Diabetic patients are at a higher risk for heart attacks than people with normal blood sugars. Several factors play a role in this heightened diabetic risk profile, including insulin resistance, enhanced clotting tendencies, high blood pressure, elevated lipid levels and a predisposition to heart muscle abnormalities --- all raising the risk of cardiac problems. It is therefore essential for diabetics to recognize the symptoms of a heart attack.
Classic Symptoms
Crushing chest pain can be a symptom of a heart attack in persons with or without diabetes. Also known as a myocardial infarction or MI, a heart attack can cause severe chest pain that should prompt a person to seek immediate medical attention, particularly if it is accompanied by pain in the arm or neck, sweating or lightheadedness. Diabetics can experience these same classic symptoms during an MI, but they cannot rely on them. According to studies published in "Diabetologia" and the "Journal of the American College of Cardiology," diabetics are at a much higher risk of experiencing a "silent" heart attack, an attack that has few noticeable symptoms.
Angina
When a person's heart is deprived of adequate blood flow for any length of time, it sends signals to the brain that are interpreted as pain. This discomfort, called angina, is typically located in the left front part of the chest, but it can also be felt in the back, the upper abdomen, the arms or shoulders, the neck or the jaw. For reasons that are not entirely understood, diabetics -- if they experience pain at all -- are more likely to feel angina in unusual places.
Breathlessness
The heart pumps oxygen-rich blood to every cell and organ in the body. During an MI, the heart's own blood flow is interrupted, its contractions weaken and its efficiency declines. This leads to a fall in cardiac output and a generalized loss of oxygen delivery. This whole-body and organ-specific oxygen deficit is frequently manifested by "air hunger" and a rapid respiratory rate. Unusual fatigue, however, may be the only symptom of a compromised heart.
Sweating
The heart is connected to the brain and spinal cord through a network of nerves. During a heart attack, nerve impulses from the heart stimulate the parasympathetic and sympathetic nervous systems as well as the central nervous system. This burst of neuronal activity can lead to sweating, nausea, a sudden drop in blood pressure and dizziness.
Confusion
Since the brain cannot function well without a continuous oxygen supply, a drop in blood delivery from the heart interferes with normal brain activity. This can result in confusion, disorientation, agitation or even a loss of consciousness. Whenever a diabetic's mental status changes suddenly, a cardiac problem could be one cause.
Palpitations
If an area of heart muscle receives too little oxygen, it can become "irritable." This irritable area may generate electrical impulses which are not synchronized with the remainder of the heart, and eventually the entire heart's rhythm can be disrupted. An irregular, pounding or unusually rapid heartbeat, known as palpitations, may be the first sign of a heart attack for some individuals. Some of these dysrhythmias, as they are called by physicians, can be lethal if they are not treated.
Special Considerations
Because many of the signs and symptoms of poorly controlled diabetes mimic those of a heart attack, diabetics are at particular risk of delaying medical care while they try to sort things out. A confused, sweaty diabetic, for example, may be suffering from low blood glucose as a result of taking a medication and then missing a meal, or these problems may be related to an ongoing heart attack. Diabetics should remain vigilant for new symptoms and should seek help if an explanation for those symptoms is not rapidly forthcoming.
References
- "Hypertension"; Diabetes, Hypertension, and Cardiovascular Disease: An Update
- "Diabetologia"; Silent myocardial infarction and its prognosis in a community-based cohort of Type 2 diabetic patients: the Fremantle Diabetes Study
- "Journal of the American College of Cardiology"; Significance of silent ischemia and microalbuminuria in predicting coronary events in asymptomatic patients with type 2 diabetes
