Sensory network dysregulation in type 2 diabetes: Linking olfactory, visual, and cognitive function.

The World Health Organisation estimated that in the year 2000, 150 million people had diabetes mellitus, and it is predicted that this number will rise to 366 million by the year 2030.[1][1] Neuropathy is a common complication of diabetes and is characterised by a progressive loss of peripheral

Objective To observe the effect of alpha lipoic acid on quality of life in patients with type 2 diabetic peripheral neuropathy. Methods 76 cases diagnosed with type 2 diabetic peripheral neuropathy,in accordance with the random number table,were divided into the control group(37cases) and treatment group(39cases).All the patients received diabetic diet,exercise guidance and blood glucose control.The control group was treated with methycobal 500μg muscle injection once a day for 2 weeks.The treatment group was treated besides above treatment with intravenous drip alpha lipoic acid 600mg once a day was added for 2 weeks.Then,the changes of motor nerve conduction velocity,sensory nerve conduction velocity and quality of life(QoL) score(somatic symptoms,cognitive function, health happy feeling,social participation,emotional state,work performance,life satisfaction and total score)of the two groups after treatment were observed. Results After treatment,the motor nerve conduction velocity of the control group were as follows:median nerve(40.7±4.5)cm/s,common peroneal nerves(41.3±4.9)cm/s,The sensory nerve conduction velocity of the control group were as follows:median nerve(38.6±4.3)cm/s,common peroneal nerves (38.3±4.5)cm/s.After treatment,the motor nerve conduction velocity of the treatment group were as follows:Median nerve(45.4±5.7)cm/s,common peroneal nerves(44.9±6.4)cm/s,The sensory nerve conduction velocity of the treatment group were as follows:Median nerve(45.0±2.0)cm/s,common peroneal nerves(43.6 ±3.2)cm/s.Both the two groups' motor nerve conduction velocity and sensory nerve conduction velocity were significantly increased after treatment(P< 0.05).Compared with control group,the motor nerve conduction velocity and sensory nerve conduction velocity in the treatment group were significantly improved after treatment,which had statistically significance,(t= 2.63,2.51,2.85,2.79,all P< 0.05).After treatment,the somatic symptoms,cognitive function,health happy feeling,job performance,social participation,emotional state,life satisfaction and the total score of control group were(52.4±9.6)points,(27.0±7.8) points,(35.7±10.3) points,(19.6±7.3) points,(17.4±3.1) points,(16.5±3.9) points,(185.4±40.7)points,respectively.After treatment,the somatic symptoms,cognitive function,health happy feeling,job performance,social participation,emotional state,life satisfaction and total score of treatment group were(41.9±7.4) points,(24.1±8.6) points,(28.3±9.2) points,(14.5±5.5) points,(12.6±5.6) points,(11.9±4.7)points,(135.0±38.7)points,respectively.The quality of life score of the treatment group was obviously lower than the control group,which had statistically significance,(t= 5.14,2.54,2.96,2.87,2.69,3.05,6.25, all P<0.05). Conclusion Alpha lipoic acid can improve the nerve conduction function of patients with type 2 diabetes peripheral neuropathy,and improve the quality of life. Key words: Diabetic neuropathies; Quality of life; Alpha lipoic acid

