Relevance of Methodological Design for the Interpretation of Efficacy of Drug Treatment of Premature Ejaculation: A Systematic Review and Meta-Analysis

M.D. Waldinger; A.H. Zwinderman; D.H. Schweitzer; B. Olivier

Int J Impot Res. 2004;16(4) 

In This Article

Abstract and Introduction

The aim of this systematic review and meta-analysis is to evaluate whether the design and methodology of drug-treatment studies of premature ejaculation affect the efficacy outcome differently. Therefore, methodological, design and efficacy data from 79 studies (3034 males), published between 1943 and 2003, are reviewed. A meta-analysis is performed on 43 selective serotonin reuptake inhibitors (SSRIs) and clomipramine studies (1514 males), published between 1973 and 2003; these studies were pooled to provide a summary variance-weighted effect size. The antidepressant-induced percentage increase of the intravaginal ejaculation latency time (IELT) was calculated and examined against various methodological items. A significant difference in efficacy between SSRIs was observed. Using daily treatment, paroxetine appeared more effective than the other SSRIs. Retrospective use of a questionnaire, subjective reports, single-blind and open study designs generate far greater variability of ejaculation time both at baseline and during active drug treatment than real time assessment by stopwatch. In conclusion, at daily treatment, the overall efficacy of paroxetine, clomipramine, sertraline and fluoxetine is comparable, but paroxetine exerts the strongest ejaculation delay. Only eight (18.5%) studies on antidepressant treatment fulfilled all criteria used in evidence-based medicine, for example, randomised, double-blind studies with prospective real time (stopwatch) assessment of the IELT at each intercourse. Single-blind studies, open designs, retrospective reporting, or the use of a questionnaire to assess ejaculation time should be avoided.

Some selective serotonin reuptake inhibitors (SSRIs) and clomipramine have increasingly become the agents of first choice for the treatment of lifelong premature ejaculation.[1,2,3] Based on animal[4] and human psychopharmacological studies, Waldinger et al have postulated that lifelong premature ejaculation is a neurobiological phenomenon related to decreased central serotonergic neurotransmission, 5-HT2C receptor hyposensitivity and/or 5-HT1A hypersensitivity.[5,6,7] In addition, Waldinger postulates that lifelong early ejaculation is not an acquired disorder due to learned behavior, as has been suggested by Masters and Johnson, but, instead, belongs to the normal biological variability of the intravaginal ejaculation latency time (IELT) in men, with a possible familial genetic vulnerability.[1,5,6,7,8,9] In this sense, early ejaculation is considered a neurobiological phenomenon, that may become perceived as premature ejaculation and consequently may secondarily lead to psychological distress.[1]

Due to many practical difficulties sexual psychopharmacological research is subjected to, it is questioned whether the methodology of research is of relevance for clinical outcome.[10,11] The way to address the issue of methodological bias is to perform a systematic review of the complete literature and to perform a meta-analysis on all data. Such a meta-analysis on methodology and drug treatment has not been performed yet on this issue. Consequently, there is no evidence-based consensus on methodology in research and treatment.[11]

In the current study, a review was performed on all available drug-treatment studies, published between 1943 and 2003, and a meta-analysis was conducted on all studies using serotonergic antidepressants for the daily and as-needed treatment of premature ejaculation.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: