Ethnic Chinese Subjects Research Articles

Qualitative Interviewing in Ethnic-Chinese Contexts: Reflections From Researching Taiwanese Immigrants in the United States

Qualitative interviewing is a broadly used method of data collection, but its discussions have rarely been situated in ethnic-Chinese contexts and immigrant communities. What factors are crucial for conducting effective interviews with ethnic-Chinese subjects? In what contexts do general principles not apply, thereby needing adjustments, and how? Reflecting on the experience of interviewing approximately 100 Taiwanese immigrants in the United States, I discuss the importance of mindfulness, cultural sensitivity, and triangulation. I argue that researchers need to be mindful of the potential effects of interviewers’ and interviewees’ structural positions on the interview process, quality, and outcomes. Cultural understanding is necessary when assessing ethical issues and designing interview questions. However, researchers also need to set aside their knowledge of ethnic-Chinese culture from time to time in order to capture the nuanced cultural meanings. Finally, conducting ethnographic observations helps researchers understand the lived contexts of subjects’ experiences and their varied interpretations. Using examples from two research projects, I illustrate significant factors that facilitate or hinder the proceeding of qualitative interviewing with ethnic-Chinese subjects. These reflections foster researchers’ understanding and practice of reflexivity at the crossroads of methods and ethnic culture.

Epidemiology of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) accounts for about 90% of the 456,000 incident esophageal cancers each year. Regions of high incidence include Eastern to Central Asia, along the Rift Valley in East Africa, and into South Africa. There are many causes of ESCC, which vary among regions. Early studies in France associated smoking cigarettes andheavy alcohol consumption with high rates of ESCC, but these factors cannot explain the high incidence in other regions. We discuss other risk factors for ESCC, including polycyclic aromatic hydrocarbons from a variety of sources, high-temperature foods, diet, and oral health and the microbiome-all require further research. A growing list of defined genomic regions affects susceptibility, but large genome-wide association studies have been conducted with ethnic Chinese subjects only; more studies are called for in the rest of Asiaand Africa. ESCC has been understudied, but growing infrastructure in more high-incidence countries will allow rapid progress in our understanding.

Hypertension subtypes modify metabolic response to thiazide diuretics.

Blood pressure (BP) and metabolic response to thiazide diuretics might be varied in patients with different hypertension subtypes and ethnicities. This study aimed to investigate the response of BP and metabolic profiles to short-term thiazide treatment in an Asian cohort with different hypertension subtypes. Serial ethnic Chinese nondiabetic subjects with hypertension were evaluated. After diet instruction and lifestyle modification for 2 weeks, patients who still had elevated systolic BP (SBP≥140 mmHg) and/or diastolic BP (DBP≥90 mmHg) were given 50 mg of hydrochlorothiazide daily for 2 weeks. The responses of BP and metabolic profiles were evaluated before and after treatment according to the patient's baseline BP subtype - isolated systolic hypertension (ISH), systo-diastolic hypertension (SDH) and isolated diastolic hypertension (IDH). Hydrochlorothiazide treatment significantly reduced the BP in all 92 patients (62 males, aged 45·7 ± 9·6 years), irrespective of their baseline BP subtypes. In patients with SDH (n = 39) or IDH (n = 40), hydrochlorothiazide treatment significantly increased serum adiponectin (P = 0·001 and 0·007, respectively) and reduced asymmetric dimethylarginine levels (P < 0·001, in both groups). Serum cholesterol (P = 0·027) and fasting blood sugar levels (P = 0·044) were significantly improved only in the IDH patients. Furthermore, IDH was independently associated with changes in fasting blood sugar (β = -11·178, P = 0·022) and cholesterol (β = -22·654, P = 0·027). The characteristics of the Asian hypertensive patients with diastolic hypertension can present a favourable metabolic response to the short-term hydrochlorothiazide treatment. The potential positive effect on cardiovascular risk should be validated in long-term studies in this diastolic type of hypertension.

