The electrophysiological findings of subclinical neuropathy in patients with recently diagnosed type 1 diabetes mellitus

To assess the prevalence of subclinical neuropathy within the first year of type 1 diabetes mellitus, 30 patients and 14 healthy subjects have been studied prospectively. The patients whose diabetes duration was longer than 1 year have been excluded from the study. Control group consisted of healthy volunteers. Subjective neuropathy symptoms, neurological examination, and electrophysiological findings were evaluated. All patients were clinically asymptomatic. At least two abnormal independent neurophysiological nerve parameters, which were required as the criterion of the peripheral nervous system subclinical involvement, were found as in 96.6% of diabetic patients in the first years. The percentages of abnormal electrophysiological parameters in different motor and sensory nerves were 86.7% in sural nerve, 83.3% in peroneal motor nerve, 73.3% in posterior tibial motor nerve, 66.7% in median motor nerve, 63.3% in ulnar motor nerve, 60% in median sensory nerve, and 46.7% in ulnar sensory nerve. While distal motor latency, F conduction time, and minimum F latency were the most frequent abnormal parameters in the upper extremity electrophysiological study; conduction velocity, minimum and mean F latencies, F conduction time were the most frequent abnormal parameters in the lower extremity. In all sensory nerve conduction studies, the most frequent abnormal parameter was the onset latency. In the autonomic sympathetic nerve electrophysiological study, plantar SSR latency was found significantly longer than the control group. In the lower extremity generally somatic motor fibres, sensory large fibres and sympathetic autonomic nerve fibres were found to be more affected. There is a correlation between HbA1c levels and nerve conduction velocity in posterior tibial and peroneal nerves. However, upper extremity nerve conduction dysfunction was not correlated with HbA1c value. Neither the duration of disease nor the age of the subject correlated with the nerve dysfunction.     

Near normoglycaemia improved nerve conduction and vibration sensation in diabetic neuropathy

Summary Twelve C-peptide deficient Type 1 (insulin-dependent) diabetic patients with abnormal peripheral nerve function were randomly assigned to continuation of conventional insulin therapy (CIT) or to continuous subcutaneous insulin infusion (CSII). There were no statistically significant differences at entry to the study between the two treatment groups in nerve function assessed by neurologic disability score, computer assisted sensation examination and measurements of amplitudes, distal latencies, F-wave latencies and somatosensory evoked potential latencies over the spine and conduction velocities of motor and sensory fibers of ulnar, median, peroneal, tibial, plantar and sural nerves. In addition, mean plasma glucose from 24 h profiles (12.5 vs 10.6 mmol/l, respectively) and HbA₁ (11.0 vs 11.6%, respectively) did not differ significantly between the two treatment groups at entry. Despite improved glycaemia from CSII in 5 patients (one dropped out of the study after 2 months) contrasted to CIT in 6 patients (5.3 vs 9.9 mmol/l, respectively, p=0.002) and HbA1 (8.5 vs 10.7%, respectively, p=0.002), there were no significant differences in measurements of peripheral nerve function after 4 months. After 8 months of improved glycaemia (4.4 vs 10.2 mmol/l, p=0.004) and improved HbA₁, (8.3 vs 10.5%, p=0.002), nerve conduction (p=0.03) and vibratory sensation threshold (p=0.002) were significantly better in patients treated with CSII than those who received CIT. The improvements in nerve function, although small, provide further evidence that some clinical endpoints of neuropathy are favorably influenced by improved control of glycaemia.     

