A population-based study of the prevalence and associated factors of diabetes mellitus in southern Taiwan

Autonomic modulation and the risk of dementia in a middle-aged cohort: A 17-year follow-up study

BACKGROUND

Altered autonomic modulation, measured by heart rate variability (HRV), has been found to be associated with dementia risk in the elderly. However, long-term follow-up study evaluating the association between autonomic modulation from middle-age and the incidence of dementia has been limited.

METHODS

This retrospective cohort analyzed data from Taiwan's National Health Insurance Database covering the period from 2001 to 2017, with a linkage to citywide health examinations conducted by Tainan Metropolitan City, Taiwan. We included subjects aged 45-64 years. The mean follow-up period was 15.75 ± 3.40 years. The measurements of HRV included resting heart rate, high frequency (HF), low frequency (LF), standard deviation of normal-to-normal R-R intervals (SDNN), ratio between the 30th and 15th R-R interval after standing up from the supine position (30/15 ratio), ratio between the R-R intervals during expiration and inspiration, and the ratio between the high- and low-frequency components (LF/HF). The main study outcome was the incidence of dementia. We performed multivariable Cox proportional hazard regression models to compare the risk of dementia among different HRV subgroups.

RESULTS

We included 565 participants with a mean age of 53 (SD: 6) years, of whom 44% were male. The risk of dementia was significantly increased in association with lower parasympathetic HRV modulation, including SDNN (HR: 3.23, 95% CI: 1.55-6.73) and 30/15 ratio (HR: 3.52, 95%CI: 1.67-7.42). Moreover, the risk of dementia was increased in subjects with higher LF/HF ratios (HR: 2.05, 95% CI: 1.12-3.72).

CONCLUSIONS

Lower parasympathetic activity and higher sympathetic-vagal imbalance in middle-age were associated with dementia risk.

The association between the Lie scale of the Maudsley personality inventory and striatal dopamine D2/D3 receptor availability of healthy Chinese community subjects

The present study examined the relationship between the Lie scale scores and striatal D2/D3 receptor availability with respect to the cerebellum in 42 healthy community volunteers in Taiwan using single photon emission computed tomography (SPECT) with [123I]iodo-benzoaminde (IBZM). Even after controlling of age and educational level, subjects' Lie scale scores of the Maudsley personality inventory correlate negatively with D2/D3 receptor availability. Individual with higher Lie scale scores may have higher impulsivity due to lower dopaminergic availability.

Epidemiological evidence of increased waist circumference, but not body mass index, associated with impaired baroreflex sensitivity

Although an inverse relationship between body mass index (BMI) and baroreflex sensitivity (BRS) was found, the effect of waist circumference (WC) on BRS is still inconclusive. The contradictory results of previous studies may be related to the heterogeneity and relatively small sample size of the subjects examined. The aim of this population-based study was to investigate whether the influence of increased WC is more detrimental to BRS than BMI. A total of 760 community dwellers were recruited and they were classified into Q1 (n = 189), Q2 (n = 183), Q3 (n = 192) and Q4 (n = 196) groups, based on WC quartiles. Spontaneous BRS was determined by spectral α coefficient method. Valsalva ratio was the longest RR interval after release of Valsalva maneuver divided by the shortest RR interval during maneuver. Cardiac autonomic function was calculated by power spectrum of heart rate in low and high frequency (LF, 0.04-0.15 Hz; HF, 0.15-0.40 Hz), and LF/HF ratio in supine position for five minutes. There were significant differences in spontaneous BRS and Valsalva ratio among different WC groups. In multivariate analysis, obesity was inversely associated with spontaneous BRS and Valsalva ratio. However, these inverse relationships became insignificant after further adjustment for WC quartiles. In contrast, Q4 vs. Q1, Q3 vs. Q1 and Q2 vs. Q1 of WC were inversely related to spontaneous BRS. Q4 vs. Q1 and Q3 vs. Q1 of WC were negatively associated with the Valsalva ratio. In conclusion, increased and even high-normal WC had a stronger adverse effect on BRS than BMI, independent of cardio-metabolic risk factors.

Cardiotrophin-1 is inversely associated with obesity in non-diabetic individuals

Cardiotrophin-1 is known to be a key regulator of energy homeostasis, as well as glucose and lipid metabolism in vivo. However, there are inconsistent results of the association between cardiotrophin-1 and obesity in humans, possibly confounded by hyperglycemia. Therefore, the aim of this study was to investigate the relationships among cardiotrophin-1 levels, overweight and obese individuals without diabetes in a Chinese population. The median (inter-quarter range) serum cardiotrophin-1 levels were 447.9 (230.9, 913.9), 350.6 (201.1, 666.5), and 288.1 (162.3, 572.4) pg/ml in non-diabetic subjects who were of normal weight (n = 522), overweight (n = 203), and obese (n = 93), respectively (trend test p < 0.001). Subjects who were overweight and obese had significantly lower cardiotrophin-1 levels than those with normal weight. The multivariate linear regression analyses showed that overweight (beta = −338.718, 95% CI = −552.786 ~ −124.651, p < 0.01), obese (beta = −530.275, 95% CI = −832.967 ~ −227.583, p < 0.01), and smoking (beta = −377.375, 95% CI = −654.353 ~ −100.397, p < 0.01) were negatively related to cardiotrophin-1 after adjusting for age, gender, HOMA-IR, hypertension, total cholesterol, HDL, triglyceride, eGFR, ALT, and alcohol drinking. The results of this study provided epidemiological evidence that non-diabetic subjects who were overweight or obesity had significantly lower cardiotrophin-1 concentrations than those with normal weight, and both obesity and being overweight were inversely associated with cardiotrophin-1 levels.

Type 2 diabetes and its correlates among adults in Bangladesh: a population based study

BACKGROUND

Type 2 diabetes is one of the most prevalent non-communicable diseases in Bangladesh. However, the correlates of type 2 diabetes among adults in Bangladesh remain unknown. We aimed to investigate the correlates of type 2 diabetes among the adults in Bangladesh.

METHODS

We conducted a cross-sectional study using data from the nationally representative 2011 Bangladesh Demographic and Health Survey. A random sample of 7,543 (3,823 women and 3,720 men) adults of age 35 years and older from both urban and rural areas, who participated in the survey was included. Diabetes was defined as having a fasting plasma blood glucose level of ≥ 7 mm/L or taking diabetes medication during the survey. Hypothesized factors, e.g., age, sex, education, place of residence, social status, body mass index, and hypertension were considered in the analyses. Multivariable logistic regression models were used to identify the important correlates of type 2 diabetes.

RESULTS

Among the respondents, the overall prevalence of diabetes was 11 %, and the prevalence was slightly higher in women (11.2 %) than men (10.6 %). Respondents with the age group of 55-59 years had higher odds of having diabetes (odds ratios (OR) = 2.37, 95 % confidence interval (CI): 1.76-3.21) than the age group of 35-39 years. Moreover, respondents who had higher educational attainment (OR = 1.67, 95 % CI: 1.18-2.36) and higher social status (OR = 2.01, 95 % CI: 1.50-2.70) had higher odds of having diabetes than the respondents with no education and lower social status, respectively. We also found socioeconomic status, place of residence (rural or urban), regions of residence (different divisions), overweight and obesity, and hypertension as significant correlates of type 2 diabetes in Bangladesh.

CONCLUSIONS

Our study shows that older age, higher socioeconomic status, higher educational attainment, hypertension, and obesity were found to be significant correlates of type 2 diabetes. Need-based policy program strategies including early diagnosis, awareness via mass media, and health education programs for changing lifestyles should be initiated for older age, wealthy, and/or higher educated individuals in Bangladesh. Moreover, area-specific longitudinal research is necessary to find out the underlying causes of regional variations.

