Peripheral Neuropathy and Cardiac Autonomic Neuropathy among Type II Diabetic Patients: Prevalence and Risk Factors

Background: The two most common chronic complication softype 2 diabetes mellitus (T2DM) are peripheral neuropathy (PN) and Cardiac autonomic neuropathy (CAN).Diagnosing neuropathies at subclinical stage can prevent the morbidity and mortality. Objectives: To determine the prevalence of peripheral neuropathy and cardiovascular autonomic neuropathy and their risk factors in type-II diabetic patients attending a tertiary care hospital. Methods: An observational cross sectional study was done from December 2019 to November 2020 in the department of General medicine at tertiary care hospital. 273 type II diabetic patients were selected for this study. Toronto clinical scoring system was used for assessing PN and ewings cardiovascular reflex study was used done to assess CAN. To identify the risk factors of PN and CAN, Logistic regression analysis was used. Results: The prevalence of PN and CAN was 45.4% and 34.06% respectively, while29.3% participants had both. Smoking (OR: 12.976; 95% CI: 0.052–0.418, P<0.0001) and poor glycaemic control (OR: 27.231; 95% CI: 5.226–38.201, P<0.0001) were independent risk factors of DPN. Original Research Article Surendra et al.; JPRI, 33(39B): 103-110, 2021; Article no.JPRI.71802 104 poorglycaemic control (OR: 26.970; 95% CI: 3.507–16.055, P <0.0001) and Dyslipidimea (OR: 11.792; 95% CI: 0.096–0.526, P ≤ 0.001) were independent predictors of CAN. Interpretation and Conclusions: PN and CAN are common among diabetic patients, and thus it is recommended to screen Peripheral Neuropathy and CAN in all diabetic patients for the early diagnosis and preventing the debilitating complications


INTRODUCTION
Diabetic Neuropathy (DN) is the major cause for hospitalization than other complications of diabetes and is also the most common cause for non-traumatic amputation and autonomic failure [1,2] and thus causing negative effect significantly on quality of life of patientswithT2DM [3] There are 4 different types of neuropathy: peripheral neuropathy, proximal neuropathy, autonomic neuropathy & focal neuropathy. In peripheral neuropathy the symptoms varies from severely painful at one extreme to the completely painless and the patients having damage to the nerves looses the ability to perceive the sensations like heat, cold and pain in extremities and thus Peripheral Neuropathy participates in causing foot ulceration [4].
In CAN, parasympathetic and sympathetic functions are altered, but still these dysfunctions are masked for longtime. CAN is identified at later stages as autonomic system can react to both internal environment stress and external environment stress [5]. CAN is one of the leading cause of increasing incidence of silent myocardial ischemia and sudden death is in T2DM patients [6][7].
Early screening, appropriate intervention and treatment of Peripheral neuropathy and CAN in T2DM are very important as these two neuropathies are masked and neglected at subclinical stage and ultimately leading to debilitating complications.
The present study was planned to determine the prevalence and risk factors of peripheral neuropathy, Cardiac autonomic neuropathy (CAN) among type-II Diabetes Mellitus participants in a tertiary care hospital. Hypertension: blood pressure of the participants was measured in the right arm using mercury column sphygmomanometer after patient had adequately rest and seated and considered to be hypertensive if SBP ≥140 mm Hg or DBP ≥ 90mm Hg or taking anti hypertensive drugs [9].

MATERIALS AND METHODS
Biochemical analysis: Five milliliters of venous bloods was drawn under aseptic conditions for serum glycosylated haemoglobin (HB), serum triglycerides& Cholesterol.
Diabetic peripheral neuropathy: TCSS Scale was used for screening DPN among type-II diabetic patients. Scoring was given for symptoms, sensory tests & reflexes. Based on the abnormalities, for symptoms and sensory tests, a point of 0 or 1 was given and for reflexesa point of 0, 1 or 2 was given. Total score ranges from 0 to 19. Finally, for Symptoms 6 points were given, for sensory examination 5 points were given and for lower limb reflexes, 8 points were given. Components of the scale are: Foot symptoms scores-Pain, Numbness, Tingling, Weakness and Ataxia. Upper-limb symptoms, sensory testing-Pinprick, Temperature, Light touch, Vibration and Position and reflexes-Knee reflexes and Ankle reflexes Severity of neuropathy was classified based on the score as: Score of 0-5= no peripheral neuropathy; 6-8= mild PN; 9-11= moderate PN; 12-19= severe [14].

Ewings Cardiovascular Reflex Tests (CRT):
All the patients selected for study underwent Cardiovascular Reflex Tests (CRT) for evaluation of Cardiac autonomic neuropathy. Standard

RESULTS
The characteristics of the study participants were described in Table 1.
The tests of diabetic peripheral neuropathy and cardiac autonomic neuropathy were described in Table 2.
Factors associated with Diabetic peripheral Neuropathy on multivariate analysis were described in Table 3.
Factors associated with cardiac autonomic neuropathy on multivariate analysis were described in Table 4.

DISCUSSION
This study estimated the prevalence and risk factors of peripheral neuropathy and CAN among type II diabetic patients attending a tertiary care

CONCLUSION
This study showed that PN and CAN are quite common among diabetic patients and with about one in four patients having a mixed form of the two. In the regular examination of Type 2 Diabetes Mellitus patients, these simple noninvasive tests for Peripheral Neuropathy and Cardiac autonomic neuropathy can be incorporated for the early diagnosis of peripheral neuropathy and cardiac autonomic neuropathy to prevent the complications.

DISCLAIMER
The products used for this research are commonly and predominantly use products in our area of research and country. There is absolutely no conflict of interest between the authors and producers of the products because we do not intend to use these products as an avenue for any litigation but for the advancement of knowledge. Also, the research was not funded by the producing company rather it was funded by personal efforts of the authors.

CONSENT AND ETHICAL APPROVAL
Institutional ethics committee approval was taken for conducting the study and written & informed consent form was taken from all the participants.