Fetal Growth, Obesity, and Atopic Disorders in Adolescence: a Retrospective Birth Cohort Study.

BACKGROUND: Developmental status at birth and subsequent obesity have been implicated in the development of childhood atopic dermatitis (AD) and allergic rhinitis (AR). METHODS: The current study analysed the cohort data of 74 688 junior high school students from a national retrospective birth cohort study in Taiwan. A random 10% sample was selected from singleton livebirths with complete data on the analytical variables of interest. Atopic disorders, including AD and AR, were assessed by questionnaires (International Study of Asthma and Allergies in Childhood). Logistic regression analyses were applied with adjustments for related risk factors. RESULTS: Among subjects mainly 13-15 years of age, the estimated prevalence was 7.6% for AD and 22.4% for AR. While the role of fetal growth in allergic disorders was less evident, the risk of developing AD and AR were both influenced by a combination of fetal growth status and adolescent body mass index (BMI). Compared with those with normal fetal growth and school-aged BMI, the risk of developing AD increased 64% among adolescents with both restricted fetal growth and high BMI (odds ratio 1.64, 95% confidence interval 1.37, 1.97). The risk for this combination was higher than that for either restricted fetal growth or high BMI alone. Nevertheless, the overall interaction between BMI and fetal growth status on atopic disorders did not reach statistical significance. CONCLUSIONS: Excessive weight gain could be an important risk factor related to developing atopic dermatitis and allergic rhinitis during adolescence, especially among infants born small for gestational age.

Low birth weight and environmental tobacco smoke increases the risk of wheezing in adolescents: a retrospective cohort study.

BACKGROUND: Low birth weight (LBW) and environmental tobacco smoke (ETS) exposure are each associated with wheezing in children. This study was designed to examine the combined association of LBW and ETS with wheezing. METHODS: A retrospective birth cohort analysis linked with a national survey of allergic disorders among 1,018,031 junior high school students in Taiwan (1995-1996) was analyzed. The reported incidence of wheezing (yes or no) and ETS exposure (4 categories: 0, 1-20, 21-40 and greater than or equal to 41 household cigarettes per day) were obtained from validated questionnaires. Multiple logistic regression models were used to assess the associations of interest. RESULTS: There were 844,003 (83%) subjects analyzed after the exclusion criteria. LBW was associated with an increased risk of reporting ever wheezing (odds ratio [OR] = 1.08, 95% confidence interval [CI] = 1.01-1.16), current wheezing (OR = 1.09, 95% CI = 1.00-1.20) and wheezing with exercise (OR = 1.11, 95% CI = 1.02-1.21) within the smoke-free cohort. Higher ETS exposure correlated to a higher risk of wheezing (ever, current and with exercise). With ETS exposure, adolescents from the lowest birth weight cohorts were more likely to report wheezing (ever, current and with exercise). CONCLUSIONS: ETS and LBW each has been related to increasing public health risk for respiratory symptoms among adolescents. Furthermore, LBW may aggravate the risk among those exposed to ETS. LBW, ETS and associated respiratory impairments may deserve special attention as part of a comprehensive environmental health risk assessment directed toward prevention and intervention.

Body mass index may modify asthma prevalence among low-birth-weight children.

Childhood asthma, a growing health concern, has been associated with low birth weight and elevated body mass index. This study tested the hypothesis that overweight and obese adolescents with a history of low birth weight are at even greater risk of developing asthma. A cohort of 75,871 junior high school students was screened for asthma during 1995-1996 in Taiwan. Birth weight and estimated gestational age were obtained from the birth registry. Logistic regression and simple regression analyses were adjusted for confounding variables. Asthma was more prevalent in those with birth weights below 3,000 g and higher adolescent body mass indexes. Furthermore, those with both characteristics were consistently most likely to have asthma. Whether the asthma diagnosis among low-birth-weight subjects was assigned by physicians or medical questionnaire, the risks were elevated for both overweight (physician diagnosis: odds ratio = 1.41; medical questionnaire: odds ratio = 1.25) and obese (physician diagnosis: odds ratio = 1.38; medical questionnaire: odds ratio = 1.47) boys as well as overweight (physician diagnosis: odds ratio = 1.63; medical questionnaire: odds ratio = 1.30) and obese (physician diagnosis: odds ratio = 1.44; medical questionnaire: odds ratio = 1.32) girls (P < 0.05). Low birth weight predisposes one to develop asthma, and excess body mass amplifies the risk. A sex difference was observed. This study suggests that prenatal care and nutritional counseling could reduce asthma prevalence.

The short-term effects of air pollution on adolescent lung function in Taiwan.

