Genetic Factors Associated with Absolute and Relative Plasma Concentrations of Calcitriol.

BACKGROUND: Little is known regarding factors associated with calcitriol and a relative measure of calcitriol, the calcitriol-24,25-dihydroxyvitamin D3-calcifediol proportion ratio (C24CPR). METHODS: Using a cross-sectional study design, healthy young adults of African and European descent, matched (1:1) on age (±5 years) provided a blood sample in non-summer months (N = 376). Vitamin D metabolites were measured in plasma with HPLC/MS-MS. West African genetic ancestry proportion (WGA) was estimated using STRUCTURE modeling of genetic ancestry-informative markers. Multivariable regression models were used to estimate the association of WGA and vitamin D-pathway gene variants with calcitriol and C24CPR, controlling for days from summer solstice, age, sex, blood pressure, body mass index, dietary vitamin D intake, oral contraceptive/medroxyprogesterone acetate use, smoking, tanning bed use, and time of day. RESULTS: Calcitriol and C24CPR were not highly correlated (rho = 0.14), although both were significantly, positively, and monotonically associated with WGA (Ptrend 0.025 and <0.001, respectively). In fully adjusted models, genetic factors explained a greater proportion of variability in C24CPR (R2 = 0.121 and 0.310, respectively). Variants in genes with associated with calcitriol (CALB1, CYP27B1, GC, and PPARGC1A) differed from those associated with C24CPR (CYP3A43, FGF23, KL, and VDR). CONCLUSIONS: Both absolute and relative measures of calcitriol were significantly higher among African Americans. Otherwise, these biomarkers appear to be genetically distinct. IMPACT: C24CPR may be better suited to personalized medicine, due to a higher proportion of population variability explained by genetic variation and a less skewed distribution.

The case for using mixed methods for designing, implementing, and disseminating evidence-based interventions for public health practice.

A well-recognized gap exists between findings from public health research and their use in public health practice to improve outcomes. The World Health Organization (WHO) has identified implementation research as vital to improving the adaptation and dissemination of public health interventions into real-world settings. Implementation research encompasses multimethod evaluation approaches; 'mixed methods', the planned integration of qualitative and quantitative methods, is a key tool. We argue that mixed methods designs are crucial for design and evaluation of public health interventions, provide illustrative case studies, discuss key analytic approaches in mixed methods design, identify resources for mixed methods research and advocate for more training. On behalf of the International Network for Epidemiology in Policy (INEP), an international non-profit organization of 24 member societies that promotes the development of equitable, evidence-based health policies, we call for increased collaboration between qualitative and quantitative research teams to improve the design and evaluation of public health interventions.

Coffee intake and trace element blood concentrations in association with renal cell cancer among smokers.

PURPOSE: To determine whether higher coffee intake may reduce the risk of renal cell cancer (RCC) associated with lead (Pb) and other heavy metals with known renal toxicity. METHODS: We conducted a nested case-control study of male smokers (136 RCC cases and 304 controls) within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Cases diagnosed with RCC at 5 or more years following cohort enrollment were matched to controls on age (± 7 years) and whole blood draw date (± 30 days). Conditional logistic regression (using two-sided tests) was used to test for main effects and additive models of effect modification. RESULTS: After a mean follow-up of 16.3 years, coffee consumption was not significantly associated with renal cell cancer risk, when adjusting for blood concentrations of Cd, Hg, and Pb and RCC risk factors (age, smoking, BMI, and systolic blood pressure) (p-trend, 0.134). The association with above median blood Pb and RCC (HR = 1.69, 95% CI 1.06, 2.85) appeared to be modified by coffee consumption, such that RCC risk among individuals with both increased coffee intake and higher blood lead concentration were more than threefold higher RCC risk (HR = 3.40, 95% CI 1.62, 7.13; p-trend, 0.003). CONCLUSION: Contrary to our initial hypothesis, this study suggests that heavy coffee consumption may increase the previously identified association between higher circulating lead (Pb) concentrations and increased RCC risk. Improved assessment of exposure, including potential trace element contaminants in coffee, is needed.

