Health Related Quality of Life for Stone Formers

Gender Disparities in Quality of Life Outcomes Among Kidney Stone Formers

Purpose: This study investigates gender-based disparities in health-related quality of life (HRQOL) outcomes among kidney stone patients and explores potential contributing factors. Methods: A retrospective review of medical records at the University of Rochester Medical Center was conducted on 2199 new urolithiasis patients who completed the Wisconsin Stone Quality of Life Questionnaire (WISQOL) standardized on a 0 to 100 scale. Demographic and clinical data were collected. Statistical analyses included univariate tests, chi-squared tests, and multivariate linear regression. Results: Of the 2199 kidney stone patients, 1085 (49.3%) were women. Women reported significantly lower quality of life (QoL) scores compared with men (71.6 vs 80.7; p < 0.001), and this persisted across all domains, including social impact (80.2 vs 86.9; p < 0.001), emotional impact (67.3 vs 77.1; p < 0.001), disease impact (67.3 vs 77.1; p < 0.001), and impact vitality (62.6 vs 72.9; p < 0.001). Female gender was identified as an independent predictor of diminished QoL scores, along with younger age, symptomatic status, number of surgeries, and presence of a psychosocial comorbidity. Conclusions: Our findings suggest that women with kidney stones experience lower HRQOL compared with men, even accounting for clinical and demographic factors. Although this study provides preliminary insights, additional research is needed to validate these findings in broader and more varied populations.

The impact of kidney stone disease on quality of life in high-risk stone formers

OBJECTIVE

To assess the impact of kidney stone disease (KSD) and its treatment on the health-related quality of life (HRQOL) of high-risk stone formers with hyperparathyroidism, renal tubular acidosis, malabsorptive disease, and medullary sponge kidney.

PATIENTS AND METHODS

The Wisconsin Stone Quality of Life questionnaire was used to evaluate HRQOL in 3301 patients with a history of KSD from 16 institutions in North America between 2014 and 2020. Baseline characteristics and medical history were collected from patients, while active KSD was confirmed through radiological imaging. The high-risk group was compared to the remaining patients (control group) using the Wilcoxon rank-sum test.

RESULTS

Of 1499 patients with active KSD included in the study, the high-risk group included 120 patients. The high-risk group had significantly lower HRQOL scores compared to the control group (P < 0.01). In the multivariable analyses, medullary sponge kidney disease and renal tubular acidosis were independent predictors of poorer HRQOL, while alkali therapy was an independent predictor of better HRQOL (all P < 0.01).

CONCLUSIONS

Among patients with active KSD, high-risk stone formers had impaired HRQOL with medullary sponge kidney disease and renal tubular acidosis being independent predictors of poorer HRQOL. Clinicians should seek to identify these patients earlier as they would benefit from prompt treatment and prevention.

Access to Care and Health Care Utilization Among Patients With Nephrolithiasis

OBJECTIVE

To characterize the impact of nephrolithiasis diagnosis and treatment on health care utilization and identify predictors of barriers to care in the patient population.

METHODS

We conducted a retrospective cohort study using the All of Us Database, a National Institutes of Health database targeting recruitment of underrepresented populations. Patients with a diagnosis of kidney stones were included and matched to a control group. Primary outcomes were patients' self-reported health care access and utilization. Univariable and multivariable regression analyses were performed.

RESULTS

9173 patients with a diagnosis of nephrolithiasis were included and matched to 9173 controls without a diagnosis of nephrolithiasis. Patients with kidney stones were less likely to have had >1 year since last provider visit (1.7% vs 3.8%, P <.001), but did not report increased delays obtaining care (31%), inability to afford care (11.4%), or higher likelihood of skipping medications (12.9%). Among patients with stones, 1208 (13.2%) had been treated surgically. On multivariable analysis, younger age, female sex, lower income, lower education, non-insured status, and lower physical and mental health were all associated with delays obtaining care, difficulty affording care, skipping medications, and/or prolonged time since seeing a provider.

CONCLUSION

A diagnosis of nephrolithiasis and subsequent surgical intervention were not associated with an increase in patient-reported barriers to care. However, among patients with nephrolithiasis, younger, comorbid, female patients from lower socioeconomic status are at significant risk of being unable to access and utilize treatment.

Association between drinking status and risk of kidney stones among United States adults: NHANES 2007-2018

OBJECTIVE

This study aimed to investigate the relationship between drinking status and kidney stones occurrence among United States (US) adults who consume alcohol.

METHODS

We conducted a cross-sectional analysis using data from the National Health and Nutrition Examination Survey (NHANES 2007-2018). Questionnaires yielded information on alcohol consumption and kidney health. Drinking status was categorized into four groups-former, mild, moderate, and heavy-based on alcohol consumption patterns. The aim was to explore the relationship between drinking status and the prevalence of kidney stones occurrence. For this analysis, we examined a group of individuals diagnosed with kidney stones. With survey weights applied, the total weight of the group was 185,690,415.

RESULTS

We used logistic regression to measure the relationship between drinking status and the likelihood of developing kidney stones. In a fully adjusted model, former drinkers were less likely to have previously experienced kidney stones (OR 0.762, 95% CI 0.595-0.977, P < 0.05). In subgroup analysis, heavy alcohol consumption was associated with a significantly reduced likelihood of kidney stones occurrence in various populations. The adjusted odds ratios (with 95% confidence intervals) of kidney stones risk for heavy alcohol consumption were 0.745 (0.566-0.981) for young individuals, 0.566 (0.342-0.939) for older individuals, 0.708 (0.510-0.981) for individuals of white race, 0.468 (0.269-0.817) for individuals with underweight/normal BMI, 0.192 (0.066-0.560) for widowed people, 0.538 (0.343-0.843) for smoking individuals, 0.749 (0.595-0.941) for individuals without a cancer history, and 0.724 (0.566-0.925) for individuals without a stroke history.

CONCLUSIONS

In US adults who consume alcohol, a negative linear relationship is apparent between drinking status and the prevalence of kidney stones, with heavy drinking showing a lower prevalence compared to former drinkers. However, the causal relationship between drinking status and kidney stones requires further investigation in future research endeavors.

Development and Preliminary Validation of the 6-Item Short Form of the Wisconsin Stone Quality of Life Questionnaire

OBJECTIVE

To develop a short form of the Wisconsin Stone Quality of Life (WISQOL): 1) identify the smallest subset of items from WSIQOL that accurately predict patients' health-related quality of life (HRQOL), and 2) in a clinical patient population, test these items-grouped together to form the WISQOL-short form (SF) - and assess its convergent validity.

MATERIALS AND METHODS

The items for the WISQOL-SF were identified based on classic item analysis theory. Patients who previously completed the original 28-item WISQOL were randomly split into 2 groups of equal size. Scores for the WISQOL were calculated for one group while those for the WISQOL-SF were calculated for the other. Cronbach's alpha coefficients were calculated. Impacts of demographic and clinical factors as well as stone and symptom status at the time of WISQOL completion were examined.