Effect of glycemic control on electrophysiologic changes of diabetic neuropathy in type 2 diabetic patients

Diabetic neuropathy is a common complication of diabetes mellitus. Effective blood glucose control retards changes in nerve conduction velocity in type 1 diabetes. This study examined the relationship between glycemic control and electrophysiologic changes in diabetic neuropathy in 57 type 2 diabetic patients. Nerve conduction in the peroneal motor nerve, tibial motor nerve, and sural nerve were measured at study entry and at follow-up 24+/-3.12 months later. Changes in individual nerves are expressed as a percentage change (PC) and overall electrophysiologic changes are expressed as the sum of individual PCs. The PCs for peroneal motor nerve velocity, tibial motor nerve velocity, and sural nerve velocity were all lower in patients with a mean HbA1c of 8.5% or less compared with those in patients with a mean HbA1c of more than 8.5%, and SPCV (sum of PC in velocity) was significantly inversely correlated with mean HbA1c. However, there was no significant difference in SPCV in subjects with or without hypertension, hypertriglyceridemia, or low high-density lipoprotein cholesterol concentration. In conclusion, hyperglycemia is the most important etiology for electrophysiologic progression in type 2 diabetic patients. Furthermore, a mean HbA1c of more than 8.5% will result in significant deterioration in electrophysiology.     

Prevalence of peripheral neuropathy and associated risk factors in children with type 1 diabetes

AimTo detect the prevalence of diabetic polyneuropathy (DPN) in children with type 1 diabetes (T1D) and to identify associated the risk factors.MethodsThis cross-sectional study evaluated children aged between 2 and 16y with T1D for ≥2 y. Detailed neurological examination, neuropathy symptom score, and nerve conduction studies were done in all children to assess nerve dysfunction. Disease-related factors were evaluated for the prediction of neuropathy.ResultsSixty-six children (67% boys) were enrolled. The mean age at the time of diagnosis of T1D was 7.1 ± 2.6 years. The mean duration of diabetes was 4 ± 1.8 years. None of the patients had neuropathy on clinical examination or on the neuropathy symptom score. The prevalence of subclinical DPN was 18.2% (n = 12/66). The type of neuropathy was pure motor (n = 11, 91.6%) and mixed sensorimotor (n = 1, 8.3%). The common peroneal nerve was most commonly affected (n = 6, 50%), followed by the tibial (n = 4, 33.3%) nerve. The most common patterns of nerve involvement were mixed axonal and demyelination (n = 7, 58.3%), followed by axonal (n = 3, 25%) and demyelinating type (n = 2, 16.6%). Children with subclinical DPN had a significant reduction in velocity of tibial, common peroneal, median motor, and ulnar motor nerves; delayed latency in common peroneal, median motor, ulnar motor, and median sensory nerves compared to those without DPN (p value <0.05). A higher body mass index predicted the development of subclinical DPN (p value <0.05).ConclusionNearly one-fifth of children with T1D have subclinical neuropathy as early as two years of the disease. A higher body mass index is significantly associated with DPN. Electrophysiological studies should be performed regularly to screen for nerve dysfunction and its progression.     

Possible contribution of adipocytokines on diabetic neuropathy

Neuropathy is one of the typical features of chronic complications of diabetes mellitus. Recent analyses indicate that subjects with impaired glucose tolerance (IGT) already have disturbance of peripheral nerve function. To test the role of adipocytokines, that tend to be abnormal in IGT subjects, on diabetic neuropathy, we analyzed the relationship between plasma adipocytokine levels (TNFalpha, adiponectin, and leptin) and nerve conduction velocity in 105 type 2 diabetic subjects (M/F = 66/39, age = 60.8 +/- 11.8 years, BMI = 24.7 +/- 5.0kg/m2). Adipocytokines were measured by ELISA, and motor conduction velocity (MCV) and sensory conduction velocity (SCV) in median, ulnar, and tibial nerve were measured by electrical stimulation. Motor conduction velocity and SCV were corrected by age to be 1.0 as the normal value, and the average of three nerves were used to be the representative value. Relationship between corrected MCV or corrected SCV as a dependent variable and the duration of diabetes, HbA1C, BMI, TNFalpha, adiponectin, and leptin concentrations as independent variables were analyzed by multiple regression. Duration of diabetes and HbA1C were highly related with both corrected MCV (P < 0.02 and P < 0.001) and SCV (P < 0.02 and P < 0.05) by this analysis. Only corrected SCV was related significantly with TNFalpha (P < 0.05), and close to significantly with leptin (P = 0.059) concentrations. These results indicate that increased plasma glucose levels and duration of diabetes are the major factors that modulate diabetic neuropathy. However, nerve function may be affected by plasma cytokine levels like TNFalpha, and this effect was more significant on sensory nerves than motor nerves. The present results suggest that adipocytokines may play a role not only on angiopathy but also on neuropathy in diabetics.     