Vitamin D and family history of hypertension in relation to hypertension status among college students.

Hypertension and vitamin D concentrations have heritable components, although these factors remain uninvestigated in young adults. The objective of this study was to investigate hypertension risk among young adults with respect to family history of hypertension, adjusting for vitamin D status. Resting blood pressure (BP) was measured in 398 individuals aged 18-35 and classified according to the 2017 American Heart Association criteria. Plasma vitamin D metabolite (25(OH)D3; 24,25(OH)2D3; 1,25(OH)2D3) concentrations were determined using liquid chromatography tandem mass spectrometry (LC-MS/MS). Stepwise logistic regression was used to select covariates. Participants' mean age was 21, 30.3% had hypertension, and nearly all unaware of their hypertensive status (90.7%). Compared with no parental history, the adjusted odds ratio (AOR) for hypertension was elevated among participants with two parents having hypertension (AOR = 4.5, 95% CI: 1.70-11.76), adjusting for sex, body mass index, physical activity, and plasma 25(OH)D3. Results for systolic hypertension (SH) were similar but more extreme (two parents AOR = 7.1, 95% CI: 2.82, 17.66), although dihydroxy metabolites (1,25(OH)2D3 and 24,25(OH)2D3) were significant. There was a strong, independent association with dual parental history and hypertension status, regardless of vitamin D status. Hypertension was prevalent in nearly one-third of the sample and underscores the need for targeted prevention for young adults.

Efficacy of oil and gas produced water as a dust suppressant.

The effectiveness of oil and gas produced water (OGPW) applied to unpaved roads to reduce particulate matter (PM10) generation has not been well-characterized. Here we quantify the efficacy of OGPW compared to commercial and alternative byproducts as dust suppressants applied to unpaved roads and estimate efficacy of a dust suppressant extrapolated from both lab experiments and published data for OGPW across U.S. states. Both treated and untreated OGPW, simulated brines, and commercial dust suppressants were characterized by major and trace element composition and then applied to road aggregate in the laboratory. PM10 generation after treatment was quantified, both before and after simulated rain events to assess the need for multiple applications. We found the dust suppression efficacy of all OGPW to be less than commercial products and alternative byproducts such as waste soybean oil. In addition, OGPW lost efficacy following simulated rain events, which would require repeated applications of OGPW to maintain dust suppression. The dust suppression efficacy of OGPW can be estimated based on two chemical measurements, the sodium absorption ratio (SAR) and the total dissolved solids (TDS). OGPW with the lowest SAR and highest TDS performed best as dust suppressants while high SAR and lower TDS led to greater dust generation.

Early Preparation and Inspiration for STEM Careers: Preliminary Report of the Epidemiology Challenge Randomized Intervention, 2014-2015.

OBJECTIVES: Early Preparation and Inspiration for Careers in the Biomedical Sciences (EPIC) is a university-high school partnership for increasing high school student interest and persistence in the biomedical sciences. EPIC includes a year-long, project-based learning intervention, the Think Like an Epidemiologist Challenge (Epi Challenge). We describe the main components of the Epi Challenge and report on short-term changes in scientific literacy and science-related motivations and beliefs. METHODS: From June 2014 through June 2015, a randomized sample of students with above-median interest in science from 5 high schools in Pennsylvania completed baseline and midyear assessments of scientific self-efficacy, beliefs regarding acquisition of scientific knowledge (personal scientific epistemology), and personal interest in science using 5-point Likert-type scales (with higher scores indicating stronger or more sophisticated beliefs). RESULTS: Of 984 students completing baseline assessments, 110 enrolled in the Epi Challenge, and 84 remained at midyear. At midyear, mean scores for scientific self-efficacy (change = 0.26, P < .001) and personal scientific epistemology (change = 0.19, P = .004) increased significantly, but personal interest in science (change = -0.17, P = .06) did not. Increases in personal scientific epistemology were greatest for African American (change = 0.47, P = .005), free/reduced-price lunch (change = 0.35, P = .001), underrepresented minorities in science (change = 0.27, P = .002), and female (change = 0.26, P = .01) students. CONCLUSIONS: Epi Challenge participation was associated with improvement in high school students' scientific self-efficacy and sophistication of epistemologic beliefs. Long-term follow-up of this cohort may shed light on whether such changes will be sustained and shape college major and career decisions.

