To study the impact of glycemic control over cardiac autonomic neuropathy in type 1 and type 2 diabetics patients using bedside tests at a tertiary care hospital

Sumaiya Anjum, Suresh K.


Background: Cardiac autonomic neuropathy a serious complication of diabetes and is often overlooked. It is associated with higher cardiovascular mortality and poor quality of life in diabetic individuals. The Glycemic control has been well established as the risk factor for all the diabetes related microvascular and macrovascular complications. This stresses importance of role of glycemic control over CAN in Type 1 and Type 2 Diabetics in order to stop further progression to advanced and irreversible stages. The objective was to study the impact of various demographic and other clinical factors over prevalence of CAN in type 1 and type 2 diabetic patients who are asymptomatic for CAN using bedside tests

Methods: A case control comparative clinical study was undertaken comprising of 100 diabetic patients, both type 1 and type 2 with duration from 5-10 years and >10 years. The tests which were performed are deep breathing test, heart rate response to standing, hand grip test, cold pressor test, BP response to standing. Depending on these tests, patients were categorised as patients with cardiac autonomic neuropathy and without cardiac autonomic neuropathy.

Results: The prevalence of cardiac dysautonomia was 68%. Type 2 diabetics had higher prevalence of cardiac dysautonomia than type 1 diabetics (p=0.025). Significant correlation was observed between cardiac autonomic neuropathy and poor glycemic status (type 1 p<0.001; type 2 p<0.001). The mean HbA1c in patients with and without CAN in type 1DM was 9.16+0.81 and 7.21+0.56 and in type 2 DM was 9.15+1.72 and 7.15+0.53 respectively. Similarly, presence of other microvascular complications increased the prevalence of CAN in both types of diabetes mellitus.

Conclusions: Cardiac autonomic neuropathy is a common complication in long standing diabetes. Present results suggest that glycemic status of the diabetics is undoubtedly an important factor for the onset of cardiac dysautonomia which in turn account for high prevalence of cardiac mortality in diabetic patients. All asymptomatic diabetic patients should be evaluated for the presence of autonomic neuropathy and glycemic status should be controlled to prevent the further progression of CAN.


Autonomic Function test, Autonomic neuropathy, Cardiac dysautonomia, Glycemic control, Prevalence, Type 1 Diabetes mellitus, Type 2 Diabetes mellitus

Full Text:



Powers AC. Diabetes mellitus. In: Braunwald, Fauci, Hauses, Longo, Jameson, eds. Harrison’s Principles of internal medicine. 17th ed. Philadelphia, PA: McGraw-Hill. 2008;2:2275.

Das AK, Rai M. A world without diabetes and its complications: A preventive program. In: Jayaram BM, ed. Type 2 Diabetes and its complications: A preventive program, Bangalore: Micro Labs Limited; 2008:1.

Pagkalos M, Koutlianos N, Kouidi E, Pagkalos E, Mandroukas K, Deligiannis A. Heart rate variability modifications following exercise training in Type 2 diabetic patients is definite cardiac autonomic neuropathy. BJSM. 2008;42;47-54.

Vinik AI, Freeman R, Erbas T. Diabetic autonomic neuropathy. Semin Neurol. 2003;23(4):365-72.

Sztajzel J. Heart rate variability: A noninvasive electrocardiographic method to measure autonomic nervous system. Swiss Med Wkly. 2004;134:514-22.

Vink IA, Maser ER, Mitchell DB, Freeman B. DAN. Diabetes Care. 2003;26(5):1553-79.

Maser RE, Lenhard MJ. Cardiovascular autonomic neuropathy due to diabetes mellitus: clinical manifestations, consequences, and treatment: review. J Clin Endocrinol Metab. 2005;90(10):5896-903.

Khandelwal E, Jaryal AK, Deepak KK. Pattern and prevalence of cardiovascular autonomic neuropathy in diabetics visiting a tertiary care referral center in India. Indian J Physiol Pharmacol. 2011;55(2):119-27.

Kempler P, Tesfaye S, Chaturvedi N, Stevenst LK, Webbt DJ, Eaton S, et al. Autonomic neuropathy is associated with increased cardiovascular risk factors: the EURODIAB IDDM complications study. Dai Med. 2002;19:900-9.

Khoharo HK, Ansari S, Shaikh IA, Qureshi F. Cardiac autonomic neuropathy (CAN) in type 1 diabetes mellitus patients and its association with the duration of disease and glycemic control. Je Coll Phys Surg Pak. 2009;19(4):232-5.

Chen HT, Lin HD, Won JGS, Lee CH, Wue SC, Lin JD, et al. Cardiovascular autonomic neuropathy, autonomic symptoms and diabetic complications in 674 type 2 diabetes. Dia Res Clin Pract. 2008;82:282-90.

Aggarwal S, Tonpay PS, Trikha S, Bansal A. Prevalence of autonomic neuropathy in diabetes mellitus. Curr Neurobiol. 2011;2(2):101-5.