Changes of Blink Reflex in Type 2 Diabetes Mellitus

Endocrine characteristics and risk factors of type 2 diabetes complicated with gastrointestinal autonomic neuropathy: A single-center retrospective study

To analyze endocrine characteristics and risk factors of type 2 diabetes mellitus (T2DM) gastrointestinal autonomic neuropathy. A total of 202 patients with T2DM with obesity who were hospitalized at our institute between January 2019 and June 2021 were selected. Based on adrenocorticotropic hormone (ACTH) levels, 102 patients were placed in the ACTH abnormal group and 100 patients were placed in the non-ACTH abnormal group. Ninety-five healthy adults without diabetes, hyperlipidemia, osteoporosis, or endocrine system abnormalities who were examined at our hospital during the same period were selected as the control group. Fasting plasma glucose (FPG), fasting insulin (FINS), triglycerides (TG), total cholesterol (TC), homeostasis model assessment of insulin resistance (HOMA-IR), ACTH level, body mass index (BMI), and bone mineral density (BMD) were measured to evaluate endocrine characteristics and risk factors. BMI, FPG, FINS, HOMA-IR, TG, TC, and ACTH levels in the abnormal ACTH group were significantly higher than those in the other 2 groups, while BMD was significantly lower than that in the other 2 groups (all P < .05). BMI, FPG, FINS, HOMA-IR, TG, TC, and ACTH in the non-ACTH abnormal group were significantly higher than those in the control group, whereas BMD was significantly lower than that in the control group (all P < .05). The plasma ACTH level in patients with abnormal ACTH levels was significantly positively correlated with BMI, FPG, FINS, HOMA-IR, TG, and TC and negatively correlated with BMD (all P < .05). Multivariate regression analysis showed that BMI, advanced age, FINS, TG, and FPG were risk factors for ACTH abnormalities in patients with diabetes (odds ratio > 1, all P < .05). BMI, advanced age, FINS, TG and FPG are the risk factors of abnormal ACTH in T2DM patients with gastrointestinal autonomic neuropathy.

Diabetes Mellitus and Bell's Palsy

The aim of the present brief review was to discuss Bell's palsy (BP) in diabetes mellitus (DM). The risk of BP is increased in DM. DM subjects with BP are more prone to severe facial nerve degeneration. Further characteristics of BP in DM include a) infrequent taste impairment; b) more frequent and more marked facial nerve subclinical electrophysiological impairment; c) more frequent Blink reflex impairment; d) potentially concurrent distal symmetrical sensorimotor polyneuropathy; e) more frequent alternating BP with recurrent episodes affecting different sides of the face. Diagnosis of BP rests on clinical examination, along with facial nerve electromyographic and electroneurographic evaluation. Management of BP in DM includes physical therapy, corticosteroids, and antiviral agents. Finally, acupuncture, low-level laser therapy, lipoprostaglandin E1, and stellate ganglion block are new modalities with initially promising results.

Patterns of facial and blink reflex abnormalities in type 2 diabetes mellitus patients with short disease duration: a clue to subclinical cranial neuropathy

Background

Cranial neuropathies occur in 3 to 14% of diabetic patients. Motor conduction study of the facial nerve and blink reflex study are electrophysiologic techniques used to assess the facio-trigeminal pathway in diabetic patients. The patterns of facial and blink reflex abnormalities are inconsistent among studies. This study aimed to assess the subclinical facial nerve and blink reflex abnormalities patterns in short-duration type 2 diabetes mellitus patients. This cross-sectional study included 30 type 2 diabetic patients with disease duration ≤ 5 years. We included only patients with the Toronto clinical neuropathy score ≤ 5. We enrolled 30 age- and sex-matched healthy subjects as a control group. We performed facial nerve motor conduction and blink reflex studies. Patients with prior history of cranial nerve lesions, stroke, or any other disease-causing polyneuropathy or drug-induced neuropathy were excluded from the study.

Results

Thirty diabetic patients were included, 20 females (66.7%) and ten males (33.3%). Their mean age was 52.63 ± 8.94 years. None of the patients had clinical evidence of neuropathy. There were significant differences between patients and controls in the distal latencies and amplitudes of facial nerve compound muscle action potentials and contralateral R2 late response latencies of the blink reflex. We detected subclinical cranial abnormalities in 6 diabetic patients (20%). One of them (3.3%) had facial nerve conduction abnormalities, four of them (13.4%) had blink reflex abnormalities, and one of them (3.3%) had both facial nerve and blink reflex abnormalities.

Conclusion

Subclinical cranial neuropathy can occur in short-duration type 2 diabetes mellitus patients. We detected different blink reflex patterns and facial conduction study abnormalities. We recommend blink reflex and facial nerve conduction studies as simple tests for the early evaluation of neurological subclinical affection in patients with short disease duration of T2DM as they may appear in the absence of peripheral neuropathy.