Naturalistic Bladder Filling Reveals Subtypes in Overactive Bladder Syndrome That Differentially Engages Urinary Urgency-Related Brain Circuits: Results From the Symptoms of Lower Urinary Tract Dysfunction Research Network (LURN).

PURPOSE: Overactive bladder (OAB) may be attributed to dysfunction in supraspinal brain circuits. Overactive bladder participants enrolled in the LURN (Symptoms of Lower Urinary Tract Dysfunction Research Network) study reported sensations of urinary urgency during a bladder-filling paradigm while undergoing brain functional MRI to map supraspinal dysfunction. MATERIALS AND METHODS: OAB participants and controls (CONs) completed 2 resting-state functional MRI scans following consumption of 350 mL water. Scans were conducted at fuller and emptier bladder states, interleaved with voiding. Urgency ratings (0-10) were assessed. Patterns of urgency during bladder filling were investigated using latent class trajectory models. Clusters of participants encompassing each pattern (ie, subtype) were derived from aggregated groups of OAB and CON independent of diagnosis. RESULTS: Two distinct patterns of urgency trajectories were revealed: first subtype with OAB and CON who were unresponsive to bladder filling (OAB-1 and CON-1) and second highly responsive subtype predominantly containing OAB (OAB-2). OAB-2 participants scored significantly higher on urinary symptoms but not pain or psychosocial measures. Neuroimaging analyses showed change in urgency due to both bladder filling and voided volume related to multiple loci of brain network connectivity in OAB-2, and in some cases, different than OAB-1 and/or CON-1. Sensorimotor to dorsomedial/dorsolateral prefrontal connectivity mediated the relationship between stimulus (voided volume) and percept (urgency) in OAB-2. CONCLUSIONS: Our results reveal different OAB subtypes with latent class trajectory models of urgency ratings during natural bladder filling. Functional MRI revealed differences in pathophysiology between subtypes, namely sensorimotor-prefrontal connectivity is a key locus in OAB patients with higher urinary symptoms.

Longitudinal changes in symptom-based female and male LUTS clusters.

AIMS: Lower urinary tract symptoms (LUTS) are diverse in type and variable in severity. We examined symptom change within the Symptoms of the Lower Urinary Tract Dysfunction Research Network (LURN) Observational Cohort study identified clusters over time and tested associations with treatments received. METHODS: Patient-reported LUTS and treatment data were collected at multiple time points between baseline and 12 months from the LURN Observational Cohort study. LUTS severity scores were calculated to summarize changes in symptom reporting over time in previously identified LURN clusters. Repeated measures linear regression models tested adjusted associations between cluster membership and severity scores. RESULTS: Four-hundred seventeen men and 396 women were classified into improved, unchanged, and worsened symptoms between baseline and 12 months (men: 44.1%, 40.5%, and 15.3%; women: 55.8%, 33.1%, 11.1%, respectively). Improvement in LUTS severity scores varied by cluster (estimated adjusted mean change from baseline range: -.04 change in standard deviations of severity scores (ΔSD) to -.67 ΔSD). Prostate surgery was associated with improved severity scores (-.63 ΔSD) in men, while stress incontinence surgery was associated with improved severity scores (-.88 ΔSD) in women. CONCLUSION: Symptom improvement varied by cluster indicating response to therapy differs amongst subtypes of patients with LUTS. The differential improvement of patients in clusters suggests mechanistic differences between clusters and may aid in selecting more targeted treatments in the future.

Accelerated coronary atherosclerosis not explained by traditional risk factors in 13% of young individuals.