Background &amp; objective: Diabetes mellitus is quite common and globally prevalent condition affecting patients’ quality of life. Patients who have type 2 diabetes mellitus (T2DM), are more likely to get diabetic peripheral neuropathy (DPN), which may affect feet, legs, hand, and arm. A BDNF gene rs6265 polymorphism in humans results in the substitution of valine with methionine at codon 66 (Val66Met). We aimed to find the possible link between human BDNF rs6265 gene polymorphism and T2DM with and without peripheral neuropathy and compare it with healthy subjects in Kirkuk City, Iraq. Methodology: One hundred subjects were chosen to participate in this research, aged from 35 to 75 y and divided into three groups: 35 DPN, 35 T2DM patients, and 30 healthy controls were selected randomly for BDNF gene rs6265 SNP screening by using conventional PCR with specific sets of primers. Products of PCR for patients and control groups were run on the gel electrophoresis to detect the SNP rs6265 fragment. A nerve-conducting study was used to examine DPN. Results: The observed results demonstrated the presence of two types of alleles identified as genotypic variants (GG and GA) among all participants in this investigation. By applying the Hardy-Weinberg Equilibrium principle (HWE) for both patient and control groups, the results proved that there was a statistically significant variance (P &lt; 0.05) in the genotypic frequencies between each of the groups that had been studied. The wild homozygous GG genotype in type 2 diabetic without neuropathy, with DPN, and healthy control group were 51.4%, 40% and 80% respectively. The heterozygous GA genotype were 48.6%, 60% and 20%, respectively in the three groups. Conclusion: The present study showed that the BDNF (Val66Met) rs6265 polymorphism is associated with type 2 diabetes mellitus and diabetic peripheral neuropathy in heterozygous allele G/A (Met/Met) and homozygous allele GG (Val/Val) genotype. Also, the current study found the absence of the mutant genotype AA, possibly due to the evidence that the distribution of the BDNF polymorphisms varies widely among different ethnic groups. Abbreviations: BDNF - Brain-derived neurotrophic factor; DPN - Diabetic peripheral neuropathy Keywords: Type2 diabetes mellitus; Diabetic peripheral neuropathy; Brain-Derived Neurotrophic Factor; BDNF rs6265 SNP; BDNF Val66Met polymorphism. Citation: Hamid R, Al-Wasiti E, Jabbar AM. Correlation between human BDNF rs6265 gene polymorphism and type-2 diabetes and diabetic peripheral neuropathy. Anaesth. pain intensive care 2024;28(4):752−756. DOI: 10.35975/apic.v28i4.2517 Received: March 08, 2024; Reviewed: April 20, 2024; Accepted: April 28, 2024

Hyperbaric Oxygen therapy is recommended as an adjuvant therapy for diabetic neuropathy. To investigate olfactory dysfunction and show the effectiveness of hyperbaric oxygen treatment in patients with type 2 diabetic neuropathy. Patients diagnosed with Type 2 DM and diabetic neuropathy were included in the group 1. Patients of Group 1 were administered with a hyperbaric oxygen therapy for 30 sessions and patients who returned for a check up following 30 sessions were incorporated into the Group 2. Healthy volunteers with no medical problems were included in the study as a control group (Group 3). Connecticut Chemosensory Clinical Research (CCCRC) test and the subjective visual analog scale (VAS; 0-100) were utilized to evaluate the olfactory function. There was a statistically significant difference both between the control group and the patient group as well as before and after the HBO therapy in terms of total CCCRC scoring averages and VAS Scoring averages. When compared to normal individuals, type 2 diabetic neuropathy can cause an olfactory dysfunction, and a statistically significant improvement in olfaction can be obtained with HBO therapy. This is the first study demonstrating that the HBO therapy can play a role in treating olfactory dysfunctions suffered by the patients with diabetic olfactory neuropathies.

Objective To evaluate the clinical significance of quantitative sensory testing (QST) in screening diabetic peripheral neuropathy of the early stage. Methods One hundred patients with type 2 diabetes mellitus were examined by nerve conduction velocity (NCV) and QST examination. With the NCV positive as the gold criterion for screening diabetic peripheral neuropathy of the early stage, the sensitivity and specificity of QST was further analyzed for diagnosis of the early stage diabetic peripheral neuropathy. Results Among the 100 patients with type 2 diabetes mellitus,there were 41 cases positive and 59 cases negative in NCV examination. On the other hand,there were 74 cases positive,and 26 cases negative in QST. The sensitivity and specificity of QST for the diagnosis of early stage diabetic peripheral neuropathy was 97.56% (40/41) and 42.37% (25/59). Conclusions In the screening of early stage diabetic peripheral neuropathy,QST shows higher detection sensitivity,but lower specificity than NCV examination. Therefore, QST may be an examination for the supplement of the routine electromyography. Key words: Diabetic neuropathies; Sensitivity and specificity; Electromyography; Quantitative sensory testing

Objective To study the effect of alprostadil combined with epalrestat and methylcobalamin in the treatment of type 2 diabetic peripheral neuropathy. Methods From January 2014 to June 2016, 120 patients with type 2 diabetic peripheral neuropathy in the First People′s Hospital of Baiyin were randomly divided into two groups according to the random number table method.64 patients of the observation group were given the treatment of alprostadil, epalrestat combined with methylcobalamin.56 patients of the control group were given the treatment of alprostadil and methylcobalamin.And the two groups were treated for 4 weeks.The blood glucose, clinical symptoms, adverse reaction, nerve conduction velocity index were compared between the two groups before and after treatment. Results The fasting blood glucose and 2-hour postprandial blood glucose of the two groups after treatment were significantly decreased(t=18.20, 17.61, 15.75, 23.69, all P 0.05). Conclusion Alprostadil combined with epalrestat and methylcobalamin in the treatment of type 2 diabetic peripheral neuropathy has good effect. Key words: Diabetic neuropathies; Alprostadil; Epalrestat; Methylcobalamin

