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.

The association between economic indicators and the incidence of tetraplegia from traumatic spinal cord injury in Taiwan.

BACKGROUND: Economic performance may affect public health parameters. This study aimed to determine the time trend of incidence of traumatic spinal cord injury (SCI) and its association with income, presented by GDP (gross domestic product) per capita. METHODS: This study was a retrospective observational study in Taiwan. Newly diagnosed SCI patients with moderate to severe disability from 2002 to 2015 were identified from the reimbursement database of the National Health Insurance (NHI) system (1998-2015). CIR16-99 (cumulative incidence rate, aged 16-99 years, per 103 person-years) and CIR16-59 (aged 16-59 years) of SCI from 2002 to 2015 were measured. RESULTS: There were 5048 newly diagnosed SCI patients during the study period. After controlling the factors of sex, urbanization level, literacy, income inequality, and global financial crisis (mixed effects models), the CIR16-99 of SCI, traumatic SCI, motor vehicle (MV)-related SCI, fall-related SCI, tetraplegia, traumatic tetraplegia, MV-related tetraplegia, and fall-related tetraplegia were inversely associated with GDP per capita; the ß coefficients ranged from - 4.85 (95% confidence interval - 7.09 to - 2.6) for total SCI to - 0.8 (- 1.3 to - 0.29) for fall-related tetraplegia. We restricted our comparison to Taipei City and the 4 lowest densely populated counties, which also corroborated with the above results. The income elasticity analysis revealed when GDP per capita increased by 1%, the total SCI decreased by 1.39‰; which was also associated with a decrease of 1.34‰, 1.55‰, 1.36‰, 1.46‰, 1.54‰, 1.54‰, and 1.62‰ for traumatic SCI, MV-related SCI, fall-related SCI, tetraplegia, traumatic tetraplegia, MV-related tetraplegia, and fall-related tetraplegia respectively. The ß coefficients show that the compared areas of urbanization level were also inversely correlated with CIR16-59 in the SCI population. CONCLUSIONS: We conclude that the incidence of tetraplegia of traumatic SCI in Taiwan decreases with good economic performance, which may be resulted from the provision of public goods and services, possibly through improvements in the infrastructure of transportation and construction.

Savings of loss-of-life expectancy and lifetime medical costs from prevention of spinal cord injuries: analysis of nationwide data followed for 17 years.

BACKGROUND: The objectives of this research were to determine the savings of loss-of-life expectancy (LE) and lifetime medical costs (LMC) from prevention of spinal cord injuries (SCI) in Taiwan. METHODS: From the claims database of Taiwan National Health Insurance, we identified 6164 adult patients with newly diagnosed SCI with permanent functional disability from 2000 to 2015 and followed them until the end of 2016. We estimated survival function through the Kaplan-Meier method and extrapolated it to lifetime. RESULTS: For the SCI cohort, the LE and loss-of-LE were 17.6 and 13.3 years, respectively, while those for SCI with coding of external causes (E-code) were 18.1 and 13.0 years, respectively. For the SCI cohort with E-code, the loss-of-LE of motor vehicle (MV)-related SCI was significantly higher than that of fall-related SCI. In young and middle-aged patients with SCI with E-code, the loss-of-LE of MV-related paraplegia was significantly higher than that of MV-related quadriplegia and fall-related SCI. With a 3% discount rate, the LMC for patients with SCI after diagnosis were US$82 772, while those for patients with SCI with E-code were US$81 473. The LMC and the cost per year for those living with quadriplegia were significantly higher than those for paraplegia in all age groups, possibly related to the higher frequencies of stroke, chronic lung disease and dementia. CONCLUSIONS: We conclude that quadriplegia has a higher impact on medical costs than paraplegia, and MV-related SCI has a higher impact on loss-of-LE than fall-related SCI. We recommend comprehensive SCI prevention be established, including infrastructures of construction and transportation.

Alcohol and tea consumption are associated with asymptomatic erosive esophagitis in Taiwanese men.