RESULTS

Patients (n = 740) who completed the WISQOL between 6/2017 and 11/2021 were included. Patients were 48% male, 54.1 ± 14.6 years old, and had a BMI of 31.2 ± 8.1. After item analysis and reduction, the six items ultimately included in the WISQOL-SF represented 2 of the 4 domains (social and emotional) of the original WISQOL. The internal consistency of the WISQOL-SF was similar to the original (Cronbach's alpha 0.943 vs. 0.973). No differences for health-related quality of life were found between groups (P = .567).

CONCLUSION

The WISQOL-SF demonstrated the expected differences for gender and between patients with and without stone-related symptoms at the time of WISQOL completion. The WISQOL-SF showed good consistency and produced similar HRQOL scores to the full-form WISQOL.

The Financial Burden of Nephrolithiasis and Predictors of Disease-specific Financial Toxicity

OBJECTIVE

To characterize stone-related financial toxicity among US adults with kidney stones through validated questionnaires for financial toxicity and disease-specific health-related quality of life.

MATERIALS AND METHODS

We performed a cross-sectional survey of adults with kidney stone disease from the general population ascertained through a national registry of volunteers (ResearchMatch). A computer-based survey queried stone event history and related costs for medical care, disease-specific quality of life (WISQOL), and an 11-item measure of stone-related financial toxicity (COST-11 score). Multivariable logistic regression was performed to evaluate predictors of financial toxicity, defined as having a COST-11 score ≤20.

RESULTS

Of 942 responses, median COST-11 score was 29 (IQR 21-38), and 24.7% (N = 233) met criteria for disease-specific financial toxicity. Stone-formers with financial toxicity spent more out of pocket on stone-treatment in the previous year than patients with lower financial burden (P <.001) and were more likely to defer or delay recommended treatment due to anticipated cost (27% vs 3%; P <.001). Stone-specific financial toxicity was associated with poorer disease-specific health-related quality of life across all WISQOL domains (each P <.001). Multivariable logistic regression showed that female gender (OR 1.81; 95% CI 1.24-2.67), Medicaid compared to private insurance (OR 3.91; 95% CI 2.34-6.94), and stone passage in the previous year (OR 2.00; 95% CI 1.41-2.86) were independently associated with financial toxicity.

CONCLUSION

Approximately 1 in 4 individuals with kidney stone disease report disease-specific financial toxicity. These data suggest the financial burden of the condition may influence decision-making and associates with poorer disease-specific quality of life.

Validation of the Italian version of wisconsin stone quality of life (WISQOL): a prospective Italian multicenter study

Urolithiasis is a worldwide spread condition that affects patients' Health-Related Quality of Life (HRQOL), which measurement is an important tool for routine clinical and research practice. Disease-specific HRQOL measures demonstrated to perform better in assessing the effects of specific conditions. A disease-specific questionnaire for kidney stones, the WISQOL, has been validated in different languages, but an Italian version is still missing. Our aim is to produce and validate the Italian version of WISQOL (IT-WISQOL). Patients undergoing any elective treatment for upper urinary tract stones were enrolled. A multi-step process with forward- and back-translation was used to translate WISQOL into Italian. Patients were evaluated within 15 days pre-operatively and then at 30-, 90 days post-operatively and administered both IT-WISQOL and SF-36v2. Post-operative data such as 30 days postoperative complications, late stone-related events, successful status, and stone complexity were collected. Cronbach's α was used to evaluate the internal consistency of IT-WISQOL, while Spearman's rho was used for item and inter-domain correlations and IT-WISQOL with SF-36v2 correlation. We found excellent internal consistency across all domains (α ≥ 0.88), particularly when the total score is considered (α = 0.960). Test-retest reliability showed excellent results for the total questionnaire (Pearson correlation value: 0.85). The Inter-domain association ranged from 0.497 to 0.786. Convergent validity was confirmed by a good correlation with subdomains of the SF-36v2 measures. IT-WISQOL is a reliable tool to measure HRQOL in stone patients. It shows analog characteristics if compared to English WISQOL.

Patient-reported outcome measures (PROMs) in stone surgery: A multi-centre study of patient experience of flexible ureteroscopy (fURS) versus extracorporeal shockwave lithotripsy (SWL)

Objectives:

To compare patient-reported outcome measures (PROMs) for patients with symptomatic renal stone disease treated by flexible ureterorenoscopy (fURS) and shockwave lithotripsy (SWL)

Introduction:

Historically, surgical outcomes are measured by surgeon-specific outcomes such as ‘stone-free rates’. More recently, there is increasing emphasis on PROMs to ascertain a patient’s perspective of their own surgical outcome. Despite this, the literature in reference to renal stone-specific PROMs following stone treatment remains limited.

Methods:

Data were collected in a prospective multi-centre study. Patients undergoing fURS or SWL were asked to complete the validated Cambridge Renal Stone Patient Reported Outcome Measure ( CReSP) on the day of initial treatment and at weeks 1, 6 and 12 post-operatively.

Results:

Data were collected for 119 patients. Three were excluded as stone metric and demographic details were incomplete. Sixty underwent SWL and 56 underwent fURS. Median stone size was 7.52 mm. There were no significant differences in baseline PROM scores between the treatment groups. At 1 week, the PROM scores were significantly higher in the fURS group compared to SWL (27.40 ± 0.85sd versus 22.51 ± 1.07sd; p < 0.05). However, at 6 and 12 weeks, the PROM scores were significantly lower in the fURS group (18.51 ± 2.27sd versus 23.67 ± 1.30sd; p < 0.05) and (17.01 ± 2.29sd versus 22.49 ± 1.49sd; p < 0.05), respectively. By week 12, overall scores for anxiety and social factors were more favourable in the fURS cohort.

Conclusion:

Our study suggests that fURS is associated with a short-lived increase in morbidity in comparison with SWL, which may be due to ureteric stenting in the majority of patients post-operatively. However, fURS patients appear to report significantly better PROM scores in the longer term. This appears to be associated with more favourable anxiety and social factor scoring over the treatment period.

Level of evidence:

Not applicable.

The duration of stone disease and the impact of a stone event on patients' quality of life

INTRODUCTION

With a 5-year stone recurrence rate of 30-50%, kidney stone formers are subject to significant morbidity which negatively impacts their Health Related Quality of Life (HRQOL). We sought to determine the impact of age of kidney stone onset, duration of stone disease, and kidney stone event (surgery or stone passage) on patients' individual HRQOL by querying the validated and prospectively collected Wisconsin Stone Quality of Life (WISQOL) database.

MATERIALS AND METHODS

Cross-sectional data were obtained from a total of 2,438 kidney stone formers from 14 institutions in North America who completed the WISQOL questionnaire from 2014 to 2019. The 28-question survey has a 1-5 point scale for each item (total score range 0-140). Multivariable linear regression models assessed the impact of age of kidney stone onset, duration of stone disease and time since most recent surgery or stone passage on HRQOL.