Prevalence of diabetes mellitus and impaired fasting glucose, associated with risk factors in rural Kazakh adults in Xinjiang, China

OBJECTIVE

This study aimed to estimate the prevalence of diabetes mellitus (DM) and impaired fasting glucose (IFG) in a Kazakh population aged ≥18 years living in the YiLi District of Xinjiang, China and to evaluate the associated risk factors of diabetes.

METHODS

Randomly selected adults, living for at least 6 months in the YiLi District in Xinjiang had their clinical characteristics and standard blood chemistries measured. DM and IFG were defined according to WHO 1999 criteria. The adjusted odds ratio (ORs) and 95% confidence intervals were calculated for the association of diabetes risk factors in multivariate logistic regression models.

RESULTS

A total of 3919 subjects were randomly selected. The age-and gender-standardized prevalence of DM and IFG were 5.9% and 10.0%, respectively. The prevalence of DM and IFG increased with age and BMI. Prevalence of 7.4%, 12.2% in males and 4.9%, 8.6% in females for DM and IFG. Compared by sex, prevalence of DM and IFG was higher in males. Prevalence of 3.4%, 8.1% in normal, 6.7%, 11.9% in overweight and 12.0%, 13.0% in obesity for diabetes and IFG. In the multivariable logistic models, male sex, older age, unmarried, overweight, obesity, hypertension, triglycerides and smoking were all significantly associated with an increased risk of diabetes.

CONCLUSIONS

The prevalence of DM and IFG among minorities was lower than the overall national level both in men and women (9.7% in total, 10.6% in males, 8.8% in females), and also lower than among the Han ethnicity (9.26%) which predominates in China today.

The geography of diabetes among the general adults aged 35 years and older in Bangladesh: recent evidence from a cross-sectional survey

Objective

To report geographical variations of sex-specific diabetes by place of residence (large cities/city corporations, small towns/other urban areas, rural areas) and region of residence (divided into seven divisions) among general adults (35+ years of age) in Bangladesh.

Methods

The recent cross-sectional data, extracted from the nationally representative Bangladesh Demographic and Health Survey 2011, was used. A total of 3,720 men and 3,823 women aged 35+ years, who participated in the fasting blood sugar testing, were analysed. Any person with either fasting plasma glucose level (mmol/L) ≥7.0 or taking medication for diabetes was considered as a person with diabetes.

Results

The prevalence of diabetes was 10.6% in men and 11.3% in women. Bivariable analyses indicated significant variations of diabetes by both geographical variables. The prevalence was highest in city corporations (men 18.0%, women 22.3%), followed by small towns (men 13.6%, women 15.2%) and rural areas (men 9.3%, women 9.5%). Regional disparities in diabetes prevalence were also remarkable, with the highest prevalence in Chittagong division and lowest prevalence in Khulna division. Multivariable logistic regression analyses provided mixed patterns of geographical disparities (depending on the adjusted variables). Some other independent risk factors for diabetes were advancing age, higher level of education and wealth, having TV (a proxy indicator of physical activity), overweight/obesity and hypertension.

Conclusions

Over 10% of the general adults aged 35 years and older were having diabetes. Most of the persons with diabetes were unaware of this before testing fasting plasma glucose level. Although significant disparities in diabetes prevalence by geographical variables were observed, such disparities are very much influenced by the adjusted variables. Finally, we underscore the necessities of area-specific strategies including early diagnosis and health education programmes for changing lifestyles to reduce the risk of diabetes in Bangladesh.

Gastric Helicobacter pylori infection associated with risk of diabetes mellitus, but not prediabetes

BACKGROUNDS AND AIM

The association between Helicobacter pylori infection and diabetes was inconsistent in previous studies. Moreover, there are no studies on the relationship between H. pylori infection and prediabetes in the literature. The aim of this study is thus to assess the association of Helicobacter infection, diagnosed by pathology from gastric biopsy, with diabetes and prediabetes.

METHODS

This cross-sectional study included 1285 subjects aged 19-85 who underwent esophagogastroduodenoscopy and gastric biopsy during health examinations at National Cheng Kung University Hospital from 2000 to 2009. Subjects were divided into three groups, including normal glucose tolerance, prediabetes, and diabetes. Diabetes and prediabetes were assessed according to the American Diabetes Association diagnostic criteria. Gastric Helicobacter infection was an independent variable. Chi-square tests, analysis of variance, and multinomial logistic regression models were used to analyze the effects of Helicobacter infection on the risk of diabetes and prediabetes while controlling for age, lifestyle, pathological conditions, and laboratory variables.

RESULTS

There were significant differences in the prevalence of gastric Helicobacter infection among the three groups. The results of multivariate analysis showed that age, obesity, family history of diabetes, hypertension, and hypertriglyceridemia were significantly related to both prediabetes and diabetes. Helicobacter pylori infection was positively associated with diabetes (odds ratio [OR] 1.42, 95% confidence interval [CI] 1.01-2.01), but not prediabetes (OR 1.02, 95% CI 0.77-1.36), in addition to male gender, education level (≤ 9 vs > 12 years), pre-hypertension, and low high-density lipoprotein cholesterol.

CONCLUSIONS

Gastric H. pylori infection is associated with diabetes, but not prediabetes.

Impaired baroreflex sensitivity in subjects with impaired glucose tolerance, but not isolated impaired fasting glucose

Impaired baroreflex sensitivity (BRS) is associated with adverse cardiovascular outcomes. There are currently no studies on BRS changes in subjects with different glycemic statuses, including normal glucose tolerance (NGT), isolated impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and newly diagnosed diabetes (NDD). The aim of this study was to investigate the effects of NDD, IGT and isolated IFG on BRS, based on a community-based data. A total of 768 subjects were classified as NGT (n = 498), isolated IFG (n = 61), IGT (n = 126) and NDD (n = 83). Spontaneous BRS was determined by the spectral α coefficient method, i.e., the square root of the ratio between the power of the RR interval and the power of systolic blood pressure in the LF frequency region (0.04-0.15 Hz) after the subjects had rested in a supine position for 5 min. Valsalva ratio was calculated as the longest RR interval after release of the Valsalva maneuver, divided by the shortest RR interval during the maneuver. As compared with NGT subjects, NDD (p = 0.039) and IGT (p = 0.041) subjects had a reduced spontaneous BRS in multivariate analysis based on analysis of covariance. NDD subjects exhibited a lower Valsalva ratio than NGT subjects (p = 0.043). However, there were no significant differences in spontaneous BRS and Valsalva ratio between subjects with isolated IFG and NGT. In conclusion, NDD and IGT subjects had an impaired BRS as compared to NGT subjects. However, reduced BRS was not apparent in subjects with isolated IFG.

The relationship between different glycemic statuses and colon polyps in a Taiwanese population

BACKGROUND

While diabetes is considered as a risk factor for colorectal cancer, there are few studies that address the association between glycemic statuses and different colon polyps, ranging from non-neoplastic polyps to advanced adenomatous polyps.

METHODS

A total of 6,348 participants, consisting of 3,777 men and 2,571 women, with a mean age of 50.5 years, were included for final analysis after excluding subjects with a past history of colorectal cancer, colon polyps/polypectomy, familial adenomatous polyposis, and colorectomy, or missing data. Diabetes and pre-diabetes were defined using the 2011 American Diabetes Association criteria. Subjects were classified into four groups: polyp-free, non-neoplastic polyps, non-advanced and advanced adenomatous polyps.

RESULTS

There were significant differences in the prevalence of diabetes and pre-diabetes among groups with different kinds of colon polyps. In addition, significant differences were also noted in age, total cholesterol, body mass index, triglyceride, high density lipoprotein-cholesterol, fasting plasma glucose, and the prevalence of male gender, hypertension, obesity, current smoking and alcohol drinking among groups. In the multinomial logistic regression analyses, diabetes was related to both non-advanced and advanced adenomatous polyps, while pre-diabetes was only related to non-advanced adenomatous polyps. In addition, age ≥65 years and male gender were associated with both non-advanced and advanced adenomatous polyps, while hypertension and current smoking were independently related to advanced and non-advanced adenomatous polyps, respectively.

