N-nitroso compounds (NOC) formed endogenously after nitrate/nitrite ingestion and disinfection by-products (DBPs) are suspected colorectal carcinogens, but epidemiologic evidence of these ...associations is limited.
We investigated the relationship between drinking water exposures and incident colorectal cancers in a cohort of postmenopausal women.
Using historical nitrate-nitrogen (NO3-N) measurements and estimates of total trihalomethanes (TTHM), the sum of 5 or 6 haloacetic acids (HAAs), and individual DBPs in public water supplies (PWS), we computed average exposures and years of exposure above one-half the U.S. maximum contaminant level (>1/2-MCL; >5 mg/L NO3-N and >40 μg/L TTHM). Nitrate/nitrite intakes from dietary sources were estimated using a food frequency questionnaire. We estimated hazard ratios (HR) and 95% confidence intervals (CI) from Cox regression models. We assessed NO3-N interactions with DBPs and with factors influencing endogenous NOC formation.
We identified 624 colon and 158 rectal cancers (1986–2010) among 15,910 women reporting PWS use >10 years. Ingestion of NO3-N from drinking water was not associated with risk. Colon cancer risks were non-significantly associated with the average TTHM levels >17.7 μg/L (HRQ5vsQ1 = 1.13, CI = 0.89–1.44; ptrend = 0.11) and were elevated for any duration of exposure >1/2-MCL. Rectal cancer risks were associated with the highest TTHM levels (HRQ5vsQ1 = 1.71, CI = 1.00–2.92; ptrend = 0.22) but not with years >1/2-MCL. Bromodichloromethane (HRQ4vsQ1 = 1.89, CI = 1.17–3.00; ptrend = 0.09) and trichloroacetic acid (HRQ4vsQ1 = 1.92, CI = 1.20–3.09; ptrend = 0.18) levels were also associated with risk of rectal cancer. We found no evidence of interaction between TTHM and NO3-N on the risk of either cancer. Dietary analyses yielded a positive colon cancer association with red meat, but not with processed meat intake or estimated nitrate/nitrite from specific dietary sources.
Our results suggest that exposure to TTHM in drinking water is associated with increased risk of rectal cancer. Positive findings for individual THMs and HAAs for both colon and rectal cancers require replication in other studies. We found no associations for nitrate overall or in subgroups with presumed higher NOC exposure.
•Nitrate in drinking water was not associated with risk of colon or rectal cancers.•Exposure to total trihalomethanes in drinking water is associated with the risk of rectal cancer.•Risks of colon and rectal cancers associated with other disinfection byproducts are plausible and require replication.•Red meat intake was associated with colon cancer risk.
PURPOSE The 2007 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) diet and physical activity guidelines encourage cancer survivors to follow its cancer prevention ...recommendations. We evaluated whether adherence to the WCRF/AICR recommendations was associated with health-related quality of life (HRQOL) among elderly female cancer survivors. PATIENTS AND METHODS A total of 2,193 women with a confirmed cancer diagnosis (1986 through 2002) in the Iowa Women's Health Study were identified. We calculated a WCRF/AICR recommendation adherence score (range, 0 to 7), assigning one point each for seven recommendations. Physical and mental component summary scores (PCS, MCS) from the Medical Outcomes Study Short Form-36 Health Survey were compared by recommendation adherence scores. Results Mean adherence score was 4.0 ± 1.2. Overall, higher adherence to the WCRF/AICR guidelines was significantly associated with better PCS and MCS after adjustment for age, education, marital status, number of comorbidities, smoking, cancer stage, and current cancer treatment (Ptrend < .001 for both). PCS was 43.5 versus 37.0 and MCS was 54.2 versus 52.0 among women with adherence scores ≥ 5 compared with women scoring ≤ 3. Adherence to the physical activity recommendation was associated with higher PCS and MCS after adjusting for demographic and medical confounders, body mass index, and dietary recommendation adherence. For the body weight recommendation, adherence was associated with higher PCS but lower MCS, whereas adherence to the dietary recommendations was associated with higher MCS only. CONCLUSION Following the lifestyle guidelines for cancer prevention may improve HRQOL among elderly female cancer survivors. Physical activity may be a key lifestyle factor to improve HRQOL.
The obesity-lung cancer association remains controversial. Concerns over confounding by smoking and reverse causation persist. The influence of obesity type and effect modifications by race/ethnicity ...and tumor histology are largely unexplored.
