Vascular calcification in kidney stone formers: the impact of age and stone composition.

An increased prevalence of vascular calcification (VC) has been reported in kidney stone formers (KSFs), along with an elevated cardiovascular risk. The aim of the current study is to assess whether VC in these patients develops at a younger age and is influenced by stone composition. This single-center, matched case-control study included KSFs with uric acid or calcium oxalate stones (diagnosed based on stone analysis) and age- and sex-matched controls without a history of nephrolithiasis. The prevalence and severity of abdominal aortic calcification (AAC) and bone mineral density (BMD) were compared between KSFs and non-KSFs. In total, 335 patients were investigated: 134 with calcium oxalate stones, 67 with uric acid stones, and 134 controls. Overall, the prevalence of AAC was significantly higher among calcium stone formers than among the controls (67.9% vs. 47%, p = 0.002). In patients under 60 years of age, those with calcium oxalate stones exhibited both a significantly elevated AAC prevalence (61.9% vs. 31.3%, p = 0.016) and severity (94.8 ± 15.4 vs. 30.3 ± 15.95, p = 0.001) compared to the controls. Within the age group of 40-49, osteoporosis was identified only in the KSFs. Multivariate analysis identified age, smoking, and the presence of calcium stones as independent predictors of AAC. This study highlights that VC and osteoporosis occur in KSFs at a younger age than in non-stone-formers, suggesting potential premature VC. Its pathogenesis is intriguing and needs to be elucidated. Early evaluation and intervention may be crucial for mitigating the cardiovascular risk in this population.

Association between oxidative balance score and kidney stones: data from the national health and nutrition examination survey (NHANES).

PURPOSE: Some studies have found that the pathological formation of kidney stones is closely related to injury and inflammatory response. Behaviors such as dietary composition, physical activity, obesity and smoking can all affect the body's oxidative stress levels. In order to evaluate the effects of various diets and lifestyles on the body's oxidative and antioxidant systems, an oxidative balance score was developed. To investigate whether the OBS is associated with the development of kidney stones. METHODS: Data were taken from the National Health and Nutrition Examination Survey (NHANES) from 2007-2018, followed by retrospective observational studies. The association between kidney stones and OBS was analyzed using survey-weighted logistic regression by adjusting for demographics, laboratory tests, and medical comorbidity covariates. The oxidative balance score is calculated by screening 16 nutrients and 4 lifestyle factors, including 5 prooxidants and 15 antioxidants, based on prior information about the relationship between oxidation levels in the body and nutrients or lifestyle factors. RESULTS: A total of 26,786 adult participants were included in the study, of which 2,578, or 9.62%, had a history of nephrolithiasis. Weighted logistic regression analysis found an association between OBS and kidney stones. In the fully tuned model, i.e., model 3, the highest quartile array of OBS was associated with the lowest quartile array of OBS (OR = 0.73 (0.57, 0.92)) with the risk of kidney stone (p = 0.01), and was statistically significant and remained relatively stable in each model. At the same time, the trend test in the model is also statistically significant. With the increase of OBS, the OR value of kidney stones generally tends to decrease. CONCLUSIONS: There is an inverse correlation between OBS and kidney stone disease. At the same time, higher OBS suggests that antioxidant exposure is greater than pro-oxidative exposure in diet and lifestyle, and is associated with a lower risk of kidney stones.

Association between chinese visceral adiposity index and risk of kidney stones in a health screening population: an ultrasonography based cross-sectional study.

