Assessing the impact of specific PM2.5-Bound metallic elements on asthma emergency department visits: A case-crossover study in Taiwan.

OBJECTIVES: This study aims to assess the specific PM2.5-bound metallic elements that contribute to asthma emergency department visits by using a case-crossover study design. METHODS: This study analyzed data from 11,410 asthma emergency department visits as case group and 22,820 non-asthma onset dates occurring one week and two weeks preceding the case day as controls from 2017 to 2020. PM2.5 monitoring data and 35 PM.2.5-bound metallic elements from six different regions in Taiwan were collected. Conditional logistic regression models were used to assess the relationship between asthma and PM2.5-bound metallic elements. RESULTS: Our investigation revealed a statistically significant risk of asthma emergency department visits associated with PM2.5 exposure at lag 0, 1, 2, and 3 during autumn. Additionally, PM2.5-bound hafnium (Hf), thallium (Tl), rubidium (Rb), and aluminum (Al) exhibited a consistently significant positive correlation with asthma emergency department visits at lags 1, 2, and 3. In stratified analyses by area, age, and sex, PM2.5-bound Hf showed a significant and consistent correlation. CONCLUSIONS: This study provides evidence of PM2.5-bound metallic elements effects in asthma exacerbations, particularly for Hf. It emphasizes the importance of understanding the origins of these metallic elements and pursuing emission reductions to mitigate regional health risks.

Assessing the effectiveness of mitigating pesticide-related disease risk among pesticide-spraying drone operators in Taiwan.

OBJECTIVES: The purpose of this study was to evaluate the risk of pesticide poisoning, liver and renal failure, dermatitis, respiratory problems, hypersensitivity pneumonitis, keratitis, and epilepsy among pesticide-spraying personnel and to assess the effectiveness of a new method of aerial pesticide application in reducing this risk. METHODS: A total of 2268 pesticide spraying operators (1651 ground-based field crop operators and 617 aerial pesticide spraying drone operators) who passed the national certification examination between 2010 and 2020 in Taiwan were included. Ground-based operators served as the positive control group, while 2463 farmer controls were matched from the Farmers' Health Insurance database as the negative control group. Data from the National Health Insurance Research Database were used to track possible pesticide-related disease cases. Logistic regression was employed to calculate odds ratios and 95% confidence intervals (95% CI). RESULTS: Drone operators had significantly reduced risks of dermatitis, asthma and chronic bronchitis compared to ground-based operators. This was observed in allergic contact dermatitis (OR = 0.40, 95% CI: 0.24-0.68), unspecified contact dermatitis (OR = 0.58, 95% CI: 0.35-0.97), asthma (OR = 0.27, 95% CI: 0.12-0.60), and chronic bronchitis (OR = 0.24, 95% CI: 0.06-0.93), after adjusting for age, sex, working areas, and licensing years. However, no significant differences were found when comparing drone operators to matching farmers. CONCLUSIONS: Aerial pesticide spraying using drones may contribute to a decreased risk of dermatitis, asthma and chronic bronchitis, suggesting potential health benefits for operators. Further field pesticide exposure surveys are recommended to validate these findings and assess health risk indicators.

Upcoming epidemic of asbestos-related malignant pleural mesothelioma in Taiwan: A prediction of incidence in the next 30 years.

BACKGROUND/PURPOSE: Globally, asbestos-related diseases (ARDs) keep rising over the coming decades. The epidemic of ARDs will be a burden on public health. We aimed to predict the malignant pleural mesothelioma (MPM) incidence in the next 30 years for Taiwan based on historical asbestos consumption. METHODS: We collected annual data on local asbestos consumption during 1939-2015 and sex-specific incidence of pleural cancer as a proxy for MPM during 1979-2013. We applied Poisson log-linear models to predict future MPM numbers under the assumption that latency periods between asbestos exposure and MPM incidence were between 25 and 45 years. RESULTS: Asbestos consumption reached a peak in the 1980s, with a total of 668 thousand metric tons during 1939-2015. The observed number of MPM incidence increased by 9- and 6-fold in males and females during 1979-2013, with a cumulative number of 907. Given a latency period of 31 years, MPM incidences were expected to peak around 2012-2016 for males and 2016-2020 for females. In 2017-2046, the predicted total number of new MPM might reach 659 cases (95% confidence interval = 579-749); and the male to female ratios ranged from 1.8 to 2.8. CONCLUSION: The MPM epidemic in Taiwan will likely peak in 2012-2020 as a result of local asbestos consumption. Approximately 659 new MPM cases in the next 30 years warrant an urgent need to implement a total asbestos ban and put more resources on a comprehensive surveillance, diagnosis, and follow-up health care system for ARDs.