RESULTS

Of 2,438 patients, older age at kidney stone onset and longer duration of disease were both independent predictors of better WISQOL (β=0.33 points/year; CI 0.17-0.49; p<0.001 and β=0.50 points/year; CI 0.32-0.68; p<0.001, respectively). Of 1,376 patients with surgery between 2010-2019, increased time since most recent surgery was an independent predictor of better WISQOL scores (β = 2.28 points/year; CI: 1.47-3.10; p=<0.001). Of 1,027 patients with spontaneous stone passage between 2010-2019, increased time since most recent stone passage was an independent predictor of better WISQOL scores (β = 1.59 points/year; CI: 0.59-2.59; p=<0.05).

CONCLUSION

Our study demonstrates that older age of onset, longer duration of disease, increase time from most recent surgery or stone passage were independent predictors of better HRQOL in kidney stone formers. Results of future studies that focus on optimizing stone related modifiable risk factors to decrease the amount of recurrent stone episodes and thus the need for recurrent surgeries will be essential.

Kidney Stone Events Following Parathyroidectomy vs Nonoperative Management for Primary Hyperparathyroidism

CONTEXT

Primary hyperparathyroidism (PHPT) is associated with an increased risk of kidney stones. Few studies account for PHPT severity or stone risk when comparing stone events after parathyroidectomy vs nonoperative management.

OBJECTIVE

Compare the incidence of kidney stone events in PHPT patients treated with parathyroidectomy vs nonoperative management.

DESIGN

Longitudinal cohort study with propensity score inverse probability weighting and multivariable Cox proportional hazards regression.

SETTING

Veterans Health Administration integrated health care system.

PATIENTS

A total of 44 978 patients with > 2 years follow-up after PHPT diagnosis (2000-2018); 5244 patients (11.7%) were treated with parathyroidectomy.

MAIN OUTCOMES MEASURE

Clinically significant kidney stone event.

RESULTS

The cohort had a mean age of 66.0 years, was 87.8% male, and 66.4% White. Patients treated with parathyroidectomy had higher mean serum calcium (11.2 vs 10.8mg/dL) and were more likely to have a history of kidney stone events. Among patients with baseline history of kidney stones, the unadjusted incidence of ≥ 1 kidney stone event was 30.5% in patients managed with parathyroidectomy (mean follow-up, 5.6 years) compared with 18.0% in those managed nonoperatively (mean follow-up, 5.0 years). Patients treated with parathyroidectomy had a higher adjusted hazard of recurrent kidney stone events (hazard ratio [HR], 1.98; 95% CI, 1.56-2.51); however, this association declined over time (parathyroidectomy × time: HR, 0.80; 95% CI, 0.73-0.87).

CONCLUSION

In this predominantly male cohort with PHPT, patients treated with parathyroidectomy continued to be at higher risk of kidney stone events in the immediate years after treatment than patients managed nonoperatively, although the adjusted risk of stone events declined with time, suggesting a benefit to surgical treatment.

Subjective cognitive decline symptoms and its association with socio-demographic characteristics and common chronic diseases in the southern Chinese older adults

Background

Subjective cognitive decline (SCD) may be the first symptomatic manifestation of Alzheimer’s disease, but information on its health correlates is still sparse in Chinese older adults. This study aimed to estimate SCD symptoms and its association with socio-demographic characteristics, common chronic diseases among southern Chinese older adults.

Methods

Participants aged 60 years and older from 7 communities and 2 nursing homes in Guangzhou were recruited and interviewed with standardized assessment tools. Pittsburgh Sleep Quality Index (PSQI), Patient Health Questionnaire–9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were used to measure poor sleep quality, depression symptoms and anxiety symptoms. The SCD symptoms were measured by SCD questionnaire 9 (SCD-Q9) which ranged from 0 to 9 points, with a higher score indicating increased severity of the SCD. Participants were divided into low score group (SCD-Q9 score ≤ 3) and higher score group (SCD-Q9 score > 3). Chi-square tests and multivariate logistic regression analysis were used for exploring the influences of different characteristics of socio-demographic and lifestyle factors on SCD symptoms. Univariate and multivariate logistic regression analysis were applied to explore the association between SCD symptoms with common chronic diseases.

Results

A total of 688 participants were included in our analysis with a mean age of 73.79 (SD = 8.28, range: 60–101), while 62.4% of the participants were females. The mean score of the SCD-Q9 was 3.81 ± 2.42 in the whole sample. A total of 286 participants (41.6%) were defined as the low score group (≤3 points), while 402 participants (58.4%) were the high score group (> 3 points). Multivariate logistic regression analysis revealed that female (OR = 1.99, 95%CI: 1.35–2.93), primary or lower education level (OR = 2.58, 95%CI: 1.38–4.83), nursing home (OR = 1.90, 95%CI: 1.18–3.05), napping habits (OR = 1.59, 95%CI: 1.06–2.40), urolithiasis (OR = 2.72, 95%CI: 1.15–6.40), gout (OR = 2.12, 95%CI: 1.14–3.93), poor sleep quality (OR = 1.93, 95%CI: 1.38–2.71), depression symptoms (OR = 3.01, 95%CI: 1.70–5.34) and anxiety symptoms (OR = 3.11, 95%CI: 1.29–7.46) were independent positive related to high SCD-Q9 score. On the other hand, tea-drinking habits (OR = 0.64, 95%CI: 0.45–0.92), current smoking (OR = 0.46, 95%CI: 0.24–0.90) were independent negative related to high SCD-Q9 score.

Conclusions

Worse SCD symptoms were closely related to common chronic diseases and socio-demographic characteristics. Disease managers should pay more attention to those factors to early intervention and management for SCD symptoms among southern Chinese older adults.

Association of meteorological factors and ambient air pollution on medical care utilization for urolithiasis: a population-based time-series study

BACKGROUND

To identify the association of meteorological factors/ambient air pollutants with medical care utilization for urolithiasis and estimate the effect size/time lags.

METHODS

This is a population-based time-series analysis of 300,000 urolithiasis cases from eight large metropolitan areas in Korea. Seventeen meteorological factors and ambient air pollutants were measured daily during 2002-2017 for each metropolis. Data on daily medical utilization owing to urolithiasis were collected. A generalized additive model was used while factoring in the nonlinear relationship between meteorological factors/ambient air pollutants and urolithiasis and a time lag of ≤10 days. A multivariate analysis was performed. Backward elimination with an Akaike information criterion was used for fitting the multivariate model.

RESULTS

Urolithiasis was significantly associated with average temperature, diurnal temperature range, sunshine duration, particulate matter (PM) ≤2.5 μm, and carbon monoxide (CO) levels. The incidence of ureteral stones was positively correlated with average temperature, PM ≤2.5 μm level, and CO level (time lags 0-9, 2-4, and 0-9 days, respectively). The incidence of renal stones was positively correlated with PM ≤2.5 μm and CO levels (time lags 2-4 and 0-9 days, respectively). PM ≤2.5 μm (0.05 and 0.07% per 10 μg/m³⁾ and CO (2.05 and 2.25% per 0.1 ppm) conferred the highest excess risk on ureteral and renal stones.