IMPORTANCE: Most individuals who die of sudden cardiac death (SCD) display very advanced lesions of atherosclerosis in their coronary arteries. Thus, we sought to identify and characterize a putative subpopulation of young individuals exhibiting accelerated coronary artery atherosclerosis. OBJECTIVE: Our analysis of the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) study-which examined 2651 individuals, obtaining quantitative measurements of traditional risk factors for coronary heart disease (CHD)-aimed to identify individuals with advanced coronary artery lesions, and to determine whether risk factors could account for such rapid disease progression, or not. DESIGN: Using the cross-sectional PDAY study data, an exploratory de facto analysis stratified the population by age and observed number of coronary raised lesions and examined these groups via Poisson regression modeling. A separate de novo approach utilized Poisson mixture modeling to generate low- and high-growth groups based on measurements of traditional risk factors, and identified factors contributing to disease progression. PARTICIPANTS: Participants, n = 2651 individuals aged 15-34, who had died of non-cardiac death, were recruited post mortem. Tissues and other samples were harvested for analysis (details in previously published PDAY studies). Main Outcome(s) and Measure(s). Using quantitative measurements of raised coronary lesions and traditional risk factors of CHD, we sought to identify which risk factors account for disease progression. RESULTS: A group of ~13% of the PDAY population exhibits accelerated coronary atherosclerosis despite their young age. Several traditional risk factors were associated with increased odds of inclusion in this subgroup, reflecting current understanding of these markers of disease. However, only age was a significant contributing factor to the observed coronary lesion burden. CONCLUSIONS: While a range of traditional risk factors contribute to an individual's inclusion to the identified subgroup with accelerated atherosclerosis, these factors, with the exceptions of age, are not able to predict an individual's lesion burden. Moreover, unattributed variances in observations indicate the need to study novel risk factors. SHORT SUMMARY: Hypothesis The extent of coronary atherosclerotic disease is limited and homogeneous within youth, and its progression can be accounted for by traditional risk factors in this population. FINDINGS: A subpopulation (~13%) of the Pathobiological Determinants of Atherosclerosis in Youth cohort exhibited accelerated coronary artery atherosclerosis. While several traditional risk factors contribute to an individual's inclusion in this subgroup, these factors, with the exceptions of age, do not predict accurately an individual's lesions burden. Critically, unattributed variances in observations indicate the need for the identification of novel risk factors. MEANING: Screening of the general population at a young age for high-risk group membership could provide opportunity for disease prevention and avoidance of the worse complications such as myocardial infarction and sudden cardiac death later in life.

Biomarkers Implicated in Lower Urinary Tract Symptoms: Systematic Review and Pathway Analyses.

PURPOSE: Lower urinary tract symptoms are prevalent and burdensome, yet methods to enhance diagnosis and appropriately guide therapies are lacking. We systematically reviewed the literature for human studies of biomarkers associated with lower urinary tract symptoms. MATERIALS AND METHODS: PubMed®, EMBASE® and Web of Science® were searched from inception to February 13, 2018. Articles were included if they were in English, performed in benign urological populations without neurological disorders or interstitial cystitis/bladder pain syndrome, and assessed a biomarker's association with or ability to predict specific lower urinary tract symptoms or urological conditions. Bioinformatic pathway analyses were conducted to determine whether individual biomarkers associated with symptoms are present in unifying pathways. RESULTS: Of 6,150 citations identified 125 met the inclusion criteria. Most studies (93.6%) assessed biomarkers at 1 time point and were cross-sectional in nature. Few studies adjusted for potentially confounding clinical variables or assessed biomarkers in an individual over time. No individual biomarkers are currently validated as diagnostic tools for lower urinary tract symptoms. Compared to controls, pathway analyses identified multiple immune response pathways that were enriched in overactive bladder syndrome and cell migration/cytoskeleton remodeling pathways that were enriched in female stress incontinence. CONCLUSIONS: Major deficiencies in the existing biomarker literature include poor reproducibility of laboratory data, unclear classification of patients with lower urinary tract symptoms and lack of adjustment for clinical covariates. Despite these limitations we identified multiple putative pathways in which panels of biological markers need further research.

Symptom Based Clustering of Men in the LURN Observational Cohort Study.