CONCLUSIONS

Diabetes, but not pre-diabetes, was associated with a higher risk of advanced adenomatous polyps. In addition, both diabetes and pre-diabetes were important correlates of non-advanced adenomatous polyps.

Cardiac autonomic function and insulin resistance for the development of hypertension: a six-year epidemiological follow-up study

BACKGROUND AND AIMS

To explore the impact of cardiac autonomic function (CAF) and insulin resistance (IR) on incident hypertension.

METHODS AND RESULTS

In 1996, 1638 subjects finished baseline examination, which included anthropometry, blood pressures, CAF, blood biochemistry, plasma insulin, urine examination and electrocardiogram. CAF included standard deviation of normal-to-normal intervals or RR intervals (SDNN), low- and high-frequency power spectrum (LF and HF), and LF/HF ratio at supine for 5 min, the RR interval changes during lying-to-standing maneuver, and the ratio between the longest RR interval during expiration and the shortest RR interval during inspiration (E/I ratio). We used homeostasis model assessment to define beta cell function (HOMA-B) and insulin resistance (HOMA-IR). In total, 992 non-hypertensive participants completed the follow-up assessment in 2003 and 959 participants were included for the final analysis. Incident hypertension was determined by blood pressure status at follow-up. In unadjusted model, both square root of HOMA-IR (OR:3.37, 95%CI: 2.10-6.64) and HOMA-B (OR:0.996, 95%CI: 0.992-0.999) were related to incident hypertension. In multivariate model, square root of HOMA-IR (OR:1.97, 95%CI: 1.05-3.70), but not HOMA-B, was associated with incident hypertension. After further adjustment for baseline CAF, the positive relationship between the square root of HOMA-IR and incident hypertension disappeared. In contrast, LF/HF ratio (OR:1.18, 95%CI: 1.01-1.37), HF power (OR:0.98, 95%CI: 0.96-0.999), and E/I ratio (OR:0.71, 95%CI: 0.54-0.95) were each independently associated with incident hypertension after further adjustment for HOMA measures.

CONCLUSION

Sympathovagal imbalance with an apparently decreased parasympathetic tone is an important predictor of incident hypertension independent of IR.

Assessment of the magnitude of contextual and individual demographic effects on diabetes mellitus and glucose intolerance in rural Southwest China: a multilevel analysis

OBJECTIVE

This study aimed to determine the contribution of individual and contextual socioeconomic status (SES) to the prevalence of diabetes mellitus and glucose intolerance in the adult population in rural southwest China.

METHODS

A population-based cross-sectional study of diabetes was performed in 4801(2152 men) Chinese adults (≥ 25 years old). Multilevel logistic regression model was used to examine the association between individuals' and townships' variables and the prevalence of diabetes mellitus and glucose intolerance.

RESULTS

The age-and gender-standardized prevalence of diabetes mellitus and glucose intolerance were 7.1% (3.6% for undiagnosed) and 8.8% in adults aged ≥ 25 years, respectively, and increasing with age. Females were more likely to develop diabetes than males. The probability of developing diabetes increased with BMI. Both contextual and individual educational level and yearly household income were found to be negatively associated with the prevalence of diabetes. Residence in communities with a higher percentage of ethnic minorities was associated with higher prevalence of diabetes. Smoking had a protective effect for diabetes, drinking had a positive association with diabetes mellitus and glucose intolerance.

CONCLUSIONS

Diabetes mellitus and glucose intolerance are common in rural adults of southwest China by international standards. These results indicate that diabetes mellitus has become a major public health problem in rural areas in southwest China, and strategies aimed at the prevention and treatment of diabetes mellitus and glucose intolerance are needed.

Time trend analysis of the prevalence and incidence of diagnosed type 2 diabetes among adults in Taiwan from 2000 to 2007: a population-based study

Background

The prevalence of type 2 diabetes has rapidly increased in the Taiwanese population with the increasing prevalence of a sedentary lifestyle and high-calorie dietary intake. This study aims to determine the annual trends of the prevalence and incidence of diagnosed type 2 diabetes among adults in Taiwan from 2000 to 2007.

Methods

A population-based study of all residents aged 20 years and over (12,191,076 in 2000 and 18,772,180 in 2007) enrolled in the National Health Insurance (NHI) program, the database of which was used to identify patients diagnosed with type 2 diabetes. The annual prevalence and incidence of diagnosed type 2 diabetes were estimated using the International Classification of Diseases, 9^th Revision, Clinical Modification diagnostic codes based on age, gender, insurance premium, and urbanization degree. Logistic regression was used to estimate the odds ratios (OR) of risk factors, as well as to examine the trend in the annual prevalence or incidence of diagnosed type 2 diabetes from 2000 to 2007.

Results

The crude annual prevalence of diagnosed type 2 diabetes increased significantly from 5.79% in 2000 to 8.30% in 2007. The increase was highest in 2007, among men, individuals aged ≥ 80 years, and individuals residing in aging society areas [OR (95% CI): 1.416 (1.412–1.420), 1.033 (1.032–1.034), 31.810 (31.690–31.931), and 1.090 (1.085–1.094), respectively]. The crude incidence fluctuated throughout the study period, ranging from 7.72 per 1,000 in 2006 to 8.98 per 1,000 in 2000. The decrease was highest in 2006, among individuals with an insurance premium ≥ median value [0.933 (0.925–0.942) and 0.810 (0.805–0.815), respectively]. The greatest increase was among men, individuals aged 60 to 79 years, and individuals residing in aging society areas [1.150 (1.145–1.155), 15.452 (15.329–15.576), and 1.127 (1.113–1.142), respectively].

Conclusion

This study demonstrated the substantial increase in annual prevalence of diagnosed type 2 diabetes among adults in Taiwan from 2000 to 2007. The incidence fluctuated between 2000 and 2007.

Incidence and prevalence rates of diabetes mellitus in Taiwan: analysis of the 2000-2009 Nationwide Health Insurance database

BACKGROUND/PURPOSE

Formerly, Taiwan's diabetic population has been estimated by surveys conducted at irregular intervals and using different sampling methods. To obtain nationwide data on the incidence and prevalence of diabetes mellitus (DM) in Taiwan, we performed an analysis of the 2000-2009 claim data from the National Health Insurance (NHI) database.

METHODS

One-third of the claims in the NHI database from 2000 to 2009 were randomly sampled. DM was defined by three or more outpatient visits with diagnostic codes (ICD-9-CM: 250 or A code: A181) within 1 year or by one inpatient discharge diagnosis of DM. Confirmation of type 1 diabetes mellitus was based on the issue of a catastrophic illness certificate with the same diagnostic codes. Age and/or gender distribution for DM were determined.

RESULTS

In accordance with the global trend for DM, with a near constant standardized incidence rate, there was a more than 70% increase in the total diabetic population, or a 35% increase in the standardized prevalence rate, in Taiwan from 2000 to 2009. The incidence of diabetes was higher in men, especially in the 20-59-year-old age group, and the total number of men with diabetes exceeded the number of women with diabetes in 2005. However, the prevalence and incidence rates in women over the age of 60 years were higher than those in men. Type 1 DM was present in less than 1% of the diabetic population in Taiwan.

CONCLUSION

The incidence of diabetes, including type 1, remained stable over this 10-year period in Taiwan. However, the incidence rate in men aged 20-59 years was higher than that in age-matched women. With our nationwide database, subgroup analysis of DM incidence can be performed to refine our health policies for the prevention, screening, and treatment of diabetes mellitus.

