Background. Enterotoxigenic Bacteroides fragilis (ETBF) produces the Bacteroides fragilis toxin, which has been associated with acute diarrheal disease, inflammatory bowel disease, and colorectal ...cancer (CRC). ETBF induces colon carcinogenesis in experimental models. Previous human studies have demonstrated frequent asymptomatic fecal colonization with ETBF, but no study has investigated mucosal colonization that is expected to impact colon carcinogenesis. Methods. We compared the presence of the bft gene in mucosal samples from colorectal neoplasia patients (cases, n = 49) to a control group undergoing outpatient colonoscopy for CRC screening or diagnostic workup (controls, n = 49). Single bacterial colonies isolated anaerobically from mucosal colon tissue were tested for the bft gene with touch-down polymerase chain reaction. Results. The mucosa of cases was significantly more often bft-positive on left (85.7%) and right (91.7%) tumor and/or paired normal tissues compared with left and right control biopsies (53.1%; P = .033 and 55.5%; P = .04, respectively). Detection of bft was concordant in most paired mucosal samples from individual cases or controls (75% cases; 67% controls). There was a trend toward increased bft positivity in mucosa from late- vs early-stage CRC patients (100% vs 72.7%, respectively; P = .093). In contrast to ETBF diarrheal disease where bft-1 detection dominates, bft-2 was the most frequent toxin isotype identified in both cases and controls, whereas multiple bft isotypes were detected more frequently in cases (P ≤ .02). Conclusions. The bft gene is associated with colorectal neoplasia, especially in late-stage CRC. Our results suggest that mucosal bft exposure is common and may be a risk factor for developing CRC.
Abstract Purpose To assess the prevalence of erectile dysfunction and to quantify associations between putative risk factors and erectile dysfunction in the US adult male population. Methods ...Cross-sectional analysis of data from 2126 adult male participants in the 2001-2002 National Health and Nutrition Examination Survey (NHANES). Erectile dysfunction assessed by a single question during a self-paced, computer-assisted self-interview. These data are nationally representative of the noninstitutionalized adult male population in the US. Results The overall prevalence of erectile dysfunction in men aged ≥20 years was 18.4% (95% confidence interval CI, 16.2-20.7), suggesting that erectile dysfunction affects 18 million men (95% CI, 16-20) in the US. The prevalence of erectile dysfunction was highly positively related to age but was also particularly high among men with one or more cardiovascular risk factors, men with hypertension, and men with a history of cardiovascular disease, even after age adjustment. Among men with diabetes, the crude prevalence of erectile dysfunction was 51.3% (95% CI, 41.9-60.7). In multivariable analyses, erectile dysfunction was significantly and independently associated with diabetes, lower attained education, and lack of physical activity. Conclusions The high prevalence of erectile dysfunction among men with diabetes and hypertension suggests that screening for erectile dysfunction in these patients may be warranted. Physical activity and other measures for the prevention of cardiovascular disease and diabetes may prevent decrease in erectile function.
There is evidence that diet and nutrition are modifiable risk factors for several cancers, but associations may be flawed due to inherent biases. Nutritional epidemiology studies have largely relied ...on a single assessment of diet using food frequency questionnaires. We conduct an umbrella review of meta-analyses of observational studies to evaluate the strength and validity of the evidence for the association between food/nutrient intake and risk of developing or dying from 11 primary cancers. It is estimated that only few single food/nutrient and cancer associations are supported by strong or highly suggestive meta-analytic evidence, and future similar research is unlikely to change this evidence. Alcohol consumption is positively associated with risk of postmenopausal breast, colorectal, esophageal, head & neck and liver cancer. Consumption of dairy products, milk, calcium and wholegrains are inversely associated with colorectal cancer risk. Coffee consumption is inversely associated with risk of liver cancer and skin basal cell carcinoma.
While evidence is increasingly consistent with a positive association between periodontitis and cancer risk, most studies have relied on self-reported periodontitis. In this study, we prospectively ...evaluated the association of periodontal disease severity with cancer risk in black and white older adults in a cohort study that included a dental examination.
Included were 7466 participants in the Atherosclerosis Risk in Communities study cohort who at visit 4 (1996-1998) reported being edentulous or underwent the dental examination. Probing depth and gingival recession were measured at six sites on all teeth; these measurements were used to define periodontal disease severity. Incident cancers (n = 1648) and cancer deaths (n = 547) were ascertained during a median of 14.7 years of follow-up. All statistical tests were two-sided.