The aim of our study was to investigate possible associations between three SNPs: rs4673 in the CYBA gene; rs1041740 in the SOD1 gene; and rs1001179 in the CAT gene, and type 1 diabetes (T1D) or diabetic peripheral neuropathy (DPN) in T1D patients. Allelic variants of the selected SNPs were determined by allelic discrimination assays in 114 T1D patients enrolled in the study group and in 90 healthy individuals from a control group. Associations between each of the three SNPs were tested in subgroups of T1D patients divided according to the presence of DPN. The TT genotype of rs4673 in the CYBA gene was associated with DPN in T1D patients (OR 4.997, 95% CI 1.403-19.083, p = 0.016). Weak significance was observed for a protective effect of the TT genotype of rs1041740 in the SOD1 gene relative to T1D development (OR 0.318, 95% CI 0.092-0.959, p = 0.056). There was no significant association between the CAT gene SNP rs1001179 and T1D or DPN. We showed a strong association of the CYBA polymorphism rs4673 with DPN in Slovak children and adolescents with T1D. Further studies are necessary to assess the relationship between rs1041740 and T1D or DPN.

Hyperbaric Oxygen therapy is recommended as an adjuvant therapy for diabetic neuropathy. To investigate olfactory dysfunction and show the effectiveness of hyperbaric oxygen treatment in patients with type 2 diabetic neuropathy. Patients diagnosed with Type 2 DM and diabetic neuropathy were included in the group 1. Patients of Group 1 were administered with a hyperbaric oxygen therapy for 30 sessions and patients who returned for a check up following 30 sessions were incorporated into the Group 2. Healthy volunteers with no medical problems were included in the study as a control group (Group 3). Connecticut Chemosensory Clinical Research (CCCRC) test and the subjective visual analog scale (VAS; 0-100) were utilized to evaluate the olfactory function. There was a statistically significant difference both between the control group and the patient group as well as before and after the HBO therapy in terms of total CCCRC scoring averages and VAS Scoring averages. When compared to normal individuals, type 2 diabetic neuropathy can cause an olfactory dysfunction, and a statistically significant improvement in olfaction can be obtained with HBO therapy. This is the first study demonstrating that the HBO therapy can play a role in treating olfactory dysfunctions suffered by the patients with diabetic olfactory neuropathies.

Diabetic peripheral neuropathy (DPN) is a major cause of disability, mortality and poor quality of life in patients with T1D, with prior reported prevalence rates of up to 35%. The contemporary prevalence of DPN in T1D patients was evaluated in T1D Exchange Registry centers throughout the United States. The Michigan Neuropathy Screening Instrument (MNSI), a validated 15-item self-administered questionnaire, was used to assess DPN in adults ≥18 years with ≥ 5 years of T1D duration. A score of ≥4 was used to define DPN. Diabetes-related characteristics and laboratory data were obtained through the most recent clinic update. Chi-square and t-tests were used to compare demographic and diabetes-related characteristics between those with and without DPN. Linear regression was used to determine the effect of DPN on HbA1c, adjusted for possible confounders. In preliminary analyses of 5,058 participants across 62 sites (mean age 39±18 years, T1D duration 22±14 years, 56% female, 88% non-hispanic white, mean HbA1c 8.1±1.6%), the prevalence of DPN was 10%. Those with DPN were older (52±17 vs. 37±18 years), more likely to be female (61% vs. 55%), had longer T1D duration (32±16 vs. 21±13 years), lower annual household income (37% vs. 59% earning ≥$75K), and lower education level (55% vs. 69% with college degree) than those without DPN (all p&amp;lt;0.001). They also had higher systolic blood pressure (126±17 vs. 123±14 mmHg), triglycerides (117±89 vs. 95±62 mg/dL), tobacco use (9% vs. 4%) and prevalence of established CVD (26% vs. 6%), despite higher use of CVD-modifying agents such as statins (64% vs. 31%) and ACE-inhibitors/ARBs (45% vs. 23%) (all p&amp;lt;0.001). Participants with DPN had higher HbA1c (8.4±1.7% vs. 8.1±1.6%), even after adjusting for multiple confounders (p &amp;lt;0.01). The prevalence of DPN in this national T1D cohort is lower than prior published reports, reflecting current clinical care practices, and highlighting other non-glycemic risk factors for DPN including CVD risk factors and socioeconomic status. Disclosure K.R. Mizokami-Stout: None. C.T. Boyle: None. V.N. Shah: None. G. Aleppo: Research Support; Self; AstraZeneca, Novo Nordisk Inc.. Consultant; Self; Dexcom, Inc.. Advisory Panel; Self; Novo Nordisk Inc. J.B. McGill: Research Support; Self; AstraZeneca. Consultant; Self; Boehringer Ingelheim GmbH. Speaker's Bureau; Self; Aegerion Pharmaceuticals. Consultant; Self; Bayer AG, Dexcom, Inc., Intarcia Therapeutics, Inc.. Speaker's Bureau; Self; Janssen Pharmaceuticals, Inc., MannKind Corporation. Research Support; Self; Novartis Pharmaceuticals Corporation. Consultant; Self; Novo Nordisk A/S. R. Pratley: Other Relationship; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eisai Inc., GlaxoSmithKline plc., Janssen Pharmaceuticals, Inc., Lexicon Pharmaceuticals, Inc., Ligand Pharmaceuticals, Inc., Eli Lilly and Company, Merck &amp; Co., Inc., Novo Nordisk Inc., Pfizer Inc., Sanofi-Aventis, Takeda Development Center Americas, Inc.. E. Toschi: None. L. Ang: None. R. Pop-Busui: Research Support; Self; AstraZeneca.

