Symptom Variability and Early Symptom Regression in the MAPP Study: A Prospective Study of Urological Chronic Pelvic Pain Syndrome

Abstract

Introduction We examine symptom variability in men and women with urological chronic pelvic pain syndrome (UCPPS). We describe symptom fluctuations as related to early symptom regression and its effect on estimated one-year symptom change. We then describe a method to quantify patient-specific symptom variability. Methods Symptoms were assessed biweekly in 424 UCPPS subjects over one year. Subjects were classified as ‘improved’, ‘no change’, or ‘worse’ according to their rate of change using 1) all data, 2) excluding week 0, and 3) excluding weeks 0 and 2 to evaluate the impact of early symptom regression. Patient-specific time-varying variability was calculated at each interval using a sliding window approach. Patients were classified as high, medium, or low variability at each time and ultimately as high or low variability overall based on their variability for the majority of contacts. Results Prior to excluding early weeks to adjust for early symptom regression 25–38% and 5–6% of patients were classified as improved and worse, respectively; after adjustment the percentage of patients improved or worse ranged from 15–25% and 6–9%. ‘High and ‘low’ variability phenotypes were each identified in 25–30% of participants. Conclusions Patients with UCPPS exhibit symptom variability. At enrollment, patients had, on average, worse symptoms, resulting in a regression effect that influenced the estimated proportion of improved or worse subjects. Prospective studies should include a run-in to account for regression to the mean and other causes of early symptom regression. Further, symptom variability may be quantified and used to characterize longitudinal UCPPS symptom profiles.

Clinical and Psychosocial Predictors of Urological Chronic Pelvic Pain Symptom Change in 1 Year: A Prospective Study from the MAPP Research Network

“…21 This may be due to enrollment bias, i.e. participants seek out studies when symptoms are relatively elevated so declines in the following weeks are expected due to the pattern of normal symptom fluctuation, or to study-related expectation/placebo effects even if no specific treatments are involved.…”

“…13 A functional clustering procedure was applied to the biweekly pain and urinary severity scores to classify the overall symptom trajectory for each participant as worsening, stable or improving over the study period (for details see Supplemental Appendix C). To decrease the influence of study entry effects on outcome classification the first month of symptom ratings were not used in the clustering algorithm 14 and the symptom ratings at study week 4 were used as the baseline symptom level for the modeling. Figure 1 shows individual symptom trajectories by cluster, overlaid by the average symptom trajectory within the cluster.…”

Interstitial Cystitis-Associated Urinary Metabolites Identified by Mass-Spectrometry Based Metabolomics Analysis

“…Nonetheless, we still lack definite criteria for the disease. Estimates of the prevalence and natural history of IC still fluctuate widely because of different diagnostic standards, populations evaluated, and challenges inherent in following patients over time6. Thus, the identification of sensitive and non-invasive biomarkers has the potential to greatly improve the accuracy of an IC diagnosis.…”

Correlates of Health Care Seeking Activities in Patients with Urological Chronic Pelvic Pain Syndromes: Findings from the MAPP Cohort

“…Participants underwent an in-depth baseline evaluation; to account for regression to the mean, we employed a 4-week run-in period so that week 4 data were defined as baseline values for analytic purposes 8 . Less comprehensive assessments were performed at the 6- and 12-month follow-up visits 7 .…”

“…Separate scores for UCPPS pain severity and urinary severity were obtained from biweekly responses to the Genitourinary Pain Index 9 and the Interstitial Cystitis Symptom index 10 as reported previously 11 . At the time of each biweekly assessment, the within-person pain and urologic symptom variability was determined based on the standard deviation of pain scores and urinary scores, respectively, for the preceding 6-week time period 8 .…”