Functional variants of 17q12-21 are associated with allergic asthma but not allergic rhinitis

Allergic rhinitis (AR) and asthma are common allergic conditions with a shared genetic component to their cause. The 17q12-21 locus includes several genes that have been linked to asthma susceptibility, but the role of this locus in AR is unclear. Asthma and AR in adults of Chinese ethnicity in Singapore are predominately caused by sensitization against house dust mites with a nearly complete penetrance of the allergen, which presents a unique opportunity for accurately identifying genetic associations with allergic diseases. We sought to define the functional role of 17q12-21 in patients with AR and allergic asthma. We asked whether single nucleotide polymorphisms (SNPs) in the 17q12-21 locus were associated with AR or asthma in a cohort of 3460 ethnic Chinese subjects residing in Singapore (1435 in the discovery phase and 2025 in the validation phase). Full-blood mRNA gene expression data, plasma IgE levels, and immune cell frequencies in peripheral blood were tested against the tag SNP genotypes. Luciferase assays were used to measure the effect of putative promoter SNPs on expression of the asthma-associated orosomucoid-like 3 gene (ORMDL3). Within 17q12-21, only the tag SNP rs8076131 was significantly associated with asthma (P = 8.53 × 10(-10); odds ratio, 0.6715), and AR status was independent of SNPs in this region. C-A alleles at rs8076131 resulted in significantly increased ORMDL3 expression in HEK293 cells in vitro relative to T-G alleles. Moreover, subjects with the risk genotype AA exhibited significantly higher total IgE levels and higher blood eosinophil counts than those with the lower-risk genotypes. The 17q12-21 locus has a strong genetic association with allergic asthma but not with AR. The polymorphic effect of this locus is attributed to the linkage set tagged by rs8076131, which affects the expression of ORMDL3, protein phosphatase 1, regulatory inhibitor subunit 1B (PPP1R1B), zona pellucida binding protein 2 (ZPBP2), and gasdermin B (GSDMB) and is correlated with high IgE levels and eosinophil counts in subjects bearing the risk genotype.

Association analysis of STK39, MCCC1/LAMP3 and sporadic PD in the Chinese Han population

With the completion of the Human Genome Project, GWAS have been widely used in exploring the genetic studies of complex diseases. A meta-analysis of datasets from five Parkinson's disease GWAS from the USA and Europe found 11 loci that surpassed the threshold for genome-wide significance (p<5×10−8), and five were newly identified loci (ACMSD, STK39, MCCC1/LAMP3, SYT11 and CCDC62/HIP1R). Another GWAS of the Ashkenazi Jewish population also identified loci in STK39 and LAMP3. Because the association between the STK39 and MCCC1/LAMP3 genes and PD was confirmed in different populations, we conducted a case-control cohort to clarify the association between the four single nucleotide polymorphism (SNP) loci (rs2102808 and rs3754775 in the STK39; rs11711441 and rs12493050 in the MCCC1/LAMP3) and PD in the Chinese Han population. Polymerase chain reaction and direct DNA sequencing analyses were used to detect the four variations in a case-control cohort comprised of 993 ethnic Chinese subjects. We found that in the detection of the rs11711441, there was a significant difference between ungrouped populations, early-onset PD, late-onset PD, male PD, female PD and the corresponding control group in allele and genotype frequency (p<0.001, OR<1). In the detection of the rs2102808, rs3754775 and rs12493050, ungrouped populations, early-onset PD, late-onset PD, male PD or female PD with the corresponding control group showed no significant difference in allele and genotype frequency (p>0.0125). Our findings suggested that the allele G of rs11711441 of the MCCC1/LAMP3 gene can decrease the risk of PD in Chinese population. No statistically significant difference in genotype frequency between cases and controls was observed for the other three SNPs.

