Do transsexuals have micturition disorders?

OBJECTIVE: Transsexualism occurs with an estimated prevalence of 2.4:100,000 male-to-female (MTF) and 1:100,000 female-to-male (FTM) transsexuals. As sex reassignment surgery involves surgery of the urethra and transsexuals are substituted life-long with the cross gender hormones there could possibly arise micturition disorders. Aim of the study was to determine if transsexuals have an increased risk of micturition disorders and if so which. STUDY DESIGN: Between January and July 2003 we examined 25 transsexuals whereof 18 were MTF and 7 were FTM transsexuals using King's Health Questionnaire, visual analogue scale for patient's well being, perineal and transabdominal ultrasound, urine dipstick and uroflow measurement. RESULTS: 17 out of 25 patients considered themselves very happy. In MTF transsexuals, a diverted stream, overactive bladder and stress urinary incontinence was a common problem. Prostate volume was small with 20 g and palpation did not confirm and solid or suspicious lesions. None of the patients had significant residual urine but MTF transsexuals had a reduced urinary flow. We could not detect a current urinary tract infections in any of the patients. CONCLUSION: Transsexuals have an increased risk for the development of micturition disorders including stress urinary incontinence and overactive bladder compared to age-matched control groups and should be counselled preoperatively. Reasons for the development of incontinence might be surgery including pudendal nerve damage, hormonal reasons and ageing.

Selenium for preventing cancer

BACKGROUND This review is an update of the first Cochrane publication on selenium for preventing cancer (Dennert 2011).Selenium is a metalloid with both nutritional and toxicological properties. Higher selenium exposure and selenium supplements have been suggested to protect against several types of cancers. OBJECTIVES Two research questions were addressed in this review: What is the evidence for:1. an aetiological relation between selenium exposure and cancer risk in humans? and2. the efficacy of selenium supplementation for cancer prevention in humans? SEARCH METHODS We conducted electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL, 2013, Issue 1), MEDLINE (Ovid, 1966 to February 2013 week 1), EMBASE (1980 to 2013 week 6), CancerLit (February 2004) and CCMed (February 2011). As MEDLINE now includes the journals indexed in CancerLit, no further searches were conducted in this database after 2004. SELECTION CRITERIA We included prospective observational studies (cohort studies including sub-cohort controlled studies and nested case-control studies) and randomised controlled trials (RCTs) with healthy adult participants (18 years of age and older). DATA COLLECTION AND ANALYSIS For observational studies, we conducted random effects meta-analyses when five or more studies were retrieved for a specific outcome. For RCTs, we performed random effects meta-analyses when two or more studies were available. The risk of bias in observational studies was assessed using forms adapted from the Newcastle-Ottawa Quality Assessment Scale for cohort and case-control studies; the criteria specified in the Cochrane Handbook for Systematic Reviews of Interventions were used to evaluate the risk of bias in RCTs. MAIN RESULTS We included 55 prospective observational studies (including more than 1,100,000 participants) and eight RCTs (with a total of 44,743 participants). For the observational studies, we found lower cancer incidence (summary odds ratio (OR) 0.69, 95% confidence interval (CI) 0.53 to 0.91, N = 8) and cancer mortality (OR 0.60, 95% CI 0.39 to 0.93, N = 6) associated with higher selenium exposure. Gender-specific subgroup analysis provided no clear evidence of different effects in men and women (P value 0.47), although cancer incidence was lower in men (OR 0.66, 95% CI 0.42 to 1.05, N = 6) than in women (OR 0.90, 95% CI 0.45 to 1.77, N = 2). The most pronounced decreases in risk of site-specific cancers were seen for stomach, bladder and prostate cancers. However, these findings have limitations due to study design, quality and heterogeneity that complicate interpretation of the summary statistics. Some studies suggested that genetic factors may modify the relation between selenium and cancer risk-a hypothesis that deserves further investigation.In RCTs, we found no clear evidence that selenium supplementation reduced the risk of any cancer (risk ratio (RR) 0.90, 95% CI 0.70 to 1.17, two studies, N = 4765) or cancer-related mortality (RR 0.81, 95% CI 0.49 to 1.32, two studies, N = 18,698), and this finding was confirmed when the analysis was restricted to studies with low risk of bias. The effect on prostate cancer was imprecise (RR 0.90, 95% CI 0.71 to 1.14, four studies, N = 19,110), and when the analysis was limited to trials with low risk of bias, the interventions showed no effect (RR 1.02, 95% CI 0.90 to 1.14, three studies, N = 18,183). The risk of non-melanoma skin cancer was increased (RR 1.44, 95% CI 0.95 to 1.17, three studies, N = 1900). Results of two trials-the Nutritional Prevention of Cancer Trial (NPCT) and the Selenium and Vitamin E Cancer Trial (SELECT)-also raised concerns about possible increased risk of type 2 diabetes, alopecia and dermatitis due to selenium supplements. An early hypothesis generated by NPCT that individuals with the lowest blood selenium levels at baseline could reduce their risk of cancer, particularly of prostate cancer, by increasing selenium intake has not been confirmed by subsequent trials. As the RCT participants were overwhelmingly male (94%), gender differences could not be systematically assessed. AUTHORS' CONCLUSIONS Although an inverse association between selenium exposure and the risk of some types of cancer was found in some observational studies, this cannot be taken as evidence of a causal relation, and these results should be interpreted with caution. These studies have many limitations, including issues with assessment of exposure to selenium and to its various chemical forms, heterogeneity, confounding and other biases. Conflicting results including inverse, null and direct associations have been reported for some cancer types.RCTs assessing the effects of selenium supplementation on cancer risk have yielded inconsistent results, although the most recent studies, characterised by a low risk of bias, found no beneficial effect on cancer risk, more specifically on risk of prostate cancer, as well as little evidence of any influence of baseline selenium status. Rather, some trials suggest harmful effects of selenium exposure. To date, no convincing evidence suggests that selenium supplements can prevent cancer in humans.