Trends in prevalence of diabetes in Asian countries

Diabetes is a major lifestyle disorder, the prevalence of which is increasing globally. Asian countries contribute to more than 60% of the world’s diabetic population as the prevalence of diabetes is increasing in these countries. Socio-economic growth and industrialization are rapidly occurring in many of these countries. The urban-rural divide in prevalence is narrowing as urbanization is spreading widely, adversely affecting the lifestyle of populations. Asians have a strong ethnic and genetic predisposition for diabetes and have lower thresholds for the environmental risk factors. As a result, they develop diabetes at a younger age and at a lower body mass index and waist circumference when compared with the Western population. The adverse effect of physical inactivity and fatty food are manifested as the increasing rate of overweightness and obesity, even among children. The health care budgets for the disease management are meager and the health care outcome is far from the optimum. As a result, complications of diabetes are common and the economic burden is very high, especially among the poor strata of the society. National endeavors are urgently needed for early diagnosis, effective management and for primary prevention of diabetes. This editorial aims to highlight the rising trend in prevalence of diabetes in Asia, its causative factors and the urgent need to implement national strategies for primary prevention of type 2 diabetes.

Waist-to-height ratio, waist circumference, and body mass index as indices of cardiometabolic risk among 36,642 Taiwanese adults

PURPOSE

We aimed to investigate the association of body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) with cardiometabolic risk.

METHODS

In this cross-sectional study, 21,038 men and 15,604 women who participated in a health check-up were included.

RESULTS

In both men and women, the area under the curve (AUC) of WHtR was significantly greater than that of BMI or WC in the prediction of diabetes, hypertension, high total cholesterol, high triglycerides, and low HDL-cholesterol (P < 0.05 for all). The AUC for WHtR in the prediction of metabolic syndrome (MS) was also highest in the women (P < 0.05). After adjustment for potential confounders, the odds ratios and 95% confidence intervals for MS for each standard deviation increase in BMI, WHtR, and WC were 1.47 (1.46-1.49), 1.32 (1.31-1.33), and 1.19 (1.18-1.19), respectively. Finally, patients of either sex with a normal BMI or WC level, but with an elevated WHtR, had higher levels of various cardiometabolic risk factors in comparison with their normal BMI or WC, but low WHtR, counterparts (P < 0.05 for all).

CONCLUSION

Among Taiwanese adults, a WHtR greater than 0.5 is a simple, yet effective indicator of centralized obesity and associated cardiometabolic risk, even among individuals deemed 'healthy' according to BMI and WC.

Multilevel analysis of habitual physical activity and metabolic syndrome in Northern Taiwan

OBJECTIVE

This study examines the relationship between the availability of public facilities for habitual physical activity in the community and metabolic syndrome in northern Taiwan, one of most densely populated countries in the world.

METHODS

Subjects consisted of 14,658 participants (43.3% men and 56.7% women) ≥40 years old (mean=59.5) from 10 districts of Taoyuan County in a health check-up program in 2004-2005. Public facilities for habitual physical activity included school campuses and parks, and the density of such facilities was categorized into four levels. Multilevel logistic regression models were created to examine the effect on metabolic syndrome at both the individual and the contextual level using MLwiN software.

RESULTS

The addition of the contextual variable to the model that included individual characteristics led to a further reduction of 7.2% in the variance. Using the facility density level I as the reference, the odds ratios (95% confidence interval) of metabolic syndrome for levels II, III, and IV were 0.87 (0.71-1.07), 0.87 (0.68-1.12), and 0.78 (0.61-0.99), respectively, with the trend test reaching significance.

CONCLUSION

Greater availability of free facilities for habitual physical activity in a district was associated with a lower risk of metabolic syndrome among its residents.

Body mass index and diabetes in Asia: a cross-sectional pooled analysis of 900,000 individuals in the Asia cohort consortium

BACKGROUND

The occurrence of diabetes has greatly increased in low- and middle-income countries, particularly in Asia, as has the prevalence of overweight and obesity; in European-derived populations, overweight and obesity are established causes of diabetes. The shape of the association of overweight and obesity with diabetes risk and its overall impact have not been adequately studied in Asia.

METHODS AND FINDINGS

A pooled cross-sectional analysis was conducted to evaluate the association between baseline body mass index (BMI, measured as weight in kg divided by the square of height in m) and self-reported diabetes status in over 900,000 individuals recruited in 18 cohorts from Bangladesh, China, India, Japan, Korea, Singapore and Taiwan. Logistic regression models were fitted to calculate cohort-specific odds ratios (OR) of diabetes for categories of increasing BMI, after adjustment for potential confounding factors. OR were pooled across cohorts using a random-effects meta-analysis. The sex- and age-adjusted prevalence of diabetes was 4.3% in the overall population, ranging from 0.5% to 8.2% across participating cohorts. Using the category 22.5-24.9 kg/m²) as reference, the OR for diabetes spanned from 0.58 (95% confidence interval [CI] 0.31, 0.76) for BMI lower than 15.0 kg/m² to 2.23 (95% CI 1.86, 2.67) for BMI higher than 34.9 kg/m². The positive association between BMI and diabetes prevalence was present in all cohorts and in all subgroups of the study population, although the association was stronger in individuals below age 50 at baseline (p-value of interaction<0.001), in cohorts from India and Bangladesh (p<0.001), in individuals with low education (p-value 0.02), and in smokers (p-value 0.03); no differences were observed by gender, urban residence, or alcohol drinking.

CONCLUSIONS

This study estimated the shape and the strength of the association between BMI and prevalence of diabetes in Asian populations and identified patterns of the association by age, country, and other risk factors for diabetes.

The correlates of leisure time physical activity among an adults population from southern Taiwan

BACKGROUND

Assessing the correlates of practicing physical activity during leisure time is important with regard to planning and designing public health strategies to increase beneficial behaviors among adult populations. Although the importance of leisure time physical activity (LTPA) is highlighted in many Western countries, there are not many publications on physical activity patterns, and even less on their correlates, in non-Western societies. The goal of this study was thus to explore the determinants influencing adults' leisure time physical activity (LTPA) in a city in southern Taiwan.

METHODS

A cross-sectional population-based study was conducted in 2007, using a standardized questionnaire. Energy expenditure was dichotomized into two groups based on the recommended levels of moderate physical activity from LTPA: ≥10 or < 10 MET·hr·wk(-1). Logistic regression analyses were applied to the results.

RESULTS

A total of 762 subjects with valid data took part in the study (mean age 53.8 ± 13.8 years). In multivariate logistic regression analysis, we found the following results: Age was positively associated with LTPA. Adults with stronger perceived convenience of exercise facilities (OR = 2.04; 95%CI = 1.28-3.24) and past exercise experience in school (OR = 1.86; 95%CI= 1.19-2.91) participated in more LTPA. Subjects with more general social support (OR = 1.66;95%CI = 1.13-2.44), greater knowledge about the health benefits of exercise (OR = 1.85;95%CI = 1.25-2.74), more sports media consumption (OR = 1.94;95%CI = 1.26-2.98), and higher self-efficacy (OR = 3.99;95%CI = 2.67-5.97) were more likely to engage in LTPA. Further analysis comparing different sources of social support showed only social support from friends had a significant positive association (OR = 1.73;95%CI = 1.14-2.63) with increased LTPA.

CONCLUSIONS

LTPA in southern city of Taiwan showed some unique associations with age, socioeconomic status and media consumption that are not commonly reported in the Western World and similar associations with regards to psychosocial correlates of LTPA participation. Further studies from developing countries are warranted to highlight culture-specific differences in physical activity participation.

Prevalence of diabetes in patients with bipolar disorder in Taiwan: a population-based national health insurance study

OBJECTIVE

We investigated the prevalence and correlates of diabetes in patients with bipolar disorder in Taiwan.

METHODS

The National Health Research Institute provided a database of 1,000,000 random subjects from which we selected a sample of 766,427 subjects aged 18 years and over. We identified study subjects who had at least one service claim during 2005, with a primary diagnosis of bipolar disorder or with a prescription for treatment of diabetes.