Ancestry-Adjusted Vitamin D Metabolite Concentrations in Association With Cytochrome P450 3A Polymorphisms.

We investigated the association between genetic polymorphisms in cytochrome P450 (CYP2R1, CYP24A1, and the CYP3A family) with nonsummer plasma concentrations of vitamin D metabolites (25-hydroxyvitamin D3 (25(OH)D3) and proportion 24,25-dihydroxyvitamin D3 (24,25(OH)2D3)) among healthy individuals of sub-Saharan African and European ancestry, matched on age (within 5 years; n = 188 in each ancestral group), in central suburban Pennsylvania (2006-2009). Vitamin D metabolites were measured using high-performance liquid chromatography with tandem mass spectrometry. Paired multiple regression and adjusted least-squares mean analyses were used to test for associations between genotype and log-transformed metabolite concentrations, adjusted for age, sex, proportion of West-African genetic ancestry, body mass index, oral contraceptive (OC) use, tanning bed use, vitamin D intake, days from summer solstice, time of day of blood draw, and isoforms of the vitamin D receptor (VDR) and vitamin D binding protein. Polymorphisms in CYP2R1, CYP3A43, vitamin D binding protein, and genetic ancestry proportion remained associated with plasma 25(OH)D3 after adjustment. Only CYP3A43 and VDR polymorphisms were associated with proportion 24,25(OH)2D3. Magnitudes of association with 25(OH)D3 were similar for CYP3A43, tanning bed use, and OC use. Significant least-squares mean interactions (CYP2R1/OC use (P = 0.030) and CYP3A43/VDR (P = 0.013)) were identified. A CYP3A43 genotype, previously implicated in cancer, is strongly associated with biomarkers of vitamin D metabolism. Interactive associations should be further investigated.

Metal-contaminated potato crops and potential human health risk in Bolivian mining highlands.

This study assessed metals in irrigation water, soil and potato crops impacted by mining discharges, as well as potential human health risk in the high desert near the historic mining center of Potosí, Bolivia. Metal concentrations were compared with international concentration limit guidelines. In addition, an ingested average daily dose and minimum risk level were used to determine the hazard quotient from potato consumption for adults and children. Irrigation water maximum concentrations of Cd, Pb and Zn in mining-impacted sites were elevated 20- to 1100-fold above international concentration limit guidelines. Agricultural soils contained total metal concentrations of As, Cd, Pb and Zn that exceeded concentration limits in agricultural soil guidelines by 22-, 9-, 3- and 12-fold, respectively. Potato tubers in mining-impacted sites had maximum concentrations of As, Cd, Pb and Zn that exceeded concentration limits in commercially sold vegetables by 9-, 10-, 16- and fourfold, respectively. Using conservative assumptions, hazard quotients (HQ) for potatoes alone were elevated for As, Cd and Pb among children (range 1.1-71.8), in nearly all of the mining-impacted areas; and for As and Cd among adults (range 1.2-34.2) in nearly all of the mining-impacted areas. Only one mining-impacted area had a Pb adult HQ for potatoes above 1 for adults. Toxic trace elements in a major regional dietary staple may be a greater concern than previously appreciated. Considering the multitude of other metal exposure routes in this region, it is likely that total HQ values for these metals may be substantially higher than our estimates.

Possible health effects of living in proximity to mining sites near Potosí, Bolivia.