BACKGROUND: Obesity is an important risk factor for kidney stones(KS). Chinese Visceral Adiposity Index (CVAI), as a specific indicator for visceral obesity in the Chinese population, can more accurately assess the visceral fat content in Chinese individuals compared to Visceral Adiposity Index (VAI). However, the association between CVAI and risk for KS has not been studied. METHODS: A total of 97,645 participants from a health screening cohort underwent ultrasound examinations for the diagnosis of kidney stones, along with measurements of their CVAI. Logistic regressions were utilized to determine the relationship between different quartiles of CVAI and the incidence of kidney stones. Simultaneously, subgroup analysis and the computation of dose-response curves were employed to pinpoint susceptible populations. RESULTS: Among the participants, 2,888 individuals (3.0%) were diagnosed with kidney stones. The mean CVAI values ± standard deviation for the four groups were: Q1 (18.42 ± 19.64), Q2 (65.24 ± 10.39), Q3 (98.20 ± 9.11), and Q4 (140.40 ± 21.73). In the fully adjusted multivariable model, CVAI was positively correlated with urolithiasis (OR = 1.001; 95% CI = 1.000, 1.002). Compared with the first quartile of CVAI, the population in the fourth quartile of CVAI had a higher prevalence of kidney stones (OR = 1.231; 95% CI = 1.066, 1.415). Through subgroup analysis, a positive correlation between CVAI and the risk of kidney stones was found in non-smokers (OR = 1.001, 95%CI:1.000, 1.002), non-drinkers (OR = 1.001, 95%CI:1.000, 1.002), non-hypertensive subgroups (OR = 1.003, 95%CI:1.002, 1.003), and non-diabetes subgroups (OR = 1.001, 95%CI:1.000, 1.002). CONCLUSION: The findings suggest that CVAI could be a reliable and effective biomarker for assessing the potential risk of kidney stone prevalence, with significant implications for the primary prevention of kidney stones and public health.

Association Between Physical Activity and the Prevalence of Kidney Stones in American Adults: Results From a Multiyear National Survey.

OBJECTIVE: To investigate the association between physical activity (PA) and the prevalence of kidney stones. METHODS: A cross-section study was conducted using data from National Health and Nutrition Examination Survey 2007-2018. PA was evaluated based on the Global Physical Activity Questionnaire. Multivariable logistic regression was performed to elucidate the association between PA (patterns, intensity, duration, and frequency of moderate and vigorous PA) and the prevalence of kidney stones after adjusting for potential confounders. Stratified and interaction analyses were conducted to detect potential effect modifiers. In addition, PA was assessed using metabolic equivalent and physical volume, and followed the regression above. Water intake was obtained from the day 2 dietary recall and was included in the sensitivity analysis. RESULTS: A total of 34,390 participants were included in the analysis. The multivariable logistic regression revealed that individuals who engaged in moderate PA for 30-60 minutes per day had a significant inverse association with the prevalence of kidney stones in the fully adjusted model (odds ratio=0.804, 95% confidence interval 0.700 to 0.923), while no more significant finding was observed for other PA parameters. Interaction and stratified analyses indicated no covariate modifying the association. The results above were robust in the sensitivity analysis. CONCLUSION: The duration of moderate PA (30-60 min/d) is inversely associated with the prevalence of kidney stones, while no more significant association was observed between other PA parameters (including patterns, intensity, duration, and frequency of vigorous PA, frequency of moderate PA) and kidney stones.

Composition analysis of renal and ureteral calculi in a single center in northern China in the past decade.