CONCLUSIONS

Urolithiasis is affected by various meteorological factors and ambient air pollutants, PM ≤2.5 μm, and CO levels may be novel potential risk factors for this condition.

Does early intervention improve outcomes for patients with acute ureteral colic?

OBJECTIVES

Early surgical intervention is increasingly employed for patients with ureteral colic, but guidelines and current practice are variable. We compared 60-day outcomes for matched patients undergoing early intervention vs. spontaneous passage.

METHODS

This multicentre propensity-matched cohort analysis used administrative data and chart review to study all eligible emergency department (ED) patients with confirmed 2.0-9.9 mm ureteral stones. Those having planned stone intervention within 5 days comprised the intervention cohort. Controls attempting spontaneous passage were matched to intervention patients based on age, sex, stone width, stone location, hydronephrosis, ED site, ambulance arrival and acuity level. The primary outcome was treatment failure, defined as rescue intervention or hospitalization within 60 days, using a time to event analysis. Secondary outcome was ED revisit rate.

RESULTS

Among 1154 matched patients, early intervention did not reduce the risk of treatment failure (adjusted hazard ratio 0.94; P = 0.61). By 60 days, 21.8% of patients in both groups experienced the composite primary outcome (difference 0.0%; 95% confidence interval - 4.8 to 4.8%). Intervention patients required more hospitalizations (20.1% vs. 12.8%; difference 7.3%; 95% CI 3.0-11.5%) and ED revisits (36.1% vs. 25.5%; difference 10.6%; 95% CI 5.3-15.9%), but (insignificantly) fewer rescue interventions (18.9% vs. 21.3%; difference - 2.4%; 95% CI - 7.0 to 2.2%).

CONCLUSIONS

In matched patients with 2.0-9.9 mm ureteral stones, early intervention was associated with similar rates of treatment failure but greater patient morbidity, evidenced by hospitalizations and emergency revisits. Physicians should adopt a selective approach to interventional referral and consider that spontaneous passage probably provides better outcomes for many low-risk patients.

Disparities in Kidney Stone Disease: A Scoping Review

PURPOSE

We reviewed the available evidence regarding health disparities in kidney stone disease to identify knowledge gaps in this area.

MATERIALS AND METHODS

A literature search was conducted using PubMed®, Embase® and Scopus® limited to articles published in English from 1971 to 2020. Articles were selected based on their relevance to disparities in kidney stone disease among adults in the United States.

RESULTS

Several large epidemiological studies suggest disproportionate increases in incidence and prevalence of kidney stone disease among women as well as Black and Hispanic individuals in the United States, whereas other studies of comparable size do not report racial and ethnic demographics. Numerous articles describe disparities in imaging utilization, metabolic workup completion, analgesia, surgical intervention, stone burden at presentation, surgical complications, followup, and quality of life based on race, ethnicity, socioeconomic status and place of residence. Differences in urinary parameters based on race, ethnicity and socioeconomic status may be explained by both dietary and physiological factors. All articles assessed had substantial risk of selection bias and confounding.

CONCLUSIONS

Health disparities are present in many aspects of kidney stone disease. Further research should focus not only on characterization of these disparities but also on interventions to reduce or eliminate them.

Predictors of Repeat Surgery and Stone-related Events After Flexible Ureteroscopy for Renal Stones

OBJECTIVES

To evaluate the risk of repeat surgery and stone-related events after flexible ureteroscopy (fURS) for renal stones, and to identify their predictive factors.

PATIENTS AND METHODS

This was a single-center, retrospective cohort study of patients (n = 664) who underwent fURS for renal stones with or without concomitant ureteral stones between January 2012 and December 2019. The primary outcomes were time to ipsilateral stone-related surgical intervention and any stone-related event (including ipsilateral renal colic, symptomatic ureteral calculi, obstructive urinary tract infection, and surgical intervention).

RESULTS

During median follow-up of 31.1 months, 103 (15.5%) and 135 (20.3%) patients experienced surgical intervention and any stone-related event, respectively. The estimated 2-year intervention-free survival and stone-event-free survival was 86.9% and 81.6%, respectively. On Cox multivariate analysis, younger age (hazard ratio [HR] 0.96), history of stone surgery (HR 2.17), larger preoperative stone burden (HR 1.03), and larger residual fragment (HR 1.09) showed an association with future intervention. Use of the four identified risk factors (age ≤60, history of stone surgery, stone burden ≥20 mm, and residual fragment ≥4 mm) allowed stratification of patients based on the risk of future intervention (low [score: 0-1], intermediate [2], and high [3-4] risk). The estimated 2-year intervention-free survival rates in low-, intermediate-, and high-risk groups were 96.2%, 86.4%, and 71.3%, respectively.

CONCLUSION

Patients undergoing fURS are at risk of future ipsilateral surgical intervention and stone-related events. Our simple predictive tool can facilitate treatment decision-making by identifying patients who are at high risk of recurrence.

The impact of the number of lifetime stone events on quality of life: results from the North American Stone Quality of Life Consortium

To evaluate the impact of chronic stone recurrence on an individual's quality of life using the validated Wisconsin Stone Quality of Life (WISQOL) questionnaire. We collected cross-sectional data on patients with kidney stones from 14 institutions in North America. A stone event was defined as renal colic, stone-related procedure or emergency department visit. The regression analyses using general linear models and pairwise comparison determined the impact of the number of stone events on quality of life. The median number of stone events among the 2205 patients who completed the questionnaire was 3 (IQR 1-6). The mean total score was 107.4 ± 28.7 (max 140 points). The number of lifetime stone events was an independent predictor of lower quality of life (p < 0.001), specifically, score declined significantly beyond five events. Compared with patients who experienced a single stone event, there was a 0.4, 2.5, and 6.9 point decline in the adjusted mean WISQOL score after 2-5, 6-10, or > 10 events, respectively. The cumulative number of lifetime stone events was associated with a lower quality of life when more than five stone events were occurred. These findings underscore the importance of efforts to determine the underlying metabolic etiology of urolithiasis in the recurrent stone former, and the institution of a regimen to place their stone disease in remission.

Estimating the health-related quality of life of kidney stone patients: initial results from the Wisconsin Stone Quality of Life Machine-Learning Algorithm (WISQOL-MLA)

OBJECTIVE

To build the Wisconsin Stone Quality of Life Machine-Learning Algorithm (WISQOL-MLA) to predict urolithiasis patients' health-related quality of life (HRQoL) based on demographic, symptomatic and clinical data collected for the validation of the Wisconsin Stone Quality-of-Life (WISQOL) questionnaire, an HRQoL measurement tool designed specifically for patients with kidney stones.

MATERIAL AND METHODS

We used data from 3206 stone patients from 16 centres. We used gradient-boosting and deep-learning models to predict HRQoL scores. We also stratified HRQoL scores by quintile. The dataset was split using a standard 70%/10%/20% training/validation/testing ratio. Regression performance was evaluated using Pearson's correlation. Classification was evaluated with an area under the receiver-operating characteristic curve (AUROC).

