Hui-Fen Chiu

Statin Use and the Risk of Liver Cancer: A Population-Based Case - Control Study

OBJECTIVES:Experimental studies have shown that statins have potential protective effects against cancer. The aim of this study was to investigate whether the use of statins was associated with liver cancer risk.METHODS:We conducted a population-based case–control study in Taiwan. Data were retrospectively collected from the Taiwan National Health Insurance Research Database. Cases consisted of all patients who were aged ≥50 years and had a first-time diagnosis of liver cancer for the period between 2005 and 2008. Controls were pair matched to cases by age, sex, and index date. Adjusted odds ratios (ORs) and 95% CIs (95% confidence intervals) were estimated using multiple logistic regression.RESULTS:We examined 1,166 liver cancer cases and 1,166 controls. Compared with the group with no use of statins, the adjusted ORs were 0.62 (95% CI=0.42–0.91) for the group having been prescribed statins below 215.4 defined daily dose (DDD) and 0.63 (95% CI=0.37–1.06) for the group with cumulative statin use ≥215.4 DDD. The ORs for the group with cumulative statin use ≥215.4 DDD were not statistically significant, but this may be due to the relatively small number of subjects.CONCLUSIONS:The results of this study suggest that statins may reduce the risk of liver cancer.

DOES ARSENIC EXPOSURE INCREASE THE RISK FOR LIVER CANCER? 1

Arsenic has been well documented as the major risk factor for development of blackfoot disease (BFD), a unique peripheral vascular disease that was once endemic to the southwestern coast of Taiwan, where residents imbibed artesian well water containing high concentrations of arsenic for more than 50yr. Long-term arsenic exposure has also been reported to be associated with increased incidence of liver cancer in a dose-responsive manner. A tap-water supply system was implemented in the early 1960s in the BFD endemic areas. Artesian well water was no longer used for drinking and cooking after the mid-1970s. The objective of this study was to examine whether liver cancer mortality rates were altered after the consumption of high-arsenic artesian well water ceased and, if so, when the reduction occurred. Standardized mortality ratios (SMRs) for liver cancer were calculated for the BFD endemic area for the years 1971–2000. Cumulative-sum techniques were used to detect the occurrence of changes in the SMRs. The study results show that mortality from liver cancer in females declined starting 9yr after the cessation of consumption of high-arsenic artesian well water. However, data show fluctuations in male liver cancer mortality rates. Based on the reversibility criterion, the association between arsenic exposure and liver cancer mortality is likely to be causal for females but not in males.

Consequences of Exposure to Asian Dust Storm Events on Daily Pneumonia Hospital Admissions in Taipei, Taiwan

In spring, windblown dust storms originating in the deserts of Mongolia and China travel to Taipei city. These occurrences are known as Asian dust storm (ADS) events. The objective of this study was to assess the possible associations of constituents of ADS with hospital pneumonia admissions of residents in Taipei, Taiwan, during the period 1996–2001. Fifty-four dust storm episodes were identified and were classified as index days. Daily pneumonia admissions on the index days were compared with admissions on comparison days. Two comparison days for each index day, 7 d before the index days and 7 d after the index days, were selected. The study results indicated a statistically significant association between ADS events and daily pneumonia admissions 1 d after the event. It is worthwhile to pay more attention to ADS events and health in the future based on the findings in this investigation.

Increased risk of preterm delivery in areas with air pollution from a petroleum refinery plant in Taiwan.

The petrochemical and petroleum industries are among the main sources of industrial air pollution in Taiwan. Data in this study concern outdoor air pollution and the health of individuals living in communities in close proximity to a petroleum refinery plant. The prevalence of delivery of preterm birth infants was significantly higher in mothers living in a petroleum refinery area compared to controls in Taiwan. After controlling for several possible confounders (including maternal age, season, marital status, maternal education, and infant sex), the adjusted odds ratio was 1.41 (95% CI = 1.08-1.82) for delivery of preterm infants in the polluted region. Data support the view that air pollution can affect the outcome of pregnancy.

Outdoor air pollution and female lung cancer in Taiwan.