The Short Form 36 English and Chinese versions were equivalent in a multiethnic Asian population

ObjectiveThe primary aim of this article was to evaluate measurement equivalence of the English and Chinese versions of the Short Form 36 version 2 (SF-36v2) and Short Form 6D (SF-6D). Study Design and SettingIn this cross-sectional study, health-related quality of life (HRQoL) was measured from 4,973 ethnic Chinese subjects using the SF-36v2 questionnaire. Measurement equivalence of domain and utility scores for the English- and Chinese-language SF-36v2 and SF-6D were assessed by examining the score differences between the two languages using linear regression models, with and without adjustment for known determinants of HRQoL. Equivalence was achieved if the 90% confidence interval (CI) of the differences in scores, due to language, fell within a predefined equivalence margin. ResultsCompared with English-speaking Chinese, Chinese-speaking Chinese were significantly older (47.6 vs. 55.5 years). All SF-36v2 domains were equivalent after adjusting for known HRQoL. SF-6D utility/items had the 90% CI either fully or partially overlap their predefined equivalence margin. ConclusionThe English- and Chinese-language versions of the SF-36v2 and SF-6D demonstrated equivalence.

Predicting the Glycemic Response to Gastric Bypass Surgery in Patients With Type 2 Diabetes

OBJECTIVETo find clinically meaningful preoperative predictors of diabetes remission and conversely inadequate glycemic control after gastric bypass surgery. Predicting the improvement in glycemic control in those with type 2 diabetes after bariatric surgery may help in patient selection.RESEARCH DESIGN AND METHODSPreoperative details of 154 ethnic Chinese subjects with type 2 diabetes were examined for their influence on glycemic outcomes at 1 year after gastric bypass. Remission was defined as HbA1c ≤6%. Analysis involved binary logistic regression to identify predictors and provide regression equations and receiver operating characteristic curves to determine clinically useful cutoff values.RESULTSRemission was achieved in 107 subjects (69.5%) at 12 months. Diabetes duration <4 years, body mass >35 kg/m2, and fasting C-peptide concentration >2.9 ng/mL provided three independent preoperative predictors and three clinically useful cutoffs. The regression equation classification plot derived from continuous data correctly assigned 84% of participants. A combination of two or three of these predictors allows a sensitivity of 82% and specificity of 87% for remission. Duration of diabetes (with different cutoff points) and C-peptide also predicted those cases in which HbA1c ≤7% was not attained. Percentage weight loss after surgery was also predictive of remission and of less satisfactory outcomes.CONCLUSIONSThe glycemic response to gastric bypass is related to BMI, duration of diabetes, fasting C-peptide (influenced by insulin resistance and residual β-cell function), and weight loss. These data support and refine previous findings in non-Asian populations. Specific ethnic and procedural regression equations and cutoff points may vary.

Predicting the glycemic response to gastric bypass surgery in patients with type 2 diabetes

OBJECTIVE To find clinically meaningful preoperative predictors of diabetes remission and conversely inadequate glycemic control after gastric bypass surgery. Predicting the improvement in glycemic control in those with type 2 diabetes after bariatric surgery may help in patient selection. RESEARCH DESIGN AND METHODS Preoperative details of 154 ethnic Chinese subjects with type 2 diabetes were examined for their influence on glycemic outcomes at 1 year after gastric bypass. Remission was defined as HbA 1c ≤6%. Analysis involved binary logistic regression to identify predictors and provide regression equations and receiver operating characteristic curves to determine clinically useful cutoff values. RESULTS Remission was achieved in 107 subjects (69.5%) at 12 months. Diabetes duration 35 kg/m 2 , and fasting C-peptide concentration >2.9 ng/mL provided three independent preoperative predictors and three clinically useful cutoffs. The regression equation classification plot derived from continuous data correctly assigned 84% of participants. A combination of two or three of these predictors allows a sensitivity of 82% and specificity of 87% for remission. Duration of diabetes (with different cutoff points) and C-peptide also predicted those cases in which HbA 1c ≤7% was not attained. Percentage weight loss after surgery was also predictive of remission and of less satisfactory outcomes. CONCLUSIONS The glycemic response to gastric bypass is related to BMI, duration of diabetes, fasting C-peptide (influenced by insulin resistance and residual β-cell function), and weight loss. These data support and refine previous findings in non-Asian populations. Specific ethnic and procedural regression equations and cutoff points may vary.