OBJECTIVE: Asymptomatic erosive esophagitis (AEE) is commonly found in men, and might be a risk factor of developing esophageal adenocarcinoma. We aimed to determine if specific dietary habits increase the risk of AEE in asymptomatic Taiwanese men. METHODS: We recruited male adults undergoing upper gastrointestinal endoscopy for health check. We excluded subjects with reflux symptoms, or taking anti-reflux medications or drugs that potentially impair lower esophageal sphincter function or cause mucosal injury. The frequency of consuming reflux-provoking diets including alcohol, tea, coffee, tomato/citric juice, chocolate, sweet food, and spicy food was assessed. The erosive esophagitis was diagnosed based on the Los Angeles Classification after endoscopy. Frequent consumption of a specific diet was defined as ≥4 days/week of consuming that diet. RESULTS: A total of 1256 participants were recruited. After excluding 424 ineligible subjects, AEE was identified in 180 (22%) among 832 asymptomatic subjects. The risk of AEE increased with the number of days per week of consuming alcohol or tea: nondrinkers (19%, 17%), occasional drinkers (<1 day/week; 19%, 15%), regular drinkers (1-3 days/week; 26%, 21%), frequent drinkers (4-6 days/week; 32%, 22%), and daily drinkers (42%, 28%), respectively (trend test P < 0.001 for both). Multivariate analysis showed that hiatus hernia (adjusted odds ratio (aOR) 5.0, 95% confidence interval (CI) 2.6-9.6), drinking alcohol ≥4 days/week (aOR 2.3, 95% CI 1.3-4.0), and drinking tea ≥4 days/week (aOR 1.6, 95% CI 1.1-2.3) are independent risk factors of AEE. The risk of AEE was 3.8 times greater for those drinking both alcohol and tea ≥4 days/week than the non-drinkers. CONCLUSIONS: Frequent alcohol and tea consumption increased the risk of AEE in Taiwanese men.

Estimation of life expectancy, loss-of-life expectancy, and lifetime healthcare expenditures for schizophrenia in Taiwan.

By employing a novel semi-parametric extrapolation method, the life expectancies after the first hospitalization for schizophrenia and the associated lifetime healthcare expenditures were both estimated. Based on the linkage between the National Health Insurance Research Database and the National Mortality Registry of Taiwan, we have established a schizophrenic cohort for 2000-2010 and followed up to 2011. Survival function was estimated through Kaplan-Meier's method and extrapolated throughout life. We applied a simple linear regression to the logit-transformed survival ratio between the schizophrenic cohort and the sex-, age-matched referents via Monte Carlo simulation from the national life table. The monthly survival probability was multiplied by the average healthcare expenditures and summed throughout life to estimate the lifelong cost reimbursed by the National Health Insurance. The results showed that patients diagnosed at age 20-29 had the highest expected years of life lost (EYLL), 15 and 9years, in men and women, respectively, with corresponding lifetime healthcare expenditures of USD 48,000 and 53,000. Males generally had higher health cost per life-year than their female counterparts across their lifespan. We applied the same method to the first 6years of the cohort and extrapolated to 12years, which showed that the relative biases for different age strata were less than 5%. We thus concluded that the semi-parametric extrapolation method might provide a timely estimation of lifetime outcomes for health care planning of schizophrenia.

Chinese herbs containing aristolochic acid associated with renal failure and urothelial carcinoma: a review from epidemiologic observations to causal inference.

Herbal remedies containing aristolochic acid (AA) have been designated to be a strong carcinogen. This review summarizes major epidemiologic evidence to argue for the causal association between AA exposure and urothelial carcinoma as well as nephropathy. The exposure scenarios include the following: Belgian women taking slimming pills containing single material Guang Fang Ji, consumptions of mixtures of Chinese herbal products in the general population and patients with chronic renal failure in Taiwan, occupational exposure in Chinese herbalists, and food contamination in farming villages in valleys of the Danube River. Such an association is corroborated by detecting specific DNA adducts in the tumor tissue removed from affected patients. Preventive actions of banning such use and education to the healthcare professionals and public are necessary for the safety of herbal remedies.

Increased risk of urinary tract cancer in ESRD patients associated with usage of Chinese herbal products suspected of containing aristolochic acid.