RESULTS

Gradient boosting obtained a test correlation of 0.62. Deep learning obtained a correlation of 0.59. Multivariate regression achieved a correlation of 0.44. Quintile stratification of all patients in the WISQOL dataset obtained an average test AUROC of 0.70 for the five classes. The model performed best in identifying the lowest (0.79) and highest quintiles (0.83) of HRQoL. Feature importance analysis showed that the model weighs in clinically relevant factors to estimate HRQoL, such as symptomatic status, body mass index and age.

CONCLUSIONS

Harnessing the power of the WISQOL questionnaire, our initial results indicate that the WISQOL-MLA can adequately predict a stone patient's HRQoL from readily available clinical information. The algorithm adequately relies on relevant clinical factors to make its HRQoL predictions. Future improvements to the model are needed for direct clinical applications.

Is Stone-free Status After Surgical Intervention for Kidney Stones Associated With Better Health-related Quality of Life? - A Multicenter Study From the North American Stone Quality of Life Consortium

OBJECTIVE

To compare the health-related quality of life (HRQOL) of patients with residual fragments after surgical intervention for kidney stones to patients that are stone-free using the disease-specific Wisconsin stone quality of life (WISQOL) questionnaire. Kidney stones contribute to impaired HRQOL, which is increasingly recognized as an important healthcare outcome measurement.

MATERIALS AND METHODS

With institutional review board approval, 313 adult patients who underwent surgical intervention for kidney stones at 4 sites completed a WISQOL questionnaire. We retrospectively collected surgical data including presence of residual fragments on post-operative imaging. We calculated standardized WISQOL total and domain scores (0-100), which included items related to social functioning (D1), emotional functioning (D2), stone-related impact (D3), and vitality (D4). Scores were compared between patients with residual fragments to those who were stone-free after surgical intervention.

RESULTS

Demographics did not differ between groups, overall mean age 54.6 ± 13.5 and 55.4% female. There was no significant difference in total WISQOL score for patients with residual fragments (n = 124) compared to patients that were stone-free (n = 189), 110.5 ± 27.8 vs 115.4 ± 23.6 respectively, (P = .12). Interestingly, patients with residual fragments who underwent secondary surgery were found to have significantly lower total WISQOL score (88.4 ± 30.1 vs 116.6 ± 25.0, P <.0001).

CONCLUSION

Stone-free status after surgical intervention is not associated with better HRQOL when compared with patients whose surgeries left residual fragments. Indeed, further surgical intervention on residual fragments to achieve stone-free status may actually result in worse HRQOL.

Risk factors for urinary stone

Urolithiasis is one of the most common urologic diseases in Korea. The annual incidence of urolithiasis in Korea has increased over time. Understanding the epidemiology and risk factors for urolithiasis is essential for patient care and prevention. The purpose of this review was to summarize the recent literature regarding the risk factors for urolithiasis. The available Korean-population-based trials were enrolled in this study. The peak incidence age was the fifth to sixth decades in Korea. There has been a persistent male predominance in the prevalence and incidence of stone disease. The gender gap has continuously narrowed over the world. Climate and seasonal variations, such as temperature and humidity, have a profound effect on the development of urolithiasis. Various dietary factors, including calcium, sodium, animal protein, and oxalate, play an important role in the development of urolithiasis. Dehydration is a wellknown risk factor for stone disease. Many metabolic diseases can affect urolithiasis, including obesity, hypertension, diabetes, gout, and metabolic syndrome. The fast-moving super-aged society and global warming can increase stone disease burden in the near future. To prevent and reduce stone diseases, clinicians should understand the risk factors affecting stone formation.

What is the relationship of stress to patients' kidney stone-related quality of life?

INTRODUCTION

Health-related quality of life (HRQOL) is decreased in patients with kidney stones at all stages of stone disease, even when asymptomatic. Stress is thought to contribute to HRQOL, although there has been minimal investigation into the effect of stress on stone-related quality of life (QOL). We used the Wisconsin Stone Quality of Life Questionnaire (WISQOL) to assess the relationship of stress to stone-related QOL in kidney stone patients.

METHODS

As part of the WISQOL Research Consortium, patients were approached in outpatient clinics and completed the WISQOL and the Perceived Stress Scale 10-item questionnaire (PSS-10). Patients with stones at enrollment were divided into those with symptoms and those without, while patients with no current stones formed another group. Questionnaire scores from each group were compared statistically and correlations between the groups were calculated.

RESULTS

Patients (n=704) were enrolled from six centers. The WISQOL successfully discriminated between patients with current stones and those without (p<0.0001), while the PSS-10 did not (p=0.0869). The PSS-10 revealed patients with symptomatic kidney stones experienced higher levels of general stress than asymptomatic subjects (p<0.0001). However, a Pearson correlation test comparing the responses from each instrument revealed no overall correlation between general stress and HRQOL (r=0.05).

CONCLUSIONS

Symptomatic kidney stones increase general stress, as these patients demonstrate higher PSS-10 scores. Despite this, no correlation exists between general stress and stone-related QOL in patients with stone disease regardless of their stone and symptom status. This implies the existence of other factors impacting QOL in these patients, which warrants further exploration.

The effect of shock wave lithotripsy and retrograde intrarenal surgery on health-related quality of life in 10-20 mm renal stones: a prospective randomized pilot study

The effects of treatment modalities such as retrograde intrarenal surgery (RIRS) and shock wave lithotripsy (SWL) on health-related quality of life (HRQoL) were determined in patients with renal stones between 10 and 20 mm. A total of 120 patients were included in the study and prospectively randomized to RIRS or SWL group. A total of 39 patients experienced treatment failure and finally 81 patients (45 patients in the RIRS group, 36 patients in the SWL group) were analyzed for HRQoL. SF-36 survey was used to determine HRQoL pre-operatively, post-operative day 1 and 1 month. The patient and stone characteristics such as age, gender, stone size, grade of hydronephrosis and body mass index were similar between the two groups. At post-operative day 1, the RIRS group was associated with lower scores of role functioning/physical (p = 0.008), role functioning/emotional (p = 0.047) energy/fatigue (p = 0.011), social functioning (p = 0.003) and pain (p = 0.003) when compared to the SWL group. At post-operative 1 month, only pain and emotional well-being scores (p = 0.012 and p = 0.011, respectively) in the RIRS group were statistically lower according to the SWL group. In our study, patients in the SWL group showed more favorable HRQoL scores when compared to the patients in the RIRS group in short-term follow-up.

Validation of the French version of the Wisconsin Quality of Life (WISQOL) questionnaire for patients with nephrolithiasis

INTRODUCTION

The Wisconsin Stone Quality of Life (WISQOL) questionnaire has been recently developed to objectively assess quality of life (QOL) in patients with nephrolithiasis. However, a French version of the questionnaire was lacking. Therefore, the aim of the present study was to develop and validate the French version of this tool.