OBJECTIVE: The goal of this study was to determine the health effects of living downstream from mines in the Potosí region of Bolivia. METHODS: Histories, physical examinations, and urinalyses were completed on adults recruited from mining and nonmining villages in Bolivia. Blood concentrations of Cd, Hg, and Pb were determined in a subset of participants. Multiple logistic regression analyses were performed. RESULTS: Mining region participants had significantly higher frequencies of hypertension, hematuria, and ketonuria. Hematuria was significantly elevated among those watering livestock downstream from mines and eating grains from their own farm (odds ratio = 4.3; 95% confidence interval, 1.1 to 17.7). Significantly higher blood concentrations of Pb were observed in a subsample of participants with hematuria (4.80 µg/dL vs 10.91 µg/dL; P = 0.026). CONCLUSIONS: Efforts to abate environmental exposure to toxic metals seem warranted.

Genetic and environmental influences on plasma vitamin D binding protein concentrations.

Recent studies suggest that low vitamin D-binding protein (VDBP aka group-specific complement or Gc) concentrations may be linked with inflammatory-mediated conditions, including asthma, chronic obstructive pulmonary disease, and cancer. However, these studies may be confounded by substantial racial and ethnic or genetic differences. The purpose of this study was to test the hypothesis that circulating VDBP concentrations are significantly associated with genetic ancestry. We used a validated high-performance liquid chromatography tandem mass spectrometry assay of 25-hydroxyvitamin D3 and its downstream metabolite 24,25-dihydroxyvitamin D3. VDBP concentrations (milligrams per liter) were measured in duplicate using a commercial enzyme-linked immunosorbent assay among healthy African American (n = 56) and Caucasian American (n = 60) participants. Ancestry informative markers across the genome were used to estimate individual genetic ancestry proportions, designed to robustly distinguish between West African and European ancestry. Genotype-defined Gc isoforms were defined using rs7041 and rs4588 combination groups. VDBP concentration was correlated with both Gc isoform (r = 0.93, P < 0.001) and West African genetic ancestry (r = -0.66, P < 0.001). In the final model, Gc isoform, the catabolic ratio of serum vitamin D, oral contraceptive use, and body mass index remained significantly associated with VDBP concentration, after adjustment for genetic ancestry. Failure to adjust for Gc isoform may lead to spurious associations in studies of VDBP concentration and disease risk, particularly when the condition of interest may also be associated with genetic ancestry. The higher circulating VDBP concentrations and higher vitamin D catabolic rate among Caucasian Americans observed here appear to be consistent with lower bone mineral density and racial and ethnic differences in vitamin D-inducing cytokines.

Lead, calcium uptake, and related genetic variants in association with renal cell carcinoma risk in a cohort of male Finnish smokers.

BACKGROUND: Lead is classified as a probable human carcinogen. However, its role in renal cell cancer (RCC) has not been established. Calcium and vitamin D may off-set toxicity in vivo. METHODS: In this nested case-control study, whole blood lead, total serum calcium, and serum 25-hydroxyvitamin D levels were measured in blood drawn prior to diagnosis among male smokers participating in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Single-nucleotide polymorphisms (SNP) in five genes (CALB1, TRPV5, TRPV6, VDR, and ALAD) related to lead toxicity or calcium transport were genotyped. Logistic and linear regressions were used to determine RCC risk and time to diagnosis (respectively), adjusting for other risk factors. RESULTS: Among 154 newly diagnosed cases and 308 matched controls, RCC was associated with higher whole blood lead [OR = 2.0; 95% confidence interval (CI), 1.0-3.9; quartile 4 (Q4) vs. Q1, P(trend) = 0.022] and CALB1 rs1800645 (P(trend) = 0.025, minor 'T' allele frequency = 0.34). Higher total serum calcium (P(trend) ≤ 0.001) was associated with reduced RCC risk. Total serum calcium and 25-hydroxyvitamin D levels did not alter the association observed with lead. Time from enrollment to RCC diagnosis was positively associated with serum calcium (P(trend) = 0.002) and 25-hydroxyvitamin D (P(trend) = 0.054) among cases. CONCLUSIONS: Higher blood lead concentrations, below the 10 µg/dL level of concern, were associated with RCC, independent from serum calcium and CALB1 promoter polymorphism. IMPACT: Increased risk of RCC is associated with lower serum calcium and higher whole blood lead in smokers. The clinical prognostic value of serum calcium and vitamin D in RCC should be further investigated.

