M. S. W. Lau

The effect of transcutaneous electrical nerve stimulation (TENS) on autonomic cardiovascular reflexes

Transcutaneous electrical nerve stimulation (TENS) has been shown to have an anti-ischaemic effect in patients with angina and peripheral vascular disease that appears to be additional to any analgesic action. The mechanism for this antiischaemic effect is not known but it is possible that TENS interferes with the autonomic responses to ischaemia. To determine if TENS has any direct action on autonomic reflexes we have assessed the effect of high frequency TENS on a variety of standard tests of autonomic cardiovascular reflexes in 10 normal subjects. Tests were done on four consecutive days at the same time and TENS therapy or placebo was randomly allocated on 2 days each. Results of the tests were assessed by one person ‘blinded’ to the randomization order. These showed that TENS was associated with a significant reduction in the rise of the diastolic blood pressure (21.8 ± 2.3 v. 17.6 ± 17 mmHg; p < 0.05) during isometric exercise, using sustained Handgrip. There was no significant effect discernible on the changes of heart rate and blood pressure during the Valsalva manoeuvre, cold face stimulus or headup tilt. Transcutaneous electrical nerve stimulation appears, therefore, to have a mild inhibitory action on those reflexes mediated predominantly by the sympathetic nervous system and this is more apparent when the stimulation may be greater, as during isometric exercise.

Antibodies to glutamic acid decarboxylase in young Chinese diabetic patients

Antibodies to glutamic acid decarboxylase (GAD) are a useful autoimmune marker for type 1 diabetes mellitus in Caucasians. We examined antibodies to GAD and their relationships with clinical features and pancreatic β cell function in 140 young Chinese diabetic patients. Over an 18-month period beginning in 1995, 140 young Chinese diabetic subjects with age of onset of disease ⩽ 35 years and age < 40 years were recruited consecutively, irrespective of their modes of presentation. Clinical features, antibodies to GAD and pancreatic β cell function (using a glucagon stimulation test) were examined. Increased levels of antibodies to GAD (>18 units) were detected in 12·1% (n> = 17) of these subjects. Forty-three (31%) patients had a classical type 1 presentation and 65 (46%) patients were insulin-deficient based on post-glucagon plasma C-peptide levels. Patients who were insulin-deficient and had a type 1 presentation had the highest prevalence of antibodies to GAD (29·0%) compared with patients who had a type 2 presentation and were non-insulin deficient (6·4%, P = 0·003). Patients who had antibodies to GAD had lower body mass index and waist—hip ratio, earlier onset of disease, lower blood pressure, plasma triglyceride and C-peptide, and higher concentrations of plasma high-density lipoprotein cholesterol and glycated haemoglobin, and were more likely to require drug treatment, compared with those without antibodies to GAD. In conclusion, there was a low prevalence of antibodies to GAD in Chinese young diabetic patients although such antibodies remained a relatively specific marker for insulin deficiency and acute presentation. Causes other than autoimmunity should be sought to explain the high prevalence of insulin deficiency in these young Chinese patients.

The short insulin tolerance test : Feasibility study using venous sampling

The short insulin tolerance test (ITT) is both a simple and valid method of quantifying insulin sensitivity although arterialization of samples and the risk of hypoglycaemia remain as potential difficulties. We examined the safety and reproducibility of using venous sampling with insulin doses of 0.1U kg−1 and 0.05 U kg−1 in healthy subjects. Whole blood glucose concentrations were measured contemporaneously and the rate of plasma glucose decline (mmol l−1 min−1) for each test was estimated from unlogged venous plasma glucose concentrations measured at 1 min intervals. The mean rates of plasma glucose decline for the 0.1 U kg−1 and 0.05 U kg−1 insulin doses were 0.26 mmol l−1 min−1 (n = 11, range = 0.17–0.41, intrasubject coefficient of variation (CV) = 9.4%) and 0.25 mmol l−1 min−1 (n = 6, range 0.19–0.46, intrasubject CV = 15.9%), respectively. Reversal of significant hypoglycaemia was necessary in one subject before 15 min post‐insulin. We found that: (1) venous sampling provides a reproducible measure of glucose uptake after insulin, (2) contemporaneous bedside glucose sampling identifies those at risk of significant hypoglycaemia during the ITT, and (3) the 0.1 U kg−1 dose response is more reproducible and no less safe than the half dose response. We conclude that the current ITT protocol would be made safer and simpler with the above modifications although further studies comparing venous with arterialized sampling are needed.

Diabetic microangiopathic complications in young Chinese diabetic patients: a clinic-based cross-sectional study.

Microangiopathic complications are major causes of morbidity and mortality in diabetic patients. We studied 150 consecutive young Chinese diabetic subjects attending the Prince of Wales Hospital Diabetes Center on their presence of diabetic microangiopathic complications and the relationships with other risk factors. All patients with aged younger than 40 years and had an age of onset of disease at younger than 35 years. Their known duration of diabetes was 57.2 +/- 5.0 months. Of these 150 patients, 50 (33.3%) had microangiopathic complications, 34 (22.7%) had albuminuria, 11 (7. 3%) had peripheral neuropathy, and 21 (14%) had retinopathy. Using multiple logistic regression analysis, albuminuria was independently associated with body-mass index and systolic blood pressure, peripheral neuropathy was associated with fasting plasma glucose and lower high-density lipoprotein cholesterol, and retinopathy was associated with duration of disease and fasting plasma glucose. In conclusion, there were high percentages of microangiopathic complications, particularly albuminuria, in our young Chinese diabetic patients. Obesity, high blood pressure, and poor glycemic control are important for these complications.