METHODS

The French version of the WISQOL (F-WISQOL) was developed in a multistep process involving primary translation, back-translation, and pilot testing among a group of patients (n=12). Nephrolithiasis patients from two tertiary care institutions were recruited into this study and completed the following questionnaires: the medical history form and either the WISQOL or F-WISQOL. Internal consistency was assessed using Cronbach's α, and inter-domain associations were evaluated using Spearman's rank correlation (r). One-way ANOVA was used to compare scores from the two groups (WISQOL and F-WISQOL).

RESULTS

A total of 210 patients were enrolled in this study: 68 in the WISQOL group and 148 in the F-WISQOL group. Internal consistency was high for all domains in both groups (F-WISQOL: 0.924-0.970; WISQOL: 0.888-0.965). No statistically significant difference was found between the two groups' scores. Inter-domain association, measured by Spearman correlation, was moderate to very strong between all the domains in the F-WISQOL. Values ranged from r=0.676-0.915, with acceptable correlation between D1, D2, and D3, but weaker correlation between D4 (vitality) and the three other domains (r=0.676-0.729).

CONCLUSIONS

In the present study, the French version of the WISQOL questionnaire was validated at two academic institutions.

Metabolic Syndrome Negatively Impacts Stone-Specific Quality of Life

Purpose: Metabolic syndrome (MetS) is a cluster of metabolic diseases that is linked to atherosclerotic cardiovascular disease. MetS has also been linked to increased nephrolithiasis. However, limited research has been conducted on MetS and its impact on stone-specific health-related quality of life (HRQOL). This study aims to examine the hypothesis that the presence of MetS is associated with decreased HRQOL. Materials and Methods: The Wisconsin Stone Quality of Life Questionnaire, a stone-specific HRQOL questionnaire, was used to survey 3051 patients with kidney stones. Medical history was collected from patients. These data were used to distinguish MetS patients from non-MetS patients. Among patients with current stones, a Wilcoxon rank sum test was used to compare HRQOL scores from MetS patients and non-MetS patients. HRQOL from patients with and without individual MetS components were also compared, and a multivariate analysis was conducted. Results: Statistical comparison between MetS patients (median score 102/140) and non-MetS patients (median score 106/140) demonstrated a lower stone-specific HRQOL in patients with MetS (p = 0.049). Among individual MetS components, patients with diabetes mellitus (DM) or body mass index (BMI) >30 had significantly lower HRQOL than patients without DM or BMI <30 (p = 0.028 and p < 0.001, respectively). The multivariate analysis supported this trend as MetS remained a significant predictor of decreased HRQOL (p = 0.002) after controlling for other variables assessed. Conclusions: This study indicates an association between MetS and a lower stone-specific QOL. This has important implications for stone prevention strategies in patients with MetS. Clinical Trial Registration number: H14-01143.

Translation and Linguistic Validation of the Korean Version of the Wisconsin Stone Quality of Life Questionnaire

Purpose

Although cure rate and efficacy of treatment for urinary stone disease have been improved, clinicians have been indifferent to the quality of life (QoL) of stone patients in Korea. The objective of this study was to develop a Korean version of Wisconsin questionnaire about quality of life questionnaire (K-WISQOL) of stone patients for use in Korea.

Methods

Linguistic validation was permitted for translation by its developers. Three bilingual nonspecialists and 11 panels who were actively involved in treating urinary stone patients performed the translation and linguistic validations. A trained interviewer and 5 Korean patients carried out cognitive debriefing.

Results

Noun words such as “energy” and “responsibilities” were very difficult to translate to Korean. They were substituted by more comprehensive words. After backward translation, translated sentences showed a good agreement with the original WISQOL. During backward translation and the second reconciliation, previously translated Korean version was revised in 5 sentences. In the cognitive debriefing process, all 5 patients thought that these questions explained the patient’s situation well. Most of these respondents answered that explanatory notes of questionnaire were well written and the format of the questionnaire was easy to follow.

Conclusions

The present study demonstrated that, despite language differences, translation and linguistic validation of the K-WISQOL were successfully performed. This K-WISQOL could be useful tools for treatment plan and patient care.

The effect of travel distance on health-related quality of life for patients with nephrolithiasis

INTRODUCTION

Urolithiasis causes a significant impact on health-related quality of life (HRQOL). Patients with kidney stones have high levels of stress and anxiety. Symptom resolution often requires treatment. Travel distance is a barrier to care but little is known about its effects on HRQOL. We hypothesize that increased distance to treatment site is associated with decreased HRQOL.

METHODS

Patients with a history of stones were enrolled at 11 tertiary centers as part of the QOL Stone Consortium of North America. HRQOL data were obtained using the Wisconsin Stone Quality of Life questionnaire (WISQOL). We calculated distance between patient and treatment site using national ZIP codes. We used linear models to evaluate the effect of distance on HRQOL, while also considering demographics data, stones/symptom status, and distance.

RESULTS

Of the 1676 enrolled patients, 52% were male, 86% non-Latino White, and the mean age was 53 years. Mean distance to treatment site was 63.3 km (range 0-3774), with 74% reporting current stones and 45% current symptoms. WISQOL score and distance were negatively correlated for patients reporting current stones and symptoms (p=0.0010). Linear modelling revealed decreased WISQOL scores for patients with symptoms as distance increased from treatment site (p=0.0001), with a 4.7-point decrease for every 100 km traveled.

CONCLUSIONS

Stone disease imposes significant burden on patients' HRQOL due to a variety of factors. Patients with active stone symptoms report worse HRQOL with increased distance to their treatment site. Possible etiologies include travel burden, increased disease burden, decreased healthcare use, and delays in care.

Study on the prevalence and incidence of urolithiasis in Korea over the last 10 years: An analysis of National Health Insurance Data

Purpose

We aimed to analyze the incidence and prevalence of urolithiasis in Korea over the last decade using the National Health Insurance (NHI) sample cohort data.

Materials and Methods

From January 2002 to December 2013, we enrolled sample cohort data from the NHI. Patients diagnosed with international classification of diseases code N20 or N13.2 were included. The incidence and prevalence rate was counted from the same period and patients previously diagnosed with urolithiasis were excluded. We compared the incidence and prevalence of urolithiasis by region, age, and sex, and identified the changes.

Results

Total 1,111,828 subjects were included. Of these subjects, 36,857 had urolithiasis. The male-to-female ratio was 1.57:1, and total incidence rate was 3.27 per 1,000 person-years (1,000p-yrs). The annual incidence was lowest in 2013 (3,138 patients) and highest in 2005 (3,751 patients). Incidence rate by diagnostic code was highest in ureter stone only (2.49 per 1,000p-yrs) and was lowest in kidney and ureter stone both (0.17 per 1,000p-yrs). Prevalence gradually increased from 3,172 in 2002 and 5,758 in 2013. Jeollanam-do had the highest incidence rate of 3.70 persons per 1,000p-yrs, and Jeju had the lowest rate of 2.84 persons per 1,000p-yrs. In gender analysis, Daegu had the highest incidence (4.56) in males, Jeollanam-do had the highest incidence (3.20) in females.

