Yeh HL, et al. - Subjects with interstitial cystitis/bladder pain syndrome (IC/BPS), a chronic disease, which is difficult to treat, with a history of >5 years and who had comprehensive medical records, baseline IC symptom index and IC problem index, O'Leary-Sant symptom score, and visual analog scale were recruited in this study by the experts in order to examine long-term symptom alterations in subjects with IC/BPS, particularly in those who were lost to follow-up. A total of 198 subjects with IC/BPS were involved. At a mean follow-up term of 16.6 ± 9.75 years, 12% and 47% of the subjects were free of symptoms and manifested symptom improvement of more than 50%, respectively. In total, 47 and 151 subjects were lost to follow-up for >5 years and had a regular follow-up, respectively. In comparison to those who had a regular follow-up, cases with IC/BPS who were not routinely followed up had no Hunner's lesion and had a higher bladder volume, higher urine flow, and lesser comorbidities. In the subjects who were lost to follow-up, the number of treatment modalities was significantly fewer. Hence, about half of the cases with IC/BPS demonstrated symptom betterment respective to time, with or without regular follow-up and receiving a new treatment.