The effects of repeat fractional CO2 laser for postmenopausal vaginal symptoms following unblinding from a double-blind RCT.

OBJECTIVE

This study aimed to explore the effects of blinding on patient-reported outcomes.

METHOD: Findings from this prospective open-label extension study were compared to a previous double-blind sham-controlled randomized trial. Women with any postmenopausal vaginal symptom previously receiving either active or sham vaginal fractional CO2 laser were recruited from the index randomized controlled trial (RCT), and underwent an active laser protocol. Symptom severity was assessed by co-primary outcomes of a visual analog scale (VAS) for overall and most bothersome symptom and the Vulvovaginal Symptom Questionnaire (VSQ) to 12 months.

RESULTS

Of the 25 participants, there was a significant improvement in the co-primary outcomes at 6 months from baseline (mean difference: overall vaginal symptoms VAS, 22.0 [95% confidence interval (CI) -32.2, -11.8]; most bothersome symptom VAS, -22.1 [95% CI -36.7, -7.5]; VSQ, -2.2 [95% CI -3.8, -0.6]). At 12 months, there was significant improvement in most bothersome symptom VAS (-17.8 [95% CI -35.3, -0.3]) and VSQ (-2.3 [95% CI -3.9, -0.8]) scores. There was no significant difference in the post-treatment improvement of the co-primary outcomes at 6 and 12 months following open-label laser treatment, when compared to index RCT outcomes following active laser and sham laser treatment, respectively.

CONCLUSION

Blinding in randomized trials is essential for correctly interpreting clinical outcomes using lasers for genitourinary symptoms of menopause.