RESULTS

The prevalence of diabetes in patients with bipolar disorder was higher than in the general population (10.77% vs. 5.57%, OR, 2.01; 99% CI, 1.64-2.48). Compared with the general population, patients with bipolar disorder had a higher prevalence of diabetes in all age groups under 60 years; among females and males; among lower insurance amount groups; among those living in the northern, central and southern regions and among residents living in urban and rural areas. Antipsychotic use was associated with a higher prevalence of diabetes in persons with bipolar disorder.

CONCLUSIONS

Patients with bipolar disorder had a higher prevalence of diabetes than the general population. Prevention, early detection and treatment of diabetes are important issues for patients with bipolar disorder.

Altered cardiac autonomic function may precede insulin resistance in metabolic syndrome

BACKGROUND

Previous studies on the change of cardiac autonomic function and insulin resistance in metabolic syndrome recruited subjects with cardiovascular-related disease and defined metabolic abnormality with a more severe cutoff. We explored the alteration of cardiac autonomic function and insulin resistance in predisease community dwellers with different numbers of metabolic abnormalities.

METHODS

A total of 1298 subjects were classified as none (n=539), one (n=378), 2 (n=218), and 3 or more metabolic abnormalities (n=154). Insulin resistance was calculated by homeostatic model assessment. Cardiac autonomic function included 5-minute standard deviation of R-R interval, low- and high-frequency power spectrum, and low-/high-frequency power spectrum ratio, the ratio of the longest R-R interval around the 30th beat and the shortest R-R interval around the 15th beat after standing, and the ratio of the longest expiratory R-R interval to the shortest inspiratory R-R interval during deep breathing.

RESULTS

Subjects with a single metabolic abnormality or more had a lower standard deviation of R-R interval and expiratory/inspiratory ratio than subjects without metabolic abnormality in multivariate analysis. Subjects with 3 or more metabolic abnormalities had a higher low-/high-frequency power spectrum ratio, but a lower high-frequency power. Insulin resistance was higher in groups with 2 metabolic abnormalities or more, but not in the group with one metabolic abnormality, than those without metabolic abnormality.

CONCLUSIONS

Cardiac autonomic function altered in predisease subjects with one or more metabolic abnormalities, while insulin resistance existed in subjects with 2 or more metabolic abnormalities. Thus, autonomic function change may precede insulin resistance in the initiation of metabolic syndrome.

Diabetes, pre-diabetes and associated risks on Minnesota code-indicated major electrocardiogram abnormality among Chinese: a cross-sectional diabetic study in Fujian province, southeast China

The goal of this study was to determine the prevalence of diabetes mellitus (DM), impaired glucose regulation (IGR) and related metabolic disorders (overweight, obesity and hypertension) in a Chinese population (20-74 years old). An additional goal was to investigate the relationship between glucose metabolism and the Minnesota code-indicated major abnormal electrocardiogram (MA-ECG). There were 3960 individuals selected from urban and rural areas of Fujian, China from July 2007 to May 2008 by multistage-stratified sampling. Ultimately, data from 3208 subjects (20-74 years old) were analysed (including physical measurements, blood biochemical analysis, oral glucose tolerance test and 12-lead resting ECG). According to World Health Organization diagnostic criteria, the prevalence rates of DM and IGR were 9.51% (male, 10.08%; female, 9.14%) and 14.40% (male, 14.48%; female, 14.35%) respectively. Newly diagnosed DM was found in 53.44% of the diabetic subjects. Based on the 2000 China census, the age-standardized prevalence rates of DM and IGR were 7.19% (male, 7.74%; female, 6.61%) and 11.96 % (male, 12.35%; female, 11.56%) respectively. The age-standardized prevalence rates of DM and IGR in urban areas (7.74% and 12.97% respectively) were slightly but no significantly higher than in rural areas (6.67%, 10.86%). The prevalence rates of overweight, obesity and hypertension were 25.50%, 3.52% and 28.52% respectively (age- and sex- standardized rates: 23.69%, 3.02 % and 22.45 %). After adjusting for other confounding risk factors, multiple logistic regression analysis showed that DM and impaired glucose tolerance were independent risk factors for MA-ECG. Non-diabetic subjects with increased 30-min plasma glucose (PG) after an oral glucose load had a higher risk of MA-ECG after adjusting for other risk factors, especially in those with normal glucose tolerance but with 30-min PG >or= 7.8 mmol L(-1) (odds ratio = 1.371 [1.055-1.780]). The prevalence rates of DM and IGR as well as other metabolic disorders have increased dramatically in the last decade in China, especially in rural areas, with many undiagnosed cases of DM. Even slightly elevated PG levels may predict early cardiovascular events.

Prevalence of diabetes in patients with schizophrenia in Taiwan: a population-based National Health Insurance study

OBJECTIVE

We conducted this study to investigate the prevalence and correlates of diabetes in patients with schizophrenia in Taiwan.

METHODS

The National Health Research Institute provided a database of 1,000,000 random subjects for study. We obtained a random sample aged 18 years and over of 766,427 subjects in 2005. Those study subjects who had at least one service claim during this year for either ambulatory or inpatient care, with a primary diagnosis of schizophrenia or with a prescription for treatment of diabetes, were identified.

RESULTS

The prevalence of diabetes in patients with schizophrenia was higher than in the general population (7.90% vs. 5.57%, odds ratio [OR], 1.81; 95% confidence interval [CI], 1.61-2.03). Compared with the general population, patients with schizophrenia revealed a higher prevalence of diabetes in all age groups, except age 70 or more years; among females (10.30% vs. 5.42%, p<0.001), and males (5.93% vs. 5.73%, p<0.001); among all insurance amount groups; among those living in the northern (7.56% vs. 4.89%, p<0.001), central (8.26% vs. 5.61%, p<0.001), southern regions (8.45% vs. 6.62%, p<0.001); and among residents living in urban (8.18% vs. 5.19%, p<0.001) and rural areas (7.99% vs. 6.15%, p<0.001).

CONCLUSIONS

Patients with schizophrenia had a much higher prevalence of diabetes in younger adult age groups and in females than in the general population, a finding that deserves further biological and psychosocial study in the future.

Population-based study on the prevalence and risk factors of orthostatic hypotension in subjects with pre-diabetes and diabetes

OBJECTIVE

The aim of this study was to investigate the relationship between pre-diabetes and orthostatic hypotension and to examine the prevalence and correlates of orthostatic hypotension in community dwellers with normal glucose tolerance (NGT), pre-diabetes, and diabetes.

RESEARCH DESIGN AND METHODS

All participants were classified as having NGT (n = 1,069), pre-diabetes (n = 412), or diabetes (n = 157). Orthostatic hypotension was defined as a decline in systolic/diastolic blood pressure of > or =20/10 mmHg when an individual changed from a supine to a standing position. The cardiovagal response to standing was the ratio between the longest RR interval around beat 30 and the shortest RR interval around beat 15 after standing (30 max-to-15 min ratio).

RESULTS

The prevalences of orthostatic hypotension were 13.8, 17.7, and 25.5% in subjects with NGT, pre-diabetes, and diabetes, respectively. For all subjects, age, diabetes, hypertension, and a decreased 30 max-to-15 min ratio, but not pre-diabetes, were independently associated with orthostatic hypotension. Age, hypertension, and 30 max-to-15 min ratio were the correlates of orthostatic hypotension in NGT subjects. Age and hypertension were related to orthostatic hypotension in pre-diabetic subjects. A1C and hypertension were the determinants of orthostatic hypotension in diabetic subjects. Supine blood pressure was related to orthostatic hypotension in all subjects and subgroups.