INTRODUCTION: Both end-stage renal disease (ESRD) and urothelial cancer (UC) are associated with the consumption of Chinese herbal products containing aristolochic acid (AA) by the general population. The objective of this study was to determine the risk of UC associated with AA-related Chinese herbal products among ESRD patients. METHODS: We conducted a cohort study using the National Health Insurance reimbursement database to enroll all ESRD patients in Taiwan from 1998-2002. Cox regression models were constructed and hazard ratios and confidence intervals were estimated after controlling for potential confounders, including age, sex, residence in region with endemic black foot disease, urinary tract infection, and use of non-steroidal anti-inflammatory drugs and acetaminophen. RESULTS: A total of 38,995 ESRD patients were included in the final analysis, and 320 patients developed UC after ESRD. Having been prescribed Mu Tong that was adulterated with Guan Mu Tong (Aristolochia manshuriensis) before 2004, or an estimated consumption of more than 1-100 mg of aristolochic acid, were both associated with an increased risk of UC in the multivariable analyses. Analgesic consumption of more than 150 pills was also associated with an increased risk of UC, although there was little correlation between the two risk factors. CONCLUSION: Consumption of aristolochic acid-related Chinese herbal products was associated with an increased risk of developing UC in ESRD patients. Regular follow-up screening for UC in ESRD patients who have consumed Chinese herbal products is thus necessary.

Increased upper and lower tract urothelial carcinoma in patients with end-stage renal disease: a nationwide cohort study in Taiwan during 1997-2008.

BACKGROUND: Urothelial cancer (UC) is the leading cancer of patients with end-stage renal disease (ESRD) in Taiwan. The aims of this study were to explore the time trends of UC incidences and propose possible etiologic factors. METHODS: Abstracting from the National Health Insurance Research Database (NHIRD), there were 90,477 newly diagnosed cases of ESRD between 1997 and 2008 covering the patients aged 40-85. Among them, 2,708 had developed UC after diagnosis of ESRD. The CIR40-85 (cumulative incidence rate) of upper tract UC (UTUC) and lower tract UC (LTUC) were calculated for ESRD patients and general population, as well as SIR40-85 (standardized incidence ratio) for comparison. RESULTS: Female ESRD patients were found to have 9-18 times of elevated risks of UC, while those of males were increased up to 4-14 times. The time trends of CIR40-84 and SIR40-84 of UTUC in females appear to decline after calendar year 2000. These trends may be related to AA associated herbal products after 1998. CONCLUSIONS: Patients with ESRD are at increased risks for both LTUC and UTUC in Taiwan. We hypothesize that the time trends associate with the consumption of aristolochic acid in Chinese herbal products (female predominant).

Increasing incidence and lifetime risk of inflammatory bowel disease in Taiwan: a nationwide study in a low-endemic area 1998-2010.

BACKGROUND: The incidence of inflammatory bowel disease is increasing worldwide, but data of epidemiological trends from low-endemic area are limited. As one of the low-endemic countries, we describe the trends of this disease in Taiwan over time. METHODS: This study was based on data obtained from the Catastrophic Illnesses Registration in the National Health Insurance Research Database, which covers more than 98% of the people in Taiwan. Every certificate of catastrophic illness must be approved by 2 expert gastroenterologists. Thirteen years (1998-2010) of data were analyzed for the trends of Crohn's disease (CD) and ulcerative colitis (UC). RESULTS: A total of 2915 incident cases (1818 men and 1097 women) were identified, including 2357 cases of UC and 558 cases of CD. The mean annual incidence rates were 0.80 for UC and 0.19 for CD per 100,000 inhabitants, with lifetime risks for those 20 to 79 years of age of 0.066% and 0.013%, respectively. The mean annual prevalence was 4.59 for UC and 1.05 for CD per 100,000 inhabitants. Poisson regression showed significantly increased trends during the observation period for both diseases, with a men/women ratio of 1.50 in UC and 2.14 in CD (P < 0.01). The mean age of individuals at diagnosis was higher for UC as compared with CD (44.7 versus 37.9, P < 0.001). CONCLUSIONS: Inflammatory bowel diseases are still relatively uncommon in Taiwan, but the incidence and prevalence rates are increasing.

Observational studies on evaluating the safety and adverse effects of traditional chinese medicine.

