Diabetes and High Blood Pressure Have Common Risk Factors
Both diabetes and high blood pressure tend to share many predisposing factors. The same set of criteria that puts one at risk for developing high blood pressure also contributes to the development of diabetes. High-fat diets rich in salt and processed sugars put stress on both enzyme production and the cardiovascular systems. Low levels of physical activity decrease the efficiency of insulin and also lead to stiff arteries and a poorly responsive cardiovascular system. Excess body weight has similar consequences, and is a strong risk factor for both diabetes and high blood pressure.
Diabetes and High Blood Pressure Affect Similar Patients
Just as diseases can share risk factors, risk factors can share patients. Diabetes and high blood pressure can be thought of as “patient sharing” diseases - each disease tends to affect patients who are already at risk for the other. This is similar to the idea of shared risk factors, but is a more subtle point. As an example of this point, data has shown that people who smoke more than a pack of cigarettes a day are more likely to drink alcoholic beverages than those who do not smoke. Though “cigarettes” and “alcohol” have nothing in common, “smoking” and “drinking” do. Likewise, people who engage in lifestyles that predispose them to diabetes also tend to follow patterns that put them at risk for high blood pressure.
Diabetes and High Blood Pressure are Self-Reinforcing
Patients with diabetes have elevated blood sugar compared to patients without diabetes. This excess sugar has many consequences, including slow but serious damage to sensitive blood vessels called capillaries. Damage to certain capillaries in the kidneys impairs the kidney’s blood pressure regulating abilities, leading to higher blood pressure. This increased blood pressure causes small changes in blood flow, which exposes other sensitive capillaries to additional damage. Elevated blood pressure can also affect the delicate insulin secreting areas of the pancreas, leading to higher blood sugar. In this way, the diabetes/high blood pressure combination is a self-reinforcing loop in which both diseases tend to worsen over time.
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