Characterization of genes encoding proteins containing HD-related output domain in Xanthomonas campestris pv. campestris.

The Gram-negative plant pathogen Xanthomonas campestris pv. campestris (Xcc) is the causative agent of black rot in crucifers. The production of Xcc virulence factors is regulated by Clp and RpfF. HD-related output domain (HDOD) is a protein domain of unknown biochemical function. The genome of Xcc encodes three proteins (GsmR, HdpA, and HdpB) with an HDOD. The GsmR has been reported to play a role in the general stress response and cell motility and its expression is positively regulated by Clp. Here, the function and transcription of hdpA and hdpB were characterized. Mutation of hdpA resulted in enhanced bacterial attachment. In addition, the expression of hdpA was positively regulated by RpfF but not by Clp, subject to catabolite repression and affected by several stress conditions. However, mutational analysis and reporter assay showed that hdpB had no effect on the production of a range of virulence factors and its expression was independent of Clp and RpfF. The results shown here not only extend the previous work on RpfF regulation to show that it influences the expression of hdpA in Xcc, but also expand knowledge of the function of the HDOD containing proteins in bacteria.

Climate Change Projections for Stroke Incidence in Taiwan: Impact of 2 °C and 4 °C Global Warming Level.

OBJECTIVES: This study aimed to establish the exposure-lag-response effect between daily maximum temperature and stroke-related emergency department visits and to project heat-induced stroke impacts under global warming levels (GWL) of 2 °C and 4 °C. METHODS: Stroke-related emergency department visits in Taiwan from 2001 to 2020 were identified using the National Health Insurance Research Database (NHIRD). The study population consisted of 1,100,074 initial stroke cases matched with 2,200,148 non-stroke controls. We employed Distributed Lag Nonlinear Models (DLNM) in a case-crossover study to investigate the association between temperature and stroke. Generalized Estimating Equations (GEE) models with a Poisson function were used to correlate high-temperature exposure with annual stroke incidence rates. Projections were made under two global warming scenarios, GWL 2.0 °C and 4.0 °C, using Coupled General Circulation Model (GCMs). Baseline data from 1995 to 2014 were transformed for spatial distribution at the township level. Geographic Information System (GIS) spatial analysis was performed using Quantum GIS 3.2.0 software. RESULTS: DLNM exposure-lag-response effect revealed that daily maximum temperature exceeding 34 °C significantly increased the risk of stroke-related emergency department visits, particularly for ischemic stroke. Under the 2 °C GWL scenario, the frequency of days with temperatures surpassing 34 °C is projected to rise substantially by the median year of 2042, with a further increase to 92.6 ± 18.0 days/year by 2065 under the 4 °C GWL scenario. Ischemic stroke showed the highest increase in temperature-related incidence rates, notably rising from 7.80% under the GWL 2 °C to 36.06% under the GWL 4 °C. Specifically, the annual temperature-related incidence rate for ischemic stroke is expected to increase significantly by 2065. Regions such as Taichung, Hsinchu, Yilan, and Taitung demonstrated pronounced changes in heat-related ischemic stroke incidence under the GWL 4 °C. CONCLUSIONS: The findings emphasize the importance of addressing temperature-related stroke risks, particularly in regions projected to experience significant temperature increases. Effective mitigation strategies are crucial to reduce the impact of rising temperatures on stroke incidence and safeguard public health.

Estimating quality weights for EQ-5D (EuroQol-5 dimensions) health states with the time trade-off method in Taiwan.