PURPOSE: Conventional classification of patients with lower urinary tract symptoms into diagnostic categories based on a predefined symptom complex or predominant symptom appears inadequate. This is due to the frequent presentation of patients with multiple urinary symptoms which could not be perfectly categorized into traditional diagnostic groups. We used a novel clustering method to identify subtypes of male patients with lower urinary tract symptoms based on detailed multisymptom information. MATERIALS AND METHODS: We analyzed baseline data on 503 care seeking men in the LURN (Symptoms of Lower Urinary Tract Dysfunction Research Network) Observational Cohort Study. Symptoms and symptom severity were assessed using the LUTS (Lower Urinary Tract Symptoms) Tool and the AUA SI (American Urological Association Symptom Index), which include a total of 52 questions. We used a resampling based consensus clustering algorithm to identify patient subtypes with distinct symptom signatures. RESULTS: Four distinct symptom clusters were identified. The 166 patients in cluster M1 had predominant symptoms of frequency, nocturia, hesitancy, straining, weak stream, intermittency and incomplete bladder emptying suggestive of bladder outlet obstruction. The 93 patients in cluster M2 mainly endorsed post-micturition symptoms (eg post-void dribbling and post-void leakage) with some weak stream. The 114 patients in cluster M3 reported mostly urinary frequency without incontinence. The 130 patients in cluster M4 reported severe frequency, urgency and urgency incontinence. Most other urinary symptoms statistically differed between cluster pairs. Patient reported outcomes of bowel symptoms, mental health, sleep dysfunction, erectile function and urological pain significantly differed across the clusters. CONCLUSIONS: We identified 4 data derived clusters among men seeking care for lower urinary tract symptoms. The clusters differed from traditional diagnostic categories. Further subtype refinement will be done to incorporate clinical data and nonurinary patient reported outcomes.

The Comprehensive Assessment of Self-Reported Urinary Symptoms: A New Tool for Research on Subtypes of Patients with Lower Urinary Tract Symptoms.

PURPOSE: To improve the potential for finding clinically important subtypes of patients with lower urinary tract symptoms we developed the CASUS (Comprehensive Assessment of Self-reported Urinary Symptoms). We used it to present data on the experiences of lower urinary tract symptoms in treatment seeking women and men from a prospective observational cohort. MATERIALS AND METHODS: We created an initial list of lower urinary tract symptoms that were confirmed in 22 qualitative interviews with providers, and 88 qualitative interviews with care seeking and noncare seeking women and men with lower urinary tract symptoms. Items from extant measures were adopted and revised, and new items were developed. All items were evaluated for understanding in 64 cognitive interviews. Items were administered to a prospective cohort of female and male patients with lower urinary tract symptoms who were seeking care. Analyses were done to describe item response distributions and correlations among item responses separately for women and men. RESULTS: A total of 444 males and 372 females provided responses to the CASUS. Several sets of items showed different relationships for women compared to men. In particular the associations between sensation related items and incontinence related items were generally positive among females but often negative among males. CONCLUSIONS: After using an intensive development process the CASUS addresses a wide range of lower urinary tract symptoms. It should help identify clinically important subtypes of patients. Further, item collection can provide the foundation for shorter measures for use in the clinic and as trial end points.

Patient Characteristics Associated with More Bother from Lower Urinary Tract Symptoms.