Objective To evaluate the relationship between 25-(OH) vitamin D [25-(OH) D] level and peripheral neuropathy in patients with type 2 diabetes mellitus.Methods Eighty patients with type 2 diabetes mellitus were enrolled in this cross-sectional study,including 37 subjects with and 43 without diabetic neuropathy.Anthropometric data was collected and serum levels of 25-(OH) D,HbA1c,blood lipid,and hepatic and renal functions were determined in all patients.Results Serum 25-(OH) D level was significantly lower in patients with diabetic neuropathy compared to those without neuropathy [(12.73 ± 4.68 vs 17.56 ± 5.28) ng/ml,P＜0.01].Logistic regressions demonstrated that vitamin D level was associated with diabetic neuropathy (OR=1.222,95％ CI 1.095-1.364).Conclusions Vitamin D insufficiency is associated with diabetic peripheral neuropathy.25-(OH) D level seems to be an independent risk factor of diabetic neuropathy in patients with type 2 diabetes mellitus. Key words: Diabetes mellitus, type 2 ; Diabetic peripheral neuropathy; Vitamin D

Background: Deficits in finger proprioception might impact the ability to perform tasks such as picking up pills, monitoring blood sugar and injecting insulin. However, no tests are available for finger proprioception with functional relevance for tasks using pinch between the index finger and thumb. This study investigates the impact of diabetic peripheral neuropathy (DPN) on pinch proprioception in people with type 2 diabetes (T2D). Methods: This study tested pinch proprioception in 8 healthy participants (3 males, 57±5.6 years), 11 participants with T2D without DPN (T2D-only) (5 males, 61±5.9 years), and 13 participants with T2D and DPN (T2D+DPN) (6 males, 59.9±6.4 years). We used a device previously tested for reliability. Following familiarization with a 15° target position of the index finger and thumb, subjects performed 3 trials where they attempted to reproduce the target position without visual feedback. The average of the absolute error matching the 15° target represented accuracy, and the standard deviation from the trials denoted precision. Results: Descriptive statistics presented as Means ± SD. Accuracy: healthy (0.67±0.64), T2D-only (0.94±1.2), and T2D+DPN (3.51±2.24). Precision: healthy (0.59±0.41), T2D-only (0.79±0.53), and T2D+DPN (2.81±2.4). Kruskal-Wallis test was significant for accuracy (p = .003) and precision (p = .001). Pinch proprioception was significantly different between the T2D+DPN group and the T2D-only group (accuracy and precision: p = .003) as well as between the T2D+DPN group and the healthy group (accuracy: p = .006; precision: p = .001). There were no significant differences between the T2D-only group and the healthy group: accuracy (p = .98) and precision (p = .5). Conclusion: Our results showed that pinch proprioception was disrupted in people with DPN, but not in people with T2D without DPN. Detection of pinch proprioceptive deficits will potentially improve the neurological screening and can be used in future studies for other neurological populations. Disclosure A. Yahya: None. P. Kluding: None. M. Pasnoor: None. M. Santos: None.

