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.