Background. This study aims to share our experiences when carrying out observational studies of traditional Chinese medicine (TCM). Methods. We have proactively monitored the safety profiles of Duhuo Jisheng Tang (DJT), Suan Zao Ren Tang (SZRT), and TMN-1. A list of adverse events (AEs), complete blood counts, and liver and kidney function tests were obtained from the participants during their scheduled hospital visits. Retrospective observational studies were conducted based on the reimbursement database of the National Health Insurance system, Taiwan, to explore the relationship between the use of TCM that have been adulterated by aristolochic acid and the risk from both nephrotoxins and carcinogens. Results. A total of 221, 287, and 203 AEs were detected after SZRT, DJT, and TMN-1 had been taken, respectively. Dizziness, headache, stomach ache, and diarrhea were judged to be probably related to SZRT treatment. Retrospective observational studies found an association between the consumption of aristolochic acid-containing Chinese formulae such as Mu Tong and an increased risk of CKD, ESRD, and urinary tract cancer. Conclusion. Prospective and retrospective observational studies seem to have specific advantages when investigating the safety and adverse effects of TCM therapies, as well as possibly other alternative/complementary therapies.

The association between asymmetric hip mobility and neck pain in young adults.

OBJECTIVE: The objective of this cross-sectional observational study was to determine whether asymmetric hip mobility was associated with neck pain in young adults. METHODS: Three hundred twenty-seven freshmen students were recruited from an urban university and underwent the Patrick's flexion, abduction, external rotation, extension (FABERE) test for comparison of the functional mobility of bilateral hip joints during the health examination. A logistic regression model was constructed to determine whether the asymmetry measured by the Patrick's FABERE test was associated with neck pain after adjusting for factors of sex and exercise habits. RESULTS: The frequency of asymmetric results of the Patrick's FABERE test among the students who reported neck pain was significantly higher than that of those without neck pain (54.2% vs 26.5%; P < .001). After adjusting for the above confounders, the odds ratio of asymmetric results of a Patrick's FABERE test was 2.99 (95% confidence interval, 1.57-5.72; P < .001). CONCLUSIONS: Imbalanced mobility of the hip joints might be associated with an increased incidence of neck pain.

Concurrent Use of Conventional Drugs with Chinese Herbal Products in Taiwan: A Population-based Study.

The increased use of Chinese herbal products (CHPs) worldwide has raised the concern of herb-drug interactions. The aim of this study was to determine the prevalence and utilization patterns of concurrent use of conventional drugs and CHPs in Taiwan. The usage and frequency of services in the co-prescription of a CHP and a conventional drug were evaluated. Subjects were recruited from a simple random sample of 1,000,000 subjects from over 22 million beneficiaries of the National Health Insurance in 2007. The logistic regression method was employed to estimate the odds ratios (ORs) for the co-prescription of a CHP and a conventional drug (CH + D) and a conventional drug alone (D-alone). The prevalence of the CH + D was 14.1%. Females, regular salary earners, and elderly (65 years and above) were more likely to consume a CHP and a conventional drug concurrently. Painkillers, especially acetaminophen, and anti-cough medicines were the top two conventional drugs that were most frequently co-prescribed with a CHP. Anti-cough medication is the most common conventional drug co-prescribed with CHP, after painkillers. We recommend that safety issues be investigated in future research and integrating both healthcare technologies may be beneficial for the overall health and quality of life of patients.

Occupational exposure to herbs containing aristolochic acids increases the risk of urothelial carcinoma in Chinese herbalists.

PURPOSE: Aristolochic acid can cause urothelial carcinoma. Herbal remedies containing aristolochic acids were previously categorized as proven group 1 human carcinogens by the WHO cancer agency, the International Agency for Research on Cancer. However, the health effect on workers exposed to aristolochic acid is unclear. Fangchi, a representative herb containing aristolochic acid, is commonly used in the Chinese herbal medicine industry. We determined whether workers exposed to fangchi are at increased risk for urothelial carcinoma. MATERIALS AND METHODS: We designed a case-control study based in a national representative cohort of Chinese herbalists. This study analyzed 6,564 Chinese herbalists employed between 1985 and 1998. All incident cases of urothelial carcinoma that occurred between 1988 and 2001 were defined as the case group. Controls were selected from the baseline cohort in a randomized manner. A total of 24 cases and 140 controls were included in analysis. Information about fangchi exposure was obtained in a questionnaire survey administered in 2002. RESULTS: Processing, selling or dispensing herbs containing fangchi significantly increased the risk of urothelial carcinoma (HR 2.4, 95% CI 1.1-5.3, p = 0.03). This relationship was independent of cigarette smoking or potential arsenic exposure from drinking water from deep wells. CONCLUSIONS: Exposure to the Chinese herbal drug fangchi increases the risk of urothelial carcinoma in herbalists. Appropriate medical monitoring is warranted for workers who have similar exposure.