Effects of Providing Peer Support on Diabetes Management in People With Type 2 Diabetes

PURPOSE We examined the effects of participating in a “train-the-trainer” program and being a peer supporter on metabolic and cognitive/psychological/behavioral parameters in Chinese patients with type 2 diabetes. METHODS In response to our invitation, 79 patients with fair glycemic control (HbA1c <8%) agreed to participate in a “train-the-trainer” program to become peer supporters. Of the 59 who completed the program successfully, 33 agreed to be peer supporters (“agreed trainees”) and were each assigned to support 10 patients for 1 year, with a voluntary extension period of 3 additional years, while 26 trainees declined to be supporters (“refused trainees”). A group of 60 patients with fair glycemic control who did not attend the training program and were under usual care were selected as a comparison group. The primary outcome was the change in average HbA1c levels for the 3 groups from baseline to 6 months. RESULTS At 6 months, HbA1c was unchanged in the trainees (at baseline, 7.1 ± 0.3%; at 6 months, 7.1 ± 1.1%) but increased in the comparison group (at baseline, 7.1 ± 0.5%; at 6 months, 7.3 ± 1.1%. P = .02 for between-group comparison). Self-reported self-care activities including diet adherence and foot care improved in the trainees but not the comparison group. After 4 years, HbA1c remained stable among the agreed trainees (at baseline, 7.0 ± 0.2%; at 4 years: 7.2 ± 0.6%), compared with increases in the refused trainees (at baseline, 7.1 ± 0.4%; at 4 years, 7.8 ± 0.8%) and comparison group (at baseline, 7.1 ± 0.5%; at 4 years, 8.1 ± 0.6%. P = .001 for between-group comparison). CONCLUSIONS Patients with diabetes who engaged in providing ongoing peer support to other patients with diabetes improved their self-care while maintaining glycemic control over 4 years.

CHILDHOOD POISONING IN HONG KONG: EXPERIENCE OF THE DRUG AND POISONS INFORMATION BUREAU FROM 1988 TO 1992

Dr Cox (J. Paediatr. Child Health 1994; 30: 191 -2) will be pleased to know that the National Health and Medical Research Council (NH &MRC) has recommended that we adopt a two-dose strategy for measles, mumps, rubella (MMR) vaccine in 1994. The first dose is to be given to all children at the age of 12 months. The second dose will replace the existing rubella vaccination programme for teenage girls and is scheduled for all boys and girls aged 10-1 6 years. The vaccine will be supplied free to the States from July 1994. Some States have already made this change in the schedule, others are waiting to implement it after July 1. In 1993, nearly 4400 cases of measles were notified in Australia. This is by far the highest number for many years. Dr Cox was concerned about the proportion of teenagers among these cases and about the possibility of waning vaccine-induced immunity. While this may be responsible for some cases, by far the majority of cases of measles in Australia occur in children who have never been vaccinated. The introduction of the second dose of vaccine should not divert attention from the importance of increasing compliance for the first dose of MMR, which should be given promptly at the age of 12 months. Measles still has its highest morbidity and mortality in younger children. In the USA, in 1989, although only 37% of cases occurred in children under the age of 5 years, these caused 70% of the deaths.’ The new two-dose strategy for MMR is important and timely. However, we could just complacently revaccinate the vaccinated! More attention must be given to targeting immunization services to children who are disadvantaged. Immunization histories should be checked at every health care visit and deficiencies updated ‘on the spot’2 Health care providers should be familiar with the real contraindications to immunization and should not allow trivial reasons to postpone doses. One-third of the children presenting with measles in recent large measles outbreaks in the USA had had health care visits in the previous 6 weeks in which an opportunity had been missed to immunize them; these cases could have been p r e ~ e n t e d . ~ . ~ It is very likely that this is also occurring in Australia.

Health-Related Quality of Life in Chinese Patients with Type 2 Diabetes: An Analysis of the Joint Asia Diabetes Evaluation (JADE) Program

Objective: Diabetes is associated with impaired health-related quality of life (HRQoL) which predicts adverse clinical outcome. To examine clinical factors associated with HRQoL in a cross-sectional cohort of 14,826 Hong Kong Chinese patients with type 2 diabetes receiving outpatient care. Methods: Adult patients with type 2 diabetes who underwent comprehensive assessment of risk factors and complications using the web-based Joint Asia Diabetes Evaluation (JADE) Program also completed the EuroQol-5D (EQ-5D) questionnaire and visual analogue scale (VAS) for evaluation of HRQoL. Multiple linear regression analysis was used to identify clinical correlates with EQ-5D index and the association was expressed using β-coefficient whereby β>0 indicates positive correlation and β<0 indicates negative correlation. Results: More patients reported problems with pain/discomfort (24.8%) and anxiety/depression (20.3%) than other dimensions of mobility (7.1%), self-care (2.2%) and usual activities (4.3%). Age (β=-0.001), female gender (β=- 0.049), obesity (β=-0.007), hypoglycemia at least once monthly (β=-0.04), presence of cardiovascular disease (β=- 0.034), nephropathy (β=-0.014) and sensory neuropathy (β=-0.063) were independently correlated with lower EQ-5D index, while hypertension (β=0.017) and use of insulin (β=0.017) were correlated with higher EQ-5D index (p<0.05). Conclusion: In Hong Kong Chinese patients with type 2 diabetes, somatic and psychological complaints were common. Apart from demographic characteristics, risk factors, complications and treatment all influenced HRQoL.