The current report aimed to evaluate the characteristics of stone composition in 3637 renal and ureteral calculi patients in a single center while clarifying its relationship with sex, age, and time. Out of 3637 cases of upper urinary tract stones, stone specimens were analyzed retrospectively. There were 2373 male patients aged 6 months-87 years, with an average age of 44.73 ±â€…15.63 years, and 1264 female patients aged 4 months-87 years, with an average age of 46.84 ±â€…16.00 years. The male-female ratio was 1.88:1. Five hundred twelve patients had ureteral calculi, and 3125 had renal calculi. The SPSS software helped analyze the relationship between renal and ureteral calculi composition and sex, age, and time. Stone composition demonstrated 2205 cases of calcium oxalate stones (60.6%), 518 carbonate apatite (14.2%), 386 uric acids (10.6%), 232 magnesium ammonium phosphate (6.4%), 117 calcium phosphate (3.2%), 76 cystine (2.1%), 47 sodium urate (1.3%), 31 others (0.9%), and 25 ammonium urate (0.7%) cases. The overall male-to-female sex ratio was 1.88:1. Stones in the upper urinary tract were significantly more frequent in men than in women between the ages of 31 and 60. However, such stones were significantly more frequent in women than men over 80 (P < .05). Cystine, Sodium urate, Carbonated apatite, and uric acid indicated significant differences between different age categories (all P < .001). Stone composition analyses revealed that the frequency of calcium oxalate calculi has increased annually, while cystine and carbonated apatite incidences have dropped annually over the past decade. The components of renal and ureteral calculi vary significantly based on age and sex, with calcium oxalate calculi being more frequent in men while magnesium ammonium phosphate stones are more frequent in female patients. The age between 31 and 60 years is the most prevalent for renal and ureteral calculi in men and women.

Long-term complications of permanent hypoparathyroidism in adults: prevalence and associated factors.

INTRODUCTION: Patients with Chronic hypoparathyroidism (CHPT) receiving conventional treatment are exposed to several long-term complications including basal ganglia calcifications, posterior subcapsular cataract, kidney stones, and renal insufficiency. The aim of this study was to assess the prevalence and the associated factors of these complications in patients with CHPT. METHODS: We conducted a cross-sectional study including 58 patients with CHPT. All participants underwent physical examination, biochemical assessment (total serum calcium, serum phosphorus, serum albumin, intact-PTH, serum magnesium, 25-hydroxy-vitamin D, serum creatinine, thyroid stimulating hormone (TSH), and 24-hour urinary calcium), slit lamp examination, brain computed tomography scan (CT-scan), and renal ultrasound. RESULTS: Participants had a mean age of 52.6 ± 16.4 years and a gender ratio (women/men) of 3.5. Fahr syndrome, cataract, urolithiasis, and renal failure were found in 55%, 62%, 12%, and 17% of cases, respectively. CHPT duration >15 years (Adjusted-OR = 43.1, 95-CI: 2.63-703.06, p = 0.008) and poor adherence to treatment (Adjusted-OR = 8.04, 95%-CI: 1.52-42.42, p = 0.014) were independently associated with the risk of Fahr syndrome. Age >55 years (adjusted-OR = 5.07, 95-CI: 1.10-23.42, p = 0.037), disease duration >15 years (adjusted-OR = 20.21, 95-CI: 1.54-265.84, p = 0.022), and magnesium level <0.8 mmol/l (adjusted-OR = 36.46, 95-CI: 3.75-354.08, p = 0.002) were independently associated with the risk of subcapsular cataract. Only hypercalciuria (Adjusted-OR = 21.27, 95-CI: 2.31-195.91, p = 0.007) was an independent risk factor for kidney stones. Renal failure was not associated with kidney stones (p = 1). However, creatinine clearance was negatively correlated with age (r = -0.784; p < 10-3) and disease duration (r = -0.352; p = 0.007). CONCLUSION: Our results revealed high prevalences of neurological, ocular, and renal complications in patients with CHPT and emphasized the importance of regular biological monitoring, therapeutic adjustments, screening, and adherence to treatment in the prevention of these complications.

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.

A positive association between BMI and kidney stones among the diabetic population: a cross-sectional study from NHANES.

BACKGROUND: In the past, research has shown that a higher body mass index (BMI) is one of the variables that increase the likelihood of kidney stones; however, no studies have found a connection between the two in the type II diabetic population. The purpose of this research is to reveal the association between BMI and kidney stones in the type II diabetic population. METHODS: We selected demographic data, laboratory data, lifestyle, and medical history from the NHANES. Specifically includes age, gender, systemic immune-inflammation index (SII), poverty income rate (PIR), body mass index (BMI), kidney stones, education, coronary artery disease, smoking, and drinking. RESULTS: BMI and kidney stones were shown to have a positive association in type II diabetics (blood sugar level > 7.0 mmol/L or diagnosed by a doctor) (OR = 1.021, 95% CI 1.008-1.033, P = 0.001), even after controlling for factors, such as age, gender, race, education level, coronary heart disease, smoking, and drinking. The subgroup analysis revealed a more significant positive association among the 67-80 years, female and Non-Hispanic White population. CONCLUSIONS: There is a positive correlation between BMI and kidney stones among the type II diabetic population.

