Tamra E. Meyer

Meta-analysis of racial disparities in survival in association with socioeconomic status among men and women with colon cancer.

Few studies have addressed racial disparities in survival for colon cancer by adequately incorporating both treatment and socioeconomic factors, and the findings from those studies have been inconsistent. The objectives of the current study were to systematically review the existing literature and provide a more stable estimate of the measures of association between socioeconomic status and racial disparities in survival for colon cancer by undertaking a meta‐analysis.

Impact of Treatment and Socioeconomic Status on Racial Disparities in Survival Among Older Women With Breast Cancer

Objective:To examine racial/ethnic disparities in mortality and survival in a large nationwide and population-based cohort of women with breast cancer after simultaneously controlling for differences in comorbidity, treatment, and socioeconomic status. Methods:A cohort of 35,029 women with stage I–IIIA breast cancer at age ≥65 from 1992 to 1999 was identified from the surveillance, epidemiology, and end results-medicare linked databases with up to 11 years of follow-up. Cox proportional hazard regression analysis was performed to determine the risk of all-cause and breast cancer-specific mortality. Results:African-American women with breast cancer were more likely to live in the poorest quartiles of socioeconomic status at the census tract level than whites (73.7% versus 20.7%, P < 0.001). Those living in communities with the lowest socioeconomic status were 11% more likely to die than those in the highest (hazard ratio, 1.10; 95% confidence interval, 1.04–1.16). The risk of dying changed slightly after controlling for race/ethnicity (1.11; 1.05–1.18). Compared with white women with breast cancer, crude hazard ratios of all-cause and breast cancer-specific mortality were 1.35 (1.27–1.45) and 1.83 (1.56–2.16) for African-Americans. After adjusting for treatment and socioeconomic status, hazard ratio of all-cause mortality was no longer significant in African-Americans (1.02; 0.84–1.10), whereas the risk of breast cancer-specific mortality was marginally higher in African-Americans (1.21; 1.01–1.46). Conclusions:Racial disparities in overall survival between African-American and white women with breast cancer were not present after controlling for treatment and socioeconomic status. Efforts to eliminate these barriers have important public health implications for reducing disparities in health outcomes.

A case–control study of farming and prostate cancer in African‐American and Caucasian men

Objective: To determine the risk of prostate cancer associated with farming by duration, recency and specific activities among African-Americans and Caucasians. Methods: This population-based case–control study had information on farming-related activities for 405 incident prostate cancer cases and 392 controls matched for age, race and region in South Carolina, USA, from 1999 to 2001. Cases with histologically confirmed, primary invasive prostate cancer who were aged between 65 and 79 years were ascertained through the South Carolina Central Cancer Registry. Appropriately matched controls were identified from the Health Care Financing Administration Medicare Beneficiary File. Data were collected using computer-assisted telephone interviewing, and adjusted odds ratios (aOR) were estimated using unconditional logistic regression. Results: Farming was associated with increased risk of prostate cancer in Caucasians (aOR 1.8; 95% confidence interval (CI) 1.3 to 2.7) but not in African-Americans (aOR 1.0; 95% CI 0.6 to 1.6). Regarding specific farming activities, farmers who mixed or applied pesticides had a higher risk of prostate cancer (aOR 1.6; 95% CI 1.2 to 2.2). Increased risk of prostate cancer was observed only for those farming <5 years. Conclusions: Increased risk of prostate cancer for farmers in this study may be attributable to pesticide exposure. Racial differences in the association between farming and prostate cancer may be explained by different farming activities or different gene–environment interactions by race.

Diabetes Genes and Prostate Cancer in the Atherosclerosis Risk in Communities Study

There is a known inverse association between type 2 diabetes (T2D) and prostate cancer (PrCa) that is poorly understood. Genetic studies of the T2D-PrCa association may provide insight into the underlying mechanisms of this association. We evaluated associations in the Atherosclerosis Risk in Communities study between PrCa and nine T2D single nucleotide polymorphisms from genome-wide association studies of T2D (in CDKAL1, CDKN2A/B, FTO, HHEX, IGF2BP2, KCNJ11, PPARG, SLC30A8, and TCF7L2) and four T2D single nucleotide polymorphisms from pre–genome-wide association studies (in ADRB2, CAPN10, SLC2A2, and UCP2). From 1987 to 2000, there were 397 incident PrCa cases among 6,642 men ages 45 to 64 years at baseline. We used race-adjusted Cox proportional hazards models to estimate associations between PrCa and increasing number of T2D risk-raising alleles. PrCa was positively associated with the CAPN10 rs3792267 G allele [hazard ratio (HR) 1.20; 95% confidence interval (CI), 1.00-1.44] and inversely associated with the SLC2A2 rs5400 Thr110 allele (HR, 0.85; 95% CI, 0.72, 1.00), the UCP2 rs660339 Val55 allele (HR, 0.84; 95% CI, 0.73, 0.97) and the IGF2BP2 rs4402960 T allele (HR, 0.79; 95% CI, 0.61-1.02; blacks only). The TCF7L2 rs7903146 T allele was inversely associated with PrCa using a dominant genetic model (HR, 0.79; 95% CI, 0.65-0.97). Further knowledge of T2D gene-PrCa mechanisms may improve understanding of PrCa etiology. Cancer Epidemiol Biomarkers Prev; 19(2); 558–65