To investigate the relationship between air pollution and female lung cancer, the authors conducted a matched case-control study using female deaths that occurred in Taiwan from 1994 through 2003. Data on all eligible female lung cancer deaths were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. The control group consisted of women who died from causes other than cancer or diseases associated with respiratory problems. The controls were pair matched to the cases by sex, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. A municipality-based aggregate index of long-term exposure to air pollution was created by dividing the annual average of the measured values for each pollutant by the National Ambient Air Quality Standard for that pollutant. The ratios for each pollutant were scaled to a 100-point scale and then averaged together to generate an index value representing the net burden of these pollutants, with each weighted equally. The subjects were divided into tertiles according to the levels of the index just described. Women who lived in the group of municipalities with highest levels of air pollution exposure index were at a statistically significant increased lung cancer risk compared to the group living in municipalities with the lowest air pollution exposure index after controlling for possible confounders (OR = 1.28, 95% CI = 1.02–1.61). The findings of this study warrant further investigation of the role of air pollutants in the etiology of lung cancer.

Nitrate in Drinking Water and Risk of Death from Bladder Cancer: An Ecological Case-Control Study in Taiwan

The relationship between nitrate levels in drinking water and bladder cancer development is controversial. A matched cancer case-control with nitrate ecology study was used to investigate the association between bladder cancer mortality occurrence and nitrate exposure from Taiwan drinking water. All bladder cancer deaths of Taiwan residents from 1999 through 2003 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair-matched to the cases by gender, year of birth,and year of death. Each matched control was selected randomly from the set of possible controls for each cancer case. Data on nitrate-nitrogen (NO3-N) levels in drinking water throughout Taiwan were collected from Taiwan Water Supply Corporation (TWSC). The municipality of residence for cancer cases and controls was assumed to be the source of the subjects nitrate exposure via drinking water. The adjusted odds ratios for bladder cancer death for those with high nitrate levels in their drinking water were 1.76 (1.28–2.42) and 1.96 (1.41–2.72) as compared to the lowest tertile. The results of the present study show that there was a significant positive relationship between the levels of nitrate in drinking water and risk of death from bladder cancer.

Childhood Leukemia and Traffic Air Pollution in Taiwan: Petrol Station Density as an Indicator

To investigate the relationship between traffic air pollution exposure and development of childhood leukemia (14 yr of age or younger), a matched case-control study was conducted using childhood deaths that occurred in Taiwan from 1996 through 2006. Data on all eligible childhood leukemia deaths were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. The control group consisted of children who died from causes other than neoplasms or diseases that were not associated with respiratory complications. The controls were pair matched to the cancer cases by gender, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. Data on the number of petrol stations in study municipalities were collected from the two major petroleum supply companies, Chinese Petroleum Corporation (CPC) and Formosa Petrochemical Corporation (FPCC). The petrol station density (per square kilometer) (PSD) for study municipalities was used as an indicator of a subjects exposure to benzene and other hydrocarbons present in evaporative losses of petrol or to air emissions from motor vehicles. The subjects were divided into tertiles according to PSD in their residential municipality. The results showed that there was a significant exposure-response relationship between PSD and the risk of leukemia development in young children after controlling for possible confounders. The findings of this study warrant further investigation of the role of traffic air pollution exposure in the etiology of childhood leukemia.