Prescription profile of Chinese herbal products containing coumestrol, genestein, and/or daidzein among female users: an analysis of national health insurance data in Taiwan between 1997 and 2007.

BACKGROUND: Some Chinese herbs contain several kinds of phytoestrogens, and these herbs are commonly prescribed in Taiwan. Phytoestrogens may influence the effects of estrogen in females, although their activities are weak. This study aims to identify the risk and analyze the prescription profile of commonly used phytoestrogenic herbs in Taiwan. METHODS: The study analyzed women who had been prescribed phytoestrogenic herbs including coumestrol, genistein and/or daidzein between 1997 and 2007 in a fixed cohort taken from all female beneficiaries from the National Health Insurance Research Database of Taiwan. The prescription frequencies, cumulated dosages, and primary indications were listed. RESULTS: A total of 462,861 women were included in the study, of whom ~47.0% had used phytoestrogenic herbs at least once during the study period. A total of 6,270,813 prescriptions were recorded, and more than 20% of these contained phytoestrogens. The most commonly prescribed herb and formula were Puerariae Radix and Ge gen tang (Pueraria Decoction), respectively. Most of the prescriptions were issued for diseases of the respiratory system, followed by symptoms, signs, and ill-defined conditions and diseases of the musculoskeletal system and connective tissue. CONCLUSION: This study shows that women who sought medical treatment from Chinese medicine doctors for relief of respiratory discomfort had a high possibility of exposure to phytoestrogenic herbs. Safety issues related to the female endocrine system should be a priority for future research.

Prescription pattern of chinese herbal products for breast cancer in taiwan: a population-based study.

Background. Chinese herbal products (CHPs) given as a therapy for symptom relief have gained widespread popularity among women with breast cancer. The aim of this study was to analyze the utilization of CHP among women with breast cancer in Taiwan. Methods. The usage, frequency of services, and CHP prescribed for breast cancer among women with breast cancer were evaluated, recruited from a randomly sampled cohort of 1,000,000 beneficiaries from the National Health Insurance Research Database. The logistic regression method was employed to estimate the odds ratios (ORs) for utilization of CHP. Results. 81.5 percent (N = 2, 236) of women with breast cancer utilized traditional Chinese medicine (TCM) and 18% of them sought TCM with the intent of treating their breast cancer. Jia-wei-xiao-yao-san (Augmented Rambling Powder) was the most frequently prescribed formula for treating breast cancer. Among the top 10 most frequently prescribed CHP for treating breast cancer, seven contained dang qui (Angelica sinensis-radix) and six contained ren shen (Panax ginseng-radix), which are reported to have potential beneficial synergistic effects on breast cancer cells. Conclusion. CHP containing dang qui (Angelica sinensis-radix) or ren shen (Panax ginseng-radix) are the most frequently prescribed for breast cancer and their effects should be taken into account by healthcare providers.

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.

Outcomes of prolonged mechanic ventilation: a discrimination model based on longitudinal health insurance and death certificate data.