P061 Hyponatremia and Hypokalemia Induced by Antihypertensive Monotherapies in Clinical Practice: Risk Association Study among Ethnic Chinese Subjects

P061 Hyponatremia and Hypokalemia Induced by Antihypertensive Monotherapies in Clinical Practice: Risk Association Study among Ethnic Chinese Subjects

Low prevalence of functional bowel disorders in Iranian population using Rome III.

Dear Editor, The Research Institute for Gastroenterology and Liver Diseases in Shahid Beheshti Medical University (Iran) designed a cross-sectional household survey conducted from May 2006 to December 2007 in Tehran province, which aimed to find the prevalence of gastrointestinal symptoms and Functional disorders using Rome III criteria (1, 2). A total of 18180 adult persons drawn up randomly and interviewed using a valid questionnaire on the basis of Rome III (1, 2). The study revealed low rate of Functional Bowel Disorders (FBD) among urban population of Tehran province. In all, 1.1% met the Rome III criteria for Irritable Bowel Syndrome (IBS), 2.4% for functional constipation (FC) and 10.9% of the participants had any type of FBD (2). Our findings suggest that the FBD is less common in our study population than in previous similar studies. In two studies in Israel and one study in Canada, the prevalence of IBS was reported to be between 5.8–17.7% (3–5); In Turkey the overall prevalence of IBS was 6.3% respectively (6). In our study, the prevalence of IBS was significantly lower. A similar rate of IBS was found in a study conducted in Hong Kong among ethnic Chinese subjects with a prevalence of 4.1% (7). To our knowledge, because patients for our study were recruited from a general population, the selection biases that might apply to studies recruiting from a specialist clinic or hospital based study populations should not arise. Estimations may vary because of the specific questions used to establish a diagnosis of FBD (2). In addition, we remain uncertain about the ability of our study population to recall symptoms, over a 6-month period. In conclusion our study suggests a low rate of IBS in our study population. Attention should be paid to the influence of social and cultural factors upon symptom identification, recall and reporting when conducting studies to estimate the prevalence of IBS and FBD (8).

A shared susceptibility locus in PLCE1 at 10q23 for gastric adenocarcinoma and esophageal squamous cell carcinoma

We conducted a genome-wide association study of gastric cancer (GC) and esophageal squamous cell carcinoma (ESCC) in ethnic Chinese subjects in which we genotyped 551,152 single nucleotide polymorphisms (SNPs). We report a combined analysis of 2,240 GC cases, 2,115 ESCC cases, and 3,302 controls drawn from five studies. In logistic regression models adjusted for age, sex, and study, multiple variants at 10q23 had genome-wide significance for GC and ESCC independently. A notable signal was rs2274223, a nonsynonymous SNP located in PLCE1, for GC (P=8.40×10−9; per allele odds ratio (OR) = 1.31) and ESCC (P=3.85×10−9; OR = 1.34). The association with GC differed by anatomic subsite. For tumors located in the cardia the association was stronger (P=4.19 × 10−15; OR= 1.57) and for those located in the noncardia stomach it was absent (P=0.44; OR=1.05). Our findings at 10q23 could provide insight into the high incidence rates of both cancers in China.

Ethnic South Asian ischaemic stroke patients have a higher prevalence of a family history of vascular disease compared to age, gender and diabetes-matched ethnic Chinese subjects

