Lower Urinary Tract Symptoms in Myasthenia Gravis

It remains uncertain to what extent lower urinary tract (LUT) symptom (LUTS) is a comorbidity of myasthenia gravis (MG). We prospectively administered a LUTS questionnaire devised for detecting neurogenic pelvic organ dysfunction (not validated) in an MG group and a healthy control group and compared the results. The MG group comprised 21 patients: 15 women and 6 men, with age range 22–73 (mean 47) years, illness duration range 0.2–8 (mean 3.5) years, median Myasthenia Gravis Foundation of America (MGFA) grade 2, all walking independently. Therapies included thymectomy in 17, predonisolone 5–20 mg/day in 10, and pyridostigmine bromide 60–180 mg/day in 9 patients. The control group, who were undergoing an annual health survey, comprised 235 consecutive subjects: 120 women and 115 men, with age range 30–69 (mean 48) years. The questionnaire had 9 questions. Each question was scored from 0 (none) to 3 (severe) with an additional quality of life (QOL) index scored from 0 (satisfied) to 3 (extremely dissatisfied). Statistical analysis was made using Student's t test. Compared with the control subjects, the frequency of LUTSs in the MG patients was significantly higher for daytime frequency (43%; p < 0.01), nocturia (24%; p < 0.01), and urinary incontinence (43%; p < 0.05). The LUTS-related QOL index for the MG patients was significantly higher for MG patients as a whole than that for all control patients (29%) (p < 0.05). In conclusion, our study results showed that MG patients had significantly more LUTSs (overactive bladder) than healthy control subjects and had worse LUTS-related QOL; therefore, amelioration of LUTS in MG is important.