A mass screening of lung function associated with air pollutants for children is limited. This study assessed the association between air pollutants exposure and the lung function of junior high school students in a mass screening program in Taipei city, Taiwan. Among 10,396 students with completed asthma screening questionnaires and anthropometric measures, 2919 students aged 12-16 received the spirometry test. Forced vital capacity (FVC) and forced expiratory flow in 1s (FEV(1)) in association with daily ambient concentrations of particulate matter with diameter of 10 µm or less (PM(10)), sulfur dioxide (SO(2)), carbon monoxide (CO), nitrogen dioxide (NO(2)), and ozone (O(3)) were assessed by regression models controlling for the age, gender, height, weight, student living districts, rainfall and temperature. FVC, had a significant negative association with short-term exposure to O(3) and PM(10) measured on the day of spirometry testing. FVC values also were reversely associated with means of SO(2), O(3), NO(2), PM(10) and CO exposed 1 d earlier. An increase of 1-ppm CO was associated with the reduction in FVC for 69.8 mL (95% CI: -115, -24.4 mL) or in FEV(1) for 73.7 mL (95% CI: -118, -29.7 mL). An increase in SO(2) for 1 ppb was associated with the reductions in FVC and FEV(1) for 12.9 mL (95% CI: -20.7, -5.09 mL) and 11.7 mL (95% CI: -19.3, -4.16 mL), respectively. In conclusion, the short-term exposure to O(3) and PM(10) was associated with reducing FVC and FEV(1). CO and SO(2) exposure had a strong 1-d lag effect on FVC and FEV(1).

Higher body mass index may induce asthma among adolescents with pre-asthmatic symptoms: a prospective cohort study.

BACKGROUND: Limited studies have prospectively examined the role of body mass index (BMI) as a major risk factor for asthma during adolescence. This study investigates whether BMI is associated with increased risk of developing physician-diagnosed asthma during 12-month follow-up among adolescents with undiagnosed asthma-like symptoms at baseline. METHODS: A total of 4,052 adolescents with undiagnosed asthma-like symptoms at baseline were re-examined after a 12-month follow-up. Asthma cases were considered confirmed only after diagnosis by a physician based on the New England core and International Study of Asthma and Allergies in Childhood (ISAAC) criteria video questionnaires, and accompanying pulmonary function tests. Logistic regression analyses were used to evaluate the relationship of BMI and the risk of acquiring asthma. RESULTS: The results indicated that girls with higher BMI were at an increased risk of developing asthma during the 12-month follow-up. The odds ratios for girls developing physician-diagnosed asthma were 1.75 (95% CI = 1.18-2.61) and 1.12 (95% CI = 0.76-1.67), respectively, for overweight and obesity as compared to the normal weight reference group after adjustment for other covariates. A similar relationship was not observed for overweight and obese boys who were also significantly more active than their female counterparts. CONCLUSIONS: Increased BMI exaggerates the risk of acquiring asthma in symptomatic adolescent females but not in adolescent males. Thus, gender is an important modifier of BMI-related asthma risk. Additional research will be required to determine whether the increased asthma risk results from genetic, physiological or behavioural differences.

Assessing the quality of tuberculosis-related underlying cause of death assignment in Taiwan, 2001-2005.

BACKGROUND/PURPOSE: Assignment of underlying cause of death (UCOD) might be inconsistent among coders if physicians do not properly record cause of death on death certificates. This study aimed to assess the changes in the quality of tuberculosis-related UCOD assignment in Taiwan after interventions by the Center for Disease Control (CDC). METHODS: The reference (gold standard) we used to assess the quality of UCOD assignment by coders was the UCOD selected by the Automated Classification of Medical Entities (ACME) computer program. The agreement, over- and under-coding rates between coders and the reference were calculated by years before and after the CDC interventions. RESULTS: An abrupt decrease in tuberculosis death rates according to the UCOD assigned by coders was noted from 2003 to 2004, but no such decrease was noted according to the reference. The agreement in UCOD assignments between coders and ACME decreased from 0.75 in 2001 to 0.67 in 2005. We found a significant decrease in the over-coding rate from 0.21 in 2003 to 0.11 in 2004, and a prominent increase in under-coding rates from 0.08 in 2003 to 0.24 in 2004. CONCLUSION: The abrupt decrease in the official published tuberculosis mortality rate from 2003 to 2004 was due to significant changes in the practice of UCOD assignment of official coders, which might have been a response to interventions initiated by the CDC.

Air pollution, weather, and associated risk factors related to asthma prevalence and attack rate.