Subclinical nerve dysfunction in children and adolescents with IDDM

Summary The purpose of this study was to investigate whether young insulin-dependent diabetic patients still develop peripheral nerve dysfunction when using modern multiple insulin injection therapy and to elucidate if this correlated with various disease parameters. Seventy-five patients, 7 to 20 years old with a duration of diabetes of more than 3 years, and 128 age-matched healthy control subjects underwent bilateral studies of median, peroneal, and sural nerves. Presence of diabetes lowered motor conduction velocity (p<0.0001), sensory conduction velocity (p<0.0001) and sensory nerve action potential (p<0.05) in all examined nerves. The mean change in conduction velocity induced by diabetes was –4.8 m/s in the peroneal nerve, –3.3 m/s in the median motor nerve, –2.6 m/s in the sural nerve and –2.4 m/s in the median sensory nerve. Fifty-seven percent of the patients had abnormal conduction (values outside 95% predictive interval) which was seen most often in the motor nerves, especially in the peroneal nerve (41%) followed by the median nerve (24%). In multiple regression analysis, long-term poor metabolic control and increased body length correlated with nerve dysfunction identified in most examined parameters. Three patients had signs or symptoms suggestive of neuropathy. It is concluded that despite modern multiple insulin injection therapy, with reasonably good metabolic control, nerve dysfunction is still common in children and adolescents with insulin-dependent diabetes mellitus. Risk factors are increased height and long-term poor metabolic control.Abbreviations IDDM Insulin-dependent diabetes mellitus - MIT multiple insulin injection therapy - MCV motor nerve conduction velocity - CMAP compound muscle action potential - DML distal motor latency - SCV sensory nerve conduction velocity - SNAP sensory nerve action potential     

Early electroneurographic diagnosis of carpal tunnel syndrome (author's transl)]

A comparison of distal motor latencies after stimulation of the median and ulnar nerves proximal to the ligamentum carpi transversum and recording from the thenar muscles shows: a) in normal subjects (99 measurements) a 0,7 msec longer latency after stimulation of the ulnar nerve, b) in generalized polyneuropathies in 46% (n = 48) a reversal of the two motor latencies, i.e., a longer median than ulnar nerve latency. c) in manifest carpal tunnel syndromes with pathologically prolonged motor latencies this reversal in all cases; d) in carpal tunnel syndromes with only pathologically prolonged sensory latencies in 11 out of 13 patients a reversal of motor latencies; e) in patients with carpal tunnel syndromes a reversal of motor latencies in 65% (n = 46) on the clinically symptom-free side. It is concluded that a reversal of distal motor latencies may be the earliest sign of a carpal tunnel syndrome, if a generalized polyneuropathy is excluded and typical symptoms are reported.     

The value of electromyographic studies in leprosy

In Dakar, during a definite period of time, all the new leprosy cases have been subjected to an electromyographic examination before treatment: a total of 37 patients and 518 examined nerves including all clinical forms: NCV: 33% of the examined nerves are found to be affected. The sensory nerves are frequently and early involved. In frequency order: sural (54%), posterior tibial (50%), sensory ulnar (35%), sensory median (29%), motor ulnar (28%), lateral popliteal (17%) and motor median (12%). The study of the SCV seems relatively more reliable than the sensory testing in the case of the ulnar and the median (75 comparisons): concordance in 69% of the cases; SCV only abnormal in 19%; sensory testing only abnormal in 12%. The EMG detection is superior to the motor testing and to the motor nerve conduction for the lateral popliteal (32 comparisons): 41% of concordant examination; 59% of differences among which 44% of anomalies revealed only by detection.     