An increased risk of total cancer (hazard ratio HR = 1.24, 95% confidence interval CI = 1.07 to 1.44, Ptrend = .004) was observed for severe periodontitis (>30% of sites with attachment loss >3 mm) compared with no/mild periodontitis (<10% of sites with attachment loss >3 mm), adjusting for smoking and other factors. Strong associations were observed for lung cancer (HR = 2.33, 95% CI = 1.51 to 3.60, Ptrend < .001), and elevated risks were noted for colorectal cancer for severe periodontitis, which were significant among never smokers (HR = 2.12, 95% CI = 1.00 to 4.47). Associations were generally weaker, or not apparent among black participants, except for lung and colorectal cancers, where associations were similar by race. No associations were observed for breast, prostate, or hematopoietic and lymphatic cancer risk.
This study provides additional evidence that cancer risk, especially for lung and colorectal cancer, is elevated in individuals with periodontitis. Additional research is needed to understand cancer site-specific and racial differences in findings.
Experimental and epidemiological studies suggest a protective role for vitamin D in colorectal carcinogenesis, but evidence is inconclusive. Circulating 25-hydroxyvitamin D (25(OH)D) concentrations ...that minimize risk are unknown. Current Institute of Medicine (IOM) vitamin D guidance is based solely on bone health.
We pooled participant-level data from 17 cohorts, comprising 5706 colorectal cancer case participants and 7107 control participants with a wide range of circulating 25(OH)D concentrations. For 30.1% of participants, 25(OH)D was newly measured. Previously measured 25(OH)D was calibrated to the same assay to permit estimating risk by absolute concentrations. Study-specific relative risks (RRs) for prediagnostic season-standardized 25(OH)D concentrations were calculated using conditional logistic regression and pooled using random effects models.
Compared with the lower range of sufficiency for bone health (50-<62.5 nmol/L), deficient 25(OH)D (<30 nmol/L) was associated with 31% higher colorectal cancer risk (RR = 1.31, 95% confidence interval CI = 1.05 to 1.62); 25(OH)D above sufficiency (75-<87.5 and 87.5-<100 nmol/L) was associated with 19% (RR = 0.81, 95% CI = 0.67 to 0.99) and 27% (RR = 0.73, 95% CI = 0.59 to 0.91) lower risk, respectively. At 25(OH)D of 100 nmol/L or greater, risk did not continue to decline and was not statistically significantly reduced (RR = 0.91, 95% CI = 0.67 to 1.24, 3.5% of control participants). Associations were minimally affected when adjusting for body mass index, physical activity, or other risk factors. For each 25 nmol/L increment in circulating 25(OH)D, colorectal cancer risk was 19% lower in women (RR = 0.81, 95% CI = 0.75 to 0.87) and 7% lower in men (RR = 0.93, 95% CI = 0.86 to 1.00) (two-sided Pheterogeneity by sex = .008). Associations were inverse in all subgroups, including colorectal subsite, geographic region, and season of blood collection.
Higher circulating 25(OH)D was related to a statistically significant, substantially lower colorectal cancer risk in women and non-statistically significant lower risk in men. Optimal 25(OH)D concentrations for colorectal cancer risk reduction, 75-100 nmol/L, appear higher than current IOM recommendations.
There has been a marked increase in testosterone prescriptions in the past decade resulting in a growing need to give practicing clinicians proper guidance on the evaluation and management of the ...testosterone deficient patient.
A systematic review utilized research from the Mayo Clinic Evidence Based Practice Center and additional supplementation by the authors. Evidence-based statements were based on body of evidence strength Grade A, B, or C and were designated as Strong, Moderate, and Conditional Recommendations with additional statements presented in the form of Clinical Principles or Expert Opinions (table 1 in supplementary unabridged guideline, http://jurology.com/).
This guideline was developed by a multi-disciplinary panel to inform clinicians on the proper assessment of patients with testosterone deficiency and the safe and effective management of men on testosterone therapy. Additional statements were developed to guide the clinician on the appropriate care of patients who are at risk for or have cardiovascular disease or prostate cancer as well as patients who are interested in preserving fertility.
The care of testosterone deficient patients should focus on accurate assessment of total testosterone levels, symptoms, and signs as well as proper on-treatment monitoring to ensure therapeutic testosterone levels are reached and symptoms are ameliorated. Future longitudinal observational studies and clinical trials of significant duration in this space will improve diagnostic techniques and treatment of men with testosterone deficiency as well as provide more data on the adverse events that may be associated with testosterone therapy.