Asthma is an important public health challenge. The objective of this research was to investigate the relationship of air pollution and weather to adolescent asthma prevalence and attack rate. A 6-month mass screening asthma study was conducted from October 1995 to March 1996 in Taiwan. The study population included junior high school students from throughout the country (1,139,452 students). Eighty-nine percent of students completed questionnaires (International Study of Asthma and Allergies in Childhood-ISAAC and New England Core Questionnaires) and passed a logical screening error program. Lung function data was collected to assist in the diagnosis of asthma status. From the students screened during this mass survey, a stratified random sample of 64,660 students was analyzed for asthma prevalence and attack rate. Using a regression model to compare the USEPA National Ambient Air Quality Standards 2000 (NAAQS, 2000) to asthma prevalence, this investigation found that the standards may not provide enough protection for adolescents after controlling for age, rhinitis, eczema, urban birth location, parental education level, exercise, cigarette smoking, environmental tobacco smoking, alcohol beverage consumption and weather factors. The general estimating equations (GEE) model, a repeated measurement regression model, was used to examine the relationship between the monthly asthma attack rate among asthma patients and air pollution (nitrogen oxides; nitrogen dioxide; nitric oxide; Ozone; PM10) while controlling for household smoking. The GEE model demonstrated that air pollution is related to asthma attack rate. Air pollution factors also interacted with weather parameters when related to asthma attack rate.

Intervals before tuberculosis diagnosis and isolation at a regional hospital in Taiwan.

BACKGROUND/PURPOSE: Nosocomial tuberculosis (TB) infection is still a problem in many Taiwanese hospitals. The objectives of this study were to explore the intervals before TB diagnosis and isolation at a regional hospital in Taiwan, and to provide useful knowledge to hospitals for the purpose of TB infection control. METHODS: From 2002 to 2005, we included a total of 343 patients with culture-positive pulmonary TB in a regional hospital in Southern Taiwan for this study. Their medical records were reviewed, and the time intervals between patient-hospital contact points and isolation were recorded. RESULTS: Of 343 culture-positive pulmonary TB patients, the majority were male, over 40 years old, and unemployed. The mean interval between the first admission and isolation was 20.5 days (median, 2.0 days). The mean intervals between the first admission from outpatient clinics, emergency department and hospitalization and suspected TB were < 1 day, 6.07 days and 25.53 days, respectively. The mean accumulated exposure time was 0.35 days, 0.61 days and 10.09 days in outpatient clinics, the emergency department and hospitalization, respectively; 75.5% of patients had their diagnosis confirmed at the chest department of the department of internal medicine. CONCLUSION: Delayed diagnosis was most likely in the case of hospitalized patients and least likely in outpatient clinics. Delayed diagnosis in hospitalized patients also contributed more severely to TB exposure time than others. Enhancing the quality, speed and ability of specialists and physicians to diagnose TB, especially in emergency departments and in hospitalized patients, is essential.

Association of HLA class I with severe acute respiratory syndrome coronavirus infection.

BACKGROUND: The human leukocyte antigen (HLA) system is widely used as a strategy in the search for the etiology of infectious diseases and autoimmune disorders. During the Taiwan epidemic of severe acute respiratory syndrome (SARS), many health care workers were infected. In an effort to establish a screening program for high risk personal, the distribution of HLA class I and II alleles in case and control groups was examined for the presence of an association to a genetic susceptibly or resistance to SARS coronavirus infection. METHODS: HLA-class I and II allele typing by PCR-SSOP was performed on 37 cases of probable SARS, 28 fever patients excluded later as probable SARS, and 101 non-infected health care workers who were exposed or possibly exposed to SARS coronavirus. An additional control set of 190 normal healthy unrelated Taiwanese was also used in the analysis. RESULTS: Woolf and Haldane Odds ratio (OR) and corrected P-value (Pc) obtained from two tails Fisher exact test were used to show susceptibility of HLA class I or class II alleles with coronavirus infection. At first, when analyzing infected SARS patients and high risk health care workers groups, HLA-B*4601 (OR = 2.08, P = 0.04, Pc = n.s.) and HLA-B*5401 (OR = 5.44, P = 0.02, Pc = n.s.) appeared as the most probable elements that may be favoring SARS coronavirus infection. After selecting only a "severe cases" patient group from the infected "probable SARS" patient group and comparing them with the high risk health care workers group, the severity of SARS was shown to be significantly associated with HLA-B*4601 (P = 0.0008 or Pc = 0.0279). CONCLUSIONS: Densely populated regions with genetically related southern Asian populations appear to be more affected by the spreading of SARS infection. Up until recently, no probable SARS patients were reported among Taiwan indigenous peoples who are genetically distinct from the Taiwanese general population, have no HLA-B* 4601 and have high frequency of HLA-B* 1301. While increase of HLA-B* 4601 allele frequency was observed in the "Probable SARS infected" patient group, a further significant increase of the allele was seen in the "Severe cases" patient group. These results appeared to indicate association of HLA-B* 4601 with the severity of SARS infection in Asian populations. Independent studies are needed to test these results.