Family history is a known non-modifiable risk factor of stroke. We aimed to compare the frequency of a family history of vascular disease between ethnic South Asian and Chinese stroke patients. We studied consecutive ethnic South Asian and Chinese ischaemic stroke patients matched for age, gender and presence of diabetes. Among the 152 matched pairs, ethnic South Asian ischaemic stroke patients had a higher frequency of vascular family history (IHD OR 3.465 p < 0.001; CVD OR 1.754 p = 0.059; and either IHD or CVD OR 2.169 p = 0.003) compared to matched ethnic Chinese patients, independent of past IHD history and stroke subtype. In the ethnic South Asian cohort, patients ≤ 60 years old had a higher frequency of a family history of IHD (37% vs 13%, p < 0.001), CVD (34% vs 15%, p = 0.005) and either IHD or CVD (52% vs 25%, p < 0.001) compared to those > 60 years. Family history of vascular disease is common among ethnic South Asian ischaemic stroke patients, particularly among those ≤ 60 years old. We postulate that the higher frequency of a vascular family history among ethnic South Asians compared to ethnic Chinese may be explained by genetic, environmental and lifestyle influences, or interactions between these factors.

Maximum mouth opening of ethnic Chinese in Taiwan

Background/purpose Maximum mouth opening (MMO) is a significant diagnostic reference for many clinical conditions. However, the number of relevant studies is limited, and the relationship between age and MMO has not yet been established. The purpose of this study was to measure and analyze the MMO of ethnic Chinese adults in Taiwan and to examine the possible relationship between age and MMO. Materials and methods A total of 1442 adult ethnic Chinese (Taiwanese) subjects aged 20–80 years (705 males, 737 females) were randomly selected. Subjects were divided into three age groups: 20–39 years (young), 40–59 years (middle), and ≥ 60 years (senior), and their maximum voluntary mouth opening was measured. Independent sample t test and one-way ANOVA followed by the post hoc Scheffe test were used to examine differences in MMO relative to sex and age groups. A simple linear regression model was used to estimate the relationship between MMO and age. Results The average MMO for sample subjects was 49.10 ± 6.30 mm, and the MMO of males (49.92 ± 6.55 mm) was significantly larger than that of females (48.32 ± 5.95 mm; P Conclusion Within the limits of this study, we concluded that both sex and age have significant influences on the MMO value of ethnic Chinese in Taiwan, and age is a significant predictor of MMO measurements.

Lack of awareness of heart disease and stroke among Chinese Canadians: Results of a pilot study of the Chinese Canadian Cardiovascular Health Project

According to Statistics Canada's 2001 census, the Chinese make up the largest (27.5%) visible minority population in Canada. The cardiovascular health information for this population is therefore important for the allocation of health care and promotion resources. In the present pilot study, the authors sought to define the degree of awareness and knowledge of cardiovascular disease, as well as their risk factors, among the Chinese Canadian population. A 16-item telephone survey was conducted among 1004 ethnic Chinese subjects (18 years of age and older) in the greater Toronto area of Ontario (n=503) and the greater Vancouver area of British Columbia (n=501) in February 2004. Among the respondents, 73% spoke Cantonese at home and 21% spoke Mandarin. Ninety-seven per cent were immigrants, and 53% had been in Canada for less than 10 years. A history of hypertension was reported in 9.2% of respondents, diabetes in 3.2% and high cholesterol in 14.5%. Thirty-two per cent and 40% of respondents were unable to name at least one symptom of heart attack or stroke, respectively, unaided. Thirty-two per cent and 35% of respondents named at least one incorrect symptom of heart attack and stroke, respectively. When asked about their immediate response in a hypothetical case of a heart attack or stroke, only 20% would have called 911. The present study is the first to address the awareness of cardiovascular health and disease among Chinese Canadians. These data suggest that Chinese Canadians have a relatively low awareness of the warning symptoms for common cardiovascular emergency situations. The findings presented here have important implications for the development of future health promotion and research initiatives targeted to visible minority populations in Canada.

Conversion to Dementia From Questionable Dementia in an Ethnic Chinese Population

We investigated the conversion rate and the risk factors for conversion to dementia from questionable dementia in 124 ethnic Chinese subjects with questionable dementia at a memory clinic of a university hospital. They were evaluated annually based on cognitive testing, the clinical dementia rating scale, and a psychiatrist's interview for depression and anxiety. Apolipoprotein E genotyping was performed on 111 of these questionable dementia subjects. All subjects were evaluated at least twice during the follow-up period of 20.4 +/- 12.4 months. During that period, 42 questionable dementia subjects were diagnosed as having Alzheimer's disease, with an annual conversion rate to dementia of 19.9%. Compared with the 82 nonconverters, the 42 converters were significantly older, had lower cognitive, depression, and anxiety scores, and a higher frequency of the apolipoprotein E epsilon4 allele. Cox regression analysis revealed that the Alzheimer's disease converters had lower scores for orientation, short-term memory, and anxiety, and a higher frequency of the apolipoprotein E epsilon4 allele than the nonconverters.