CONCLUSIONS

Pre-diabetic subjects do not have a higher risk of orthostatic hypotension than subjects with NGT, although the risk of orthostatic hypotension is higher in diabetic subjects. Hypertension and supine blood pressure were risk factors for orthostatic hypotension in both pre-diabetic and diabetic subjects. Age and A1C were the correlates of orthostatic hypotension in pre-diabetic and diabetic subjects, respectively. The cardiovagal response to standing is an important determinant of orthostatic hypotension in subjects with NGT but not in pre-diabetic and diabetic subjects.

Population-based study on the prevalence and correlates of orthostatic hypotension/hypertension and orthostatic dizziness

There are no epidemiological studies of orthostatic hypotension (OH)/hypertension (OHT) and orthostatic dizziness (OD) in adults across all age groups. The aim of this study is to examine the prevalence and correlates of OH, OHT, and OD in community dwellers aged > or = 20 years. OH was defined as a decline in systolic/ diastolic blood pressure of > or = 20/10 mmHg when a person stood up from a supine position. OHT was a postural increase of > or = 20 mmHg in systolic blood pressure. OD was dizziness, lightheadedness, or faintness as the person stood up. A total of 1,638 adults were included. Subjects were classified as normotensive, pre-hypertensive, or hypertensive. The prevalences of OH, OHT, and OD were 15.9, 1.1, and 4.8%, respectively. OD was associated with neither OH nor OHT. None of the subjects aged < 40 had OHT; hypertension (p = 0.030) and female gender (p < 0.001) were the independent correlates of OH and OD, respectively, in that age range. For subjects aged > or = 40 years, age (p = 0.003), pre-hypertension (p = 0.024), hypertension (p = 0.008), and diabetes mellitus (p = 0.036) were independently related to OH. Age (p < 0.001) and supine systolic blood pressure (p = 0.023) were the correlates of OHT. Female gender (p < 0.001) and sedatives/hypnotics (p = 0.040) were associated with OD. In conclusion, age, pre-hypertension, hypertension, and diabetes mellitus were important determinants of OH. OD was more prevalent in women and in subjects using sedatives/hypnotics. The risk of OHT increased with age and with supine systolic blood pressure in adults aged > or = 40 years. OH and OHT cannot be determined solely from the presence of OD because of their dissociation.

Epidemiological evidence of altered cardiac autonomic function in overweight but not underweight subjects

BACKGROUND

Little is known about the altered cardiac autonomic function (CAF) across different levels of body mass index (BMI), including underweight, normal weight, overweight and obesity. This study provides a thorough analysis to clarify the CAF change in subjects with underweight, overweight and obesity.

METHODS

According to the World Health Organization (WHO) Asia-Pacific BMI cutoffs, a total of 1437 participants were classified as underweight (n=74), normal weight (n=588), overweight (n=313), obesity I (n=390) and obesity II (n=72). CAF was determined by standard deviation of normal-to-normal (SDNN) intervals or RR intervals, power spectrum in low (LF) and high frequency (HF) (LF, 0.04-0.15 Hz; HF, 0.15-0.40 Hz), and LF/HF ratio at supine for 5 min, the ratio between the 30th and the 15th RR interval after standing from the supine position (30/15 ratio) and the average heart-rate change while taking six deep breaths in 1 min (HR(DB)).

RESULTS

There were significant differences in age, gender, socioeconomic status, blood pressure, HOMA insulin resistance index, fasting glucose, cholesterol, triglyceride and high-density lipoprotein (HDL)-C, and the prevalence of hypertension, ischemic/left bundle branch block (LBBB) electrocardiography (EKG) pattern, current smoking and alcohol use among subjects with underweight, normal weight, overweight, obesity I and II. Univariate analysis showed that SDNN, HR(DB), HF power and the square root of the LF/HF ratio differed among these five groups. Multivariate analysis showed that obesity I and II were inverse correlates of HR(DB) and HF power. Overweight, obesity I and II were positively associated with the square root of the LF/HF ratio. No BMI status was related to SDNN, 30/15 ratio or LF power. Underweight was not the independent correlate of any CAF indices.

CONCLUSIONS

The risk for altered CAF is significant in overweight and obese subjects, independent of cardiovascular risk factors. Underweight is not apparently associated with CAF change.

The combination of fasting plasma glucose and glycosylated hemoglobin predicts type 2 diabetes in Japanese workers

OBJECTIVES

We examined the usefulness of the combined use of fasting plasma glucose (FPG) and hemoglobin Alc (HbA1c) levels to predict the progression of diabetes in a Japanese population.

METHODS

A retrospective cohort study was conducted from 1995 to 2002 among 449 non-diabetic Japanese workers, ages 23-65, in whom baseline FPG levels and HbA1c were measured. Subjects were classified into six groups according to their baseline FPG level: low normal fasting glucose (NFG) (<5.55 mmol/l); high NFG (5.55-6.09 mmol/l); or impaired fasting glucose (IFG) (6.10-6.99 mmol/l), in combination with baseline HbA1c level: low HbA1c (<5.8%) and high HbA1c (> or =5.8%). The cumulative incidence of diabetes in 2002, as defined by the 1997 American Diabetes Association (ADA) diagnostic criteria, was compared between groups.

RESULTS

The overall cumulative incidence of diabetes was 3.8% (17/449). The cumulative incidence of diabetes was 0.6% (2/339) in those with low NFG/normal HbA1c; 0% (0/24) with low NFG/high HbA1c; 6.4% (3/47) with high NFG/normal HbA1c; 23.1% (3/13) with high NFG/high HbA1c; 17.6% (3/17) with IFG/normal HbA1c; and 66.7% (9/17) with IFG/high HbA1c. The odds ratios for diabetes, adjusted for age, sex, body mass index (BMI) and family history of diabetes, were 5.3 (95% CI, 3.0-9.3) and 3.0 (1.7-5.3), per 0.56 mmol/l increase in FPG and 0.5% increase in HbA1c, respectively.

CONCLUSIONS

The combined use of FPG and HbA1c levels predicts the progression to diabetes in individuals with no apparent risk. In particular, the combination is recommended for individuals with a FPG > or =5.55 mmol/l.

No allele variation of the MAOA gene promoter in male Chinese subjects with attention deficit hyperactivity disorder

The aim of the current study was to examine any difference in the repeat sequence of the monoamine oxidase A (MAOA) gene promoter between males with attention deficit hyperactivity disorder (ADHD) and randomly selected subjects in a community. The role of the MAOA gene promoter in ADHD cases was also investigated. The total of 244 participants included 57 male ADHD subjects as the case group and 187 males, also in southern Taiwan, as the community controls. There was no significantly different distribution in the repeat sequence of the MAOA gene promoter (chi2 = 3.895, d.f. = 3, p = 0.273), and no significantly different distribution of 'long-form' and 'short-form' alleles between the ADHD group and the male community group was noted (chi2 = 2.484, d.f. = 1, p = 0.115). Some aspects of clinical response are mentioned in the discussion of this study which are worth exploring further in the future.

In addition to obesity and insulin resistance, microalbuminuria and diminished insulin secretion are linked with the metabolic syndrome in community-dwelling nondiabetic Taiwanese subjects

Although insulin resistance and obesity are currently considered primary factors underlying development of the metabolic syndrome, microalbuminuria and inadequate insulin secretion may also be involved. The present study is the first to examine intercorrelations among these factors in a community-based Taiwanese population. An epidemiological survey of chronic diseases conducted in 1996 was utilized to evaluate 1340 community-dwelling, nondiabetic adults. Principal component factor analyses involving varimax orthogonal rotation of transformed continuously distributed variables were performed. Sex-specific factor analyses yielded four separate factors in women (obesity/insulin resistance, lipid, blood pressure and insulin resistance/secretion factors) and three in men (obesity/insulin resistance/secretion, lipid and blood pressure factors). For men the corrected insulin response clustered with obesity, and insulin resistance loaded on the same factor, explaining 31% of variance; however, microalbuminuria was closely linked with blood pressure variables, and the corrected insulin response loaded on the same factor, explaining 13.2% of variance. Obesity and insulin resistance were confirmed as central anomalies of all features of the metabolic syndrome. The observed linkage of impaired beta-cell function and microalbuminuria with the metabolic syndrome should facilitate prediction of the onset of cardio-vasculo-metabolic disorders. Inadequate beta-cell function and microalbuminuria are plausible components of the metabolic syndrome in Taiwanese subjects.

