Risk Classification for Interstitial Cystitis/Bladder Pain Syndrome Using Machine Learning Based Predictions

OBJECTIVE

To improve diagnosis of interstitial cystitis (IC)/bladder pain syndrome(IC) we hereby developed an improved IC risk classification using machine learning algorithms.

METHODS

A national crowdsourcing resulted in 1264 urine samples consisting of 536 IC (513 female, 21 male, 2 unspecified), and 728 age-matched controls (318 female, 402 male, 8 unspecified) with corresponding patient-reported outcome (PRO) pain and symptom scores. In addition, 296 urine samples were collected at three academic centers: 78 IC (71 female, 7 male) and 218 controls (148 female, 68 male, 2 unspecified). Urinary cytokine biomarker levels were determined using Luminex assay. A machine learning predictive classification model, termed the Interstitial Cystitis Personalized Inflammation Symptom (IC-PIS) Score, that utilizes PRO and cytokine levels, was generated and compared to a challenger model.

RESULTS

The top-performing model using biomarker measurements and PROs (area under the curve [AUC]=0.87) was a support vector classifier, which scored better at predicting IC than PROs alone (AUC=0.83). While biomarkers alone (AUC=0.58) did not exhibit strong predictive performance, their combination with PROs produced an improved predictive effect.

CONCLUSION

IC-PIS represents a novel classification model designed to enhance the diagnostic accuracy of IC/bladder pain syndrome by integrating PROs and urine biomarkers. The innovative approach to sample collection logistics, coupled with one of the largest crowdsourced biomarker development studies utilizing ambient shipping methods across the US, underscores the robustness and scalability of our findings.

Evaluating symptom severity and urinary cytokine levels in interstitial cystitis/bladder pain syndrome patients, with and without Hunner's lesions

PURPOSE

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a condition characterized in part by urinary urgency, frequency, and pain. There is a strong interest in gathering more data to compare and assess the differences in characteristics based on the presence of Hunner's lesions in patients with IC/BPS.

MATERIALS AND METHODS

Using a nationwide crowdsource effort, we collected surveys and urine samples from patients with a history of IC/BPS. Participants completed the Interstitial Cystitis Symptom Index (ICSI) and Problem Index (ICPI), Overactive Bladder questionnaire (OABq SF), and pain scores. In addition, participants reported any co-morbidities and lifestyle modifications. Urinary cytokine levels were measured and compared to symptom severity.

RESULTS

491 participants enrolled: 119 with history of ulcerative Hunner's lesions (UIC), 372 reported no lesions (NHIC), and 2 unknowns. 96.3% were female, and prevalence of UIC was equal for both genders. Average age was higher for UIC vs. NHIC group (P = 0.011), as was the duration since diagnosis (P < 0.001). Symptom scores were elevated in UIC patients (P < 0.001). Both groups widely implemented lifestyle modifications, with dietary changes being most prevalent (70.1%), followed by prescription medication usage (63.1%). More UIC compared to NHIC participants experienced co-morbidities (P = 0.010). Urine samples were analyzed for GRO, IL-6, IL-8, and MCP-1. MCP-1 levels were significantly higher in UIC patients (P = 0.044). Weak positive correlation was found between cytokines and symptom scores.

CONCLUSIONS

Patients with UIC and NHIC from across the United States displayed distinct phenotypic and urine biological characteristics. These findings contribute to increased understanding of IC/BPS and may aid in improving our knowledge of the condition.

