Anxiety is a ubiquitous experience. When severe, it can indicate a psychiatric problem. Various medical conditions can cause anxiety. Before concluding that anxiety stems from psychological problems, a physician should assess the patient to rule out the presence of these conditions. Anxiety is rarely the sole symptom of a severe medical condition, but it can be one of its cardinal manifestations.
Anxiety can be one of the symptoms of a heart attack. Panic attacks and heart attacks can both present with similar symptoms: anxiety, chest pain, shortness of breath, rapid heart rate and sweating. Evaluation in the emergency room is necessary to differentiate between the two. Disturbances in the heart rate rhythm can cause bouts of rapid heart rate accompanied by anxiety. As explained in "Harrison's Principles of Internal Medicine," PSVT, or paroxysmal supraventricular tachycardia, is one such rhythm disturbance. Evaluation includes a Holter monitor, which is a 24-hour electrocardiogram attached to the patient as he goes about his regular activities. The purpose is to catch a burst of abnormal rhythm that can be missed on a routine ECG.
Diseases of the lungs and airways, in which the patient can't get enough oxygen, can present with severe anxiety. Asthma and chronic obstructive pulmonary disease both cause severe anxiety as the patient struggles to get enough oxygen through airways that are not responding. Pulmonary embolism is a life-threatening condition in which a blood clot travels to the lungs and limits their ability to exchange air. Two prominent symptoms are a rapid heart rate and anxiety.
An excess of thyroid hormone causes an increased metabolic rate, and can lead to such symptoms as a rapid heart rate, weight loss and anxiety. Initial diagnosis, in addition to a medical history and physical exam, is a blood test checking the level of thyroid hormone. One cause of hyperthyroidism is Graves disease. Apart from symptoms of excess thyroid hormone, patients have bulging eyes, known as proptosis, and their eyelids are retracted, making them appear as though they're always staring.
Pheochromocytoma is a tumor that produces adrenaline independently of the body's need for it. In addition to anxiety, which usually presents as panic attacks, it can cause palpitations, headaches, sweating and high blood pressure. The anxiety attack is often accompanied by pale skin. These tumors are difficult to diagnose and require measurement of blood levels of adrenaline and related hormones, as well as imaging, such as computerized tomography and magnetic resonance imaging.
Carcinoid tumors arise from special hormone-secreting cells in the gastrointestinal tract. They secrete a wide range of hormones, including serotonin. Excess serotonin in the blood can cause carcinoid syndrome, which includes symptoms of anxiety, rapid heart rate, flushing and diarrhea. Diagnosis relies on measurement of serotonin and its metabolites in the blood.