Influence of continuous subcutaneous insulin infusion (CSII) treatment on diabetic somatic and autonomic neuropathy

Near-normal plasma daily glucose profile was induced by Continuous Subcutaneous Insulin Infusion (CSII) treatment in order to evaluate its influence on diabetic somatic and autonomic neuropathy. Twelve insulin-dependent diabetic subjects with somatic neuropathy were studied before and after a short term CSII treatment of 10 days. Four out of these subjects, all affected by autonomic neuropathy, were followed for 1 yr with controls every four months. Metabolic equilibrium was monitored by mean daily plasma glucose (MPDG) profile and by Glycosylated Hemoglobin (GHb) evaluation. Somatic neuropathy was studied assessing conduction velocity at peroneal motor (PMCV) nerve, ulnar motor (UMCV), ulnar sensory (USCV) and sural sensory (SSCV) nerves. Autonomic neuropathy was assessed by means of a battery of five cardiovascular autonomic tests: Valsalva Manoeuvre (VR), Deep Breathing (DB), Lying-to-Standing (LS), Sustained HandGrip (SHG) and Postural Hypotension (PH). Short-term CSII treatment induced a near normalization of metabolic parameters, a significant improvement in VR (p less than 0.05) and DB (p less than 0.01) values, but no changes in NCV. The prolongation of CSII treatment in 4 subjects induced a significant (p less than 0.05) improvement in VR, DB and LS values and in PMCV and UMCV after 4 months. This improvement did not increase with the longer CSII treatment (1 yr).(ABSTRACT TRUNCATED AT 250 WORDS)     

高尿酸血症对2型糖尿病患者周围神经病变的影响及其与胰岛素抵抗的关系

目的 探讨高尿酸血症对2型糖尿病患者周围神经病变的影响及其与胰岛素抵抗的关系.方法 选取2009年7月至2010年1月于山西省人民医院内分泌科住院治疗的2型糖尿病合并周围神经病变患者90例为研究对象,其中男42例,女48例,平均年龄(55±4)岁.将90例患者根据血尿酸(UA)水平,分为高尿酸组(HUA)42例、正常尿...     

糖尿病周围神经病变的神经传导检查特点

目的 分析神经传导检查在糖尿病周围神经病变（DPN）中的特点,提高此方法诊断DPN的敏感性. 方法 对符合标准的213例患者的2283条神经行传统的神经传导、F波、H反射检查,并分析各条神经总的神经电生理检查情况. 结果 2283条神经进行常规神经传导检查结果显示,感觉神经传导速度（SCV）中,正中神经的异常率最高;运动神经传导速度（MCV）中,胫神经、正中神经异常率高;最长的胫神经运动神经神经传导异常率为47.45％,容易合并卡压的正中神经感觉神经传导异常率为46.83％,而腓肠神经感觉神经传导异常率最低（22.60％）.对有临床明确症状的21条神经进行神经传导检查,异常率可达76.19％.对感觉神经传导异常的尺神经进行运动神经传导检查,尺神经异常率为57.14％.常规神经传导检查,正中神经感觉神经传导异常率（46.83％）高于正中神经运动神经传导异常率（41.13％）.正中神经感觉神经传导异常者运动神经传导异常率为76.56％,正中神经运动神经传导异常者感觉神经传导异常率为89.63％.尺神经F波、胫神经H反射的异常率分别为25.83％、52.24％.结论 DPN具有长度依赖性、与临床表现一致、感觉重于运动、全长弥漫受累等特点,根据这些特点选择神经进行神经传导检查,可提高神经传导检查诊断DPN的敏感性.     