BACKGROUND: This study investigated prognosis among patients under prolonged mechanical ventilation (PMV) through exploring the following issues: (1) post-PMV survival rates, (2) factors associated with survival after PMV, and (3) the number of days alive free of hospital stays requiring mechanical ventilation (MV) care after PMV. METHODS: This is a retrospective cohort study based on secondary analysis of prospectively collected data in the national health insurance system and governmental data on death registry in Taiwan. It used data for a nationally representative sample of 25,482 patients becoming under PMV (> = 21 days) during 1998-2003. We calculated survival rates for the 4 years after PMV, and adopted logistic regression to construct prediction models for 3-month, 6-month, 1-year, and 2-year survival, with data of 1998-2002 for model estimation and the 2003 data for examination of model performance. We estimated the number of days alive free of hospital stays requiring MV care in the immediate 4-year period after PMV, and contrasted patients who had low survival probability with all PMV patients. RESULTS: Among these patients, the 3-month survival rate was 51.4%, and the 1-year survival rate was 31.9%. Common health conditions with significant associations with poor survival included neoplasm, acute and unspecific renal failure, chronic renal failure, non-alcoholic liver disease, shock and septicaemia (odd ratio < 0.7, p < 0.05). During a 4-year follow-up period for patients of year 2003, the mean number of days free of hospital stays requiring MV was 66.0 in those with a predicted 6-month survival rate < 10%, and 111.3 in those with a predicted 2-year survival rate < 10%. In contrast, the mean number of days was 256.9 in the whole sample of patients in 2003. CONCLUSIONS: Neoplasm, acute and unspecific renal failure, shock, chronic renal failure, septicemia, and non-alcoholic liver disease are significantly associated with lower survival among PMV patients. Patients with anticipated death in a near future tend to spend most of the rest of their life staying in hospital using MV services. This calls for further research into assessing PMV care need among patients at different prognosis stages of diseases listed above.

Increased risk for invasive breast cancer associated with hormonal therapy: a nation-wide random sample of 65,723 women followed from 1997 to 2008.

BACKGROUND: Hormonal therapy (HT) either estrogen alone (E-alone) or estrogen plus progesterone (E+P) appears to increase the risk for breast cancer in Western countries. However, limited information is available on the association between HT and breast cancer in Asian women characterized mainly by dietary phytoestrogens intake and low prevalence of contraceptive pills prescription. METHODOLOGY: A total of 65,723 women (20-79 years of age) without cancer or the use of Chinese herbal products were recruited from a nation-wide one-million representative sample of the National Health Insurance of Taiwan and followed from 1997 to 2008. Seven hundred and eighty incidents of invasive breast cancer were diagnosed. Using a reference group that comprised 40,052 women who had never received a hormone prescription, Cox proportional hazard models were constructed to determine the hazard ratios for receiving different types of HT and the occurrence of breast cancer. CONCLUSIONS: 5,156 (20%) women ever used E+P, 2,798 (10.8%) ever used E-alone, and 17,717 (69%) ever used other preparation types. The Cox model revealed adjusted hazard ratios (HRs) of 2.05 (95% CI 1.37-3.07) for current users of E-alone and 8.65 (95% CI 5.45-13.70) for current users of E+P. Using women who had ceased to take hormonal medication for 6 years or more as the reference group, the adjusted HRs were significantly elevated and greater than current users and women who had discontinued hormonal medication for less than 6 years. Current users of either E-alone or E+P have an increased risk for invasive breast cancer in Taiwan, and precautions should be taken when such agents are prescribed.

Increased risks of upper tract urothelial carcinoma in male and female chinese herbalists.

BACKGROUND/PURPOSE: It has been shown that herbs that contain aristolochic acid induce urological cancer. Chinese herbalists have easy access to such herbs. Our previous mortality study has shown a significantly increased risk of urological cancer in female but not male herbalists. To re-examine this risk in male herbalists, the incidence of urological cancer was analyzed. METHODS: We enrolled all 6550 Chinese herbalists in Taiwan registered during 1985-2000, and we retrospectively followed the development of cancer until 2001 by analysis of data collected from the Taiwan Cancer Registry. Standardized incidence ratios (SIRs) were calculated for urological cancers in herbalists and compared with those for the general population in Taiwan. RESULTS: There were 30 newly diagnosed cases of urological cancer and most of them were transitional cell carcinoma (93.1%). The mean age at diagnosis for urothelial carcinoma was 51.6 years, and 51.9% were in the upper urinary tract. After adjustment for age and sex, the SIR for all urological cancers was 3.51 [(95% confidence interval (CI): 2.37-5.01]. When stratified by location, the SIRs for kidney and upper urinary tract cancers and bladder cancer were 4.24 (95% CI: 2.47-6.80) and 2.86 (95% CI: 1.52-4.89), respectively. When analyzed by sex, the SIRs for all urological cancers, kidney and upper urinary tract cancers, and bladder cancer were also significantly increased in male herbalists. CONCLUSION: The significant risk of urothelial carcinoma noted in male herbalists increases our suspicion that this is an occupational disease that renders regular health assessment of herbalists an urgent necessity.