Introduction Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 minute, and has been postulated as a neurobiological dysfunction with genetic vulnerability for the short IELTs, related to disturbances of central serotonin (5-hydroxytryptamine [5-HT]) neurotransmission and 5-HT receptor functioning. Aim To investigate the relationship between 5-HT transporter gene-linked polymorphism (5-HTTLPR) and short IELTs in men with lifelong PE. Methods A prospective study was conducted in 89 Dutch Caucasian men with lifelong PE. IELT during coitus was assessed by stopwatch over a 1-month period. Controls consisted of 92 Dutch Caucasian men. All men with LPE were genotyped for a 5-HTT-promoter polymorphism. Allele frequencies and genotypes of short (S) and long (L) variants of 5-HTTLPR polymorphism were compared between patients and controls. Association between LL, SL, and SS genotypes, and the natural logarithm of the IELT in men with LPE was investigated. Main Outcome Measures IELT measured by stopwatch, 5-HTTLPR polymorphism. Results In men with lifelong PE, the geometric mean, median, and natural mean IELTs were 21, 26, and 32 seconds, respectively. There were no significant differences in the 5-HTT polymorphism alleles and genotypes between 89 Dutch Caucasian men with LPE (S 47%, L 53%/LL 29%, SL 48%, SS 22%) and 92 Dutch Caucasian controls (S 48%, L 52%/LL 29%, SL 45%, SS 26%). In men with lifelong PE there was a statistically significant difference between LL, SL, and SS genotypes in their geometric mean IELT (P ≤ 0.027); the LL genotypes had significantly shorter IELTs than the SS and SL genotypes. Conclusions The 5-HTTLPR polymorphism is associated with significant effects on the latency to ejaculate in men with lifelong PE. Men with SS and SL genotypes have 100% and 90% longer ejaculation time, respectively than men with LL genotypes.

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Previous studies on metformin use and gastrointestinal (GI) cancer risk have yielded inconclusive results on metformin's chemoprotective effects. We aimed to evaluate GI cancer risk in users of metformin in The Netherlands using a time-varying approach in a large population-based database. A cohort study was performed using the NCR-PHARMO database. Patients using ≥1 non-insulin antidiabetic drug (NIAD) during 1998 to 2011 were included ( = 57,621). Exposure to NIADs was modeled time-varyingly. Cox regression analysis estimated HRs of GI cancers in current metformin users versus current users of other NIADs. Covariables included age, sex, drugs known to impact cancer risk, history of hospitalization, and starting year of follow-up. A sensitivity analysis was performed, applying a new-user design. Current use of metformin was not associated with a decreased risk of GI cancer [HR, 0.97; 95% confidence interval (CI), 0.82-1.15] or specific GI cancer sites. The sensitivity analysis yielded comparable results. No decreasing trends were observed with increasing cumulative dose of metformin [HR 1.05, 95% CI, 0.85-1.28; HR 0.89, 95% CI, 0.73-1.10; HR 0.96, 95% CI, 0.77-1.19 for dose tertiles low (<405 g), medium (405-999 g), and high (≥999 g)]. In contrast, an increased risk of pancreatic cancer was found in current users of metformin plus insulin (HR, 4.90; 95% CI, 2.64-9.10). In conclusion, no decreased risk of GI cancer was found in current metformin users compared with current users of other NIADs. Variations in the exposure definition of metformin use may be one of the explanations of previously found reduced cancer risks in metformin users. .

PurposeTo find the most accurate mathematical description of the intravaginal ejaculation latency time (IELT) distribution in the general male population.Materials and MethodsWe compared the fitness of various well-known mathematical distributions with the IELT distribution of two previously published stopwatch studies of the Caucasian general male population and a stopwatch study of Dutch Caucasian men with lifelong premature ejaculation (PE). The accuracy of fitness is expressed by the Goodness of Fit (GOF). The smaller the GOF, the more accurate is the fitness.ResultsThe 3 IELT distributions are gamma distributions, but the IELT distribution of lifelong PE is another gamma distribution than the IELT distribution of men in the general male population. The Lognormal distribution of the gamma distributions most accurately fits the IELT distribution of 965 men in the general population, with a GOF of 0.057. The Gumbel Max distribution most accurately fits the IELT distribution of 110 men with lifelong PE with a GOF of 0.179. There are more men with lifelong PE ejaculating within 30 and 60 seconds than can be extrapolated from the probability density curve of the Lognormal IELT distribution of men in the general population.ConclusionsMen with lifelong PE have a distinct IELT distribution, e.g., a Gumbel Max IELT distribution, that can only be retrieved from the general male population Lognormal IELT distribution when thousands of men would participate in a IELT stopwatch study. The mathematical formula of the Lognormal IELT distribution is useful for epidemiological research of the IELT.