PURPOSE: Some patients continue to have bothersome lower urinary tract symptoms despite treatment. We examined characteristics associated with bother from lower urinary tract symptoms in a prospective cohort. MATERIALS AND METHODS: In this 1-year prospective, observational cohort study we obtained data on patients with lower urinary tract symptoms who were seeking care at a total of 6 tertiary care centers in the United States. Participants answered the AUA-SI (American Urological Association Symptom Index) global urinary bother question at study entry and 12 months later. Multilevel logistic and linear regression was used to identify factors associated with worsening bother and bother at 12 months, respectively. RESULTS: Of the 756 participants 121 (16%) had worsened lower urinary tract symptom bother during the study period. When adjusted for other variables, worsened lower urinary tract symptom bother was more likely among men who were nonwhite (OR 1.79, 95% CI 0.94-3.40) or who had diabetes (OR 1.68, 95% CI 0.86-3.27) and among women with diabetes (OR 1.77, 95% CI 0.85-3.67), prior treatment of lower urinary tract symptoms (OR 2.58, 95% CI 1.22-5.46) or a higher depression level (OR 1.29, 95% CI 1.10-1.52). Baseline factors associated with more severe bother at 12 months in men included more severe bother at baseline, nonwhite race, worse urinary frequency and incontinence, and higher levels of stress (p <0.05). Among women more severe bother at baseline, urinary urgency and frequency, and worse physical function were associated with more severe bother at 12 months. CONCLUSIONS: Urinary symptom severity at baseline, race, depression and psychological stress were associated with the bother of lower urinary tract symptoms in a prospective cohort of men and women treated at tertiary care facilities. These findings may inform the clinical care of patients with bothersome lower urinary tract symptoms and direct providers to better prognosticate for patients with challenging lower urinary tract symptoms cases.

Are three-day voiding diaries feasible and reliable? Results from the Symptoms of Lower Urinary Tract Dysfunction Research Network (LURN) cohort.

AIMS: The aims of this study were to assess the completeness of voiding diaries in a research context and to correlate diary data with patient-reported questionnaires. METHODS: Men and women enrolled in the Symptoms of Lower Urinary Tract Dysfunction Research Network (LURN) were given a 3-day voiding and fluid-intake diary to fill-out. Diaries were assessed for completeness and intake-output imbalances. They were assigned to one of four categories based on a percentage of missing data and fluid imbalance: no diary submitted, unusable (>40% missing void or intake volumes, or unphysiological fluid imbalance), usable but not complete, and complete. RESULTS: A total of 1064 participants were enrolled and 85% (n = 902) returned the bladder diary. Of the diaries returned, 94% (n = 845) had data on three separate days, 87% (n = 786) had no missing intake volumes, 61% (n = 547) had no missing voided volumes, and 70% (n = 635) had a fluid imbalance within 3 L across the 3-day time period, resulting in 50% (n = 448) of participants with 100% complete diaries. Younger age was associated with a higher likelihood of not submitting a diary, or submitting an unusable diary. Women had a higher likelihood of submitting an unusable diary or a usable but incomplete diary. CONCLUSION: Overall, 50% of LURN participants returned voiding diaries with perfectly complete data. Incomplete data for voided volumes was the most common deficiency. There was only a moderate correlation between diary data and questionnaire responses, indicating that diaries are a source of unique information.

Asymmetrical flow field-flow fractionation for improved characterization of human plasma lipoproteins.

High- and low-density lipoproteins (HDL and LDL) are attractive targets for biomarker discovery. However, ultracentrifugation (UC), the current methodology of choice for isolating HDL and LDL, is tedious, requires large sample volume, results in sample loss, and does not readily provide information on particle size. In this work, human plasma HDL and LDL are separated and collected using semi-preparative asymmetrical flow field-flow fractionation (SP-AF4) and UC. The SP-AF4 and UC separation conditions, sample throughput, and liquid chromatography/mass spectrometry (LC/MS) lipidomic results are compared. Over 600 µg of total proteins is recovered in a single SP-AF4 run, and Western blot results confirm apoA1 pure and apoB100 pure fractions, consistent with HDL and LDL, respectively. The SP-AF4 separation requires ~ 60 min per sample, thus providing a marked improvement over UC which can span hours to days. Lipidome analysis of SP-AF4-prepared HDL and LDL fractions is compared to UC-prepared HDL and LDL samples. Over 270 lipids in positive MS mode and over 140 lipids in negative MS mode are identified by both sample preparation techniques with over 98% overlap between the lipidome. Additionally, lipoprotein size distributions are determined using analytical scale AF4 coupled with multiangle light scattering (MALS) and dynamic light scattering (DLS) detectors. These developments position SP-AF4 as a sample preparation method of choice for lipoprotein biomarker characterization and identification. Graphical abstract ᅟ.

