Hypothesis / aims of study
Interstitial cystitis (IC) and bladder pain syndrome (BPS) are relatively rare diseases and cause uncomfortable feelings and pain around pelvis such as the bladder, lower abdomen, prostate, testis, and penis. In addition, patients with IC/BPS often have lower urinary tract symptoms (LUTS). It was reported that the most serious problem for them was pelvic discomfort and pain. Psychological distress due to the symptoms impairs their quality of life, however the pathophysiology of IC/BPS has remained still unclear, and a revolutionary therapeutic strategy has not been developed.
It was reported that physical and mental stress would be involved in worsening the symptoms of IC/BPS. Thus, we examined the relationship between degree of IC/BPS symptoms and stress factors of patients with IC/BPS.
Study design, materials and methods
The analysis of clinical data was approved by the Ethics Committee of the Faculty of Medical Sciences, University of Fukui, and informed consent was performed on all patients. 82 IC/BPS patients who visited our institution from January 2001 to December 2022 were enrolled in the study. We evaluated the degree of patients’ symptoms by the Oleary-sant symptom index (OSSI) and problem index (OSPI) at the point of first visit and of after treatment, and we also used the numerical rating scale (NRS), which is used for the evaluation of patients’ pain. Patients scored the degree of their current pain from 0 to 10, 10 means the pain which is the most severe they can imagine in their life, whereas 0 means no pain.
The stress factors of patients were defined as divorce, bereavement, history of mental illness and cancer in the present study. We performed the treatment for IC/BPS as hydraulic dilatation, administration of IPD capsule, or injection of DMSO in their bladder.
We retrospectively assessed whether the history of stress events was related to the OSSI/OPSI scores at first visit and after treatment, and also evaluated the effectiveness of IC/BPS treatment between the group with stress (stressor) and that without stress (non-stressor).
We evaluated the effect of stress on OSSI, OSPI, duration of response, and pain scale before and after the start of treatment using by t-test analysis. All statistical analyses were carried out using EZR, and p-values <0.05 were considered significant.
Results
We observed that 77 cases of 82 total cases. Five cases were excluded due to insufficient information. Sixteen cases were IC with Hunner lesions, 55 cases were BPS, and 6 cases were other types. Thirty-eight of the patients had stressors, 31 had non-stressors, and 8 were undecidable.
The score of NRS of pretreatment were significantly higher in the group of stressor than in the group of non-stressor (6.65±2.90 vs. 4.14±3.53, p=0.017, Fig. 1). There was no significant difference in NRS score posttreatment between both groups, however the gap of pain severity between before and after treatment was significantly higher in the group of patients with stressors (-5.77±3.59 vs. -2,16±3.56, p=0.033, Fig. 2).
In the OSSI and OSPI, the difference between pre-treatment and post-treatment in OSPI question 1 (urinary urgency) was significantly higher in the group of patients with stressors (-1.91±1.16 vs. -0.82±1.38, p=0.033).
In other items of OSSI and OPSI, there were no significant differences between these groups.
Interpretation of results
The present study indicated that psychological stress would be the factor that exacerbated the degree of pain in patients with IC/BPS, whereas the stress would hardly influence LUTS, except for the urinary urgency. The treatment for IC/BPS was more effective in patients with a history of stress, and finally the degree of their symptoms after the treatment was almost the same nevertheless the existence of psychological stress.