As optometrists, we are often asked, “What do you see in patients’ eyes?” Are the eyes truly a “window into your SOUL?” My reply is always the same, the eyes are the windows into your HEALTH. Most happy souls are healthy souls and therefore the eyes are essentially a window into your soul.
The three most frequent diseases that we look for when looking into the eyes are diabetes, high blood pressure, and high cholesterol. These three diseases are also increasingly affecting South Asians as we are finding out both clinically and in studies. In this issue, we are going to touch upon these three systemic diseases and how they affect the eyes.
Diabetes
Most recent studies have shown that individuals from South Asia have high diabetes prevalence despite low body weight. In a recent study of South Asians in California, 29% had diabetes, 37% had prediabetes and only 34% had normal glucose tolerance. Data from the Study of Health Assessment and Risk in Ethnic Groups (SHARE) confirm that Canadians of South Asian origin from urban centres have a higher prevalence of, and risk factors for, Diabetes and Cardiovascular Disease than Canadians of European and Chinese descent , with similar findings observed in South Asians living in the UK and elsewhere. Estimates of diabetes in India is currently at 12% but expected to double in this decade due to population growth and eating habits.
(LEFT) Normal Retina (CENTRE) Diabetic Patient with Vitreal hemorrhage (RIGHT) Patient with multiple dot/blot hemorrhages
Diabetes is a systemic condition where a patient has high blood sugar due to the pancreas not producing insulin (Type 1) or because cells do not respond to the insulin that is produced (Type 2) .
The most common symptoms patients face:
• Frequent Urination
• Increased Thirst
• Increased Hunger
During optometry school, my favourite professor always said to me that Diabetes is a “small vessel disease.” The big vessels of the body will generally expand to keep up with the high sugar levels and can take the abuse however the areas of the body that have small blood vessels, i.e. feet, hands and eyes, can’t do the same and thus, gets affected more than other areas affected by diabetes. Due to high sugar levels, small blood vessels in the back of the eye can burst and cause bleeding to occur in the retina. As well, fluid can leak from the blood vessels due to high sugar levels which will surely affect vision and take up to months to resolve.
High Blood Pressure
A study published in the Canadian Medical Association Journal in 2012 reports a prevalence of 23% of Canadians (26 million) in KNOWN diagnosed patients with high blood pressure. Clearly a risk factor of cardiovascular diseases, high blood pressure is another systemic disease that can manifest into eye issues. As with diabetes, fluid can leak out of blood vessels affecting critical areas of vision. As well small areas of localized bleeding can occur due to the high pressure of blood vessels present.
Changes are also seen where arteries and veins meet – another common finding in examination of high blood pressure patients. Due to the high blood pressure in the arteries, areas of the retina are affected and essentially lose supply of blood and show as white localized fluffy spots known as cotton wool spots.
According to a Statistics Canada report in 2012, around 40% of Canadians have high blood cholesterol. Us, as South Asians, have a higher risk of having high cholesterol compared to other ethnic groups. We see South Asian patients with high cholesterol frequently and we also frequently see clues to cholesterol levels in our patients through their eyes and then refer them back to their medical doctors for blood cholesterol levels.
Cholesterol changes to the eye usually occurs in the front of the eye (cornea) where a white/yellowish circular band forms usually 360 degrees around the eye right around the location where the white part of the eye meets the brown (coloured) part of the eye. This ocular finding can suggest high levels of cholesterol in the body and warrants a blood cholesterol work-up.
Arcus in Cholesterol patients
Diabetes, high blood pressure and high cholesterol continue to be the three main systemic disease that affects South Asians.
Many markers for these diseases can show up in the eyes. It is important to get eye examinations done regularly as one part of the team approach to hopefully stop or curb the rise of these diseases in our population.
By Surinder Kharé, Omni Eye & Vision