Prevalence and Characteristics of Urinary Incontinence in a Treatment Seeking Male Prospective Cohort: Results from the LURN Study.

PURPOSE: Male urinary incontinence is thought to be infrequent. We sought to describe the prevalence of urinary incontinence in a male treatment seeking cohort enrolled in the LURN (Symptoms of Lower Urinary Tract Dysfunction Research Network). MATERIALS AND METHODS: Study inclusion and exclusion criteria, including men with prostate cancer or neurogenic bladder, were previously reported. LURN participants prospectively completed questionnaires regarding lower urinary tract symptoms and other clinical variables. Men were grouped based on incontinence type, including 1) no urinary incontinence, 2) post-void dribbling only and 3) urinary incontinence. Comparisons were made using ANOVA and multivariable regression. RESULTS: Of the 477 men 24% reported no urinary incontinence, 44% reported post-void dribbling only and 32% reported urinary incontinence. African American men and those with sleep apnea were more likely to be in the urinary incontinence group than in the no urinary incontinence group (OR 3.2, p = 0.02 and OR 2.73, p = 0.003, respectively). Urinary incontinence was associated with significantly higher bother compared to men without leakage (p <0.001). Compared to men without urinary incontinence and men with only post-void dribbling those with urinary incontinence were significantly more likely to report higher scores (more severe symptoms) on the PROMIS (Patient-Reported Outcomes Measurement Information System) questionnaires regarding bowel issues, depression and anxiety than men without urinary incontinence (p <0.01). CONCLUSIONS: Urinary incontinence is common among treatment seeking men. This is concerning because the guideline recommended questionnaires to assess male lower urinary tract symptoms do not query for urinary incontinence. Thus, clinicians may be missing an opportunity to intervene and improve patient care. This provides a substantial rationale for a new or updated symptom questionnaire which provides a more comprehensive symptom assessment.

Symptom Based Clustering of Women in the LURN Observational Cohort Study.

PURPOSE: Women with lower urinary tract symptoms are often diagnosed based on a predefined symptom complex or a predominant symptom. There are many limitations to this paradigm as often patients present with multiple urinary symptoms which do not perfectly fit the preestablished diagnoses. We used cluster analysis to identify novel, symptom based subtypes of women with lower urinary tract symptoms. MATERIALS AND METHODS: We analyzed baseline urinary symptom questionnaire data obtained from 545 care seeking female participants enrolled in the LURN (Symptoms of Lower Urinary Tract Dysfunction Research Network) Observational Cohort Study. Symptoms were measured with the LUTS (lower urinary tract symptoms) Tool and the AUA SI (American Urological Association Symptom Index), and analyzed using a probability based consensus clustering algorithm. RESULTS: Four clusters were identified. The 138 women in cluster F1 did not report incontinence but experienced post-void dribbling, frequency and voiding symptoms. The 80 women in cluster F2 reported urgency incontinence as well as urgency and frequency but minimal voiding symptoms or stress incontinence. Cluster F3 included 244 women who reported all types of incontinence, urgency, frequency and mild voiding symptoms. The 83 women in cluster F4 reported all lower urinary tract symptoms at uniformly high levels. All but 2 of 44 LUTS Tool and 8 AUA SI questions significantly differed between at least 2 clusters (p <0.05). All clusters contained at least 1 member from each conventional group, including continence, and stress, urgency, mixed and other incontinence. CONCLUSIONS: Women seeking care for lower urinary tract symptoms cluster into 4 distinct symptom groups which differ from conventional clinical diagnostic groups. Further validation is needed to determine whether management improves using this new classification.