We examined associations of body mass index (BMI), waist circumference (WC), and waist-hip ratio (WHR) with lung cancer risk among 1.6 million Americans, Europeans, and Asians. Cox proportional hazard regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) with adjustment for potential confounders. Analyses for WC/WHR were further adjusted for BMI. The joint effect of BMI and WC/WHR was also evaluated.
During an average 12-year follow-up, 23 732 incident lung cancer cases were identified. While BMI was generally associated with a decreased risk, WC and WHR were associated with increased risk after controlling for BMI. These associations were seen 10 years before diagnosis in smokers and never smokers, were strongest among blacks, and varied by histological type. After excluding the first five years of follow-up, hazard ratios per 5 kg/m2 increase in BMI were 0.95 (95% CI = 0.90 to 1.00), 0.92 (95% CI = 0.89 to 0.95), and 0.89 (95% CI = 0.86 to 0.91) in never, former, and current smokers, and 0.86 (95% CI = 0.84 to 0.89), 0.94 (95% CI = 0.90 to 0.99), and 1.09 (95% CI = 1.03 to 1.15) for adenocarcinoma, squamous cell, and small cell carcinoma, respectively. Hazard ratios per 10 cm increase in WC were 1.09 (95% CI = 1.00 to 1.18), 1.12 (95% CI = 1.07 to 1.17), and 1.11 (95% CI = 1.07 to 1.16) in never, former, and current smokers, and 1.06 (95% CI = 1.01 to 1.12), 1.20 (95% CI = 1.12 to 1.29), and 1.13 (95% CI = 1.04 to 1.23) for adenocarcinoma, squamous cell, and small cell carcinoma, respectively. Participants with BMIs of less than 25 kg/m2 but high WC had a 40% higher risk (HR = 1.40, 95% CI = 1.26 to 1.56) than those with BMIs of 25 kg/m2 or greater but normal/moderate WC.
The inverse BMI-lung cancer association is not entirely due to smoking and reverse causation. Central obesity, particularly concurrent with low BMI, may help identify high-risk populations for lung cancer.
The etiology of testicular germ cell tumors (TGCT) is poorly understood, however, exposure to endocrine disrupting chemicals (EDCs) may be related to increased risk. Personal care products, some of ...which contain EDCs, are widely used on a daily basis and are known to cross the placenta, be present in breastmilk, and are capable of inducing reproductive tract abnormalities. To determine the association between personal care product use during pregnancy and breastfeeding and TGCT risk, an analysis among mothers of TGCT cases and controls was conducted.
The US Servicemen's Testicular Tumor Environmental and Endocrine Determinants (STEED) study enrolled TGCT cases and controls and their mothers between 2002 and 2005. The current analysis examined personal care product use during pregnancy among 527 mothers of TGCT cases and 562 mothers of controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using unconditional logistic regression adjusting for identified covariates.
Maternal use of face lotion more than one time per week was associated with a significantly increased risk of TGCT (OR: 1.42, 95% CI: 1.08–1.86, p-trend: 0.01). None of the other products examined (perfume, hairspray, nail polish, hair dye, permanent wave, body lotion, deodorant, sunscreen) were associated with TGCT risk.
Frequent exposure to face lotion during pregnancy and while breastfeeding may be associated with increased TGCT risk. Further investigation into the endocrine disrupting effects of personal care products is warranted.
•Face lotion use while pregnant and breastfeeding was associated with an elevated risk of testicular germ cell tumors in sons.•A possible explanation for the association is that face lotion may contain endocrine disrupting chemicals.•Identification of associations with specific chemicals and combinations of chemical formulations of face lotion is warranted.
Data on smoking and second cancer risk among cancer survivors are limited. We assessed associations between smoking before first cancer diagnosis and risk of second primary smoking-associated cancers ...among survivors of lung (stage I), bladder, kidney, and head/neck cancers.
Data were pooled from 2,552 patients with stage I lung cancer, 6,386 with bladder cancer, 3,179 with kidney cancer, and 2,967 with head/neck cancer from five cohort studies. We assessed the association between prediagnostic smoking and second smoking-associated cancer risk with proportional hazards regression, and compared these estimates to those for first smoking-associated cancers in all cohort participants.