Nerve conduction velocity study of the upper limb in Raynaud's phenomenon

A prospective study of upper limb nerve conduction velocity was performed in 39 subjects (9 males, 30 females, mean age 46.8 years) with idiopathic Raynaud's phenomenon (RP) and 18 patients (3 males, 15 females, mean age 49.9 years) with RP secondary to systemic sclerosis (SS). Five subjects with idiopathic RP (13%) showed slowing of sensory conduction velocity (SCV) of the distal median nerve, associated with delayed distal motor latency (DML) of the same nerve in three patients, without clinical signs or symptoms of carpal tunnel syndrome (CTS). Three patients with secondary RP (17%) had reduction of SCV of the distal median nerve, associated with increased DML of the same nerve in one and with clinically silent slowing of SCV of the ulnar nerve in two (11%). Mean distal SCVs of the median nerve were significantly lower and mean DMLs were significantly higher in both groups with respect to a control group. Mean distal conduction of the ulnar nerve was significantly slower only in the group with secondary RP. No slowing was observed in the proximal part of any nerve. It seems likely that patients with idiopathic RP have slowing of conduction in the distal part of the median nerve, along the carpal tunnel. Since slowing does not occur in all parts of the nerves of the hand, it cannot be related to acral vasomotor disturbances, but to local or systemic factors. In contrast, patients with secondary RP had slowing of median and ulnar nerve conduction velocity, presumably related to subclinical distal peripheral neuropathy. A nerve conduction study of the hand could be useful in cases of suspected secondary origin of RP. In idiopathic RP, slowing of conduction may only affect the median nerve, whereas in secondary RP it may affect other nerves of the hand. Received: 13 October 1999 / Accepted: 6 March 2000     

The significance of carpal tunnel syndrome in transthyretin Val30Met familial amyloid polyneuropathy

Carpal tunnel syndrome (CTS) is frequently reported in association with amyloidosis. We determined the significance of CTS in transthyretin Val30Met-associated familial amyloid polyneuropathy (FAP ATTR Val30Met) by comparing the electrophysiological indices of the median and ulnar nerves in 58 patients. As a whole, sensory nerve conduction velocity (SCV) was slowed and distal motor latency (DML) was prolonged to a similar extent in the median and ulnar nerves in these patients. The extent of abnormalities in the median nerve was almost similar to that in the ulnar nerve in both early-onset cases from endemic foci and late-onset cases from non-endemic areas. In age-matched idiopathic patients with CTS (20 patients, 27 hands), the slowing of SCV and the prolongation of DML in the median nerve were significant, while the slowing of motor conduction velocity was much less compared to FAP ATTR Val30Met patients. Although concomitant lesions in the ulnar nerve entrapment site at the wrist cannot be excluded, these findings indicate that CTS is not the sole distinctive feature in the majority of FAP ATTR Val30Met patients. The electrophysiological abnormality at the distal portion of the median nerve may be a consequence of polyneuropathy rather than an entrapment injury.     

High incidence of subclinical peripheral neuropathy in myelitis with hyperIgEaemia and mite antigen-specific IgE (atopic myelitis): an electrophysiological study

OBJECTIVE: To study subclinical involvement of the peripheral nerves in myelitis with hyperIgEaemia and mite antigen-specific IgE (atopic myelitis: AM). MATERIAL AND METHODS: We carried out a nerve conduction study of the median, ulnar, tibial, and sural nerves in 21 patients with AM and in 28 patients with clinically definite or laboratory-supported definite multiple sclerosis (MS). RESULTS: The patients with AM showed a significantly higher frequency of abnormal records than the MS patients in the sensory nerve conduction study (52.4% vs. 14.3%, p = 0.0106). The frequency of abnormal records in the motor nerve conduction study in AM patients was twice as high as in MS patients (38.1% vs. 17.9%), but the difference was not statistically significant. Abnormality in the F-wave-evoked frequency in the median nerve was also significantly more common in AM patients than in MS patients (57.9% vs. 10.7%, p = 0.0016). CONCLUSIONS: These findings suggest that subclinical peripheral neuropathy is frequent in patients with AM.     

