Effect Size in Efficacy Trials of Women With Decreased Sexual Desire

The Sexual Incentive Motivation Model and Its Clinical Applications

Sexual motivation (desire) requires the simultaneous presence of an active central motive state and a stimulus with sexual significance. Once activated, sexual motivation leads to visceral responses and approach behaviors directed toward the emitter of the sexual stimulus. In humans, such behaviors follow cognitive evaluation of the context, including predictions of the approached individual's response. After successful approach and establishment of physical contact, manifest sexual activities may be initiated. Sexual interaction is associated with and followed by a state of positive affect in most animals, whereas aversive consequences may be experienced by humans. The affective reactions may become associated with stimuli present during sexual interaction, and these stimuli may thereby alter their incentive properties. Here we show how the incentive motivation model can be used to explain the origins and possible treatments of sexual dysfunctions, notably disorders of desire. We propose that associations formed between negative outcomes of sexual interaction and the salient stimuli, for example, the partner, underlies hypoactive desire disorder. Highly positive outcomes of sexual interaction enhance the incentive value of the stimuli present, and eventually lead to hyperactive sexual desire. Treatments aim to alter the impact of sexual incentives, mainly by modifying cognitive processes.

Effects of Flibanserin on Subdomain Scores of the Female Sexual Function Index in Women With Hypoactive Sexual Desire Disorder

INTRODUCTION

Flibanserin treatment increases sexual desire and satisfying sexual events while decreasing distress in certain women diagnosed with acquired, generalized hypoactive sexual desire disorder (HSDD). Additional aspects of sexual function and the time course of response have not been fully characterized.

AIM

To evaluate changes in sexual function assessed by the subdomains of the Female Sexual Function Index (FSFI) in women with HSDD treated with flibanserin.

METHODS

FSFI data pooled from 3 pivotal flibanserin trials in premenopausal women (flibanserin = 1,165; placebo = 1,203) and FSFI data from one complete flibanserin trial in postmenopausal women (flibanserin = 432; placebo = 463) were subjected to post-hoc analyses. For each FSFI subdomain, least squares mean change from baseline was calculated at each assessment visit (treatment weeks 4, 8, 16, 24) and treatment groups were compared using analysis of covariance. Standardized effect size (Cohen's d) was also determined for each FSFI subdomain.

MAIN OUTCOME MEASURE

Changes from baseline in FSFI subdomains.

RESULTS

Compared to placebo, both premenopausal (P < .02) and postmenopausal (P < .045) patients in the flibanserin group reported significantly greater increases over baseline in the FSFI subdomain scores of desire, arousal, lubrication, orgasm, and satisfaction. In premenopausal patients, significant improvements were observed at the first assessment of response (week 4) and were maintained through week 24. In postmenopausal patients, significant improvements were observed at week 4 for desire and arousal, while significant improvements in lubrication, orgasm, and satisfaction were observed at week 8. At week 24, excluding the pain subdomain, standardized effect sizes ranged from 0.18 to 0.28 in the premenopausal cohort and 0.12 to 0.29 in the postmenopausal cohort. In both pre- and postmenopausal patients, improvements in pain were smaller and largely undifferentiated between treatment groups.

CLINICAL IMPLICATIONS

While variations in time to response should be taken into consideration, on average, the beneficial impact of flibanserin on overall sexual function occurs within the first month of treatment. The data also suggest that the response to flibanserin is sustained for the duration of treatment.

STRENGTHS AND LIMITATIONS

Sexual function assessments were performed in a large cohort of 2,368 premenopausal women and 895 postmenopausal women. However, the FSFI assesses changes over a 1-month period and time points earlier than 4 weeks could not be assessed.

CONCLUSION

These analyses suggest that assessment of benefit of flibanserin in HSDD should include improvements across all domains of sexual function, not only desire. Simon JA, Clayton AH, Goldstein I, et al. Effects of Flibanserin on Subdomain Scores of the Female Sexual Function Index in Women With Hypoactive Sexual Desire Disorder. Sex Med 2022;10:100570.

Behavioral Therapies for Treating Female Sexual Dysfunctions: A State-of-the-Art Review

Many possible factors impact sexual wellbeing for women across the lifespan, and holistic approaches are being utilized to promote health and to address sexual concerns. Female sexual dysfunction disorders, including female orgasmic disorder, female sexual interest/arousal disorder and genito-pelvic pain/penetration disorder, negatively impact quality of life for many women. To reduce distress and improve sexual functioning, numerous behavioral therapies have been tested to date. Here, we present a state-of-the-art review of behavioral therapies for female sexual dysfunction disorders, focusing on empirically validated approaches. Multiple psychotherapies have varying degrees of support, with cognitive-behavioral and mindfulness-based therapies arguably having the most empirical support. Nonetheless, several limitations exist of the studies conducted to date, including the frequent grouping together of multiple types of sexual dysfunctions in randomized clinical trials. Thus, additional research is needed to advance treatment development for female sexual dysfunctions and to promote female sexual health.