Cardiac autonomic neuropathy associated with diabetes can cause silent myocardial ischemia and may influence the way that patients perceive symptoms of acute coronary syndromes (ACS). The purpose of this study was to examine symptoms of ACS in patients with and without diabetes while controlling for length of time with diabetes. A convenience sample of 256 patients from two large medical centers in the Midwest participated. Patients with diabetes comprised 33.2% of the sample and reported significantly less chest pain and more unusual fatigue. Patients with diabetes of longer duration (10 or more years) reported more difficulty breathing than did patients with diabetes of shorter duration (fewer than 10 years). Older patients with the same diabetes status also reported less chest pain. For older patients and for patients with diabetes, lack of chest pain during ACS could delay treatment and is thus a concern.Keywords diabetes mellitus; acute coronary syndromes; myocardial ischemia; symptoms Diabetes is the fifth-leading cause of death in the United States. Over 65% of these deaths are attributed to cardiovascular disease (American Diabetes Association, n.d.). Diabetes confers a two-to fivefold greater risk of cardiac mortality for women and a threefold greater risk of cardiac mortality for men as compared to age and sex-matched persons without diabetes (Blendea, McFarlane, Isenovic, Gick, & Sowers, 2003). Increased mortality has been linked to a greater prevalence of silent ischemia associated with diabetes (Chico, Tomas, & Novials, 2005). It has been suggested that one mechanism of silent ischemia is cardiac autonomic neuropathy (CAN), which is a form of autonomic neuropathy involving damage to autonomic fibers, innervating blood vessels and the heart (Manzella & Paolisso, 2005). This damage may affect the afferent pathways that carry pain messages from the myocardium to the cerebral cortex, leading to diminished or absent chest pain during acute coronary syndromes (ACS; Langer, Freeman, Josse, Steiner, & Armstrong, 1991). Twenty-two percent of persons with type 2 diabetes have CAN, and silent ischemia occurs more frequently with diabetes in the presence of CAN (38%) as opposed to the absence of CAN (5%; Vinik, Freeman, & Erbas, 2003). The effects of CAN are not trivial. Manzella and Paolisso (2005) reported that mortality rates are 53% for those with CAN 5 years after diagnosis.
Diabetes, CAN, and Silent Myocardial IschemiaThe consequences of silent ischemia can be grave because lack of symptoms and lack of symptom recognition can lead to delay in seeking immediate medical assistance during ACS and can be a factor in sudden cardiac death. There is limited research examining the cardiac symptoms reported by patients with diabetes who present with ACS. Funk, Naum, Milner, and Please address correspondence to Holli A. DeVon, PhD, RN; e-mail: hdevon@luc.edu. Other studies have found differences in cardiac symptoms, depending on diabetes status. Canto et al. (2000) noted that a higher proportion of patients...