Baseline Lower Urinary Tract Symptoms in Patients Enrolled in LURN: A Prospective, Observational Cohort Study.

PURPOSE: We described and compared the frequency and type of lower urinary tract symptoms reported by men and women at the time that they were recruited from urology and urogynecology clinics into the Symptoms of Lower Urinary Tract Dysfunction Research Network multicenter, prospective, observational cohort study. MATERIALS AND METHODS: At 6 research sites treatment seeking men and women were enrolled who reported any lower urinary tract symptoms at a frequency more than rarely during the last month on the LUTS (Lower Urinary Tract Symptoms) Tool. At baseline the study participants underwent a standardized clinical evaluation and completed validated questionnaires. Urological tests were performed, including pelvic/rectal examination, post-void residual urine measurement and urinalysis. RESULTS: A total of 545 women and 519 men were enrolled in the study. Mean ± SD age was 58.8 ± 14.1 years. At baseline nocturia, frequency and a sensation of incomplete emptying were similar in men and women but men experienced more voiding symptoms (90% vs 85%, p = 0.007) and women reported more urgency (85% vs 66%, p <0.001). Women also reported more of any type of urinary incontinence than men (82% vs 51% p <0.001), which was mixed incontinence in 57%. Only 1% of men reported stress incontinence but they had other urinary incontinence, including post-void dribbling in 44% and urgency incontinence in 46%. Older participants had higher odds of reporting symptoms of nocturia and urgency. CONCLUSIONS: In this large, treatment seeking cohort of men and women lower urinary tract symptoms varied widely by gender and age. Men reported more voiding symptoms and nonstress or urgency urinary incontinence while women reported more incontinence overall and urgency. Older participants had greater odds of urgency and nocturia.

Dynamic analysis of the individual patterns of intakes, voids, and bladder sensations reported in bladder diaries collected in the LURN study.

The goal of this study was to perform an in-depth dynamic analysis of individual bladder diaries to inform which behavioral modifications would best reduce lower urinary tract symptoms, such as frequency and urgency. Three-day bladder diaries containing data on timing, volumes, and types of fluid intake, as well as timing, volumes, and bladder sensation at voids were analyzed for 197 participants with lower urinary tract symptoms. A novel dynamic analytic approach to bladder diary time series data was proposed and developed, including intra-subject correlations between time-varying variables: rates of intake, bladder filling rate, and urge growth rate. Grey-box models of bladder filling rate and multivariable linear regression models of urge growth rate were developed for individual diaries. These models revealed that bladder filling rate, rather than urine volume, was the primary determinant of urinary frequency and urgency growth rate in the majority of participants. Simulations performed with the developed models predicted that the most beneficial behavioral modifications to reduce the number of urgency episodes are those that smooth profiles of bladder filling rate, which might include behaviors such as exclusion of caffeine and alcohol and/or other measures, e.g., increasing number and decreasing volumes of intakes.

Dynamic analysis of the individual patterns of intakes, voids, and bladder sensations reported in bladder diaries collected in the LURN study.

The goal of this study was to develop the novel analytical approach and to perform an in-depth dynamic analysis of individual bladder diaries to inform which behavioral modifications would best reduce lower urinary tract symptoms, such as frequency and urgency. Three-day bladder diaries containing data on timing, volumes, and types of fluid intake, as well as timing, volumes, and bladder sensation at voids were analyzed for 197 participants with lower urinary tract symptoms. A novel dynamic analytic approach to bladder diary time series data was proposed and developed, including intra-subject correlations between time-varying variables: rates of intake, bladder filling rate, and urge growth rate. Grey-box models of bladder filling rate and multivariable linear regression models of urge growth rate were developed for individual diaries. These models revealed that bladder filling rate, rather than urine volume, was the primary determinant of urinary frequency and urgency growth rate in the majority of participants. Simulations performed with the developed models predicted that the most beneficial behavioral modifications to reduce the number of urgency episodes are those that smooth profiles of bladder filling rate, which might include behaviors such as exclusion of caffeine and alcohol and/or other measures, e.g., increasing number and decreasing volumes of intakes.