BACKGROUND/PURPOSE: EQ-5D (EuroQol-5 dimensions) is a preference-based measure of health, which is widely used in cost-utility analyses. It has been suggested that each country should develop its own value set. We therefore sought to develop the quality weights of the EQ-5D health states with the time trade-off (TTO) method in Taiwan. METHODS: A total of 745 respondents consisting of employees and volunteers in 17 different hospitals were recruited and interviewed. Each of them valued 13 of 73 EQ-5D health states using the TTO method. Based on the three exclusion criteria for valuation data, only 456 (61.21%) respondents were considered eligible for data analysis. The quality weights for all EQ-5D health states were modeled by generalized estimating equations (GEEs). RESULTS: Over half of the responses were given negative values, and the medical personnel seemed to have a significantly higher TTO value (+0.1) than others after controlling for other predictors. The N3 model (level 3 occurred within at least 1 dimension) yielded an acceptable fit for the observed OTT data [mean absolute error (MAE) = 0.056, R(2) = 0.35]. The magnitude of mean absolute differences (MADs) between Taiwan data and those from the UK, Japan, and South Korea ranged from 0.146 to 0.592, but the rank correlation coefficients were all above 0.811. CONCLUSION: This study reaffirms the differences in health-related preference values across countries. The high proportion of negative values might indicate that we have also partially measured the intensity of fear in addition to the utility of different health states.

Estimation of benefit of prevention of occupational cancer for comparative risk assessment: methods and examples.

OBJECTIVES: To quantify the life years gained and financial savings by preventing a case of occupational cancer. METHODS: The authors retrieved data from the Taiwan Cancer Registry and linked them with the National Mortality Registry to estimate the survival functions for major occupational cancers: lung, pleural mesothelioma, urinary bladder and leukaemia. Assuming a constant excess hazard for each type of cancer, the authors extrapolated lifetime survival functions by the Monte Carlo method. For each patient with cancer, the authors simulated an age- and gender-matched person without cancer based on vital statistics of Taiwan to estimate life expectancy and expected years of life lost (EYLL). By using the reimbursement data from the National Health Insurance Research Database, the authors calculated the average monthly healthcare expenditures, which were summed to estimate the lifetime healthcare expenditures after adjusting for the corresponding monthly survival probability. RESULTS: A total of 51,408, 136, 12,891 and 5285 new cases of lung, pleural mesothelioma, bladder and leukaemia cancers, respectively, were identified during 1997-2005 and followed until the end of 2007. The EYLL was predicted to be 13.7±0.1, 18.9±0.7, 4.7±0.3 and 19.4±0.5 years for these cancers, respectively, and the lifetime healthcare expenditures with a 3% annual discount were predicted to be US$22,359, US$14,900, US$51,987 and US$59,741, respectively. CONCLUSIONS: The burden of these occupational cancers, in terms of EYLL and lifetime healthcare expenditures, was substantial. Such estimates may provide useful empirical evidence for comparative risk assessment that can be applied in health policy-making and clinical decision-making.

Polycystic kidney disease increases the stoke incidence in Taiwan: A retrospective population-based cohort study using National Health Insurance Database.

BACKGROUND: Few studies documented incidence rates of different types of stroke among patients with polycystic kidney disease (PKD). METHODS: We conducted a retrospective cohort study based on the National Health Insurance (NHI) Database of Taiwan. The PKD cohort comprised patients aged≥20 years diagnosed with PKD using inpatient claims from 1998 to 2011, excluding prior stroke. The reference cohort was established by inpatients without PKD using 1:4 frequency-matched with age, gender, and baseline comorbidities. The two cohorts were followed-up until stroke hospitalization, death, withdrawal from the NHI program, or the end of 2012. To account for competing risks of death, we used multivariable competing risks regression models to estimate sub-distribution hazard ratio (SHR) adjusted for age, gender, baseline comorbidities and end stage renal disease. RESULTS: 7837 PKD patients and 31,211 reference subjects were followed up through 2012. A total of 955 cases of stroke were identified in the PKD cohort, including 441 ischemic stroke (IS), 289 intracranial hemorrhage (ICH), 73 subarachnoid hemorrhage (SAH) and 232 other stroke. The incidence rates of overall stroke, IS, ICH, and SAH were 21.3, 10.2, 6.8, and 1.7 per 1000 person-years, respectively. The SHR for overall stroke was 1.39 [95% confidence interval (CI) 1.28-1.50]. SAH had the highest SHR, 4.55 [95% CI 3.26-6.37], followed by ICH (1.84), other stroke (1.24), and IS (1.22). CONCLUSION: This study illustrated the incidence rates of stroke among inpatient of PKD. The PKD patients had a significantly increased risk of all kinds of stroke after adjusting baseline comorbidities.

Mortality from liver cancer and leukaemia among polyvinyl chloride workers in Taiwan: an updated study.