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PurposeTo investigate the association between the 5-HT-transporter-gene-linked promoter region (5-HTTLPR) polymorphism and 20-mg paroxetine-induced ejaculation delay in men with lifelong premature ejaculation (LPE).Materials and MethodsThis was a prospective study of 10 weeks of paroxetine treatment in 54 men with LPE. Intravaginal ejaculation latency time (IELT) was measured by stopwatch. Controls consisted of 92 Caucasian men. All men with LPE were genotyped for the 5-HTTLPR polymorphism. Allele frequencies and genotypes of short (S) and long (L) variants of the polymorphism were compared between patients and controls. Associations between the LL, SL, and SS genotypes and fold increase of mean IELT were investigated.ResultsOf the 54 patients, 43 (79.6%) responded to 20-mg paroxetine treatment with an ejaculation delay, whereas 11 patients (20.4%) did not respond; 44%, 18%, and 18% of the patients showed a fold increase in mean IELT of 2-10, 10-20, and more than 20, respectively. Of the 54 men, 14 (25.9%) had the LL genotype, 29 (53.7%) had the SL genotype, and 11 (20.4%) had the SS genotype. In the 92 controls, the LL, SL, and SS genotypes were present in 27 (29.3%), 41 (44.6%), and 24 (26.1%), respectively. No statistically significant differences were found in 5-HTTLPR allelic variations or in 5-HTTLPR gene variations. In all men treated with 20 mg paroxetine, analysis of variance of the natural logarithm of fold increase in the IELT showed no statistically significant difference according to genotype (p=0.83).ConclusionsThe 5-HTTLPR polymorphism is not associated with daily 20-mg paroxetine treatment-induced ejaculation delay in men with LPE.

ObjectiveTo analyze a recently published meta-analysis of six studies on 5-HTTLPR polymorphism and lifelong premature ejaculation (PE).MethodsCalculation of fraction observed and expected genotype frequencies and Hardy Weinberg equilibrium (HWE) of cases and controls. LL,SL and SS genotype frequencies of patients were subtracted from genotype frequencies of an ideal population (LL25%, SL50%, SS25%, p = 1 for HWE). Analysis of PCRs of six studies and re-analysis of the analysis and Odds ratios (ORs) reported in the recently published meta-analysis.ResultsThree studies deviated from HWE in patients and one study deviated from HWE in controls. In three studies in-HWE the mean deviation of genotype frequencies from a theoretical population not-deviating from HWE was small: LL(1.7%), SL(−2.3%), SS(0.6%). In three studies not-in-HWE the mean deviation of genotype frequencies was high: LL(−3.3%), SL(−18.5%) and SS(21.8%) with very low percentage SL genotype concurrent with very high percentage SS genotype. The most serious PCR deviations were reported in the three not-in-HWE studies. The three in-HWE studies had normal OR. In contrast, the three not-in-HWE studies had a low OR.ConclusionsIn three studies not-in-HWE and with very low OR, inadequate PCR analysis and/or inadequate interpretation of its gel electrophoresis resulted in very low SL and a resulting shift to very high SS genotype frequency outcome. Consequently, PCRs of these three studies are not reliable. Failure to note the inadequacy of PCR tests makes such PCRs a confounding factor in clinical interpretation of genetic studies. Currently, a meta-analysis can only be performed on three studies-in-HWE. However, based on the three studies-in-HWE with OR of about 1 there is not any indication that in men with lifelong PE the frequency of LL,SL and SS genotype deviates from the general male population and/or that the SL or SS genotype is in any way associated with lifelong PE.

Cefuroxime clearance by RCA-CVVH was twice the reported clearance during standard CVVH. Our PK data predicted that a maintenance dose of 3000 mg cefuroxime, infused over 24 hours, would provide an optimal steady-state plasma concentration of 38.5 mg/L. The developed population PK model for cefuroxime has the potential to inform new dosing schedules in patients receiving cefuroxime during RCA-CVVH.