Nolatrexed dihydrochloride vs. doxorubicin, a clinical update of a multi-center randomized phase II study (014) in ethnic Chinese subjects with unresectable or metastatic HCC

4262 Background: Initial results of the original multi-center randomized Phase II study reported by Mok et al suggested that there was a 41% difference in the median survival of THYMITAQ (T) over doxorubicin (dox). We hereby present updated median survivals for the intent-to-treat (ITT) and evaluable populations within the same trial and a review of the patients' clinical characteristics in this particular trial. Methods: 54 patients were randomized in a 2:1 fashion to receive either T (37) or dox (17), respectively. 44 subjects who completed 2 or more cycles of either drug were considered for the evaluable population. The clinical presentation of these patients is reviewed. Results: For the ITT population, the median survival for the T arm was 19.8 wks and the dox arm was 14.8 wks, which represents a 34% increase in median survival in favor of T. The evaluable population for T produced a median survival of 23.4 wks compared to a median survival of 15.4 wks for dox, which represents a 52% increase in survival in favor of T. Of the 54 patients in the trial, 32 (59%) had cirrhosis, 22 of these in the T arm and 10 in the dox arm. In addition, 26 (48%) had portal invasion; 42 (78%) were hepatitis carriers. Conclusions: As noted in the previous communication of study 014 there is a difference in median survival in favor of T vs. dox. Although the p value (0.8519) on median survival was not significant; there was clinical benefit in terms of survival, particularly evident when the patient characteristics of each treatment arm are reviewed. Cirrhosis, portal invasion and hepatitis carriers have the worst outcomes in terms of survival in HCC. Regardless of these bad prognosis factors patients treated with T did better in terms of survival than those treated with dox (by 34% in ITT population and by 52% in evaluable population). The randomization in the current ETHECC (Evaluation of T in HCC) Phase III study is based on CLIP scores and Karnofsky PS which allows for an equal distribution of patients characteristics at randomization. The primary endpoint of ETHECC is overall survival in the treatment of unresectable HCC. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration EXIMIAS Pharmaceutical Corp.

Nolatrexed dihydrochloride vs. doxorubicin, a clinical update of a multi-center randomized phase II study (014) in ethnic Chinese subjects with unresectable or metastatic HCC

4262 Background: Initial results of the original multi-center randomized Phase II study reported by Mok et al suggested that there was a 41% difference in the median survival of THYMITAQ (T) over doxorubicin (dox). We hereby present updated median survivals for the intent-to-treat (ITT) and evaluable populations within the same trial and a review of the patients' clinical characteristics in this particular trial. Methods: 54 patients were randomized in a 2:1 fashion to receive either T (37) or dox (17), respectively. 44 subjects who completed 2 or more cycles of either drug were considered for the evaluable population. The clinical presentation of these patients is reviewed. Results: For the ITT population, the median survival for the T arm was 19.8 wks and the dox arm was 14.8 wks, which represents a 34% increase in median survival in favor of T. The evaluable population for T produced a median survival of 23.4 wks compared to a median survival of 15.4 wks for dox, which represents a 52% increase in survival in favor of T. Of the 54 patients in the trial, 32 (59%) had cirrhosis, 22 of these in the T arm and 10 in the dox arm. In addition, 26 (48%) had portal invasion; 42 (78%) were hepatitis carriers. Conclusions: As noted in the previous communication of study 014 there is a difference in median survival in favor of T vs. dox. Although the p value (0.8519) on median survival was not significant; there was clinical benefit in terms of survival, particularly evident when the patient characteristics of each treatment arm are reviewed. Cirrhosis, portal invasion and hepatitis carriers have the worst outcomes in terms of survival in HCC. Regardless of these bad prognosis factors patients treated with T did better in terms of survival than those treated with dox (by 34% in ITT population and by 52% in evaluable population). The randomization in the current ETHECC (Evaluation of T in HCC) Phase III study is based on CLIP scores and Karnofsky PS which allows for an equal distribution of patients characteristics at randomization. The primary endpoint of ETHECC is overall survival in the treatment of unresectable HCC. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration EXIMIAS Pharmaceutical Corp.