OBJECTIVES: To investigate types of cancer caused by occupational exposure to vinyl chloride monomer (VCM) and the temporal mortality trends of these cancers in workers from polyvinyl chloride (PVC) manufacturing factories in Taiwan, with follow-up of the cohort extended by 15 years, from 1980 to 2007. Methods A retrospective cohort study of workers from six PVC factories in Taiwan was conducted. 3336 male PVC workers were enrolled and further linked with the National Mortality Registry and National Household Registry databases. Standardised mortality ratios (SMR) with 95% CIs were calculated and compared to the general Taiwanese male population. Cause-specific mortality between two study periods, 1980-1997 and 1998-2007, was compared. Six-year moving averages of the SMRs were calculated to examine mortality trends. RESULTS: Liver cancer mortality increased during 1989-1994 (SMR 1.90, 95% CI 1.01 to 3.25), reached a peak during 1991-1996 (SMR 2.31, 95% CI 1.39 to 3.61) and became non-significant during 1994-1999 (SMR 1.42, 95% CI 0.80 to 2.34). Leukaemia mortality significantly increased during 1984-1989 (SMR 6.06, 95% CI 1.24 to 17.53), reached a peak during 1985-1990 (SMR 7.56, 95% CI 2.06 to 19.35) and became non-significant during 1991-1996 (SMR 3.24, 95% CI 0.39 to 11.69). The mortality trend for haemolymphopoietic cancer showed a similar pattern to that of leukaemia. CONCLUSIONS: VCM may increase the risk of liver cancer and leukaemia. When VCM exposure was controlled at worksites, mortality from these cancers returned to background levels.

Comparison of the quality of life between patients with non-small-cell lung cancer and healthy controls.

PURPOSE: We explored covariates of the quality of life (QOL) in non-small-cell lung cancer (NSCLC) patients and made a comparison with healthy controls. METHODS: We assessed the QOL of 220 consecutive NSCLC patients at a university hospital. The QOL data were measured by the brief version of the World Health Organization's Quality of Life and by utility using the standard gamble method. We selected demographically matched healthy controls from the 2001 National Health Interview Survey for comparison. Multiple linear regression models were constructed to explore significant factors of QOL after controlling for covariates. RESULTS: Patients with more advanced stages of NSCLC had poorer scores than did the healthy controls in the physical and psychological domains. Patients with disease duration of longer than 1 year tended to report higher physical and environment QOL than did those with NSCLC diagnosed for less than 1 year. Insight into one's own illness was associated with a higher utility, better social support, and improved financial resources. CONCLUSIONS: QOL was significantly associated with staging and duration of NSCLC. Disease insight appears to be a positive factor for operable NSCLC patients of the Taiwanese culture, which implies that clinicians should respect patient autonomy in diagnosis disclosure.

Health impact of pneumoconiosis in Mongolia: estimation of losses in life expectancy and quality adjusted life expectancy.

OBJECTIVE: To estimate the life expectancy (LE), quality-adjusted life expectancy (QALE), and their losses, in patients with pneumoconiosis in Mongolia. METHODS AND MATERIALS: All patients (n = 432) diagnosed with occupational pneumoconiosis during 1986-2006 were recruited from the registry of the National Research Center of Occupational Diseases, which was linked to the National Mortality Registry of Mongolia to obtain the survival function. We simulated age and gender matched referents group based on the life table in 2000. The survival ratio between patients and referents was used to extrapolate and calculate the LE. The average expected years of life loss (EYLL) of pneumoconiosis were calculated as the mean survival difference between patients and referents. We adopted utility values for workers with pneumoconiosis and multiplied them with the survival function to estimate the QALE, which was then used to calculate the loss of QALE. RESULTS: The life expectancy and EYLL of a patient with pneumoconiosis were 18.1 and 9.5 years respectively. QALE and loss of QALE were 15.1 and 12.5 QALYs (quality-adjusted life years), respectively, indicating a health gap of 45%. CONCLUSION: The health inequality suffered by miners in Mongolia must be addressed through prevention, including exposure monitoring and control, early diagnosis and case management and rehabilitation of pneumoconiosis.

Increased Risk of Gastric Cancer in Asbestos-Exposed Workers: A Retrospective Cohort Study Based on Taiwan Cancer Registry 1980-2015.