We evaluated the association of central versus overall adiposity on levels of thyroid stimulating hormone (TSH), free triiodothyronine (fT(3)), and free thyroxine (fT(4)) among euthyroid subjects ...taken from a cross-sectional, representative sample of the adult non-institutionalized U.S. population.
The National Health and Nutrition Examination Survey 2007-2008 included 1,623 men and 1,491 women who were 20 years and older, with no history of thyroid or liver disease, kidney failure, diabetes, or thyroid function-altering prescription medication use (based on self-report), and having TSH, fT(3), and fT(4) levels between 0.5-4.49 mIU/L, 2.5-3.9 pg/mL, and 0.6-1.6 ng/dL, respectively. Associations between body mass index (BMI) and waist circumference (measures of overall and central adiposity, respectively) and TSH, fT(3), and fT(4) levels were estimated using multivariable linear regression models stratified by sex and adjusted for age, race, smoking status, and alcohol intake.
An increase in serum TSH levels was observed for every 1-quartile increase in BMI in euthyroid men (3.8% 95% CI 0.8%, 6.8%) and euthyroid women (4.0% 95% CI 1.6%, 6.5%). Similar, albeit slightly weaker, associations were observed with waist circumference. We also found increases in fT(3) levels with every 1-quartile increase in BMI (1.0% in men and 1.3% in women) and waist circumference (1.2% in men and 1.2% in women). No associations were observed with fT(4.)
Our results provide support that BMI and waist circumference are positively associated with levels of serum TSH and f T(3) but not fT(4) among euthyroid adults. Longitudinal studies are needed to define the temporality of these associations and their potential health implications.
Abstract
Few studies have comprehensively investigated the association of 2 key kidney disease measures, estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (ACR), ...with cancer incidence. In 8,935 participants at the baseline (1996–1998) from the Atherosclerosis Risk in Communities study, we quantified the associations of eGFR (based on creatinine and cystatin C) and ACR with cancer risk using Cox regression models adjusted for potential confounders. Due to changing guidelines for prostate cancer screening during the follow-up period, we investigated overall cancer, overall nonprostate cancer, and site-specific cancer. During a median follow-up of 14.7 years, 2,030 incident cancer cases occurred. In demographically adjusted models, low eGFR and high ACR were associated with cancer incidence (both overall and overall nonprostate cancer). These associations were attenuated after adjusting for other shared risk factors, with a significant association remaining only for ACR (≥103 compared with 5 mg/g) and overall nonprostate cancer. For site-specific cancer, only high ACR showed a significant association with lung and urinary tract cancers. Of these, the association between ACR and lung cancer appeared most robust in several sensitivity analyses. Kidney disease measures, particularly high ACR, were independently associated with cancer risk. The association between ACR and lung cancer was uniquely robust, warranting future studies to explore potential mechanisms.
Summary
Objective A small randomized controlled trial suggested that vitamin D might increase the production of testosterone in men, which is supported by experimental studies in animals and a ...cross‐sectional study showing positive associations between plasma 25‐hydroxyvitamin D 25(OH)D and testosterone and concordant seasonal variation of both biomarkers.
Design and Measurements We investigated the cross‐sectional association of plasma 25(OH)D levels and total and free testosterone measured by immunoassay in 1362 male participants of the Health Professionals Follow‐up Study who were selected for a nested case–control study on prostate cancer using multivariate‐adjusted linear and restricted cubic spline regression models.
Results 25(OH)D was positively associated with total and free testosterone levels. From the lowest to the highest 25(OH)D quintile, multivariate‐adjusted means (95% confidence interval) were 18·5 (17·7; 19·4), 19·4 (18·6; 20·2), 19·6 (18·8; 20·4), 20·1 (19·3; 20·9) and 20·0 (19·1; 20·8; P‐trend = 0·003) for total testosterone and 97·7 (93·9; 101·5), 98·2 (94·1; 102·2), 99·2 (95·2; 103·2), 100·7 (96·9; 104·5) and 101·5 (97·6; 105·4; P‐trend = 0·03) for free testosterone. The shapes of the dose–response curves indicate that the association between 25(OH)D and total and free testosterone is linear at lower levels of 25(OH)D (below approximately 75–85 nmol/l), reaching a plateau at higher levels. Unlike for 25(OH)D, we did not observe any seasonal variation of testosterone concentrations.
Conclusion This study supports previously reported positive associations between vitamin D and testosterone although we did not observe parallel seasonal variation patterns. Possible causality and direction of the vitamin D–testosterone association deserve further scientific investigation.
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