Ethnic and environmental differences in various markers of dietary intake and blood pressure among Chinese Han and three other minority peoples of China: results from the WHO Cardiovascular Diseases and Alimentary Comparison (CARDIAC) Study.

Our aim was to examine differences in dietary intake and blood pressure (BP) and their associations in four different ethnic Chinese populations, the Han, the Uygur, the Kazak and Tibetan subjects. This study used a sub-database of the Chinese sample of the WHO-Cardiovascular Diseases and Alimentary Comparison (CARDIAC) Study. The WHO-CARDIAC Study was a multicenter cross-sectional study. In each center, 100 men and 100 women aged 48-56 years were selected at random from the local population. Various markers of dietary intake and their relation with BP were studied. The results of the present study indicated the following. 1) There were significant differences in mean BP and prevalence rates of hypertension, with both being higher in the Kazak and Tibetan subjects than in Han and Uygur subjects. 2) The highest mean body mass index (BMI) was observed in the Kazak subjects, while the highest 24-h urinary sodium (Na) and sodium to potassium (Na/K) ratio excretion were observed in the Tibetan subjects. There were also significant differences in other factors, such as magnesium, 3-methylhistidine (3MH) (a biological marker of animal protein intake) and taurine (a biological marker of seafood intake) excretion levels among the four ethnic peoples. 3) In general, BMI, Na and/or Na/K ratios were positively, and 3MH/creatinine and taurine/creatinine ratios were negatively associated with BP. 4) After adjustment for age, sex and potassium, subjects with obesity (BMI > or =26 kg/m2) had significantly higher relative risk of being hypertensive (HT) than those with BMI<26 kg/m2 in the Han, Uygur and Kazak populations; and subjects with elevated sodium excretion (Na > or =244 mmol/day) had significantly higher relative risk of being HT than those with Na<244 mmol/day in the Han, Uygur and Tibetan populations. In conclusion, mean BP and prevalence rates of hypertension were significantly different among the four ethnic groups. These differences are likely to be due, at least in part, to the differences in several diet-related factors, which in turn are associated with culture and environmental differences. Different health promotion strategies might thus be emphasized in different populations.

In vivo determinants of arterial biophysical properties: methodological considerations: (Reply to Lehmann and Gosling)

Dear Sir,We do not believe that there is much value in continuing a correspondence now only vaguely related to a study published more than 2 years ago [1]. The report in question was a cross sectional study of a large group of ethnic Chinese subjects in whom ultrasound of the aorta with conventional cardiac echocardiographic equipment and pulse wave velocity were used to examine arterial properties. No interventions took place or were planned subsequent to the initial investigation. We prefer to rely on conventional peer review rather than publish findings in letters and commentaries not generally subject to such evaluation. There are, however, two points we wish to make on this occassion. Firstly to correct the impression that the use of conventional echocardiography equipment and transthoracic techniques to assess the stiffness of the proximal aorta is a technical approach limited to ourselves. It has been used in a number of peer reviewed articles from other groups [2–9]and we refer interested readers to these for further information, including data on measurement variability. It also appears that our recent comments on the use of pulse wave velocity [10]have been somewhat misconstrued. We did not criticise this technique but stressed that it was one of a number of techniques available and stated `that techniques are available which, in specific cases, may be more pathophysiologically relevant than measurement of PWV'. We still believe this to be the case.