Asbestos has been recognized as a human carcinogen associated with malignant mesothelioma, cancers of lung, larynx, and ovary. However, a putative association between gastric cancer and asbestos exposure remains controversial. In this study, we aimed to explore gastric cancer risk of workers potentially exposed to asbestos in Taiwan. The asbestos occupational cohort was established from 1950 to 2015 based on the Taiwan Labor Insurance Database, and Taiwan Environmental Protection Agency regulatory datasets, followed by the Taiwan Cancer Registry for the period 1980-2015. Standardized incidence ratios (SIRs) for cancer were computed for the whole cohort using reference rates of the general population, and also reference labor population. Compared with the general population, SIR of the asbestos occupational cohort for the gastric cancer increased both in males (1.05, 95% confidence interval (CI): 1.02-1.09) and females (1.10, 95% CI: 1.01-1.18). A total of 123 worksites were identified to have cases of malignant mesothelioma, where increased risk for gastric cancer was found with a relative risk of 1.76 (95% CI: 1.63-1.90). This 35-year retrospective cohort study of asbestos-exposed workers in Taiwan may provide support for an association between occupational exposure to asbestos and gastric cancer.

Increased mortality risk for workers with a compensated, permanent occupational disability of the upper or lower extremities: a 21-year follow-up study.

This 1986-2006 study sought to determine whether specific causes led to increased mortality risks for Taiwanese workers with an approved compensation claim for permanent occupational disability (ACCPOD) of the upper or lower extremities. All cases of ACCPOD between 1986 and 2006 were collected from the database of compensation claims at the Bureau of Labor Insurance. Standardized mortality ratios and 95% confidence intervals were calculated for different causes of death among workers with an ACCPOD of the upper or lower extremities. A total of 800,047 person-years were accrued for 71,001 workers with a single type of disability. Standardized mortality ratios were significantly increased for all causes, including liver cirrhosis, injuries, and intentional self-harm. Standardized mortality ratios for workers with amputations of the lower extremities increased to 7.66 (95% confidence interval (CI): 5.36, 10.61), 2.40 (95% CI: 1.44, 3.75), 2.07 (95% CI: 1.03, 3.70), and 5.09 (95% CI: 2.20, 10.03) for those with diabetes mellitus, cerebrovascular disease, liver cirrhosis, and chronic renal failure, respectively. The authors concluded that workers with occupational disabilities involving an upper or lower extremity should be assisted to prevent further injuries or intentional self-harm, whereas those with lower limb amputations should be provided care related to proactive control of diabetes mellitus and associated complications during rehabilitation.

Life expectancy, expected years of life lost and survival of hemodialysis and peritoneal dialysis patients.

BACKGROUND: Expected years of life lost (EYLL) in dialysis patients are rarely discussed. This study compared life expectancy, EYLL and survival between hemodialysis (HD) and peritoneal dialysis (PD) patients. METHODS: Adults who underwent maintenance dialysis at National Taiwan University Hospital from 1995 to 2006 were followed up until December 2007. Kaplan-Meier analysis and a constant excess hazard model were used to estimate and project long-term survival. EYLL was calculated by subtracting the life expectancy of patients from that of age- and sex-matched referents. HD patients were then matched with PD patients on age, sex and diabetes mellitus (DM). Life expectancy, EYLL and survival between the 2 groups were compared. Mortality risks were determined by the Cox model. RESULTS: Before matching, the 305 HD patients were older than the 428 PD patients (62.4 ± 13.7 vs. 53.1 ± 16.7 years; p<0.0001). More HD patients had DM (HD vs. PD, 29.2% vs. 20.6%; p=0.0072). Life expectancy and EYLL of HD patients were 8.8 and 11.5 years, compared with those of PD patients (19.9 and 7.4 years). After matching, life expectancy (p=0.790) and EYLL (p=0.793) of both groups (236 patients each) were similar. Age (adjusted hazard ratio [AHR] = 1.07; 95% confidence interval [95% CI], 1.05-1.09) and DM (AHR=3.81; 95% CI, 2.28-6.36) were independent mortality predictors. For diabetic patients who underwent HD, a better survival rate was observed (AHR=0.24; 95% CI, 0.11-0.53). CONCLUSIONS: After matching, HD and PD patients had similar life expectancy and EYLL. Survival was better for diabetic patients if they received HD.

Estimation of life expectancy and the expected years of life lost in patients with major cancers: extrapolation of survival curves under high-censored rates.