Impact of a community-based intervention on serving and intake of vegetables among low-income, rural Appalachian families.

OBJECTIVE: To evaluate the effectiveness of a community-based intervention promoting the serving and eating of deep-orange, cruciferous, and dark-green leafy vegetables. DESIGN: Randomized, parallel-group, community-based intervention with a baseline/postintervention/3-month follow-up design. SETTING AND PARTICIPANTS: Low-income food preparers (n = 50) and their partners (n = 50) in rural Appalachia Pennsylvania. INTERVENTION: Experimental food preparers attended 8 weekly interactive lessons; control food preparers received 8 weekly mailings that included similar recipes and handouts. MAIN OUTCOME MEASURES: Target vegetable intake and frequency of serving by experimental and control treatment groups and by high and low meal diary scores, a measure of recipe acceptability. ANALYSIS: Linear mixed-model analysis with repeated measures. RESULTS: No significant differences resulted between the original experimental and control treatment groups. When grouped by high and low meal diary scores, more experimental families had high scores than in controls. High scores were associated with significant changes in frequency of serving and intake of the target vegetables. CONCLUSIONS AND IMPLICATIONS: Meal diary use may foster food preparer negotiation with partners and children to become involved in vegetable dish evaluation. Tools to help the trained food preparer draw family members into recipe evaluation, such as the meal diary, are useful and needed.

Breast and cervical cancer screening patterns among American Indian women at IHS clinics in Montana and Wyoming.

OBJECTIVES: We investigated factors associated with primary and secondary breast and cervical cancer screening among American Indian (AI) women receiving care from the Indian Health Service (IHS) in Montana and Wyoming. METHODS: Rates of primary screening (i.e., screening without evidence of a prior abnormal) and secondary screening during a three-year period (2004-2006) were determined in an age- and clinic-stratified random sample of 1,094 women at six IHS units through medical record review. RESULTS: Three-year mammography prevalence rates among AI women aged ≥45 years were 37.7% (95% confidence interval [CI] 34.1, 41.3) for primary and 58.7% (95% CI 43.9, 73.5) for secondary screening. Among women aged ≥18 years, three-year Pap test prevalence rates were 37.8% (95% CI 34.9, 40.6) for primary and 53.2% (95% CI 46.0, 60.4) for secondary screening. Primary mammography screening was positively associated with number of visits and receiving care at an IHS hospital (both p<0.001). Primary Pap test screening was inversely associated with age and positively associated with the number of patient visits (both p<0.001). Secondary mammography screening was inversely associated with driving distance to an IHS facility (p=0.035). CONCLUSION: Our results are consistent with other surveys among AI women, which report that Healthy People 2010 goals for breast (90%) and cervical (70%) cancer screening have not been met. Improvements in breast and cervical cancer screening among AI women attending IHS facilities are needed.

Genetic Ancestry, Skin Reflectance and Pigmentation Genotypes in Association with Serum Vitamin D Metabolite Balance.

BACKGROUND: Lower serum vitamin D (25(OH)D) among individuals with African ancestry is attributed primarily to skin pigmentation. However, the influence of genetic polymorphisms controlling for skin melanin content has not been investigated. Therefore, we investigated differences in non-summer serum vitamin D metabolites according to self-reported race, genetic ancestry, skin reflectance and key pigmentation genes (SLC45A2 and SLC24A5). MATERIALS AND METHODS: Healthy individuals reporting at least half African American or half European American heritage were frequency matched to one another on age (+/- 2 years) and sex. 176 autosomal ancestry informative markers were used to estimate genetic ancestry. Melanin index was measured by reflectance spectrometry. Serum vitamin D metabolites (25(OH)D3, 25(OH)D 2 and 24,25(OH)2D3) were determined by high performance liquid chromatography (HPLC) tandem mass spectrometry. Percent 24,25(OH)2D3 was calculated as a percent of the parent metabolite (25(OH)D3). Stepwise and backward selection regression models were used to identify leading covariates. RESULTS: Fifty African Americans and 50 European Americans participated in the study. Compared with SLC24A5 111Thr homozygotes, individuals with the SLC24A5 111Thr/Ala and 111Ala/Ala genotypes had respectively lower levels of 25(OH)D3 (23.0 and 23.8 nmol/L lower, p-dominant=0.007), and percent 24,25(OH)2D3 (4.1 and 5.2 percent lower, p-dominant=0.003), controlling for tanning bed use, vitamin D/fish oil supplement intake, race/ethnicity, and genetic ancestry. Results were similar with melanin index adjustment, and were not confounded by glucocorticoid, oral contraceptive, or statin use. CONCLUSIONS: The SLC24A5 111Ala allele was associated with lower serum vitamin 25(OH)D3 and lower percent 24,25(OH)2D3, independently from melanin index and West African genetic ancestry.

