Protect your brain with optimal glucose control
Four hundred South Africans suffer a stroke daily: this is a medical emergency where the blood flow to a section of the brain is interrupted or diminished. What’s important is prompt treatment, which can limit damage to tissue that’s suffered a lack of oxygen and nutrients. Dr Rudi Renison, a neurologist in private practice at Mediclinic Cape Gate, explains.
A recent local study, The prevalence of type 2 diabetes in South Africa: a systematic review protocol, published in the latest British Medical Journal (BMJ), reveals that 10% of all ischaemic strokes – those caused by a blocked artery – suffered in the country can be attributed to diabetes. This is because, in poorly-controlled diabetes, high levels of glucose over the years can cause damage to blood vessels, hardening and narrowing them with fatty deposits – a condition called atherosclerosis.
“Poor glucose control significantly correlates with brain atrophy … leading to complications such as ischaemic stroke,” says Dr Renison. He explains that obesity-associated diseases, such as type 2 diabetes and hypertension, have significant vascular risk factors.
Unfortunately, the BMJ study reveals that the prevalence of this lifestyle disease is increasing rapidly in South Africa, associated with an ageing population, economic transition and urbanisation. But: 87% of cases of the illness can be attributed to excess body weight, and 38% of men and 69% of women in South Africa were considered overweight or obese in 2013. Additionally, the 2015 Global Burden of Disease study has estimated that high body mass index and hyperglycaemia rank second and third, after unsafe sex, as the leading risk factors for early death and disability in South Africa.
Know the signs
As Dr Renison explains, “The exact ways obesity can lead to brain atrophy and impaired cognitive function are complex and multi-factoral, ranging from systemic and central chronic low-grade inflammation, insulin resistance, type 2 diabetes, hypertension, microvascular and macrovascular ischaemic brain changes, sleep apnoea and complex genetic factors.”
He adds that while adipocytes produce inflammatory cytokines leading to inflammation and a reduction in brain size, the insulin resistance that commonly accompanies obesity impairs the brain due to its vasoactive effects on cerebral arteries. The changes it makes to the nervous system can result in similar pathology to Alzheimer’s disease.
Because diabetic patients are 1.5 times more likely to suffer an ischaemic stroke than those without the condition, it is vital that such individuals familiarise themselves with the symptoms of stroke (see sidebar below*), while family and friends memorise the FAST test, i.e.:
If you suspect a stroke, ask the person to:
[F]ace: Smile or show their teeth. Does one side droop?
[A]rm: Raise both arms. Does one arm drift down?
[S]peech: Repeat a sentence. Are they battling to speak or understand you?
[T]ime: Time saved is brain function saved. Every minute counts in accessing care.
Symptoms of stroke
• severe headache without cause
• dizziness and trouble walking/balancing
• loss of vision in one/both eyes
• difficulty speaking or understanding others
• numbness/weakness in the face, arm or leg, especially on one side
Hope is at hand
Due to recent medical advances, ischaemic strokes can usually be successfully treated when help is sought immediately – either with medication to dissolve the clot or by the insertion, of a tiny clot-extracting instrument into the affected artery by a neurologist.
While the best thing to do is ensure that your type 2 diabetes is well controlled by systematically following your doctor’s recommended treatment protocol, research also suggests that the negative effects of obesity and hyperglycaemia on the brain can also be reversed. As Dr Renison explains, losing weight, eating a healthy, balanced diet, exercising (regularly) and not smoking are safeguards that can hopefully ensure you never become a stroke victim in the first place.