OBJECTIVES: There exists a lack of extrapolation methods for long-term survival analysis when censored rates are high (25-50%). This study aimed at estimating life expectancy (LE) after the diagnosis of cancer and the expected years of life lost (EYLL) using a newly developed semiparametric method. METHODS: Patients (n = 425,294) diagnosed with 17 different types of major cancer were enrolled. All of the patients were registered with the Taiwan Cancer Registry between 1990 and 2001; their survivals were followed through the end of 2004. The survival function for an age- and sex-matched reference population was generated using the Monte Carlo method from the life table of the general population. Lifetime survival of the cancer patients (up to 50 years) were obtained using linear extrapolation of a logit-transformed curve of the survival ratio between the cancer and reference populations. The estimates were compared with the results from the extrapolation of fitted Weibull models. RESULTS: The 15-year survival, LE, and EYLL for 17 different types of cancer were determined, of which the LE of breast, cervical, ovarian, and skin cancers exceeded 15 years; nasopharyneal, leukemia, bladder, kidney, and colorectal cancers exceeded 10 years. Validity tests indicated that the relative biases of the extrapolated estimates were usually <5% under high censoring rates. CONCLUSIONS: The newly developed method is feasible and relatively accurate to project LE and EYLL, which could also be merged with data pertaining to quality of life, for a more detailed outcome assessment in the future.

Increased risk of death with congenital anomalies in the offspring of male semiconductor workers.

Female workers in the semiconductor industry have higher risks of subfertility and spontaneous abortion, but no studies exploring male-mediated developmental toxicity have been published. This study aimed to investigate whether the offspring of male workers employed in the semiconductor manufacturing industry had an increased risk of death with congenital anomalies. The 6,834 male workers had been employed in the eight semiconductor companies in Taiwan between 1980 and 1994. We identified the live born children with or without congenital anomalies of the workers using the National Birth and Death Registries from the Department of Health, Taiwan. Multiple logistic regression models were used to estimate the odds ratios (OR) of birth outcomes and deaths, controlling for infant sex, maternal age, and paternal education. A total of 5,702 children were born to male workers during the period 1980-1994. There were increased risks of deaths with congenital anomalies (adjusted OR, 3.26; and 95% confidence interval [CI], 1.12-9.44) and heart anomalies (OR, 4.15; 95% CI, 1.08-15.95) in the offspring of male workers who were employed during the two months before conception. We found evidence of a possible link between paternal preconception exposure of semiconductor manufacturing and an increased risk of congenital anomalies, especially of the heart. The possible etiological basis needs to be corroborated in further research.

Health risk in the offspring of female semiconductor workers.

BACKGROUND: There are no published studies focusing on adverse birth outcomes or infant mortality in the semiconductor industry. AIM: To investigate whether female workers have higher risks of any adverse birth outcome or death from congenital malformation. METHODS: A total of 27,610 female workers had been employed in eight semiconductor companies in Taiwan between 1980 and 2000. Using the national birth registry, their live born children were identified, and then any deaths under 5 years of age with or without congenital malformations were identified by linking with the national death registry. Periconceptional exposure was defined as the mother having been employed in the semiconductor industry 3 months before and 3 months after conception of the live born infants. RESULTS: A total of 24,223 live births were included. No significant association between adverse birth outcomes or death with congenital malformation and maternal employment in semiconductor industry was found either in the period of 1980-94 or 1995-2000. CONCLUSIONS: There is no convincing evidence that female workers employed during the periconceptional period in the semiconductor industry had higher risks of having adverse birth outcomes or death due to congenital malformations. However, prospective research is warranted to confirm these findings.

Estimation of the financial burden to the National Health Insurance for patients with major cancers in Taiwan.

