Y. T. Mak

Low density lipoprotein receptor related protein gene exon 3 polymorphism association with Alzheimer's disease in Chinese

Since apolipoprotein E4 (apoE4) is the major genetic risk for late onset Alzheimers disease (AD), proteins that interact with apoE might be involved in AD pathogenesis. Low density lipoprotein receptor related protein (LRP) is an apoE receptor in the brain. In exon 3 of the LRP gene a polymorphism was found to be underrepresented in AD compared to normal Caucasian subjects (N). We examined this polymorphism in Chinese AD and N subjects. The polymorphism frequency in N was roughly half that reported for Caucasians. Compared to N, the frequency was significantly decreased in pathologically diagnosed, but not in clinically diagnosed AD patients. Thus, the role of the LRP exon 3 polymorphism in AD has now been demonstrated in two ethnic groups, suggesting the importance of LRP in AD pathogenesis.

Apolipoprotein E genotype and Alzheimer's disease in Hong Kong elderly Chinese

Article abstract-We studied the apolipoprotein E (apoE) allele frequencies in 65 Chinese patients with late-onset Alzheimers disease (AD) and 82 age- and sex-matched controls. The apoE epsilon 4 allele frequency was significantly higher in the AD group than in the control group (0.169 versus 0.067, p < 0.01). There were five homozygotes for epsilon 4 in the AD group but none among the controls. The odds ratio for AD was 1.6 for epsilon 4 heterozygotes. The age at onset was lower with the presence of the epsilon 4 allele and higher with the epsilon 2 allele, although neither of these differences reached statistical significance. The association between apoE alleles and AD previously reported in Caucasian populations was also present in this first reported study in Chinese.However, the lower epsilon 4 frequency in the Chinese population is compatible with previous reports of lower prevalence of AD compared with the prevalence of multi-infarct dementia. NEUROLOGY 1996;46: 146-149

The prevalence of diabetes mellitus and an assessment of methods of detection among a community of elderly Chinese in Hong Kong

SummaryThis study provides information on the prevalence of diabetes mellitus in a group of elderly Chinese subjects aged 60 and above living in the community in Hong Kong, and investigates the sensitivity of the urine sugar, random blood glucose, glycosylated haemoglobin, and fructosamine measurements compared to a glucose tolerance test in screening for diabetes mellitus in this population. Four hundred twenty-seven subjects aged 60 and above were studied. The National Diabetes Data Group Criteria were used for the diagnosis of diabetes. Those with a random blood glucose exceeding 12.5 mmol/l were considered diabetic, and all of these patients had glycosuria together with elevated total glycosylated haemoglobin and fractosamine concentrations. A diagnostic 75 g oral glucose tolerance test was performed on patients with one or more of the following abnormalities: glycosuria, random plasma blood glucose 7.8 mmol/l to 12.5 mmol/l, glycosylated haemoglobin 8.5%, and fructosamine 2.20 mmol/l. By these criteria, the prevalence of diabetes in this community was found to be 9.8%. An elevated random glucose greater than 11.1 mmol/l proved to be the only specific method of screening and glycosuria was found to be at least as good as fractosamine and HbA1. However, HbA1 is more sensitive than random glucose, glycosuria or fructosamine in detecting impaired glucose tolerance. On the basis of this study, a higher reference range for glycosylated haemoglobin for the elderly alone is also suggested (5.74–9.34%).

Biochemical predictors of short term mortality in elderly residents of chronic care institutions.

A survey of 208 elderly subjects living in four long term care institutions was undertaken over three months to identify nutritional and other variables that could be used to predict mortality during the subsequent three months. There were 58 men (mean age (SD) 75.6 (9.6) years) and 150 women (79.5 (8.4) years). Twenty nine subjects died (12 men and 17 women) within three months of completing the study. Twenty eight out of 57 variables differed significantly between those who died and those who survived. Subjects who died had lower systolic blood pressure, poorer intake of protein calories, lower concentrations of haemoglobin, plasma retinol, zinc, total cholesterol, and higher albumin adjusted plasma calcium concentrations. Stepwise regression analysis identified five variables that predicted mortality: plasma fructosamine; transferrin; glycosylated haemoglobin; prealbumin; and haemoglobin. The sensitivity, specificity, and predictive values of the discriminant function score using 0 as the demarcation between survivors and non-survivors were 75%, 97%, and 95%, respectively. This score could therefore be used to identify those most in need of nutritional support.

Nutritional status of general medical patients—influence of age and disease

Abstract Arm anthropometry and biochemical indices of protein energy, vitamin, and mineral status were estimated in 294 patients admitted to the general medical wards of a district general hospital over a one-month period. Elderly patients, and those with infections, malignancies, heart failure, and chronic obstructive airways disease had poorer nutritional status. The striking abnormalities were poor protein energy and plasma retinol status. Hospital patients aged 60 years and over had poorer protein energy and vitamin status (with the exception of thiamine and riboflavin) compared to those living in the community and long-term care institutions. Increased awareness of nutritional problems in the above categories of patients would result in improved nutritional support and possibly would accelerate recovery or reduce mortality.

