Chronic Disease and Healthy Sight

Chronic diseases, both ocular and systemic, can impact significantly on Healthy Sight. Either the disease itself or medications used to treat the disease may be responsible. An important example is diabetes mellitus. Diabetes can affect both the quantity and the quality of vision. Decreased contrast sensitivity and increased glare sensitivity are common problems in the diabetic eye. Broad fluctuations in blood sugar levels, not infrequently occurring in the person with undiagnosed diabetes, can affect quantity of vision and produce troublesome changes in refractive error. In fact, many new cases of diabetes are noticed first by the vision care professional based on unexplained refractive shifts. This is important since it has been estimated that up to 50% of persons with diabetes are unaware that they have the disease. Even more important is the finding that in 20% of newly diagnosed diabetes, diabetic retinopathy is already present at the time of diagnosis.

As diabetes progresses, the vision care professional continues to play an important role. The eye is one of the most important target organs for complications of diabetes. An estimated 40% of persons with diabetes will develop vision-threatening retinopathy as a consequence of their disease. While there are specific therapies for diabetic retinopathy when it occurs, the best treatment for diabetic eye disease is prompt and effective treatment for diabetes, the systemic disease. Prevention is, of course, the best treatment, and weight loss, exercise, and dietary glycemic control can prevent or reverse diabetes in many individuals. Otherwise strict maintenance of hemoglobin A1C levels is the best indicator of diabetic control, both ocular and systemic. A 1% decrease in A1C level decreases the risk of development of diabetic retinopathy by 21% and decreases the risk of progression of the retinopathy by 43%. This decrease has similar effects on other important target organs for diabetes, such as the kidneys.

Clearly factors contributing to overall health including diet, exercise, and lifestyle play a critical role in ocular health and this is especially true in diabetes. Excessive caloric intake, a carbohydrate-rich diet, insufficient exercise, and smoking are all risk factors for diabetes, the systemic disease, as well as diabetes, the ocular disease.

While diabetes is an important example, there are many other chronic diseases that may significantly impact Healthy Sight, including autoimmune disorders, asthma, cancer, cardiovascular disease, hypertension, endocrinopathies, and circulatory disturbances. For each of these chronic diseases, lifestyle modifications including maintenance of a normal weight, a healthy diet, a regular program of exercise, and avoidance of such risk factors as smoking and excessive alcohol consumption can significantly reduce risk.

There is one additional area where the relationship between risk factors for chronic disease and Healthy Sight is relevant; this is in the area of ultraviolet radiation (UVR) exposure. The relationship between the development of photoaging and cutaneous neoplasia and UVR exposure is well-recognized. Less commonly recognized, however, is the relationship between UVR exposure and such vision-threatening ocular diseases as cataract and age-related macular degeneration (AMD). In fact, in a number of recent surveys, it has been convincingly shown that while the vast majority of people worldwide are aware of the risk of UVR exposure to the skin, only a small minority are aware of the risk posed by UVR to the eye. Avoidance of UVR exposure and the proper and consistent use of protective eyewear that effectively blocks 100% of UVA and UVB can help to decrease this risk. The customized eyeglass prescription, so integral to the practice of Healthy Sight Counseling, stresses the importance of ocular UVR protection in eyewear.

Effective Healthy Sight Counseling goes beyond promoting Healthy Sight, recognizing the intimate relationship between ocular and systemic health and setting as its goal both Healthy Sight and a Healthy Life, since achieving one is often dependent upon achieving the other.

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