CALCIUM AND MAGNESIUM IN DRINKING WATER AND RISK OF DEATH FROM PROSTATE CANCER

The possible association between the increased risk of prostate cancer and the levels of calcium and magnesium in drinking water from municipal supplies was investigated in a matched cancer case-control study in Taiwan. All eligible prostate-cancer deaths (682 cases) of Taiwan residents from 1987 through 1993 were compared with deaths from other causes (682 controls). The levels of calcium and magnesium in the drinking water of these residents were also determined. Data on calcium and magnesium levels in drinking water throughout Taiwan were obtained from the Taiwan Water Supply Corporation (TWSC). The control group consisted of people who died from other causes, and the controls were pair-matched to the cases by year of birth and death. The adjusted odds ratios for prostate cancer death for those with higher magnesium levels in their drinking water, as compared to the lowest tertile, were 0.73 (95% CI = 0.51-1.03) and 0.64 (95% CI = 0.43-0.96), respectively. The adjusted odd ratios for the relationship between calcium levels in drinking water and prostate cancer were not statistically significant. The results of the present study show that there may be a significant protective effect of magnesium intake from drinking water and other dietary sources against the risk of prostate cancer development.The possible association between the increased risk of prostate cancer and the levels of calcium and magnesium in drinking water from municipal supplies was investigated in a matched cancer case-control study in Taiwan. All eligible prostate-cancer deaths (682 cases) of Taiwan residents from 1987 through 1993 were compared with deaths from other causes (682 controls). The levels of calcium and magnesium in the drinking water of these residents were also determined. Data on calcium and magnesium levels in drinking water throughout Taiwan were obtained from the Taiwan Water Supply Corporation (TWSC). The control group consisted of people who died from other causes, and the controls were pair-matched to the cases by year of birth and death. The adjusted odds ratios for prostate cancer death for those with higher magnesium levels in their drinking water, as compared to the lowest tertile, were 0.73 (95% CI = 0.51?1.03) and 0.64 (95% CI = 0.43?0.96), respectively. The adjusted odd ratios for the relationship between calcium levels in drinking water and prostate cancer were not statistically significant. The results of the present study show that there may be a significant protective effect of magnesium intake from drinking water and other dietary sources against the risk of prostate cancer development.

Calcium and magnesium in drinking water and risk of death from colon cancer

The possible association between the risk of colon cancer and the levels of calcium and magnesium in drinking water from municipal supplies was investigated in a matched case‐control study in Taiwan. All eligible colon cancer deaths (1714 cases) of Taiwan residents from 1989 through 1993 were compared with deaths from other causes (1714 controls), and the levels of calcium and magnesium in drinking water of these residents were determined. Data on calcium and magnesium levels in drinking water throughout Taiwan were obtained from the Taiwan Water Supply Corporation. The control group consisted of people who died from other causes and the controls were pair‐matched to the cases by sex, year‐of‐birth, and year‐of‐death. The adjusted odd ratios (95% confidence interval) were 0.79 (0.64–0.98) for the group with water calcium levels between 24.4 and 42.3 mg/liter and 0.58 (0.47–0.73) for the group with calcium levels of 42.4 mg/liter or more. The adjusted odd ratios were not statistically significant for the relationship between magnesium levels in drinking water and colon cancer. The results of the present study show that there is a significant protective effect of calcium intake from drinking water against colon cancer

Calcium and magnesium in drinking water and the risk of death from breast cancer.

The relationship between mortality from breast cancer and the levels of calcium and magnesium in drinking water was examined using an ecological design. The study area consisted of 252 municipalities in Taiwan. Data on the levels of calcium and magnesium in drinking water were collected from the Taiwan Water Supply Corporation (TWSC). The age-standardized mortality rate (ASR) for breast cancer (1982?1991) was compared among municipalities with different levels of magnesium and calcium in drinking water. Weighted multivariate regression analysis was used, and after adjusting for fertility rates and urbanization, there was a significant inverse relationship between the levels of calcium and magnesium in drinking water and risk of death from breast cancer.The relationship between mortality from breast cancer and the levels of calcium and magnesium in drinking water was examined using an ecological design. The study area consisted of 2.52 municipalities in Taiwan. Data on the levels of calcium and magnesium in drinking water were collected from the Taiwan Water Supply Corporation (TWSC). The age-standardized mortality rate (ASR) for breast cancer ( 1982-1991) was compared among municipalities with different levels of magnesium and calcium in drinking water. Weighted multivariate regression analysis was used, and after adjusting for fertility rates and urbanization, there was a significant inverse relationship between the levels of calcium and magnesium in drinking water and risk of death from breast cancer.The relationship between mortality from breast cancer and the levels of calcium and magnesium in drinking water was examined using an ecological design. The study area consisted of 252 municipalities in Taiwan. Data on the levels of calcium and magnesium in drinking water were collected from the Taiwan Water Supply Corporation (TWSC). The age-standardized mortality rate (ASR) for breast cancer (1982?1991) was compared among municipalities with different levels of magnesium and calcium in drinking water. Weighted multivariate regression analysis was used, and after adjusting for fertility rates and urbanization, there was a significant inverse relationship between the levels of calcium and magnesium in drinking water and risk of death from breast cancer.