BACKGROUND/PURPOSE: Almost all countries that have national health insurance schemes face financial challenges. A better understanding of the financial burden that cancer places on Taiwan's National Health Insurance (NHI) is important for helping policy makers to plan under scarce healthcare resources. This study attempts to estimate lifetime health expenditure for patients with 17 types of major cancers. METHODS: A total of 425,294 patients, each of whom was registered in Taiwan during 1990 to 2001 as having one of 17 major types of cancers, were included. All of them were followed until the end of 2004. Monte Carlo simulation was used to extrapolate survival for up to 600 months to derive the life expectancy or lifetime survival function after diagnosis for different cancers. The average annual health expenditure per case for each cancer type was calculated by using data from the NHI's reimbursement database. The lifetime health expenditure per case was estimated by multiplying the monthly survival probability by the average monthly health expenditure, adjusting for the annual discount rate and the medical care inflation rate. By incorporating the number of annual incidence cases, the total lifetime health expenditure can also be estimated. RESULTS: Of the 17 cancers studied, it was found that leukemia had the highest average annual health expenditure per case (207,000 TWD) as well as the highest lifetime health expenditure per case (2,404,000 TWD, without discounting adjustment). Breast cancer had the highest total lifetime health expenditure (5046 million TWD) because of the longer life expectancy and chronic morbidity. Furthermore, colorectal cancer had the second highest total lifetime health expenditure (4995 million TWD) due to its high incidence. CONCLUSION: The proposed method is a feasible way of estimating lifetime health expenditure for cancer patients even under high censoring rates. This would be helpful for cost-effectiveness assessment of cancer prevention programs and for policy planning.

Clustering of malignant pleural mesothelioma in asbestos factories: a subgroup analysis in a 29-year follow-up study to identify high-risk industries in Taiwan.

OBJECTIVE: Exposure to asbestos is the major cause for malignant pleural mesothelioma (MPM), but the causal link of individual cases is difficult to establish for lack of exposure information and long disease latency. METHODS: We established a retrospective cohort of workers employed in asbestos industries during the period of 1950-1989 and the occurrence of MPM during the period of 1980-2009 was examined with the Taiwan Cancer Registry. Estimated rate ratios (eRRs) were computed for each factory where any case of MPM was diagnosed by assuming Poisson distribution with a minimal latency of 20 years. RESULTS: A total of 18 MPM (17 males, 1 female) in eight factories were found. The incidence rate of MPM for the eight factories was 18.0 per million, ranging from 6.2 per million (military factory) to 268.2 per million (asbestos cement). We observed significantly increased risks for MPM in asbestos cement, thermal insulation and shipbuilding industries, with eRR (genders combined) of 113.6, 87.5 and 15.8, respectively. The sensitivity analyses considering latency showed similar findings in latency ≥30 years, and the shipbuilding industry presented a significant eRR given a latency ≥40 years. The gender-specific eRR showed similar results in men, but high eRR of 729.6 was observed in an asbestos cement factory where a female MPM was diagnosed. CONCLUSIONS: This nationwide study in Taiwan comprehensively shows that different asbestos manufacturing processes, including asbestos cement, thermal insulation and shipbuilding industries, were at significantly increased risks for MPM. We recommend to establish a medical screening programme for workers previously exposed to asbestos to identify MPM and other asbestos-related diseases at an earlier stage.

Cost-effectiveness of highly active antiretroviral therapy for HIV infection in Taiwan.

BACKGROUND/PURPOSE: Since the late 1980s, the Taiwanese government has provided all HIV-infected citizens with free access to antiretroviral therapy. Recently, there is controversy as to whether or not free access to expensive highly active antiretroviral therapy (HAART) should be continued for HIV-infected patients. This study aimed to evaluate the cost-effectiveness of HAART therapy. METHODS: HAART-associated improvement in survival was obtained by analyzing the follow-up data of all HIV-positive patients identified during April 1984 to March 1997 (pre-HAART era) and May 1997 to April 2003 (HAART era) in Taiwan. Data on quality of life in HIV-positive patients was obtained from a cross-sectional survey of 224 patients using standard gamble method and World Health Organization Quality of Life-BREF instrument. Information regarding the cost of HAART was obtained from the National Health Insurance (NHI). RESULTS: In 2000, the average annual NHI expenditure on HAART per HIV-positive patient receiving HAART was NT$210,018 (US$6177, at an exchange rate of 34.0 NT$/US$). In the AIDS group, the cost was NT$176,441 (US$5189) per life year gained and NT$241,700 (US$7109) per quality-adjusted life year gained. For non-AIDS patients, the corresponding costs were NT$226,156 (US$6652) and NT$332,582 (US$9782), respectively. These estimates have not yet included the additional cost savings from HAART-associated reduction in hospitalization and use of antimicrobial agents for opportunistic infections, and the additional life years gained from the reduction in HIV transmission under the universal availability of HAART. CONCLUSION: HAART for HIV infection is cost-effective, especially when the societal and epidemiologic factors are considered. We recommend that the policy of providing free HAART to all HIV-infected citizens be continued.