Epidemiological characteristics of diabetes mellitus and impaired glucose regulation in a Chinese adult population: the Shanghai Diabetes Studies, a cross-sectional 3-year follow-up study in Shanghai urban communities

AIMS/HYPOTHESIS

To estimate the prevalence and incidence of diabetes mellitus and impaired glucose regulation (IGR) in a Chinese population aged 20-94 years.

SUBJECTS AND METHODS

A group of 5,628 randomly selected adults, aged 20-94 years, living in the Huayang and Caoyang communities in Shanghai, China, were investigated between 1998 and 2001. During 2002-04, 2,666 subjects were followed up. All the participants underwent anthropometric measurements, blood biochemical analyses and a 75-g OGTT.

RESULTS

Based on the 2000 census data of China, the age-standardised prevalences were 6.87% for diabetes and 8.53% for IGR at baseline. More than two in five cases with diabetes were undiagnosed. The age-adjusted prevalence of diabetes and IGR increased with age. The age-adjusted prevalences of hypertension, dyslipidaemia and overweight in males were significantly higher (p < 0.001) than in females. The 3-year cumulative incidence rates of diabetes and IGR were 4.96 and 11.10%, respectively. The relative risk of developing diabetes was significantly higher in subjects with IGR than in subjects with NGT (p < 0.001).

CONCLUSIONS/INTERPRETATION

The prevalence and incidence rates for diabetes or IGR have increased dramatically over the last decades, especially in younger age groups. A large proportion of cases are undiagnosed. We strongly recommend that population-based diabetes screening programmes should be implemented and generalised for younger people.

Fasting cut-points in determining prevalence of diabetes in an Arab population of the Middle East

We used two cross-sectional surveys involving 6356 Omanis aged >or= 20 years to estimate the effect of the 1997 American Diabetes Association (ADA) criteria on the prevalence of diabetes mellitus in Oman and develop a validated optimal fasting plasma glucose (FPG) cut-point which best predicts diabetes diagnosed 2-h post oral glucose tolerance test. Applying the 1997 ADA criteria to Oman would underestimate diabetes by 18%. The sensitivity of the ADA criteria was 68.3% (95% CI 64.0-72.4%) and specificity was 98.6% (95% CI 98.2-98.9%). Receiver-operating characteristic (ROC) curve depicted FPG>5.9 mmol/l to best predict 2-h post-load glucose >or=11.1 mmol/l. The area under the ROC curve was 0.95 (95% CI 0.94-0.95%) with no significant difference between obese and non-obese individuals. This cut-point had a sensitivity of 87.5% (95% CI 84.3-90.3%), specificity of 90.8% (95% CI 89.9-91.7%) and likelihood ratio of 9.5. On validation in an independent population, the sensitivity and specificity of the depicted cut-point remained high 84.2% (95% CI 77.0-89.8%) and 80.2% (95% CI 78.0-82.4%) compared to the ADA values 60.4% and 96.6%, respectively. Our study identified a lower cut-point to diagnose diabetes than that suggested by the 1997 ADA criteria.

Epidemic obesity and type 2 diabetes in Asia

The proportions of people with type 2 diabetes and obesity have increased throughout Asia, and the rate of increase shows no sign of slowing. People in Asia tend to develop diabetes with a lesser degree of obesity at younger ages, suffer longer with complications of diabetes, and die sooner than people in other regions. Childhood obesity has increased substantially and the prevalence of type 2 diabetes has now reached epidemic levels in Asia. The health consequences of this epidemic threaten to overwhelm health-care systems in the region. Urgent action is needed, and advocacy for lifestyle changes is the first step. Countries should review and implement interventions, and take a comprehensive and integrated public-health approach. At the level of primary prevention, such programmes can be linked to other non-communicable disease prevention programmes that target lifestyle-related issues. The cost of inaction is clear and unacceptable.

Prevalence of type 2 diabetes mellitus of Chinese populations in Mainland China, Hong Kong, and Taiwan

This article reviews and describes trends and differences in prevalence of type 2 diabetes mellitus of Chinese populations in Mainland China, Hong Kong and Taiwan based on literatures published in the MEDLINE Advanced database (January 1966-October 2005) in both Chinese and English languages. Chinese populations in Hong Kong and Taiwan have significant higher prevalence rates of diabetes than their Mainland counterparts, with odds ratios 1.5 (95% confidence intervals: 1.4, 1.7) and 2.0 (95% confidence intervals: 1.8, 2.2), respectively in 1995-2003 adjusted for age and diagnostic criteria. Using stratified diagnostic criteria; the odds ratios in Hong Kong and Taiwan were consistently higher than Mainland China for the periods of 1985-1994 and 1995-2003. A large proportion, i.e. 68.6% (95% confidence intervals: 67.4%, 69.7%) of diabetic patients remains undiagnosed in Mainland China as compared to 52.6% (95% confidence intervals: 49.8%, 55.5%) undiagnosed in Hong Kong and Taiwan. The prevalence rates of diabetes and impaired glucose tolerance of the Chinese populations rise in older age groups. In tandem with economic development and change toward lifestyle that is lack of physical activity and rich in high-fat diet, prevalence of diabetes of the Chinese populations are on the rise. If the undiagnosed individuals left uncontrolled, they are subject to higher risks of developing diabetes and its complications. These will increase the burdens of diabetes medically and financially.

Dopamine D4 receptor gene and the −521C>T polymorphism of the upstream region of the dopamine D4 receptor gene in schizophrenia

OBJECTIVE

The dopamine D4 receptor (DRD4) is a candidate gene for increasing genetic susceptibility to schizophrenia. A recent study found that a -521C>T promoter base pair change affects transcriptional regulation of the DRD4 gene. The present study was designed to investigate the role of both the -521C>T single nucleotide polymorphism and the DRD4 variable number tandem repeat (VNTR) polymorphism.

METHODS

A case-control study of 630 Chinese schizophrenic patients and 428 Chinese controls was conducted to test for allelic association with schizophrenia.

RESULTS

The number of DRD4 VNTR fragments was associated with schizophrenia. Long DRD4 VNTR fragments as opposed to short fragments were commoner in schizophrenia. No evidence was found for allelic association between the -521C>T DRD4 polymorphism and schizophrenia.

CONCLUSIONS

This study provides preliminary and unconfirmed evidence for the involvement of the DRD4 repeat VNTR in the pathogenesis of schizophrenia.

Protective effect of the apo epsilon2 allele in major depressive disorder in Taiwanese

OBJECTIVE

Major depression is an important comorbidity in Alzheimer's disease, which is definitely associated with the apolipoprotein E (apo E) polymorphism. The aim of this study was to explore the role of the different apo E polymorphisms in major depressive disorder (MDD) in a Taiwanese population.

METHOD

We examined apo E genotypes in 273 Taiwanese patients with MDD and 429 healthy community controls, and compared their polymorphism distribution.

RESULTS

The allelic frequency of apo epsilon2 was significantly lower in patients with MDD than in the controls, whereas no significant difference in apo epsilon4 allelic frequency between these two groups was found.

CONCLUSION

The apo epsilon4 allele was not associated with MDD in this study. However, the finding of a lower frequency of the apo epsilon2 allele in MDD could lead to the conclusion that the apo epsilon2 allele likely provides a protective effect against MDD in the Taiwanese population.

Does Arsenic Exposure Increase the Risk for Diabetes Mellitus?