Compared with never smoking, current smoking of ≥ 20 cigarettes per day was associated with increased second smoking-associated cancer risk among survivors of stage I lung (hazard ratio HR = 3.26; 95% CI, 0.92 to 11.6), bladder (HR = 3.67; 95% CI, 2.25 to 5.99), head/neck (HR = 4.45; 95% CI, 2.56 to 7.73), and kidney cancers (HR = 5.33; 95% CI, 2.55 to 11.1). These estimates were similar to those for first smoking-associated cancer among all cohort participants (HR = 5.41; 95% CI, 5.23 to 5.61). The 5-year cumulative incidence of second smoking-associated cancers ranged from 3% to 8% in this group of cancer survivors.
Understanding risk factors for second cancers among cancer survivors is crucial. Our data indicate that cigarette smoking before first cancer diagnosis increases second cancer risk among cancer survivors, and elevated cancer risk in these survivors is likely due to increased smoking prevalence. The high 5-year cumulative risks of smoking-associated cancers among current smoking survivors of stage I lung, bladder, kidney, and head/neck cancers highlight the importance of smoking cessation in patients with cancer.
Vitamin D is known for maintaining Ca homeostasis and bone structure, and may also decrease susceptibility to chronic and infectious diseases. However, data on vitamin D status and its predictors ...among Southeast Asian populations are limited. We evaluated the distribution and determinants (genetic and environmental) of serum 25-hydroxyvitamin D (25(OH)D) concentrations among 504 middle-aged and elderly participants (aged 45–74 years) in the Singapore Chinese Health Study. Data on dietary and other lifestyle factors were collected by trained interviewers. Serum 25(OH)D concentrations and genetic polymorphisms in vitamin D metabolism pathway enzymes (cytochrome P450 (CYP) 2R1, 3A4, 27B1, 24A1; vitamin D binding protein (also known as group-specific component, GC); and vitamin D receptor) were measured using stored biospecimens. Mean 25(OH)D concentration was 68·8 nmol/l. Serum 25(OH)D concentrations were positively associated with dietary vitamin D intake, and inversely associated with hours spent sitting at work. BMI was not associated with 25(OH)D concentrations. CYP2R1 rs10741657, rs12794714, rs1993116; CYP3A4 rs2242480; and GC rs4588, rs7041, rs16847015, rs2298849 were statistically significantly associated with 25(OH)D concentrations. Individuals with the Gc2-2 haplotype (rs4588AA/rs7041TT) had statistically significantly lower 25(OH)D concentrations compared to all other Gc haplotypes (P-trend < 0·001). The majority of participants (86 %) had 25(OH)D concentrations ≥ 50 nmol/l, which is consistent with the 2011 Institute of Medicine (US) recommendation for bone health, and 32 % had concentrations of ≥ 75 nmol/l that are thought to be required for broader health effects. Dietary vitamin D intake, hours spent indoors at work and genetic variation in CYP2R1, CYP3A4 and GC are significant predictors of 25(OH)D concentrations among Singapore Chinese.
BackgroundFew studies have evaluated environmental chemical exposures in relation to ovarian cancer. We previously found an increased risk of ovarian cancer among postmenopausal women in Iowa ...associated with higher nitrate levels in public water supplies (PWS). However, elevated nitrate levels may reflect the presence of other agricultural chemicals, such as atrazine, one of the most commonly detected pesticides in Iowa PWS.MethodsWe evaluated the association between atrazine in drinking water and incident ovarian cancer (N=145, 1986–2010) among 13 041 postmenopausal women in the Iowa Women's Health Study who used their PWS for ≥11 years as reported in 1989. Average levels of atrazine (1986–1987), nitrate-nitrogen (NO3-N, 1955–1988) and estimated levels of total trihalomethanes (TTHM, 1955–1988) from PWS monitoring data were linked to the participants' cities of residence. We computed HRs and 95% CIs by categories of the average atrazine level (not detected, ≤ or >0.37 parts per billion=median) using Cox proportional hazards regression adjusting for ovarian cancer risk factors.ResultsAtrazine was detected in water samples from 69 cities where 4155 women (32%) lived and levels were moderately correlated with NO3-N (ρ=0.35) and TTHM (ρ=0.24). Atrazine levels were not associated with ovarian cancer risk with or without adjusting for NO3-N and TTHM levels (p-trend=0.50 and 0.81, respectively). Further, there was no evidence for effect modification of the atrazine association by NO3-N or TTHM levels.ConclusionsIn our study with low atrazine detection rates, we found no association between atrazine in PWS and postmenopausal ovarian cancer risk.
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