Identification of Molecular Mechanisms in Radiation Cystitis: Insights from RNA Sequencing

Pelvic cancer survivors who were treated with radiation therapy are at risk for developing (hemorrhagic) radiation cystitis (RC) many years after completion of radiation therapy. Patients with RC suffer from lower urinary tract symptoms, including frequency, nocturia, pelvic pain, and incontinence. In advanced stages, hematuria can occur, potentially escalating to life-threatening levels. Current therapeutic options for RC are limited, partly due to ethical concerns regarding bladder biopsy in patients with fragile bladder tissue. This study aimed to leverage our established preclinical model to elucidate the molecular pathways implicated in radiation-induced tissue changes in the bladder. Female C57Bl/6 mice received a single dose of 40 Gy using CT-guided imaging and a two-beam irradiation approach using the SARRP irradiator. Bladders from irradiated and age-matched littermate controls were harvested at 1 week [n = 5/group] or 6 months [n = 5/group] after irradiation, RNA was harvested, and mRNA sequencing was performed at paired-end 150bp on the Illumina NovaSeq6000 with a target of 30 million reads per sample. Following RNA sequencing, thorough bioinformatics analysis was performed using iPathwayGuide v2012 (ADVAITA Bioinformatics). Findings of the RNA sequencing were validated using qPCR analysis. At 1 week post-irradiation, altered gene expression was detected in genes involved in DNA damage response, apoptosis, and transcriptional regulation. By 6 months post-irradiation, significant changes in gene expression were observed in inflammation, collagen catabolism, and vascular health. Affected pathways included the p53, JAK-STAT, and PI3K-Akt pathways. These findings were validated in vivo in bladder tissues from our preclinical model. This is the first study to determine the molecular changes in the bladder in response to radiation treatment. We have successfully pinpointed several pathways and specific genes that undergo modification, thereby contributing to the progression of radiation cystitis. These insights enhance our understanding of the pathophysiology of radiation cystitis and may ultimately pave the way to the identification of potential new therapeutic targets.

Comparing online crowdsourcing with clinic patient enrollment: Findings from the IP4IC Study on interstitial cystitis/bladder pain syndrome

Introduction

Interstitial cystitis/bladder pain syndrome (IC/BPS) manifests as urinary symptoms including urgency, frequency, and pain. The IP4IC Study aimed to establish a urine-based biomarker score for diagnosing IC/BPS. To accomplish this objective, we investigated the parallels and variances between patients enrolled via physician/hospital clinics and those recruited through online crowdsourcing.

Methods

Through a nationwide crowdsource effort, we collected surveys from patients with history of IC/BPS. Study participants were asked to complete the validated instruments of Interstitial Cystitis Symptom Index (ICSI) and Interstitial Cystitis Problem Index (ICPI), as well as provide demographic information. We then compared the survey responses of patients recruited through crowdsourcing with those recruited from three specialized tertiary care urology clinics engaged in clinical research.

Results

Survey responses of 1300 participants were collected from all 50 states of the USA via crowdsourcing and 319 from a clinical setting. ICSI and ICPI were similar for IC/BPS patients diagnosed by the physicians in clinic and self-reported by subjects via crowdsourcing stating they have a history of previous physician diagnosis of IC/BPS. Surprisingly, ICSI and ICPI were significantly lower in crowdsourced control than in-clinic control subjects.

Conclusion

The IP4IC Study provides valuable insights into the similarities and differences between patients recruited through clinics and those recruited through online crowdsourcing. There were no significant differences in disease symptoms among these groups. Individuals who express an interest in digital health research and self-identify as having been previously diagnosed by physicians with IC/BPS can be regarded as reliable candidates for crowdsourcing research.

A Cost, Time, and Demographic Analysis of Participant Recruitment and Urine Sample Collection Through Social Media Optimization

INTRODUCTION

Clinical research can be expensive and time consuming due to high associated costs and/or duration of the study. We hypothesized that urine sample collection using online recruitment and engagement of research participants via social medial has the potential to reach a large population in a small timeframe, at a reasonable cost.

METHODS

We performed a retrospective cost analysis of a cohort study comparing cost per sample and time per sample for both online and clinically recruited participants for urine sample collection. During this time, cost data were collected based on study associated costs from invoices and budget spreadsheets. The data were subsequently analyzed using descriptive statistics.

RESULTS

Each sample collection kit contained 3 urine cups, 1 for the disease sample and 2 for control samples. Out of the 3,576 (1,192 disease + 2,384 control) total sample cups mailed, 1,254 (695 control) samples were returned. Comparatively, the 2 clinical sites collected 305 samples. Although the initial startup cost of online recruitment was higher, cost per sample for online recruited was found to be $81.45 compared to $398.14 for clinic sample.