Fish, vitamin D, and flavonoids in relation to renal cell cancer among smokers.

Fish, vitamin D, flavonoids, and flavonoid-containing foods may have cardiovascular benefits and therefore may also reduce the risk of renal cell cancer. Risk was prospectively assessed in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study (1985-2002) cohort (N = 27,111; 15.2 mean person-years of follow-up). At enrollment, demographic, health, and dietary history information was recorded. Individuals who smoked less than 5 cigarettes/day, with chronic renal insufficiency or prior cancer, were excluded. Hazard ratios and 95% confidence intervals from Cox regression were used to compare upper quartiles (quartiles 2-4) with the lowest quartile (quartile 1) of dietary intake. Among 228 cases, risk (quartile 4 vs. quartile 1) was associated with consumption of the flavonoid quercetin (hazard ratio = 0.6, 95% confidence interval: 0.4, 0.9; P(trend) = 0.015) and Baltic herring (hazard ratio = 2.0, 95% confidence interval: 1.4, 3.0; P(trend) < 0.001), with adjustment for age, body mass index, smoking, blood pressure, alcohol use, physical activity, urban residence, and education. In geographically stratified models, the risks associated with herring and total fish intake appeared to be highest in the urban coast region, although the interaction was not statistically significant. These results suggest that the flavonoid quercetin may prevent renal cell cancer among male smokers. The possible risk associated with fish intake warrants further investigation before conclusions may be drawn.

A novel SNP in a vitamin D response element of the CYP24A1 promoter reduces protein binding, transactivation, and gene expression.

The active form of vitamin D (1alpha,25(OH)(2)D(3)) is known to have antiproliferative effects and has been implicated in cancers of the colon, breast, and prostate. These cancers occur more frequently among African Americans than Caucasians, and individuals with African ancestry are known to have approximately twofold lower levels of serum vitamin D (25(OH)D) compared with individuals of European ancestry. However, epidemiological studies of the vitamin D receptor (VDR) have shown inconsistent associations with cancer risk, suggesting that differences in other genes in the pathway may be important. We sought to identify functionally significant polymorphic variants in CYP24A1, a gene that is highly inducible by 1alpha,25(OH)(2)D(3) and that encodes the primary catabolic enzyme in the pathway. Here we report the identification of six novel SNPs in the human CYP24A1 promoter, including one at nucleotide -279 occurring within the distal vitamin D response element (VDRE2). Our experiments demonstrate that the VDRE2 variant results in decreased protein binding and transactivation in vitro, and reduced expression of CYP24A1 in cultured primary human lymphocytes provides evidence for an effect in vivo. This variant was only observed in our African American population, and represents a first step toward understanding differences in disease risk among racial/ethnic groups.

Cancer among American Indians and Alaska Natives in the United States, 1999-2004.

