Botulinum toxin in women’s health: An update

Long-term Effects of Repeated Botulinum Toxin Injection in Cosmetic Therapeutics

BACKGROUND

Botulinum toxin (BT), a potent neurotoxin, has been used in clinical medicine since the 1970s for cosmetic and therapeutic purposes. Studies have consistently shown positive outcomes with a very limited adverse effect profile and a conventional understanding that results dissipate after 3 to 5 months. However, more recent evidence suggests that changes in muscle composition, function, and appearance persist for much longer, even years. To examine the potential implications of these findings on cosmetic use of BT injections in reduction of skin lines and wrinkles, we first needed to further our understanding of the current literature on long-term outcomes after repeated BT injections.

METHODS

A comprehensive review of the literature on long-term outcomes after repeated BT injections for cosmetic indications was performed. We evaluated the study designs, and results were compared.

RESULTS

A total of 22 publications met our inclusion criteria, of which 14 were clinical trials. Few studies extended outcome measurement past 6 months postinjection, and many were funded or supported by industry. However, the studies that extended follow-up saw persistent changes after BT injection, in some cases as far as 4 years postinjection.

CONCLUSION

The current body of knowledge on the long-term results after repeated cosmetic BT injections is very limited, and the available literature provides insufficient evidence on how prolonged effects could alter clinical use of BT. Further clinical studies with extended follow-up periods with inclusion of both subjective and objective measured outcomes of appearance and muscle function are required to better understand the long-term impacts of repeated BT injections.

Routine Office Assessment After OnabotulinumtoxinA Injection for Overactive Bladder Is Unnecessary to Detect Clinically Significant Voiding Dysfunction

OBJECTIVE

This study aimed to determine if routine assessment of patients after onabotulinumtoxinA injections for overactive bladder is necessary to detect clinically significant voiding dysfunction.

METHODS

This retrospective cross-sectional cohort study analyzed patients who underwent intravesical injection of onabotulinumtoxinA for overactive bladder during a 4-year period. Patients were included for analysis if they returned for an office follow-up visit within 1 month of administration. Baseline demographic data; procedural details; postvoid residual volumes; abnormal postprocedure voiding symptoms, including urinary frequency, pain, or inability to void; urinary tract infections; and initiation of intermittent self-catheterization were recorded. Descriptive statistics, point-biserial and Pearson correlation analyses were performed.

RESULTS

Two hundred thirty-seven injections were included in our analysis. Fifteen encounters, from 13 patients, required the initiation of intermittent self-catheterization (6.3%). The median postvoid residual in those treated with intermittent self-catheterization was 300 mL (min, max: 200, 750 mL); all had received 100 units of onabotulinumtoxinA. The most common symptom among those requiring intermittent self-catheterization was urgency (n = 13; 87%), whereas 93% (n = 14) had at least 1 bothersome symptom. Correlation analyses showed a weak positive correlation with elevated postvoid residual volume and a history of prolapse repair (r = 0.269, P = 0.004), and prior pelvic surgery (r = 0.205, P = 0.029).

CONCLUSIONS

Clinically relevant urinary retention that required intermittent self-catheterization after onabotulinumtoxinA injection for overactive bladder occurred in 6.3% of participants in this sample. The vast majority of patients who required intermittent self-catheterization described symptoms that they were able to self-identify.