The association between C-reactive protein levels and the risk of kidney stones: a population-based study.

OBJECTIVES: The relationship between C-reactive protein (CRP) and the risk of developing kidney stones is unclear, and we aimed to assess the association between CRP and kidney stones in US adults. METHODS: We used data from NHANES 2007-2010, and we excluded participants who were under 18 years of age and lacked data on CRP and kidney stones. Finally, we included a total of 11,033 participants and performed weighted multivariate regression analysis and subgroup analysis to assess the independent relationship between CRP and kidney stones. RESULTS: The mean prevalence of kidney stones among the participants was 9.8%. Notably, as CRP levels increased, the prevalence of kidney stones exhibited a corresponding rise across quartiles (Kidney stones: Quartile 1: 7.59%; Quartile 2: 8.77%; Quartile 3: 9.64%; Quartile 4: 10.89%). CRP was positively associated with the risk of kidney stones (Model 1: OR = 1.09, 95% CI: 1.01-1.18, p = 0.03; Model 2: OR = 1.09, 95% CI: 1.00-1.18, p = 0.03, Model 3: OR = 1.14, 95%CI: 1.02-1.26, p = 0.04). Participants in the highest CRP quartile experienced a 69% increased risk of kidney stones compared to those in the lowest quartile (OR = 1.64, 95% CI: 1.04-2.59, p = 0.03). Notably, interaction tests revealed that gender, BMI, diabetes, hypertension, CKD and smoking or alcohol consumption status did not significantly influence the association between CRP and kidney stones. CONCLUSIONS: Our findings reveal a significant association between higher CRP levels and an increased risk of kidney stones. In clinical practice, heightened awareness of CRP as a potential biomarker could aid in risk assessment and management strategies for kidney stone patients.

Prevalence of urolithiasis in China: a systematic review and meta-analysis.

OBJECTIVE: To estimate the pooled prevalence, as well as the spatial and temporal distribution, of urolithiasis among subjects in China. MATERIALS AND METHODS: We conducted a comprehensive search of both Chinese and English databases to retrieve literature pertaining to the prevalence of urolithiasis in the indigenous Chinese population. A random-effects meta-analysis model was employed to calculate the pooled prevalence of urolithiasis. Subgroup analyses were conducted based on factors such as time, region, gender, and sample size. Prevalence and spatial distribution maps were created based on provinces and latitude/longitude coordinates. RESULTS: A total of 46 studies conducted in 22 provinces across China were included in this meta-analysis and the pooled prevalence of urolithiasis, kidney stones, ureteric calculi, urethral and bladder stones were 8.1% (95% confidence interval [CI] 5.6-11.1%), 7.8% (95% CI 5.8-10.0%), 3.2% (95% CI 0.6-5.7%), 0.5% (95% CI 0.1-0.9%). Most of the urolithiasis prevalence screening in China was concentrated between 100° E and 120° E, with higher rates observed in low latitude areas. Subgroup analysis of kidney stones revealed that Guangdong (12.7%) and Guangxi (10.3%) had the highest prevalence, with the eastern developed area exhibiting higher rates compared to the west. The prevalence in males was higher than in females (odds ratio 1.67, 95% CI 1.46-1.92), although the gender gap has significantly reduced since 2006. Moreover, a greater sample size is associated with a decreased prevalence of urolithiasis. CONCLUSIONS: The prevalence of urolithiasis is increasing in China, and there are noteworthy regional or provincial disparities in occurrence. It is worth noting that the current number of screening studies in some areas is insufficient. Additional investigations with appropriate sample sizes should be supplemented in time.