OBJECTIVE

Long-term arsenic exposure has been reported to associated with prevalence, incidence, and mortality of diabetes mellitus (DM). A tap water supply system was implemented in the early 1960s in the blackfoot disease (BFD) endemic areas. The objective of this study is to examine whether DM mortality decreased after the improvement of drinking water supply system through elimination of arsenic exposure from artesian well water.

METHODS

Standardized mortality ratios (SMRs) for DM were calculated for the BFD endemic area for the years 1971-2000.

RESULTS

The study results show that mortality from DM declined in females (but not in males) gradually after the improvement of drinking water supply system.

CONCLUSIONS

Based on the reversibility criterion, the association between arsenic exposure and DM is likely to be casual for females but not in males.

Secular trends in coronary heart disease mortality, hospitalization rates, and major cardiovascular risk factors in Taiwan, 1971-2001

BACKGROUND

While mortality from coronary heart disease (CHD) has declined substantially in most developed countries in recent decades, discordant rising trends have been observed in many developing and newly developed countries. In this study, we examined the trends of CHD mortality and its hospitalization rate, and correlated the trends with changes in major cardiovascular risk factors in Taiwan.

METHODS

Mortality data during the period 1971-2001 were obtained from official vital statistics. Hospitalization rates were calculated using information extracted from the National Health Insurance Database, which was available from 1996 to 2001. Changes in major cardiovascular risk factors were obtained from official statistics and review of previous epidemiologic studies.

RESULTS

In 2001, the age-standardized CHD mortality in Taiwan was 28.7 per 100,000 for men and 15.5 per 100,000 for women. For both men and women, age-adjusted CHD mortality increased slowly but steadily from 1971 to 1992, but after that, a downward trend was observed. Hospitalization rates for CHD, however, increased substantially from 1996 to 2001. Levels of per-capita cigarette consumption, dietary fat intake, body mass index, and prevalence of hypertension and diabetes had all increased over the past three decades.

CONCLUSIONS

The overall cardiovascular risk profile has worsened in the general population in Taiwan. The decline in CHD mortality observed in recent years was most likely attributable to the improvement in acute cardiac care and medical treatment among patients with CHD. We anticipated that CHD incidence and prevalence would continue to rise in Taiwan.

Diabetes mellitus in patients with schizophrenia in Taiwan

A higher prevalence of diabetes mellitus (DM) has been reported in schizophrenic patients for decades. But the risk factors for diabetes in these patients were not well understood. The aim of our study is to establish the prevalence of DM in patients with schizophrenia in Taiwan and discover the risk factors associated with it. In 246 recruited schizophrenic patients, the prevalence of DM was 9.8%, not significantly different from that of the general population in Taiwan. However, we found a significantly higher prevalence of DM in younger schizophrenic patients (p=0.001) than in the general population, but not in older patients (p>0.10). Our results showed old age, a longer duration of illness, obesity, and having a family history of DM were independent factors associated with DM in schizophrenia. These results suggest that schizophrenia may make young people more vulnerable to developing DM. Further large-scale, controlled studies should be done to confirm our results.

Correlation between striatal dopamine D2 receptor density and neuroticism in community volunteers

The central dopaminergic system, as well as the central serotonergic system, has been reported to be correlated with higher neuroticism. The present study examined the relationship between striatal dopamine D(2) receptor density and neuroticism. Neuroticism was assessed with the Maudsley Personality Inventory, and psychiatric morbidity was evaluated with both the Mini International Neuropsychiatric Interview and the Hamilton Depression Rating Scale (HAM-D). Single photon emission computed tomography with [(123)I]iodo-benzamide was used to measure striatal dopamine D(2) receptor density. HAM-D scores and psychiatric morbidity in high-neuroticism individuals were higher than in low-neuroticism individuals. Moreover, striatal dopamine D(2) receptor densities were significantly correlated with the neuroticism score of the 41 subjects. The central dopaminergic system may play an important role in the neurobiological characteristics of neuroticism.

Norms of performance of sustained attention among a community sample: Continuous Performance Test study

The Continuous Performance Test (CPT) is a widely used measure of sustained attention, which is a preferred tool for assessing various mental functions. A well-established norm for CPT is essential when choosing a suitable threshold for classifying individuals as either case (CPT impairment) or non-case. The CPT performance of 900 adults who were randomly chosen from a community survey was measured to establish the norms for subgroups with different gender, age, and educational levels. The results revealed that age and educational level are significantly associated with the performance sensitivity (d') of CPT. Male subjects perform better than female subjects. Seventeen percent of the subjects scored higher on the masked CPT than on the unmasked CPT. Subjects who could not finish the masked CPT had the characteristics of older age and fewer years of education. When classifying a patient as case or non-case, his/her CPT performance should be considered relative to the norms for his/her gender, age, and educational levels.

Prevalence and risk factors for diabetes in Ho Chi Minh City, Vietnam

AIMS

To determine the prevalence of diabetes and associated risk factors in Ho Chi Minh City, Vietnam.

METHODS

A total of 2932 participants aged 15 and above in Ho Chi Minh City were screened for diabetes in a cross-sectional study. The study was conducted from March-May 2001. Demographic, occupation, anthropometry and blood pressure were recorded. Blood glucose was calculated on fasting capillary and venous blood. The classification of diabetes and impaired fasting glucose (IFG) was carried out according to WHO and American Diabetes Association criteria.

RESULTS

The crude prevalence of diabetes and IFG were 6.6 and 3.2%, respectively. After age, sex-adjustment to the Vietnam population census, the prevalence was 3.8 and 2.5%, respectively; approximately 40% of cases were found to be newly diagnosed diabetes. The crude prevalence of diabetes in the urban area was approximately 2.8 times higher than that recorded in the 1993 study (6.9 vs. 2.5%, respectively). In this study, there was a positive association between diabetes and sex, age, overweight, waist hip ratio (WHR), and having a history of delivering large for gestational age child; there was a negative association between diabetes and physical activity and occupation.

CONCLUSIONS

This study found that the age, sex-adjusted prevalence of diabetes and IFG in Ho Chi Minh City were 3.8 and 2.5%, respectively, a rapid increase in the recent decade. Our study also indicates that ageing, a high WHR level, overweight and a sedentary lifestyle may be important determinants of the increased prevalence of diabetes during this transition period in Vietnam.

Body mass index and obesity-related metabolic disorders in Taiwanese and US whites and blacks: implications for definitions of overweight and obesity for Asians

BACKGROUND

Recommendations based on scanty data have been made to lower the body mass index (BMI; in kg/m(2)) cutoff for obesity in Asians.

OBJECTIVE

The goal was to compare relations between BMI and metabolic comorbidity among Asians and US whites and blacks.

METHODS

We compared the prevalence rate, sensitivity, specificity, predictive values, and impact fraction of comorbidities at each BMI level and the BMI-comorbidity relations across ethnic groups by using data from the third National Health and Nutrition Examination Survey and the Nutrition and Health Survey in Taiwan (1993-1996).

RESULTS

For most BMI values, the prevalences of hypertension, diabetes, and hyperuricemia were higher for Taiwanese than for US whites. In addition, increments of BMI corresponded to higher odds ratios in Taiwanese than in US whites for hypertriglyceridemia (P = 0.01) and hypertension (P = 0.075). BMI-comorbidity relations were stronger in Taiwanese than in US blacks for all comorbidities studied. BMIs of 22.5, 26, and 27.5 were the cutoffs with the highest sum of positive and negative predictive value for Taiwanese, US white, and US black men, respectively. The same order was observed for women. For BMIs >27, >85% of Taiwanese, 66% of whites, and 55% of blacks had at least one of the studied comorbidities. However, a cutoff close to the median of the studied population was often found by maximizing sensitivity and specificity. Reducing BMI from >25 to <25 in persons in the United States could eliminate 13% of the obesity comorbidity studied. The corresponding cutoff in Taiwan is slightly <24.

CONCLUSION

These data suggest a possible need to set lower BMI cutoffs for Asians, but where to draw the line is a complex issue.