National surveillance for type 2 diabetes mellitus in Taiwanese children.

CONTEXT: Despite a disturbing trend of increasing prevalence of type 2 diabetes mellitus (DM) in childhood, little is known about the epidemiology of childhood type 2 DM, especially in the Taiwanese population. OBJECTIVE: To study the rate and risk factors for childhood type 2 DM based on a nationwide screening program in Taiwan. DESIGN, SETTING, AND PARTICIPANTS: Screening in 1999 for type 2 DM using urine and blood testing and confirmed by follow-up telephone survey among schoolchildren aged 6 to 18 years in Taiwan, followed by a nested case-control study conducted in 2002 comparing 137 children with type 2 DM with 1,000 randomly selected children without diabetes chosen to represent the age and sex distribution of the whole student population. MAIN OUTCOME MEASURES: Rate and identification of risk factors associated with childhood type 2 DM. RESULTS: The rate of newly identified diabetes was 9.0 per 100,000 for boys and 15.3 per 100,000 for girls. Follow-up at 3 years revealed that, of 253 children with newly diagnosed diabetes, 24 (9.5%) had type 1 DM, 137 (54.2%) had type 2 DM, and 22 (8.7%) had secondary diabetes. Compared with children aged 6 to 9 years, the odds ratios (ORs) and 95% confidence intervals (CIs) of type 2 DM increased to 6.59 (3.23-13.4) for those aged 13 to 15 years and to 4.59 (2.07-10.2) for those aged 16 to 18 years. The OR (95% CI) of type 2 DM in children with a body mass index in the 95th percentile or higher (obesity) was 18.8 (9.22-38.5) compared with those with a body mass index in less than the 50th percentile. Other factors significantly associated with type 2 DM were hypercholesterolemia (OR, 1.80; 95% CI, 1.04-3.23), blood pressure greater than the 85th percentile (OR, 1.70; 95% CI, 1.07-2.70), and positive family history of diabetes (OR, 3.95; 95% CI, 2.01-7.78). CONCLUSIONS: Our mass screening program showed that type 2 DM is the leading cause of childhood DM in Taiwan. Obesity is a major risk factor for the development of type 2 DM in children.

Cost-benefit analysis of routine childhood vaccination against chickenpox in Taiwan: decision from different perspectives.

Cost-benefit analysis was conducted to determine whether it is worthwhile to initiate a routine varicella vaccination program in Taiwan from different perspectives. Using the human capital approach, the discounted net cost for vaccination program was New Taiwan Dollars (NTD) 281 million from health care payer's perspective. Taking indirect costs into account, the net saving due to vaccination program was NTD 425 million from the societal perspective. In terms of benefit-cost ratio, a mass varicella vaccination program could only save NTD 0.34 in discounted costs for each dollar incurred in a vaccination program from health care payer's perspective whereas save NTD 2.06 from the societal viewpoint. Results based on the willingness-to-pay (WTP) method showed the Net Present Value (NPV) of the vaccination program was estimated as -NTD 272 million. We conclude that a routine varicella vaccination program is worthwhile from the societal perspective but neither from health care payer's nor from consumer decision based on the perspective of WTP.

Childhood diabetes identified in mass urine screening program in Taiwan, 1993-1999.

OBJECTIVE: To describe the gender differences in cases and characteristics of diabetes mellitus (DM) that can be identified from a mass urine screen program for school children in Taiwan. METHOD: Screening for the childhood asymptomatic proteinuria and glucosuria began in 1992 for school children. Students were instructed to collect mid-stream samples of the first morning urine for glucosuria and proteinuria tests using urine strip devices. Students with positive results for glucose and/or protein and/or occult blood in the first examination received a second urine test. The third screening test was performed for urine and fasting blood sample for 11-item examinations if the second test was positive. The 1997 criteria of American Diabetes Association were used for defining DM. RESULTS: Approximately 2,615,000-2,932,000 students received the preliminary screening each semester. The overall average rates of newly identified diabetes from 1993 to 1999 were 8.3 per 100,000 among boys, and 12.0 per 100,000 among girls. The average rate of new cases increased significantly from sixth grade for boys and fourth grade for girls, with peak rates of 14.7 per 100,000 in eighth grade for boys and 19.0 per 100,000 in sixth grade for girls. Similar prevalence trends by sex and grade were observed, higher in girls than in boys. CONCLUSIONS: This mass screening data suggest that childhood diabetes of all types in Taiwan is elevated in the age of puberty and higher in girls than in boys.