Objective To investigate the clinical effect and safety of alpha lipoic acid injection combined mecobalamin and prostaglandin E on type 2 diabetic patients complicated with diabetic peripheral neuropathy(DPN).Methods One hundred and sixty type 2 diabetic patients complicated with DPN in the General Hospital of Benxi Iron and Steel Group Corporation from Jan.2011 to Dec.2012 were randomly divided into the treatment group(n =80) and the control group (n =80).Three cases of the treatment group and 5 cases of the control group discharged early from the study because of their own reasons.There were 77 cases in the treatment group and 75 cases in the control group.On the basis of controlling blood glucose,patients in the two groups were given 500 μg mecobalamin combined with intramuscular injection once two days,as well as prostaglandinE 10 μg injection once a day.Patients in treatment group were added with 600 mg alpha lipoic acid for intravenous injection once a day for 10-14 days.Total symptom score (TSS),nerve conduction velocity,satisfaction and adverse reactions were evaluated before and after treatment.Results TSS score,tingling score,burning sensation score and hypoesthesia score,numb score in treatment group were (3.5 ± 2.5),(1.1 ± 0.4),(0.9 ± 0.7),(1.3 ± 0.4),(1.3 ± 0.9),significantly lower than those in control group (4.3 ± 2.1,t =2.11,P ＜0.05;1.5 ±0.5,t =1.86,P＜0.05;1.3 ±0.5,t =1.83,P ＜0.05;1.7 ±0.5,t =1.87,P ＜0.05; 1.9 ± 0.4,t =1.91,P ＜ 0.05).The median nerve conduction velocity,peroneal nerve motor conduction velocity,median nerve sensory conduction velocity,common peroneal nerve sensory conduction velocity of patients in treatment group were (53.6 ± 1.4) m/s,(49.6 ± 1.1) m/s,(47.3 ± 1.1) m/s,(48.2 ± 1.9) m/s,lower than those in control group((48.5 ±2.7) m/s,t =-4.94,P ＜0.05;(43.9 ±2.1) m/s,t =-5.36,P ＜0.05; (41.6 ± 1.8) m/s,t =-5.09,P ＜0.05;(43.2 ±2.5) m/s,t =-4.27,P ＜ 0.05,P ＜0.05).In the treatment group,97.4％ (75/77) physicians and 92.2％ (71/77) patients were satisfied with treatment effect,while in the control group,84.0％ (63/75) physicians and 78.7％ (59/75) patients were satisfied with treatment effect.During the study periods,there were 3 cases with facial flushing and 1 cases of dizziness in the treatment group,and 2 cases of facial flushing and 1 cases of dizziness in the control group.All adverse reactions were spontaneous remission without any special treatment.Conclusion Alpha lipoic acid intravenous drip is effective in term of treating type 2 diabetic peripheral neuropathy,and with high safety. Key words: Type 2 of diabetic mellitus; Diabetic peripheral neuropathy; Alpha lipoic acid; Mecobalamin; Prostaglandin E

BackgroundThe aim was to investigate the relationship between diabetic peripheral neuropathy (DPN) and abnormalities in ganglion cell complex (GCC); specifically, focal loss volume (FLV) and global loss volume (GLV).MethodsThe ganglion cell complex was evaluated using optical coherence tomography on 193 individuals (84 with type 1 diabetes, 67 with type 2 diabetes and 42 without diabetes). In those with diabetes, 88 had diabetes but no diabetic retinopathy (no DR group) and 63 had diabetes with diabetic retinopathy (DR group). Seventeen individuals in the no DR group and 27 in the DR group had diabetic peripheral neuropathy according to the neuropathy disability score (NDS). The probability of FLV and GLV being abnormal was determined. Forty four individuals had diabetic peripheral neuropathy (NDS of three or greater). Binary logistic regression analysis was performed, adjusting for the presence of diabetic retinopathy, age, sex, type of diabetes, duration of diabetes and HbA1c levels.ResultsTwenty‐five per cent of individuals with diabetic peripheral neuropathy had abnormal FLV compared to 11 per cent of those with diabetes but no diabetic peripheral neuropathy and five per cent in the control group (p = 0.011). Fourteen per cent of individuals with diabetic peripheral neuropathy, 10 per cent without diabetic peripheral neuropathy and two per cent in the control group had abnormal GLV (p = 0.185). For every unit increase in the neuropathy disability score, the odds of having an abnormal FLV increased by a factor of 1.25 (p = 0.007), after adjusting for potentially confounding factors. Abnormal GCC FLV is an independent predictor of diabetic neuropathy, (odds ratio = 2.94, 95 per cent CI [1.16, 7.40], p = 0.023).ConclusionDiabetic peripheral neuropathy is associated with abnormal GCC FLV at the macula, which is independent of diabetic retinopathy, age, sex, type of diabetes, duration of diabetes and HbA1c levels. An abnormality in GCC FLV is an independent predictor of diabetic peripheral neuropathy.