CONCLUSIONS

We conducted a nationwide, contactless, urine sample collection through online recruitment in the midst of the COVID-19 pandemic. Results were compared with the samples collected in the clinical setting. Online recruitment can be utilized to collect urine samples rapidly, efficiently, and at a cost per sample that was 20% of an in-person clinic, and without risk of COVID-19 exposure.

Using social media to crowdsource collection of urine samples during a national pandemic

The COVID-19 pandemic and subsequent lockdown had a substantial impact on normal research operations. Researchers needed to adapt their methods to engage at-home participants. One method is crowdsourcing, in which researchers use social media to recruit participants, gather data, and collect samples. We utilized this method to develop a diagnostic test for Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS). Participants were recruited via posts on popular social-media platforms, and enrolled via a website. Participants received and returned a mail kit containing bladder symptom surveys and a urine sample cup containing room-temperature preservative. Using this method, we collected 1254 IC/BPS and control samples in 3 months from all 50 United States. Our data demonstrate that crowdsourcing is a viable alternative to traditional research, with the ability to reach a broad patient population rapidly. Crowdsourcing is a powerful tool for at-home participation in research, particularly during the lockdown caused by the COVID-19 pandemic.

Proteomic analysis of bladder biopsies from interstitial cystitis/bladder pain syndrome patients with and without Hunner's lesions reveals differences in expression of inflammatory and structural proteins

Background

Interstitial cystitis/bladder pain syndrome is a bladder disease usually characterized by pain, urgency, and frequency. Interstitial cystitis is currently classified into two subtypes, with and without Hunner’s lesions. However, the underlying etiology of interstitial cystitis and its subtypes are largely unknown.

Methods

To better understand the biological changes in the bladder of interstitial cystitis/bladder pain syndrome patients, we directly analyzed bladder tissue of interstitial cystitis patients, both those with Hunner’s lesions and those without. Proteins in the bladder biopsies were analyzed using nanoscale high-performance liquid chromatography-tandem mass spectrometry. Disease subgroups were compared and significantly expressed proteins were mapped using STRING to determine protein associations and functions.

Results

We found that patients with Hunner’s lesions had significant increases in inflammatory and endoplasmic reticulum stress proteins, with a decrease in cellular adhesive proteins, compared to patients without Hunner’s lesions. These patients also exhibited a decrease in proteins associated with the Rap1 signaling pathway, which regulates cell proliferation and wound healing. When comparing diseased and non-disease-apparent tissue in patients with Hunner’s lesions, diseased tissue exhibited a decrease in ubiquitination proteins.

Conclusions

In summary, there are significant differences in protein expression found in the bladders of interstitial cystitis patients with and without Hunner’s lesions, indicating a disturbance in proteins associated with cellular adhesion, proliferation, protein processing, and wound healing.

Micturition defects and altered bladder function in the klotho mutant mouse model of aging

INTRODUCTION AND OBJECTIVES

Symptoms associated with detrusor underactivity (DU) or underactive bladder (UAB) can severely impact a person's quality of life, and growing old is the main etiological factor of DU and UAB. The gene Klotho has been associated with suppression of several aging phenotypes, and there is moderate klotho expression in the bladder. Given this, we hypothesized that the klotho gene is involved in regulation of bladder function. Thus, we examined a premature aging rodent genetic model with hypomorphic klotho expression for alterations in bladder function.

METHODS

Klotho mutant mice are established as a preclinical model of aging. Male and female klotho mice had micturition measured at weeks 4, 6, and 8 through metabolic cage and void spot assays. Histology was assessed at 4, 6, and 8 weeks. Lastly, bladder contraction was assessed using bladder strip tissue bath. All animals were gender- and age-matched with wild-type littermates for analysis.

RESULTS

Void spot and bladder contraction assays revealed that klotho mutant mice, similar to other aging models, have increased voiding frequency and decreased voiding volume per micturition event. The in vitro contractile response to electrical stimulation was weaker and muscarinic receptor subtype expression was reduced in the in klotho mutant mouse bladders. These data suggest that klotho mutant mouse bladders had impaired bladder function.