Adherence to Recommendations for Follow-up to Abnormal Pap Tests

OBJECTIVE: To evaluate whether timely adherence rates differ by race among women with abnormal Pap tests participating in a cost-free or reduced-cost program. METHODS: Eligible subjects included women aged 47–64 years who received a referral for follow-up care after an abnormal Pap test from 1999 to 2002 in South Carolina (n=330). Adherence was measured as days to receipt of follow-up care after an abnormal Pap test. Cox proportional hazards modeling was used to estimate risk factors associated with time to adherence within 60 and 365 days by race. RESULTS: African-American and non-Hispanic white women had similar adherence to follow-up. Among white women, those with high-grade lesions were less likely to adhere in a timely manner relative to those with low-grade lesions (hazard ratio 0.6, 95% confidence interval [CI] 0.4–1.0). For African-American women, rural residence (hazard ratio: 0.5, 95% CI 0.2–0.9) and history of abnormal Pap tests (hazard ratio 0.6, 95% CI 0.3–1.0) were associated with decreased adherence, whereas less education (hazard ratio 2.3, 95% CI 1.3–3.9) was associated with increased adherence. CONCLUSION: Adherence rates do not differ by race. However, risk factors for adherence within race are variable. Interventions tailored to the differential needs of racial and ethnic groups may prove effective toward increasing timely adherence rates. LEVEL OF EVIDENCE: II

Serological evidence of typhus group rickettsia in a homeless population in Houston, Texas

ABSTRACT We tested sera from 176 homeless people in Houston for antibodies against typhus group rickettsiae (TGR). Sera from 19 homeless people were reactive to TGR antigens by ELISA and IFA. Two people had antibodies against Rickettsia prowazekii (epidemic typhus) and the remaining 17 had antibodies against Rickettsia typhi (murine typhus).

Measuring Serum Melatonin in Epidemiologic Studies

Background: Epidemiologic data on serum melatonin, a marker of circadian rhythms, and cancer are sparse due largely to the lack of reliable assays with high sensitivity to detect relatively low melatonin levels in serum collected during daylight, as commonly available in most epidemiologic studies. Methods: To help expand epidemiologic research on melatonin, we assessed the reproducibility and refined a currently available melatonin RIA, and evaluated its application to epidemiologic investigations by characterizing melatonin levels in serum, urine, and/or plasma in 135 men from several ethnic groups. Results: Reproducibility was high for the standard 1.0-mL serum [mean coefficient of variation (CV), 6.9%; intraclass correlation coefficient (ICC), 97.4%; n = 2 serum pools in triplicate] and urine-based (mean CV, 3.5%; ICC, 99.9%) assays. Reproducibility for the 0.5-mL refined-serum assay was equally good (mean CV, 6.6%; ICC, 99.0%). There was a positive correlation between morning serum melatonin and 6-sulfatoxymelatonin in 24-hour urine (r = 0.46; P = 0.008; n = 49 subjects). Melatonin levels in serum-plasma pairs had a high correlation (r = 0.97; P < 1×10−4; n = 20 pairs). Morning serum melatonin levels were five times higher than those from the afternoon (before 9 a.m. mean, 11.0 pg/mL, versus after 11 a.m. mean, 2.0 pg/mL). Chinese men had lower melatonin levels (mean, 3.4 pg/mL), whereas Caucasian, African-American, and Ghanaian men had similar levels (mean, 6.7-8.6 pg/mL). Conclusions: These results suggest that melatonin can be detected reliably in serum samples collected in epidemiologic studies in various racial groups. Impact: With improved assays, it may be possible to investigate the role of melatonin and the emerging circadian rhythm hypothesis in cancer etiology in epidemiologic studies. Cancer Epidemiol Biomarkers Prev; 19(4); 932–7. ©2010 AACR.

West Nile virus infection among the homeless, Houston, Texas.

Among 397 homeless participants studied, the overall West Nile virus (WNV) seroprevalence was 6.8%. Risk factors for WNV infection included being homeless >1 year, spending >6 hours outside daily, regularly taking mosquito precautions, and current marijuana use. Public health interventions need to be directed toward this high-risk population.

GOSR2 Lys67Arg Is Associated With Hypertension in Whites

BACKGROUND Hypertension is a risk factor for coronary heart disease (CHD), but the causes of hypertension remain largely unknown. Genetic variation is thought to contribute to the etiology of hypertension. We tested a single-nucleotide polymorphism (SNP) (Lys67Arg, rs197922) in the Golgi SNAP Receptor Complex Member 2 (GOSR2) gene for association with hypertension and blood pressure (BP). We chose this SNP because it was nominally associated with CHD in earlier studies. Further, GOSR2 is located in a linkage region for hypertension and BP in human and animal studies. METHODS We used logistic and linear regression to test associations of the GOSR2 SNP with hypertension and BP among 3,528 blacks and 9,861 whites from the Atherosclerosis Risk in Communities (ARIC) study. Race-specific regression models of hypertension were adjusted for age and gender. Regression models of BP were further adjusted for antihypertensive medication use. RESULTS The GOSR2 Lys67 allele was associated with hypertension in whites (odds ratio (OR) = 1.09, P = 0.01) but not blacks (OR = 0.96, P = 0.47). The Lys67 allele was associated with increased systolic BP (SBP) in both races (0.87 mm Hg, P < 0.001 among whites and 1.05 mm Hg, P = 0.05 among blacks). A similar association in whites was observed for the GOSR2 SNP and SBP in the Womens Genome Health Study (WGHS) (OR = 1.03, P = 0.04). The OR remained unchanged after adjustment for antihypertensive medication use (OR = 1.03, P = 0.11), though it was no longer statistically significant. CONCLUSIONS We found evidence that a SNP in GOSR2 is modestly associated with hypertension in whites from the ARIC study and the WGHS.