In this issue of the journal, Gouveri et al report on olfactory dysfunction among patients with type 2 diabetes mellitus (T2DM) and raise the question whether it might be considered as an additional manifestation of microvascular disease. 1 Diagnostic methods to assess olfactory dysfunction are well established and validated: odor-dispensing devices, so-called ‘‘Sniffin’ Sticks,’’ are used and a total threshold–discrimination–identification (TDI) score is calculated. Age was negatively associated with the TDI score. After adjusting for age, gender, various risk factors, and cardiovascular disease, only T2DM and hypertension were associated with the TDI score. Olfactory dysfunction was associated with retinopathy and diabetic peripheral neuropathy. The latter finding should be considered particularly important. We agree with the authors that olfactory dysfunction may develop due to olfactory nerve impairment. This way, it should be regarded as a novel manifestation of central neuropathy. The term ‘‘diabetic neuropathy’’ refers to disorders of the peripheral nervous system due to neuropathy. However, we now know that dysfunction of the central nervous system is also present among diabetic patients. Cognitive impairment, 2 as well as depression, 3 is well recognized in diabetes. Cranial neuropathies are less frequent, most likely often overlooked, but well established manifestations of diabetic neuropathy. The impairment of cranial nerves is defined as a form of mononeuropathy. Cranial neuropathies are more frequent in older patients with long diabetes duration. Most of these patients have several comorbidities and their glycemic control is rather poor. 4 Isolated palsy of the third, fourth, or sixth cranial nerves is a characteristic manifestation of diabetic neuropathy. The presence of multiple, painless cranial nerve palsies in diabetic patients, even without other associated neurological deficits, may represent midbrain ischemia. 5 The incidence of cranial nerve involvement is 1% in diabetic patients. 6 Isolated third nerve palsies account for the majority of patients 4 and 11% of inpatients with third nerve palsy had diabetes. 7 The onset of cranial neuropathy is usually abrupt, with progression

Objective To investigate the relationship between retinal nerve fibre layer (RNFL) thickness and peripheral neuropathy in patients with type 2 diabetes. Methods Ninety-eight cases diagnosed with type 2 diabetes in the Department of Endocrinology in Beijing Hospital from March 2014 to June 2015 were enrolled in this study. Global and sectoral RNFL thicknesses were measured at 3.45 mm diameter around the optic nerve head using optical coherence tomography(OCT), and conduction velocity of peripheral nerve was measured in all cases. According to the diagnosis of diabetic neuropathies, participants were divided into 3 groups: non-diabetic peripheral neuropathy group(NDPN, n=36), subclinical diabetic peripheral neuropathy group(SDPN, n=37) and define diabetic peripheral neuropathy group(DDPN, n=25). RNFL thickness in different group was compared by analysis of variance and least-significant difference pairwise comparison. Results All sectoral RNFL thickness was thinning from NDPN group, SDPN group to DDPN group, specially inferior quadrant RNFL thickness, and there was significant difference among the three groups((132±19), (124±18) vs (116±17)μm, F=5.848, P=0.004). And significant difference was found in inferior quadrant RNFL thickness between NDPN and SDPN group(mean difference=8.67 μm, t=1.975, P=0.048), NDPN and DDPN group (mean differenc=16.59 μm, t=3.412, P=0.001). No significant difference was found in inferior quadrant RNFL thickness between SDPN and DDPN group(mean difference=7.93 μm, t=1.661, P=0.104). Covariance analysis showed that age and diabetes duration had no significant influence on RNFL thickness. Conclusions RNFL thickness maybe associated with diabetic peripheral neuropathy in patients with type 2 diabetes, especially in serious cases. Key words: Diabetes mellitus, type 2; Retinal nerve fibre layer; Diabetic peripheral neuropathy