BACKGROUND: Cancer incidence rates vary among American Indian and Alaska Native (AI/AN) populations and often differ from rates among non-Hispanic whites (NHWs). However, the misclassification of race for AI/AN cancer cases in central cancer registries may have led to underestimates of the AI/AN cancer burden in previous reports. METHODS: Cases diagnosed during 1999 through 2004 were identified from population-based cancer registries in the United States. Age-adjusted rates were calculated for the 25 most common sites for AI/ANs and NHWs. To minimize the misclassification of race, cancer registry records were linked with patient registration files from the Indian Health Service (IHS). Analyses were restricted to Contract Health Service Delivery Area (CHSDA) counties and were stratified by IHS region. RESULTS: In CHSDA counties, cancer incidence rates among AI/ANs varied widely by region, whereas rates among NHWs did not. For all cancer sites combined, AI/AN rates were higher than NHW rates among both males and females in the Northern and Southern Plains, and among Alaska Native Females; AI/AN rates were lower than NHW rates in the Southwest, the Pacific Coast, and the East. Lung cancer and colorectal cancer rates for AI/ANs exceeded rates for NHWs in Alaska and the Northern Plains. Rates for stomach, gallbladder, kidney, and liver cancer were higher among AI/ANs than among NHWs overall, in Alaska, in the Plains regions, and in the Southwest. CONCLUSIONS: Regional differences in cancer incidence rates among AI/AN populations were not obvious from nationwide data and highlighted opportunities for cancer control and prevention. It is unlikely that such differences are explained by race misclassification.

Cancers of the urinary tract among American Indians and Alaska Natives in the United States, 1999-2004.

BACKGROUND: Assessment of the kidney parenchyma ("kidney") and urinary bladder ("bladder") cancer burden among American Indians and Alaska Natives (AI/AN) has been limited. Using a database with improved classification for AI/AN, the authors described patterns of these 2 cancers among AI/AN and non-Hispanic whites (NHW) in the United States. METHODS: Cases diagnosed during 1999 to 2004 were identified through National Program of Cancer Registries and the Surveillance, Epidemiology and End Results program and linked to the Indian Health Service (IHS) registration records. Age-adjusted incidence rates, rate ratios (RR), annual percent change, and stage at diagnosis were stratified by IHS Contract Health Service Delivery Area (CHSDA) counties to adjust for misclassification. RESULTS: Kidney cancer incidence among AI/AN in CHSDA counties exceeded that among NHW (RR, 1.51; 95% confidence interval [CI], 1.42-1.61), and was highest among AI/AN in the Northern Plains, Southern Plains, Alaska, and Southwest. Average annual increases were highest among AI/AN (5.9%) and NHW (5.9%) males aged 20 to 49 years, although statistically significant only among NHW. Conversely, bladder cancer incidence was significantly lower among AI/AN than NHW (RR, 0.40; 95% CI, 0.37-0.44). For both sites, AI/AN were significantly less likely to be diagnosed at an earlier stage than NHW. CONCLUSIONS: AI/AN have about 50% greater risk of kidney cancer and half the risk of bladder cancer than NHW. Although reasons for these enigmatic patterns are not known, sustained primary prevention efforts through tobacco cessation and obesity prevention are warranted.

Shared occupational risks for transitional cell cancer of the bladder and renal pelvis among men and women in Sweden.

BACKGROUND: Unlike cancer of the bladder, cancer of the renal pelvis is not considered an occupational cancer and little is known about risks among women. METHODS: Using the Swedish national census and cancer registry-linked data (1971-1989), we identified transitional cell cancers of the renal pelvis (N = 1,374) and bladder (N = 21,591). Correlation between cancer sites for the standardized incidence ratios (SIR) were determined using Pearson's coefficient of the log SIR. Relative risks of job exposure matrix variables were calculated using Poisson regression. RESULTS: Both cancer sites were significantly elevated among women and men employed in the machine/electronics industry, sedentary work, and indoor work, and men in the metal industry. The highest proportion of the bladder (12%) and renal pelvis (14%) cancers occurred among men employed in shop and construction metal work. Risks by industry were more correlated among women (r = 0.49, P = 0.002) than men (r = 0.24, P = 0.04). Cancers of the renal pelvis were elevated in several occupational and industry groups for which there was no elevated bladder cancer risk. CONCLUSION: Cancers of the renal pelvis and bladder share common occupational risk factors that may be more frequent among women. In addition, there may be some jobs that pose an increased risk specifically for cancer of the renal pelvis but not bladder.