CONCLUSIONS

Klotho mutant mice recapitulate many characteristics of an older dysfunctional bladder, including altered bladder function. Given the short time frame to bladder dysfunction and robustness of the model, this model will provide new insights to drive aging bladder research.

Abstract P4-17-06: First posts: A content analysis of an online breast cancer community user's initial postings

Introduction: Online breast cancer communities provide users with both information and emotional support. Members of these communities include both patients and caregivers. We aimed to characterize the differences in content between patients' and caregivers' first posts.

Methods: 20189 posts were downloaded from a public online breast cancer community. Posts were sorted by user name and date to identify unique posters and coded for user demographics and content. Descriptive statistics (e.g. chi-square test) characterized differences between patients and caregivers in terms of topics and content.

Results: Of the 1827 unique posters, 83% were identified as the patient (n=1277, 70%) and 13% were identified as a caregiver (n=230). 835 (69%) patients had been previously diagnosed with breast cancer. Chemotherapy was the most common topic among cancer patients. Patients tended to seek information about physical concerns more often than psychosocial concerns. In contrast, caregivers used the community significantly more often as a source of emotional support (p&lt;.001), although they also sought information on how to best support patients.

Breast Cancer Patients' Topics of ConversationTopicN(%)ExplanationExampleChemotherapy296 (36)Patients discussing the decision for chemotherapy, or their experiences with it.“I was allergic to some of the chemo meds”Radiation255 (31)Patients discussing the decision for radiation, or their experiences with it.“I wanted to answer your query about radiation…”Estrogen Modulating Therapy156 (19)Patients discussing the decision to take estrogen modulating medications (e.g. Tamoxifen) or their experiences with it.“I don't know if I'm going to take this with all the side effects I read.”Surgery55 (7)Patients discussing surgical options for breast cancer treatment (not reconstruction) or experiences with the procedures.“I don't want them to leave half of my breast with a chance for a new diagnosis”Reconstruction49 (6)Patients discussing reconstruction options or experiences with the procedures.“I recently had a TE recon and it went fine but a week later i developed an infection…”

Thematic Content of Posts: Patients v. CaregiversDomainPatients n(%)Caregivers n(%)Chi-Square p-valueExplanationExampleDiscussing Physical Issues234 (29)25 (11)&lt;.001Discussing physical symptoms as a result of cancer or treatment.“I was allergic to some of the chemo meds”Seeking Emotional Support113 (14)34 (15)&lt;.001Poster discusses feeling upset, or directly asks for support.“Thanks for listening to my pity party...”Discussing Psychosocial Issues89 (11)21 (9).165Poster mentions psychological issues including depression or anxiety, or with social sequelae of cancer such as marital difficulties.“I also found help through the use of an antidepressant…I feel like a fog has lifted.”

Conclusion: First post content varied depending on if the poster was a patient or a caregiver. Patients' first posts were often information-seeking about physical concerns, whereas caregivers tended to use the forum as a source of emotional support. By analyzing the frequency of topics and content of posts, clinicians may better understand the educational needs of patients and caregivers.

Citation Format: Marmor RA, Ward EP, Epstein E, Reghunathan M, Schoenbrunner A, Unkart JT, Blair SL, Huh J. First posts: A content analysis of an online breast cancer community user's initial postings [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-17-06.

Enhancing the representation of rural areas in the National Medical Expenditure Survey

This study examines the issues associated with enhancing the representation of rural areas in the National Medical Expenditure Survey (NMES). It reviews alternative definitions of rural areas and describes the classification schemes considered for future cycles of the NMES. A review of the NMES sample representation in rural areas and an examination of the analytical capabilities and limitations of the current design for deriving health care estimates of the rural population is provided. The options presented in this article would extend the analytical capacity of the NMES to permit estimates of rural areas of the national classified by census region, by gradations of rural classification, and for individuals residing in rural frontier counties.