Presence of carpal tunnel syndrome in diabetics: Effect of age,sex, diabetes duration and polyneuropathy

Summary Common thought is that diabetic neuropathy is a predisposing factor to entrapment syndromes. Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy; females and old people are most frequently affected (Comi et al., 1978). Prevalence of CTS in diabetics and associated risk factors were studied in 401 patients (208 males and 193 females) with insulin-dependent and non-insulin-dependent diabetes using electrophysiological techniques. Median nerve sensory and motor conduction velocity, ulnar and peroneal nerve motor conduction velocity and sural nerve sensory conduction velocity were investigated in all patients. Diagnostic criteria for CTS were the presence of delayed median nerve sensory conduction velocity in the palm-wrist tract and of increased distal motor latency. Polyneuropathy was defined by slowing-down of conduction velocity in two or more nerves. Forty-five patients (11.2%), 36 females and 9 males, showed CTS. One-hundred-sixty-eight patients (41.8%), 74 females and 94 males, were suffering from peripheral neuropathy. The strongest risk factors for CTS, in order of importance, were: female sex, older age and presence of neuropathy. Polyneuropathy but not CTS was related to duration of diabetes.     

Diagnostic utility of ultrasonography versus nerve conduction studies in mild carpal tunnel syndrome

OBJECTIVE: To prospectively compare high-resolution ultrasonography (US) and nerve conduction velocity (NCV) in clinically diagnosed mild carpal tunnel syndrome (CTS). METHODS: Eighty-five patients (70 women and 15 men, mean age 46.8 years) reported symptoms compatible with classic/probable CTS. The protocol included NCV of the median and ulnar nerves (distal motor latency [DML], sensory conduction velocity [SCV] from the third [M3 SCV] and fourth fingers [M4 SCV] to the wrist for the median nerve); electrophysiologic severity scale; self-administered Levine/Boston questionnaire (BQ); and cross-sectional area (CSA) measurement of the nerve at the tunnel inlet (CSA-I), at the middle (CSA-M), and at the outlet (CSA-O). Relationship between age, body mass index, duration of symptoms, CSAs, NCV, electrophysiologic severity scale, and BQ scores was calculated. Concordance between CSAs and NCV, sensitivity of NCV and US was also evaluated. RESULTS: The mean values of CSA-I, CSA-M, and CSA-O were 10.3, 9.8, and 8.7 mm2, respectively. Relationships were found between CSA-I and M3 SCV (r = -0.45), M4 SCV (r = -0.56), and median nerve DML (r = 0.29). Anomalous CSA-I, CSA-M, and CSA-O were found in 48, 25, and 26 patients, respectively; 55 (64.7%) had > or =1 abnormal CSA. NCV abnormalities were found in 67%. The sensitivity increased to 76.5% if US and NCV were considered together. The highest concordance to detect absence/presence of abnormalities was between CSA-I and NCV (77.6%; kappa = 0.52). CONCLUSION: In mild cases of CTS, US did not detect more anomalies than NCV and vice versa, and no anomalies were detected with either diagnostic instrument in 23.5% of mild cases.     

Femoral versus peroneal neuropathy in diabetic children and adolescents--relationships to clinical status, metabolic control and retinopathy

In order to estimate the prevalence of diabetic neuropathy in proximal and distal peripheral nerves, femoral and peroneal motor conduction was evaluated in 61 diabetic children, adolescents and young adults whose type 1 diabetes had become clinically apparent before the age of 14 years. Femoral motor nerve conduction velocity (FMNCV) in diabetic patients (63.8 +/- 10.4 m/sec) was not significantly different from FMNCV in control subjects (65.6 +/- 7.1 m/sec). By contrast, peroneal motor nerve conduction velocity (PMNCV) in diabetic patients (50.2 +/- 6.9 m/sec) was significantly lower than in controls (54.1 +/- 3.5 m/sec). Distal motor weakness, sensory deficit and absent Achilles reflexes were strongly correlated to impaired motor conduction in peroneal and also in femoral nerve. Peroneal nerve abnormality was negatively correlated with HbA1 levels, while femoral nerve abnormality was positively correlated with the presence of retinopathy. This discrepancy is not fully understood. Age and duration of diabetes were unrelated to femoral or peroneal motor nerve conduction velocity. Our data emphasize the frequent occurrence of subclinical proximal neuropathy in diabetic children and adolescents.     