Conclusions

Annual incidence remained stable, whereas prevalence gradually increased. The incidence in male was 1.57 times higher than female, and the peak incidence age was 45–49 years, with the highest incidence occurring in Jeollanam-do and the lowest in Jeju.

The Effect of Thiazide and Potassium Citrate Use on the Health Related Quality of Life of Patients with Urolithiasis

PURPOSE

To our knowledge it is unknown whether the benefits of medical management of urolithiasis outweigh the potential side effects of the medications used, including potassium citrate and thiazide diuretics. Therefore, we evaluated the relationship between potassium citrate or thiazides and overall stone related health related quality of life.

MATERIALS AND METHODS

Cross-sectional data were obtained on stone forming enrollees in the North American Stone Quality of Life Consortium. We used the WISQOL (Wisconsin Stone Quality of Life) questionnaire to compare health related quality of life between patients treated and not treated with potassium citrate or thiazide type diuretics. Additionally, the likelihood of gastrointestinal complaints was compared between those prescribed and not prescribed potassium citrate. The likelihood of fatigue and sexual complaints was also compared in those prescribed and not prescribed thiazides.

RESULTS

Of the 1,511 subjects, including 787 males and 724 females, 279 were on potassium citrate and 238 were on thiazides at study enrollment. Patients prescribed potassium citrate had higher health related quality of life in each domain vs those not prescribed potassium citrate (p <0.001). Patients prescribed thiazides had higher health related quality of life in each domain compared to those not prescribed thiazide (all p <0.01). Those prescribed potassium citrate were less likely than those not prescribed potassium citrate to report nausea, stomach upset or cramps (OR 0.57, p <0.001). Patients prescribed thiazides were less likely than those not prescribed thiazides to report fatigue (OR 0.63, p = 0.004) or reduced sexual interest and/or activity (OR 0.64, p = 0.005).

CONCLUSIONS

Among stone formers the use of potassium citrate and thiazides was associated with better health related quality of life across all WISQOL domains without an increased likelihood of gastrointestinal complaints and fatigue or sexual complaints, respectively. These findings may be useful when counseling patients regarding the initiation of potassium citrate or thiazides for medical management of nephrolithiasis.

Variability of renal colic management and outcomes in two Canadian cities

BACKGROUND

Some centres favour early intervention for ureteral colic while others prefer trial of spontaneous passage, and relative outcomes are poorly described. Calgary and Vancouver have similar populations and physician expertise, but differing approaches to ureteral colic. We studied 60-day hospitalization and intervention rates for patients having a first emergency department (ED) visit for ureteral colic in these diverse systems.

METHODS

We used administrative data and structured chart review to study all Vancouver and Calgary patients with an index visit for ureteral colic during 2014. Patient demographics, arrival characteristics and triage category were captured from ED information systems, while ED visits and admissions were captured from linked regional hospital databases. Laboratory results were obtained from electronic health records and stone characteristics were abstracted from diagnostic imaging reports. Our primary outcome was hospitalization or urological intervention from 0 to 60 days. Secondary outcomes included ED revisits, readmissions and rescue interventions. Time to event analysis was conducted and Cox Proportional Hazards modelling was performed to adjust for covariate imbalance.

RESULTS

We studied 3283 patients with CT-defined stones. Patient and stone characteristics were similar for the cities. Hospitalization or intervention occurred in 60.9% of Calgary patients and 31.3% of Vancouver patients (p<0.001). Calgary patients had higher index intervention rates (52.1% v. 7.5%), and experienced more ED revisits and hospital readmissions during follow-up. The data suggest that outcome events were associated with overtreatment of small stones in one city and undertreatment of large stones in the other.

CONCLUSIONS

An early interventional approach was associated with higher ED revisit, hospitalization and intervention rates. If these events are markers of patient disability, then a less interventional approach to small stones and earlier definitive management of large stones may reduce system utilization and improve outcomes for patients with acute ureteral colic.

Validation of the Turkish version of the Wisconsin stone-quality of life questionnaire

OBJECTIVE

We validated the Turkish version of the Wisconsin Stone-Quality of Life (WISQoL) questionnaire for male and female patients with kidney stones.

MATERIAL AND METHODS

The Turkish version of the WISQoL questionnaire was developed following a well-established multistep process. A total of 84 patients with kidney stones completed the Turkish WISQoL questionnaire, including the other validated questionnaires as The Short Form Health Survey (SF-36 v2) and Beck's Depression Inventory. Patients completed questionnaires before percutaneous nephrolithotomy (PNL) surgery as well as 2-4 weeks after surgery. Reliability was evaluated by internal consistency (tested by Cronbach's alfa) and test-retest reliability between week 2 and 4 (tested by Spearman correlation). Domain structures were examined by interdomain correlations using Spearman correlation coefficient. Convergent validity was assessed by correlating the scores of general health domain to the SF-36 v2, and the scores of emotional impact domain to the Beck's Depression Inventory questionnaire. Sensitivity to change was assessed by comparing scores before and after PNL surgery with the Wilcoxon signed rank test. Discriminant validity was evaluated by comparing the results of patients 2 and 4 weeks after surgery with Wilcoxon-rank sum tests.

RESULTS

The Turkish version of the WISQoL demonstrates good internal consistency (Cronbach's α=0.72-0.78) and test-retest reliability (p>0.05). Inter-domain associations within the WISQOL showed a substantial correlation between various WISQoL domains, indicating a high conceptual relationship between the domains. Also, the Turkish version of the WISQoL showed convergent validity with the corresponding validated questionnaires (Spearman's rho correlation coefficient=0.44-0.78). All domains of the WISQoL showed significant sensitivity to change (p≤0.001).

CONCLUSION

The Turkish version of the WISQoL is a generally reliable instrument that can be self-administered by Turkish patients with kidney stones in clinical and research settings. Further clinical studies in Turkish settings would be useful to provide powerful data on sensitivity to change.

In vitro feasibility of next generation non-linear beamforming ultrasound methods to characterize and size kidney stones

Ultrasound imaging for kidney stones suffers from poorer sensitivity, diminished specificity, and overestimation of stone size compared to computed tomography (CT). The purpose of this study was to demonstrate in vitro feasibility of novel ultrasound imaging methods comparing traditional B-mode to advanced beamforming techniques including plane wave synthetic focusing (PWSF), short-lag spatial coherence (SLSC) imaging, mid-lag spatial coherence (MLSC) imaging with incoherent compounding, and aperture domain model image reconstruction (ADMIRE). The ultrasound techniques were evaluated using a research-based ultrasound system applied to an in vitro kidney stone model at 4 and 8 cm depths. Stone diameter sizing and stone contrast were compared among the different techniques. Analysis of variance was used to analyze the differences among group means, with p < 0.05 considered significant, and a Student's t test was used to compare each method with B-mode, with p < 0.0025 considered significant. All stones were detectable with each method. MLSC performed best with stone sizing and stone contrast compared to B-mode. On average, B-mode sizing error ± SD was > 1 mm (1.2 ± 1.1 mm), while those for PWSF, ADMIRE, and MLSC were < 1 mm (- 0.3 ± 2.9 mm, 0.6 ± 0.8, 0.8 ± 0.8, respectively). Subjectively, MLSC appeared to suppress the entire background thus highlighting only the stone. The ADMIRE and SLSC techniques appeared to highlight the stone shadow relative to the background. The detection and sizing of stones in vitro are feasible with advanced beamforming methods with ultrasound. Future work will include imaging stones at greater depths and evaluating the performance of these methods in human stone formers.