Vitamin nutritional status in elderly Chinese subjects living in chronic care institutions

Abstract Dietary intake and blood levels of some vitamins were assessed in 208 elderly subjects (mean age 78.4±8.6 years) living in four chronic care institutions in Hong Kong. Compared to elderly free-living subjects, both men and women had lower intakes of thiamine, nicotinic and ascorbic acid, while in addition men had lower intakes of riboflavin and retinol equivalent. Plasma folate and 25 hydroxyvitamin D (25 OHD) concentrations were lower among both men and women in institutions. Men also had lower plasma retinol concentration and poorer thiamine status, while women had lower plasma ascorbic acid and cyanocobalamin concentrations. Vitamin supplementation and ability to self feed did not greatly affect vitamin nutritional status in this group of institutionalized subjects. Compared to elderly Caucasians living in chronic care institutions, elderly Chinese had poorer riboflavin, pyridoxine, nicotinic acid, vitamin A, and ascorbic acid status, but better cyanocobalamin, folic acid, and vitamin D status. Different dietary habits and quantity of sunshine probably contribute to these differences. Improvement in the vitamin nutritional status of elderly Chinese in chronic care institutions is desirable.

Prediction of mortality in patients in acute medical wards using basic laboratory and anthropometric data.

The value of anthropometric and biochemical indices in predicting short-term mortality among patients in general medical wards was assessed in 294 patients admitted consecutively to a district hospital over a one month period. Using a stepwise logistic regression model and supported by the linear discriminant analysis method, mortality within 3 months could be predicted with sensitivity of 83% and specificity of 84% using the following variables: sex, functional ability, urea, total protein, alkaline phosphatase and albumin-adjusted calcium. Addition of anthropometric values and biochemical nutritional indices did little to improve the accuracy of the prediction, contrary to previous findings among surgical patients and elderly residents of long-term care institutions.

Intake and blood levels of some minerals in an elderly Chinese population

Twenty-four hour intakes of potassium, calcium, and iron, and plasma concentration of potassium, copper and zinc were determined in a cluster sample of 400 apparently healthy subjects aged 60 years and over living in the community. Potassium and calcium intakes were lower in older men and lower in men compared to women. Both were much lower than intakes reported among Caucasian elderly, while iron intakes are comparable. Plasma potassium concentration was lower than values from studies of all ages and from studies of Caucasian elderly subjects. Copper and zinc concentrations were comparable to published values for adults of all ages. The significance of low potassium and calcium intake among elderly subjects in the population is discussed.

Serum vitamin E concentrations in adult-onset spinocerebellar degeneration.

improvement in both hand and leg tremor, but the beneficial effect was only sustained for about 3 months. Clonazepam was started at a dose of 2 mg/day and increased to 4 mg/ day over a 2-month period. Amplitude and frequency of hand and leg tremor was measured objectively (see ref 8 for method) throughout incremental dosing and again 6 months after reaching the optimal dose. Leg tremor showed a marked dose-related decrease in amplitude on clonazepam by objective measures (fig) and by the patients own reports. Hand tremor was unchanged, objectively and subjectively, by clonazepam. Involvement of the legs is not uncommon in essential tremor. In a survey of 185 consecutive essential tremor patients we found leg tremor to be present in 29 (15-7%) although isolated leg tremor (that is, in the absence ofhand tremor) was found in only 4 (2-2%) (unpublished data). Essential tremor of the legs is generally present during any voluntary muscle activity but is often exacerbated on standing. In a single case study, Thompson et al2 noted that 16 Hz orthostatic tremor of the legs was not present during all types of voluntary muscle activity thus tremor occurred when standing or pressing the feet against the floor as if preparing to stand, but was absent when the patient was seated and extending the leg horizontally against gravity. The authors concluded that orthostatic tremor arose from an abnormality in the organisation of the motor program for standing. Deuschl et al,3 however, described a patient with a similar, 16 Hz leg tremor which was present during all kinds ofmuscle activation in sitting, lying or standing positions. The pathophysiology of essential tremor and orthostatic tremor is not known. Interpatient variability in the clinical appearance of essential tremor and in its responsiveness

Erythrocyte membrane fatty acid profile in chinese children

Abstract Erythrocyte membrane fatty acid profiles, a good indicator of dietary fatty acid intake were measured in seventy-two Hong Kong Chinese children at the age of five. Results were compared to forty-eight of their mothers and ninety-one Irish children with mean age of 40 months. Chinese children were shown to have significantly higher level of saturated fatty acids and monounsaturated fatty acids but lower level of polyunsaturated fatty acids than the Irish children. Mothers of the Chinese children showed a resemblance of their childrens fatty acid profiles. Findings were compatible with the present dietary practices of Hong Kong people: large quantities of meat and lesser quantities of vegetables consumption.