Kidney stones in renal transplant recipients: A systematic review.

INTRODUCTION: Lithiasis in renal graft recipients might be a dangerous condition with a potential risk of organ function impairment. EVIDENCE ACQUISITION: A systematic literature search was conducted through February 2023. The primary objective was to assess the incidence of lithiasis in kidney transplant (KT) recipients. The secondary objective was to assess the timing of stone formation, localization and composition of stones, possible treatment options, and the incidence of graft loss. EVIDENCE SYNTHESIS: A total of 41 non-randomized studies comprising 699 patients met our inclusion criteria. The age at lithiasis diagnosis ranged between 29-53 years. Incidence of urolithiasis ranged from 0.1-6.3%, usually diagnosed after 12 months from KT. Most of the stones were diagnosed in the calyces or in the pelvis. Calcium oxalate composition was the most frequent. Different treatment strategies were considered, namely active surveillance, ureteroscopy, percutaneous/combined approach, or open surgery. 15.73% of patients were submitted to extracorporeal shock wave lithotripsy (ESWL), while 26.75% underwent endoscopic lithotripsy or stone extraction. 18.03% of patients underwent percutaneous nephrolithotomy whilst 3.14% to a combined approach. Surgical lithotomy was performed in 5.01% of the cases. Global stone-free rate was around 80%. CONCLUSIONS: Lithiasis in kidney transplant is a rare condition usually diagnosed after one year after surgery and mostly located in the calyces and renal pelvis, more frequently of calcium oxalate composition. Each of the active treatments is associated with good results in terms of stone-free rate, thus the surgical technique should be chosen according to the patient's characteristics and surgeon preferences.

Comparison of Class-Specific Side Effects Across Preventative Pharmacologic Therapies for Kidney Stone Disease.

INTRODUCTION: Clinical guidelines recommend monitoring for metabolic derangements while on preventive pharmacologic therapy for kidney stone disease. The study objective was to compare the frequency of side effects among patients receiving alkali citrate, thiazides, and allopurinol. METHODS: Using claims data from working-age adults with kidney stone disease (2008-2019), we identified those with a new prescription for alkali citrate, thiazide, or allopurinol within 12 months after their index stone-related diagnosis or procedure. We fit multivariable logistic regression models, adjusting for cohort characteristics like comorbid illness and medication adherence, to estimate 2-year measured frequencies of claims-based outcomes of acute kidney injury, falls/hip fracture, gastritis, abnormal liver function tests/hepatitis, hypercalcemia, hyperglycemia/diabetes, hyperkalemia, hypokalemia, hyponatremia, and hypotension. RESULTS: Our cohort consisted of 1776 (34%), 2767 (53%), and 677 (13%) patients prescribed alkali citrate, thiazides, or allopurinol, respectively. Comparing unadjusted rates of incident diagnoses, thiazides compared to alkali citrate and allopurinol were associated with the highest rates of hypercalcemia (2.3% vs 1.5% and 1.0%, respectively, P = .04), hypokalemia (6% vs 3% and 2%, respectively, P < .01), and hyperglycemia/diabetes (17% vs 11% and 16%, respectively, P < .01). No other differences with the other outcomes were significant. In adjusted analyses, compared to alkali citrate, thiazides were associated with a higher odds of hypokalemia (OR=2.01, 95% CI 1.44-2.81) and hyperglycemia/diabetes (OR=1.52, 95% CI 1.26-1.83), while allopurinol was associated with a higher odds of hyperglycemia/diabetes (OR=1.34, 95% CI 1.02-1.75). CONCLUSIONS: These data provide evidence to support clinical guidelines that recommend periodic serum testing to assess for adverse effects from preventive pharmacologic therapy.

Dietary Magnesium Intake and Kidney Stone: The National Health and Nutrition Examination Survey 2011-2018.

