Phenotyping chronic pelvic pain based on latent class modeling of physical examination

Pain Phenotypes in Endometriosis: A Population-Based Study Using Latent Class Analysis

OBJECTIVE

To identify pain phenotypes in patients with endometriosis and investigate their associations with demographics, clinical characteristics, comorbidities and pain-related quality of life (QoL).

DESIGN

Cross-sectional, single-centre, population-based study.

SETTING

Referral university centre in Quebec City, Canada.

POPULATION

Patients diagnosed with endometriosis were enrolled consecutively between January 2020 and April 2024.

METHODS

Latent class analysis was used to identify pain phenotypes. A three-step approach of latent class analysis, involving logistic regression models, was applied to assess the associations between pain phenotypes and demographics, clinical characteristics, comorbidities and pain-related QoL.

MAIN OUTCOME MEASURES

Pain phenotypes; demographic, clinical and comorbidity predictors of phenotype membership; association between QoL and pain phenotypes.

RESULTS

A total of 352 patients were included. Two pain phenotypes were identified with distinct clinical presentations: one (54% of the participants) with more severe and frequent pain symptoms and poorer QoL and the other (46% of the participants) with mild and less frequent pain symptoms. The high pain phenotype was associated with previous treatment failure, painkiller use, familial history of endometriosis, low annual family income and comorbidities, including painful bladder, fibromyalgia, migraines, lower back pain, irritable bowel syndrome, anxiety and depression or mood disorders. The presence of endometrioma was associated with the low pain phenotype. Phenotype membership was associated with distinct QoL profiles (p < 0.001). The mean QoL score was higher in the high pain phenotype (59; 95% CI, 56-62) than in the low pain phenotype (33; 95% CI, 29-37).

CONCLUSION

Patients with endometriosis can be categorised into two distinct phenotypes that correlate with QoL and patient characteristics. Validation in other populations is necessary and could aid the development of specialised or personalised interventions.

Using PROMIS® to create clinically meaningful profiles of nephrotic syndrome patients

OBJECTIVE

Nephrotic syndrome (NS) is a kidney disease known to adversely impact health-related quality of life (HRQOL). Patient-reported outcome (PRO) measures are commonly used to characterize HRQOL and the patient disease experience. This study aims to improve the interpretability and clinical utility of the Patient-Reported Outcomes Measurement Information System® (PROMIS®) by identifying distinct meaningful HRQOL profiles in children and adults with NS.

METHOD

Patients were from 2 prospective NS cohort studies (PROMIS-II®: 121 children; NEPTUNE: 40 children and 219 adults) with data from 6 PROMIS® domains. Latent Profile Analysis was used to identify subgroups of patients based on PROMIS® score patterns. A 3-step analysis of latent profile predictors was used to determine how clinical parameters predicted HRQOL profile membership.

RESULTS

We identified 3 HRQOL profiles (Good, Average, and Poor) with strong indicators of membership classification (entropy >0.86). Complete proteinuria remission, reduction in symptoms, and shorter disease duration, were significant predictors of better HRQOL profile membership.

CONCLUSIONS

Patients with NS can be classified by HRQOL into clinically meaningful categories. Integrating this approach into clinic may help in the identification of individuals with poor HRQOL will help clinicians better manage their symptoms and researchers study the causes and possible interventions for these patients. PROMIS® HRQOL profiles were reproducible in replication cohorts. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Physical examination techniques for the assessment of pelvic floor myofascial pain: a systematic review

BACKGROUND

Myofascial pain is characterized by the presence of trigger points, tenderness to palpation, and local or referred pain, and commonly involves the pelvic floor muscles in men and women. Pelvic floor myofascial pain in the absence of local or referred pain has also been observed in patients with lower urinary tract symptoms, and we have found that many patients report an improvement in these symptoms after receiving myofascial-targeted pelvic floor physical therapy.

OBJECTIVE

We sought to systematically review the literature for examination techniques used to assess pelvic floor myofascial pain in women.

STUDY DESIGN

We performed a systematic literature search using strategies for the concepts of pelvic floor disorders, myofascial pain, and diagnosis in Ovid MEDLINE 1946-, Embase 1947-, Scopus 1960-, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, and Cochrane Database of Systematic Reviews. Articles were screened by 3 authors and included if they contained a description of a pelvic myofascial physical examination.

RESULTS

In all, 55 studies met our inclusion criteria. Overall, examination components varied significantly among the included studies and were frequently undefined. A consensus examination guideline was developed based on the available data and includes use of a single digit (62%, 34/55) to perform transvaginal palpation (75%, 41/55) of the levator ani (87%, 48/55) and obturator internus (45%, 25/55) muscles with a patient-reported scale to assess the level of pain to palpation (51%, 28/55).

CONCLUSION

Physical examination methods to evaluate pelvic musculature for presence of myofascial pain varied significantly and were often undefined. Given the known role of pelvic floor myofascial pain in chronic pelvic pain and link between pelvic floor myofascial pain and lower urinary tract symptoms, physicians should be trained to evaluate for pelvic floor myofascial pain as part of their physical examination in patients presenting with these symptoms. Therefore, the development and standardization of a reliable and reproducible examination is needed.

Classifying Patients with Chronic Pelvic Pain into Levels of Biopsychosocial Dysfunction Using Latent Class Modeling of Patient Reported Outcome Measures

Chronic pelvic pain affects multiple aspects of a patient's physical, social, and emotional functioning. Latent class analysis (LCA) of Patient Reported Outcome Measures Information System (PROMIS) domains has the potential to improve clinical insight into these patients' pain. Based on the 11 PROMIS domains applied to n=613 patients referred for evaluation in a chronic pelvic pain specialty center, exploratory factor analysis (EFA) was used to identify unidimensional superdomains. Latent profile analysis (LPA) was performed to identify the number of homogeneous classes present and to further define the pain classification system. The EFA combined the 11 PROMIS domains into four unidimensional superdomains of biopsychosocial dysfunction: Pain, Negative Affect, Fatigue, and Social Function. Based on multiple fit criteria, a latent class model revealed four distinct classes of CPP: No dysfunction (3.2%); Low Dysfunction (17.8%); Moderate Dysfunction (53.2%); and High Dysfunction (25.8%). This study is the first description of a novel approach to the complex disease process such as chronic pelvic pain and was validated by demographic, medical, and psychosocial variables. In addition to an essentially normal class, three classes of increasing biopsychosocial dysfunction were identified. The LCA approach has the potential for application to other complex multifactorial disease processes.