well recognised, disorders of breathing during sleep are not. However, they make a significant contribution to the burden of disease in individuals and the financial burden on communities.
Extent of the problem
The number of people with type 2 diabetes worldwide is set to increase from its present level of over 250 million to 380 million by 2025. Approximately seven million people develop it every year and almost four million die of its consequences every year. CVD is the major cause of death in diabetes, accounting for some 50% of all diabetes fatalities, and much disability. People with type 2 diabetes are over twice as likely to have a heart attack or stroke as people who do not have diabetes.
OSA is the most common form of SDB. It is often present among people with type 2 diabetes, CVD or obesity. OSA has been noted in up to 9% of women and 24% of men however after menopause women are just as likely as men to have OSA. Risk factors include being male, overweight, and over the age of forty, but sleep apnea can strike anyone of any weight and at any age, even children (OSA has also been noted in as many as 6% of children). Yet because of the lack of awareness by the public and healthcare professionals, many people remain undiagnosed and therefore untreated.
Untreated, sleep apnea can cause high blood pressure and other cardiovascular diseases, memory problems, weight gain, impotence, and headaches. Moreover, untreated sleep apnea may be responsible for workplace problems and car accidents. While the exact medical costs of untreated sleep apnea in Australia are not known, the medical costs of untreated OSA in the United States are estimated at $3.4 billion US per year, but the total economic impact of OSA is far greater due to indirect costs such as loss of productivity, accidents, and disability.
While there is no strong evidence to suggest OSA causes type 2 diabetes there is increasing evidence that OSA is associated with type 2 diabetes and with CVD. It is likely that more than half of the people with type 2 diabetes suffer from some form of sleep disturbances and that as many as 48% of people with type 2 diabetes have OSA. This rises to up to 58% in the older type 2 diabetes population and is as high as 86% in obese populations with type 2 diabetes. Conversely, estimates suggest that up to 40% of people with OSA will have diabetes. OSA is also known to be a risk factor for the development of hypertension. It has been shown that people with mild to moderate OSA are twice as likely to develop hypertension as are people without OSA. Additionally, OSA has been shown to increase the risks of heart attacks and stroke.
So having OSA doesn’t mean you’ll get type 2 diabetes or vice versa. However, considering the significant overlap between these two conditions, it is reasonable to suspect that if you do have one of these conditions, your likelihood of developing the other is increased.
That means paying extra close attention to the risk factors for type 2 diabetes if you have sleep apnea and making sure you’re doing all you can to ensure healthy sleep if you happen to have type 2 diabetes. If you are a loud snorer and/or suffer any of the signs and symptoms of OSA mentioned below speak to your GP.
What is Obstructive Sleep Apnea?
Sleep apnea is a sleep disorder characterised by pauses in breathing during sleep caused by a physical block to airflow. There are two forms of sleep apnea, obstructive apnea and central apnea. OSA is much more common and is the result of obstruction of the airway leading from the nose or mouth to the lungs. The obstruction is usually the result of a narrowed airway which becomes partly or completely blocked when the muscles around the airway relax during sleep. Central apnea is rare and results when the signals from the brain to regulate breathing are disrupted in some way. OSA occurs two to three times more often in older adults and is twice as common in men as in women however after menopause women are just as likely as men to have OSA. Children can also have OSA.
Classic signs and symptoms of sleep apnea include:
• Excessive daytime sleepiness
• Loud snoring
• Snorting and gasping during sleep
• Dry mouth and morning headaches
• Poor concentration and attention
• Memory problems
• Sexual dysfunction
• Nocturia (frequent urination at night)
The person with sleep apnea is rarely aware of the difficulties they have of breathing during sleep, therefore sleep apnea often goes undiagnosed. Sleep apnea is typically noticed by others who witness the pauses in breathing, gasping for air, and loud snoring. People with sleep apnea may also not notice the excessive daytime sleepiness and fatigue that they experience caused by the extremely fragmented and/or of poor quality sleep because it can be something that they become used to.
Type 2 Diabetes
Type 2 diabetes is a progressive condition in which the body becomes resistant to the normal effects of insulin and/or gradually loses the capacity to produce enough insulin in the pancreas. Type 2 diabetes can remain undetected for many years, as it is often asymptomatic. Its diagnosis is often made from associated complications such as a heart attack, vision problems, or a foot ulcer or incidentally through an abnormal blood or urine glucose test. Type 2 diabetes is often, but not always, associated with excess weight and is most common in people older than 45 who are overweight. However, as a consequence of increased obesity among the young, it is becoming more common in children and young adults. Although type 2 diabetes is also linked to ethnicity and genetic factors, obesity, physical inactivity, and unhealthy diet increase the risks. Type 2 diabetes is the most common form of diabetes accounting for 85 to 95% of all diabetes. If people with type 2 diabetes are not diagnosed and treated, they can develop serious complications, which can result in severe disability and early death. "Type 2 diabetes is a preventable dietary disease. People don't need to die - they don't even need to develop type 2 diabetes.” - Australian of the year 2020 Dr James Muecke AM.
So what is it about our diet that causes so many preventable deaths and 250 Australians to develop type 2 diabetes EVERY DAY? Dr Muecke AM discusses what he thinks is contributing to the problem here > https://www.canberratimes.com.au/story/6827184/dietary-advice-weve-been-fed-for-decades-is-wrong References: Shaw JE, Punjabi NM, Wilding JP, Alberti KGMM, Zimmet PZ. Sleep-Disordered Breathing and Type 2 Diabetes. Diabetes Res Clinical Pract 81(1), 2008
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