Outbreak of Stevens-Johnson syndrome/toxic epidermal necrolysis associated with mebendazole and metronidazole use among Filipino laborers in Taiwan.

OBJECTIVES: This study sought to identify the risk factors associated with an outbreak of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) among Filipino laborers in Taiwan. METHODS: Forty-six SJS/TEN patients were matched to 92 controls according to month of arrival in Taiwan, sex, and age. RESULTS: The odds ratio for development of SJS/TEN was 9.5 (95% confidence interval [CI] = 3.9, 23.9) among workers who had used both metronidazole and mebendazole sometime in the preceding 6 weeks. In addition, a gradient increase in the occurrence of SJS/TEN was found with an increasing level of exposure to metronidazole. CONCLUSIONS: This outbreak highlights the risk of SJS/TEN resulting from the use of both metronidazole and mebendazole and the need for control measures.

Low birth weight and high birth weight infants are both at an increased risk to have type 2 diabetes among schoolchildren in taiwan.

OBJECTIVE: To study the effect of birth weight on risk of type 2 diabetes in the schoolchildren in Taiwan. RESEARCH DESIGN AND METHODS: From 1992 to 1997, all schoolchildren aged 6-18 years were screened for diabetes in Taiwan Province. This cohort consisted of 1,966 patients with diabetes and 1,780 randomly selected subjects with normal fasting glycemia (NFG). Questionnaire interviewing was designed to classify diabetes. The birth weight was obtained from the Taiwan's Birth Registry. After merging the data, there were 978 subjects, including 429 with type 2 diabetes and 549 with of NFG enrolled in the present analyses. RESULTS: The odds ratios (95% CI) for type 2 diabetes, after adjusting age, sex, BMI, family history of diabetes, and socioeconomic status, were 2.91 (1.25-6.76) for children with low birth weight (<2,500 g) and 1.78 (1.04-3.06) for those with high birth weight (> or =4,000 g) when compared with the referent group (birth weight 3,000-3,499 g). The risk of diabetes was still 64% higher in the high birth weight group [odds ratio (OR) 1.64 (95% CI 0.91-2.96)], even after adjustment for gestational diabetes mellitus (GDM). Patients with type 2 diabetes who were born with high birth weight were more likely to have a higher BMI and diastolic blood pressure as well as a higher family history of diabetes compared with those with low birth weight. CONCLUSIONS: A U-shaped relationship between birth weight and risk of type 2 diabetes was found in the schoolchildren aged 6-18 years in Taiwan. Schoolchildren with type 2 diabetes who were born with low birth weight had different metabolic phenotypes compared with those born with high birth weight.

Residential exposure to power frequency magnetic field and sleep disorders among women in an urban community of northern Taiwan.

STUDY OBJECTIVES: To investigate relationships between residential exposure to power frequency magnetic field and sleep initiation and maintenance disorders (SIAMD). DESIGN: A cross-sectional design conducted in an urban town of northern Taiwan in 1995-1996. SETTING/PATIENTS: A total of 5,078 married women aged 20-59. INTERVENTIONS: N/A. MEASUREMENTS: The residential magnetic field intensity was assessed using EMDEX II dosimeters. Trained interviewees collected self-reported information on SIAMD and other covariates. Three type-specific SIAMD were analyzed for associations with background, bedroom, and overall residential exposures. RESULTS: The prevalence rates of difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), and early morning awakening (EMA) were 29.5%, 38.17%, and 26.02%, respectively. The DIS prevalence was significantly associated with bedroom magnetic field exposure of 2 miliGauss (mG) (odds ratio (OR)=1.20, 95% confidence interval (CI)=1.02-1.40). The DMS prevalence was significantly higher for women with background exposure of 2 mG (OR=1.28, 95% CI=1.04-1.56). An elevated EMA prevalence was also significantly associated with all of the three exposure measures with excess risks ranging from 28% for overall exposure to 65% for background exposure. When magnetic field strength was analyzed as a continuous variable, background exposure, but not overall or bedroom exposure, showed a small but significant association with DMS and EMA (OR=1.05 per 1 mG increase, 95% CI=1.02-1.09). CONCLUSIONS: There is a modest association between residential exposures to elevated magnetic field intensity and insomnia complaints in women.