Quality of life and urolithiasis: the patient - reported outcomes measurement information system (PROMIS)

Background:

With a high rate of recurrence, urolithiasis is a chronic disease that impacts quality of life. The Patient Reported Outcomes Measurement Information System is an NIH validated questionnaire to assess patient quality of life. We evaluated the impact of urolithiasis on quality of life using the NIH-sponsored PROMIS-43 questionnaire.

Materials and Methods:

Patients reporting to the kidney stone clinic were interviewed to collect information on stone history and demographic information and were asked to complete the PROMIS-43 questionnaire. Quality of life scores were analyzed using gender and age matched groups for the general US population. Statistical comparisons were made based on demographic information and patient stone history. Statistical significance was P<0.05.

Results:

103 patients completed the survey. 36% of respondents were male, the average age of the group was 52 years old, with 58% primary income earners, and 35% primary caregivers. 7% had never passed a stone or had a procedure while 17% passed 10 or more stones in their lifetime. Overall, pain and physical function were worse in patients with urolithiasis. Primary income earners had better quality of life while primary caregivers and those with other chronic medical conditions were worse. Patients on dietary and medical therapy had better quality of life scores.

Conclusions:

Urolithiasis patients subjectively have worse pain and physical function than the general population. The impact of pain on quality of life was greatest in those patients who had more stone episodes, underscoring the importance of preventive measures. Stone prevention measures improve quality of life.

Improving Drainage After Percutaneous Nephrolithotomy Based on Health-Related Quality of Life: A Prospective Randomized Study

PURPOSE

The impact of drainage type after percutaneous nephrolithotomy (PCNL) on the health-related quality of life (HRQoL) has been rarely studied. We conducted a prospective randomized study to evaluate the differences in HRQoL among patients who received different drainage types.

METHODS

A total of 90 patients who underwent PCNL were randomized into three groups to receive a nephrostomy tube (Group 1), a Double-J (JJ) stent (Group 2), and an open-ended ureteral catheter (Group 3) after PCNL, respectively. We compared the perioperative characteristics, surgical outcomes, and HRQoL using Wisconsin Stone Quality of Life (WiSQoL) questionnaire among three groups.

RESULTS

There were no significant differences in patients' characteristics such as age, gender ratio, body mass index, stone burden, and so on. Majority of the surgical outcomes (operative time, estimated blood loss, hemoglobin drop, postoperative complications, and stone-free rate) were also comparable, except for the duration of hospitalization, visual analog scale, and analgesic required. The preoperative WiSQoL scores were similar among the three groups, but significant differences occurred postoperation (Groups 1, 2, and 3, 122.0 vs 105.6 vs 124.4, p < 0.001). Besides, patients in Group 2 had lower willingness (Groups 1, 2, and 3, 86.7% vs 70.0% vs 96.7%, p = 0.02) to undergo the same procedure as future treatment, if needed.

CONCLUSIONS

Our study suggested that the drainage types after PCNL using a nephrostomy tube or a JJ stent or an open-ended ureteral catheter were equally safe and efficacious, but patients who received a nephrostomy tube or an open-ended ureteral catheter had better HRQoL.

A Complete World Literature Review of Quality of Life (QOL) in Patients with Kidney Stone Disease (KSD)

Purpose of Review

The purpose of this study was to review the current evidence for quality of life (QOL) in patients with kidney stone disease (KSD).

Recent Findings

A review of literature from inception to May 2016 for all prospective English language articles on QOL in patients with KSD was done. QOL studies post urological procedures or ureteric stents were excluded. Nine studies (1570 patients) were included of which most (n = 6) used the SF-36 QOL tool. Overall, seven of the nine studies demonstrated a lower QOL in patients with KSD. Bodily pain and general health were significantly lower in patients with KSD compared to their control groups.

Summary

Patients with KSD have an overall lower QOL with most impact on bodily pain and general health domains. Compared to the scale of patients suffering from KSD, more work needs to be done in measuring QOL both in terms of ‘Stone specific’ QOL measuring tools and the quality/number of studies in this field.

Kidney stones

Kidney stones are mineral deposits in the renal calyces and pelvis that are found free or attached to the renal papillae. They contain crystalline and organic components and are formed when the urine becomes supersaturated with respect to a mineral. Calcium oxalate is the main constituent of most stones, many of which form on a foundation of calcium phosphate called Randall's plaques, which are present on the renal papillary surface. Stone formation is highly prevalent, with rates of up to 14.8% and increasing, and a recurrence rate of up to 50% within the first 5 years of the initial stone episode. Obesity, diabetes, hypertension and metabolic syndrome are considered risk factors for stone formation, which, in turn, can lead to hypertension, chronic kidney disease and end-stage renal disease. Management of symptomatic kidney stones has evolved from open surgical lithotomy to minimally invasive endourological treatments leading to a reduction in patient morbidity, improved stone-free rates and better quality of life. Prevention of recurrence requires behavioural and nutritional interventions, as well as pharmacological treatments that are specific for the type of stone. There is a great need for recurrence prevention that requires a better understanding of the mechanisms involved in stone formation to facilitate the development of more-effective drugs.

Effect of renal insufficiency on stone recurrence in patients with urolithiasis

The study was designed to assess the relationship between glomerular filtration rate (GFR) and urinary stone-forming constituents, and to assess the effect of renal insufficiency on stone recurrence risk in first stone formers (SF). Baseline serum creatinine levels were obtained, and renal insufficiency was defined as creatinine clearance ≤60 mL/min (Cockroft-Gault). This retrospective case-control study consists of 342 first SF; 171 SF with normal renal function were selected with 1:1 propensity scores matched to 171 SF with renal insufficiency. Urinary metabolic evaluation was compared to renal function. GFR was positively correlated with urinary calcium, uric acid, and citrate excretion. Subjects with renal insufficiency had significantly lower urinary calcium, uric acid, and citrate excretion than those with normal renal function, but not urine volume. With regard to urinary metabolic abnormalities, similar results were obtained. SF with renal insufficiency had lower calcium oxalate supersaturation indexes and stone recurrence rates than SF with normal renal function. Kaplan-Meier curves showed similar results. In conclusion, GFR correlates positively with urinary excretion of stone-forming constituents in SF. This finding implies that renal insufficiency is not a risk factor for stone recurrence.