IF type 2 diabetes is not well managed – patients are at greater risk of going blind. However, now experts have found there is also a risk among people with diabetes who also suffer with obstructive sleep apnoea.
Obstructive sleep apnoea (OSA) is a condition where the walls of the throat relax and narrow during sleep, resulting in snoring and interrupting breathing, and it is common in patients with Type 2 diabetes.
Diabetic retinopathy – the most common form of diabetic eye disease – affects between 40 and 50 per cent of patients with diabetes and is a leading cause of blindness.
The research was led by the University of Birmingham.
“Despite improvements in glucose, blood pressure and lipid levels, diabetic retinopathy remains very common,” said Dr Abd Tahrani, of the University of Birmingham’s Institute of Metabolism and Systems Research.
“Meanwhile, OSA has been shown to be very common in patients with Type 2 diabetes, which is not surprising considering that excess weight contributes to the development of both of these conditions.
“However, most patients who have OSA are not aware that they have the condition and the disease could go undiagnosed for years.
“Firstly, we showed that sight-threatening diabetic retinopathy was more common in patients with both yype 2 diabetes and OSA compared to those with Type 2 diabetes but without OSA.
“However, more importantly, we have shown that patients with OSA and Type 2 diabetes, compared to those with diabetes only, are at increased risk of developing advanced diabetic retinopathy over a period of three years and seven months.”
The study was carried out at two diabetes clinics at hospitals in the Midlands and involved 230 patients with type 2 diabetes.
It excluded any patients who were already known to have OSA or any kind of respiratory condition.
The patients were assessed for diabetic retinopathy and OSA.
he results showed that there were more cases of diabetic retinopathy among patients with OSA – 42.9 per cent – compared to those without OSA – 24.1 per cent.
The study found that at a follow-up appointment, on average 43 months later, the patients with OSA – 18.4 per cent – were more likely to develop moderate to severe diabetic retinopathy compared to those without OSA – 6.1 per cent.
Dr Tahrani said: “We can conclude from this study that OSA is an independent predictor for the progression to moderate or severe diabetic retinopathy in patients with Type 2 diabetes.”
He said the finding were important because it could speed up treatments for diabetic retinopathy.
“Following our research, it is important that clinicians treating patients with Type 2 diabetes are aware that their patients who also have OSA are particularly at increased risk of developing advance retinopathy and, hence, appropriate preventative measures should be put in place,” he said.
“Clinicians should consider testing patients for OSA as OSA is very common in patients with Type 2 diabetes.”
The study was published in the American Journal of Respiratory and Critical Care Medicine.