Label-free quantitative LC-MS proteomics of Alzheimer's disease and normally aged human brains.

Quantitative proteomics analysis of cortical samples of 10 Alzheimer's disease (AD) brains versus 10 normally aged brains was performed by following the accurate mass and time tag (AMT) approach with the high resolution LTQ Orbitrap mass spectrometer. More than 1400 proteins were identified and quantitated. A conservative approach of selecting only the consensus results of four normalization methods was suggested and used. A total of 197 proteins were shown to be significantly differentially abundant (p-values <0.05, corrected for multiplicity of testing) in AD versus control brain samples. Thirty-seven of these proteins were reported as differentially abundant or modified in AD in previous proteomics and transcriptomics publications. The rest to the best of our knowledge are new. Mapping of the discovered proteins with bioinformatic tools revealed significant enrichment with differentially abundant proteins of pathways and processes known to be important in AD, including signal transduction, regulation of protein phosphorylation, immune response, cytoskeleton organization, lipid metabolism, energy production, and cell death.

Subtyping of common complex diseases and disorders by integrating heterogeneous data. Identifying clusters among women with lower urinary tract symptoms in the LURN study.

We present a methodology for subtyping of persons with a common clinical symptom complex by integrating heterogeneous continuous and categorical data. We illustrate it by clustering women with lower urinary tract symptoms (LUTS), who represent a heterogeneous cohort with overlapping symptoms and multifactorial etiology. Data collected in the Symptoms of Lower Urinary Tract Dysfunction Research Network (LURN), a multi-center observational study, included self-reported urinary and non-urinary symptoms, bladder diaries, and physical examination data for 545 women. Heterogeneity in these multidimensional data required thorough and non-trivial preprocessing, including scaling by controls and weighting to mitigate data redundancy, while the various data types (continuous and categorical) required novel methodology using a weighted Tanimoto indices approach. Data domains only available on a subset of the cohort were integrated using a semi-supervised clustering approach. Novel contrast criterion for determination of the optimal number of clusters in consensus clustering was introduced and compared with existing criteria. Distinctiveness of the clusters was confirmed by using multiple criteria for cluster quality, and by testing for significantly different variables in pairwise comparisons of the clusters. Cluster dynamics were explored by analyzing longitudinal data at 3- and 12-month follow-up. Five clusters of women with LUTS were identified using the developed methodology. None of the clusters could be characterized by a single symptom, but rather by a distinct combination of symptoms with various levels of severity. Targeted proteomics of serum samples demonstrated that differentially abundant proteins and affected pathways are different across the clusters. The clinical relevance of the identified clusters is discussed and compared with the current conventional approaches to the evaluation of LUTS patients. The rationale and thought process are described for the selection of procedures for data preprocessing, clustering, and cluster evaluation. Suggestions are provided for minimum reporting requirements in publications utilizing clustering methodology with multiple heterogeneous data domains.

Clustering of the structures by using "snakes-&-dragons" approach, or correlation matrix as a signal.

Biological, ecological, social, and technological systems are complex structures with multiple interacting parts, often represented by networks. Correlation matrices describing interdependency of the variables in such structures provide key information for comparison and classification of such systems. Classification based on correlation matrices could supplement or improve classification based on variable values, since the former reveals similarities in system structures, while the latter relies on the similarities in system states. Importantly, this approach of clustering correlation matrices is different from clustering elements of the correlation matrices, because our goal is to compare and cluster multiple networks-not the nodes within the networks. A novel approach for clustering correlation matrices, named "snakes-&-dragons," is introduced and illustrated by examples from neuroscience, human microbiome, and macroeconomics.