The relationship between subjective and objective assessments of sacral neuromodulation effectiveness in patients...

Global response assessment (GRA) has been used to evaluate patients' perceptions of treatment effectiveness. However, few studies have scrutinized the relationship between GRAs and objective voiding diary outcomes data. This study explores the relationship between self-reported symptom-specific GRA responses and objective changes in frequency, urgency and pelvic pain in patients with urgency-frequency with or without pelvic pain after implantation of a prosthetic sacral nerve stimulation device.

Patients scheduled for a staged procedure were enrolled in a prospective, observational, longitudinal study. Post implantation, patietns were grouped into "responders" or "non-responders" based on their answers to symptom-specific GRAs at three and six months. Treatment responders were defined as those reporting "moderately" or "markedly improved" on a 7-point scale, and all others were considered non-responders. Pre- and post-implant changes in mean 24-hour voiding frequency, voided volume, urgency and pelvic pain scores as recorded on voiding diaries were compared between groups using paired t-test.

At three months, responders demonstrated corresponding statistically significant improvement in voiding frequency (P < 0.001), average voided volume (P = 0.003), urgency (P = 0.022) and pelvic pain (P = 0.039). At six months, responders demonstrated statistically significant improvements in frequency (P = 0.025) and urgency (P = 0.006). None of the symptom changes were statistically significant in treatment non-responders.

The GRA non-responders groups' perceptions of treatment response agreed with their objective changes in bothersome symptoms and responders' changes agreed with their perception of improvement in the majority of symptoms. Further study is needed to standardize the GRA, and explore its potential for use in clinical practice.