糖尿病周围神经病700例临床与神经电生理分析

目的探讨糖尿病周围神经病的临床和电生理特点,明确电生理检查的诊断价值。方法对700患者进行感觉和运动神经传导测定,240例患者进行针极肌电图测定。结果507例(724%)患者电生理检查异常,其中307例(606%)为多发性周围神经病,74例(146%)为腕管综合征;感觉神经传导异常程度重于运动神经,波幅的下降程度较传导速度减慢明显,下肢重于上肢(P<005)。仅有46%的患者针极肌电图异常而神经传导正常。结论糖尿病周围神经病的临床和电生理表现均以感觉神经受损为主;电生理检查有助于发现临床病变,但并非所有患者均能发现电生理异常;建议不将针极肌电图进行糖尿病周围神经病的筛查作为常规使用。     

The natural history of somatosensory and autonomic nerve dysfunction in relation to glycaemic control during the first 5 years after diagnosis of Type 1 (insulin-dependent) diabetes mellitus

Summary The natural evolution of neural dysfunction was studied prospectively over 5 years following diagnosis of Type 1 (insulin-dependent) diabetes in 32 patients aged 12–36 years. Motor and sensory nerve conduction velocities, heart rate variation at rest and during deep breathing, and pupillary function were measured at diagnosis and after 3,12, 24,48, and 60 months. Thermal and vibration sensation thresholds were determined after 24, 48, and 60 months of diabetes. Mean HbA₁ levels of months 3–60 within the normal range of <8.3% (7.3±0.2%) were observed in 13 patients (Group 1), while a mean HbA₁ of months 3–608.3% (10.0±0.3%) was found in 19 patients (Group 2). Mean nerve conduction was significantly diminished in Group 2 as compared with Group 1 in at least 4 out of 6 nerves tested during months 12–60 (p<0.05). Both tests of heart rate variation were significantly impaired in Group 2 as compared with Group 1 after 24 and 60 months (p<0.05), but no differences in pupillary function were observed between the groups. Thermal discrimination but not vibration perception thresholds on the foot were significantly higher in Group 2 than in Group 1 at 40 and 60 months (p<0.05). Abnormalities in nerve conduction, thermal discrimination, and heart rate variation, but not vibration perception threshold and the pupillary function tests were significantly more frequent in Group 2 than in Group 1 at 60 months (p<0.05). After 60 months, none of the patients of Group 1, but 6 and 4 patients of Group 2 developed subclinical or symptomatic neuropathy, respectively (p<0.05). These findings suggest that the evolution of subclinical and symptomatic neuropathy during the first 5 years after diagnosis of Type 1 diabetes may be predicted by poor glycaemic control and prevented by near-normoglycaemia.     

Sustained improvement in diabetic control on long-term self-monitoring of blood glucose

The benefits of self-monitoring of blood glucose (SMBG) were assessed in 38 Chinese adults on conventional insulin regimens who had been performing SMBG for a mean duration of 26 months (range 15-40). For analysis patients were divided into 2 groups. Group A consisted of 27 insulin-requiring patients who were referred for SMBG because of poor control or young age (less than or equal to 35 years). Group B consisted of 11 IDDM patients who were on SMBG from diagnosis. Mean age and duration of SMBG were similar in the 2 groups though group A had longer duration of disease. In group A, mean haemoglobin A1 (HbA1) decreased from 12.4 +/- 0.5% before SMBG to 10.9 +/- 0.5% at 6 months (P less than 0.005), 10.7 +/- 0.5% at 12 months (P less than 0.005) and 10.3 +/- 0.4% after long-term SMBG. This was accompanied by a significant reduction in insulin requirement from 0.82 +/- 0.07 U/kg/day to 0.72 +/- 0.07 U/kg/day (P less than 0.05). In group B, insulin requirement progressively decreased in the first 6 months. At 12 months, mean HbA1 was 9.0 +/- 0.5% and insulin requirement was 0.58 +/- 0.08 U/kg/day. No significant change in HbA1 or insulin requirement was observed beyond the first year. After long-term SMBG, 82% of patients in group B had good control (HbA1 less than or equal to 10%) compared to 45% only in group A (P less than 0.05). Long-term SMBG is associated with sustained improvement in diabetic control and is particularly beneficial if introduced to diabetic patients right from diagnosis.