Local Estrogen Adherence Prospective Study

Objectives: Local estrogen therapy (LET) has many benefits, but little is known regarding adherence and reasons for discontinuation. We aimed to evaluate fill/continuation rates of LET and assess factors associated with not filling/discontinuation and changes in formulation.

Methods: This is a prospective observational cohort of English-speaking adult women that were prescribed LET in a Urogynecology practice from March 1st 2022 to March 31st, 2023. Women who used LET within the past 3 months were excluded. Eligible patients were contacted and verbal consent obtained. Demographic and clinical data were gathered through chart review. Participants completed electronic or telephone treatment satisfaction questionnaires, Pelvic Floor Distress Inventory 20 (PFDI-20) and the Day-to-Day Impact of Vaginal Aging (DIVA) at baseline, 3, 6, and 12 months from initial prescription for those continuing therapy. Participants who discontinued LET were queried regarding reason for discontinuation. Change in validated questionnaire scores from baseline to 3-, 6-, and 12-months between medication filled and not filled was compared with unpaired t-tests. Discontinuation was analyzed by logistic regression.

Results: 1302 prescriptions were screened, 512 were eligible, 150 could not be contacted, 121 declined participation, resulting in 241 women enrolled with 155 completing initial assessments (Figure 1). Of those who completed initial assessment, mean age was 65 (+/-10), 62% were white and 57% had private insurance. The most common primary indications for therapy were atrophic vaginitis (39%) and recurrent urinary tract infection (22%). Most common formulations were cream (81%) and tablet (13%). At baseline, 94% filled the initial prescription. Continuation rates were 78%, 90%, and 79% at 3, 6, and 12 months respectively, but 93 (60%) were lost to follow-up over the entire study period. The most common reasons for not starting LET included cost (33%) and concern for side effects (22%). Common reasons for discontinuing were mess (19%) and concern for side effects (16%). PFDI summary score and DIVA domains of activities of daily living, emotional well-being and sexual function scores decreased across all timepoints for all participants with no difference between women who continued versus discontinued LET. Univariate analysis did not find an association between formulation, primary indication or demographic factors and LET discontinuation.

Conclusions: LET use is associated with improvement in pelvic floor discomfort and vaginal discomfort at 3-, 6- and 12-months following initiation. Prospective evaluation of fill/ continuation was challenging due to low enrollment and high loss to follow-up. Among participants in a tertiary practice, 26% discontinued LET over 1-year. Barriers to initiation and discontinuation such as cost, mess and concern for side effects are potentially modifiable factors that physicians can address to improve adherence. We found no identifiable factors that correlated with discontinuing therapy but were likely underpowered to detect differences that may exist.