Sun-seeking behavior to increase cutaneous vitamin D synthesis: when prevention messages conflict.

Objectives: The public has long been encouraged to engage in sun-safe practices to minimize exposure to sunlight, the major cause of nonmelanoma skin cancer. More recently, some have advocated unprotected sun exposure to increase cutaneous synthesis of vitamin D as a way to promote health. We assessed the net result of these conflicting messages.

Body-mass index and mortality among 1.46 million white adults.

Background: A high body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) is associated with increased mortality from cardiovascular disease and certain cancers, but the precise relationship between BMI and all-cause mortality remains uncertain.

Methods: We used Cox regression to estimate hazard ratios and 95% confidence intervals for an association between BMI and all-cause mortality, adjusting for age, study, physical activity, alcohol consumption, education, and marital status in pooled data from 19 prospective studies encompassing 1.46 million white adults, 19 to 84 years of age (median, 58).

Natural history of celiac disease autoimmunity in a USA cohort followed since 1974.

Background: The natural history and the possible changes of celiac disease (CD) prevalence over time are still unclear.

Objectives: 1) To establish whether loss of tolerance to gluten may occur at any age; 2) to investigate possible changes of CD prevalence over time; and 3) to investigate CD-related co-morbidities.

Methods: We analyzed 3,511 subjects with matched samples from 1974 (CLUE I) and 1989 (CLUE II).

Association between C-peptide concentration and prostate cancer incidence in the CLUE II cohort study.

Diabetes, characterized by perturbations in insulin production and signaling, is inversely associated with prostate cancer risk irrespective of stage. Obesity, a diabetes risk factor, is inversely associated with localized disease but positively associated with advanced disease. To understand the complex association between hyperinsulinemia and prostate cancer, we evaluated the association of plasma C-peptide, an insulin secretion marker, with prostate cancer risk in a case-control study nested in a prospective community cohort.

Involving stakeholders to optimize a study protocol on secondhand tobacco smoke and chronic rhinosinusitis in adults.

Background: Epidemiological evidence evaluating the association between secondhand smoke exposure and diseases of the upper airway in adults is limited by a small number of studies and a lack of established protocols. This study was designed to optimize a research protocol on secondhand tobacco smoke exposure and chronic rhinosinusitis for a future population-based case-control study in Washington County, Maryland, using a participatory research model.

Methods: We conducted three focus groups with health professionals, community members, and research practitioners for protocol development; 10 one-on-one cognitive testings with community members for protocol refinement; and a pilot testing of the full study protocol (10 cases and 10 controls) for full evaluation of the study protocol.

Secondhand tobacco smoke exposure and chronic rhinosinusitis: a population-based case-control study.

Background: Rhinosinusitis is a costly disease that adversely affects quality of life (QOL). It is known to be influenced by environmental factors, but few studies have evaluated the association between secondhand tobacco smoke (SHS) exposure and chronic rhinosinusitis (CRS). To address this evidence gap, we evaluated the association of SHS and CRS risk in a community-based case-control study of adult nonsmokers.

Association between plasma total cholesterol concentration and incident prostate cancer in the CLUE II cohort.

Statin drugs appear to protect against advanced and possibly high-grade prostate cancer, perhaps through cholesterol-lowering. Thus, we evaluated the association between plasma cholesterol and prostate cancer. We conducted a prospective study in the CLUE II cohort of Washington County, MD.

Metabolic syndrome components and colorectal adenoma in the CLUE II cohort.

Background: Metabolic syndrome components have been associated with colorectal cancer in several studies; however, evidence for colorectal adenomas is limited. Thus, we evaluated the association between markers of the metabolic syndrome with colorectal adenoma development in a nested case-control study.

Methods: Colorectal adenoma cases (n = 132) and matched controls, who had a negative sigmoidoscopy or a colonoscopy (n = 260), were identified between baseline in 1989 and 2000 among participants in the CLUE II cohort of Washington County, Maryland.

Association of common polymorphisms in IL10, and in other genes related to inflammatory response and obesity with colorectal cancer.

Objective And Methods: The association of 17 candidate single nucleotide polymorphisms (SNPs) in IL10 and other immune response genes (CRP, TLR4, IL6, IL1B, IL8, TNF, RNASEL) and genes related to obesity (PPARG, TCF7L2, ADIPOQ, LEP) with colorectal cancer was investigated. Haplotype tagging SNPs were chosen for IL10, CRP, and TLR4. Incident colorectal cancer cases (n = 208) and matched controls (n = 381) were identified between baseline in 1989 and 2003 among participants in the CLUE II cohort.

Association of IL10 and other immune response- and obesity-related genes with prostate cancer in CLUE II.

Background: Chronic intra-prostatic inflammation and obesity are thought to influence prostate carcinogenesis. Thus, variants in genes in these pathways could be associated with prostate cancer risk.

Methods: We genotyped 17 common single nucleotide polymorphisms (SNPs) in RNASEL, TLR4, IL1B, IL6, IL8, IL10, TNF, CRP, ADIPOQ, LEP, PPARG, and TCF7L2 in 258 white prostate cancer cases and 258 matched controls nested in CLUE II.