BACKGROUND: The association between dietary magnesium intake (DMI) and kidney stone (KS) disease is not clear. AIM: To determine the association between DMI and prevalent KS disease defined as self-report of any previous episode of KS. METHODS: We examined The National Health and Nutrition Examination Survey (NHANES) 2011-2018 and used logistic regression analyses adjusting for demographics, BMI, histories of hypertension, diabetes, thiazide use, cigarette smoking, alcohol drinking, relevant dietary and supplemental intakes to determine the independent association between DMI and prevalent KS disease. RESULTS: A total of 19,271 participants were eligible for the final analysis, including 1878 prevalent KS formers. Mean DMI among stone formers was 295.4 mg/day, as compared to 309.6 mg/day among non-stone formers (p=0.02). Higher DMI was strongly associated with lower odds of prevalent KS disease in univariate analysis regardless of when DMI was analyzed as a continuous variable (OR=0.94, 95% CI: 0.89-0.99, p=0.02) or when the extreme quartiles of DMI were compared (OR=0.74, 95% CI: 0.60-0.92, p=0.007). In the multivariable-adjusted regression analysis, those in the highest quartile of DMI compared to the lowest quartile (≥379 mg vs. <205 mg) had significantly reduced odds of prevalent KS (OR=0.70, 95% CI: 0.52-0.93, p=0.01). When DMI was analyzed as a continuous variable, there was a trend toward reduced odds of prevalent KS disease with higher DMI (OR=0.92 per 100 mg, 95% CI: 0.84-1.01, p=0.07). CONCLUSIONS: Our study suggests that higher DMI is associated with a reduced risk of KS disease. Future prospective studies are needed to clarify the causal relationship between DMI and KS disease.

Incidence of Kidney Stones After Bariatric Surgeries: Comparing Roux-en-Y Gastric Bypass and Sleeve Gastrectomy.

INTRODUCTION/PURPOSE: The two most common procedures performed to treat obesity are Roux-En-Y gastric bypass (RNYGB) and laparoscopic sleeve gastrectomy (LSG). Due to changes in enteric absorption, bariatric surgery increases rates of nephrolithiasis. As population-based data are limited, we aimed to compare the incidence of kidney stones after RNYGB and LSG. MATERIALS AND METHODS: We queried Explorys (Cleveland, OH), a database that aggregated data from 26 healthcare systems. We identified patients who were newly diagnosed with nephrolithiasis 3, 6, and 12 months after their RNYGB or LSG. Additionally, a multivariate analysis was conducted to investigate the association of nephrolithiasis with RNYGB as compared to LSG. This analysis adjusted for other risk factors, including age above 65, male gender, Caucasian race, diabetes mellitus, hypertension, primary hyperparathyroidism, gout, and obesity. RESULTS: From 1999 to 2019, there were 11,480 patients who underwent RNYGB and 22,770 patients who underwent LSG. The incidence of nephrolithiasis in the RNYGB cohort at all three time points was higher than in the LSG cohort (3 months, 7.1% vs. 2.4%; 6 months, 6.6% vs. 2.0%; 1 year, 5.8% vs. 1.4%; P < 0.001). After the multivariate analysis, it was found that, though both RNYGB and LSG were independently associated with the development of nephrolithiasis, the risk of nephrolithiasis was higher in those who underwent RNYGB compared to those who underwent LSG (OR 1.594, 95% CI 1.494 to 1.701, P < 0.001). CONCLUSION: RNYGB is associated with a higher risk of nephrolithiasis when compared to LSG.

Causal effects of inflammatory bowel diseases on the risk of kidney stone disease: a two-sample bidirectional mendelian randomization.

BACKGROUND: Existing epidemiological observational studies have suggested interesting but inconsistent clinical correlations between inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), and kidney stone disease (KSD). Herein, we implemented a two-sample bidirectional Mendelian randomization (MR) to investigate the causal relationship between IBD and KSD. METHODS: Data on IBD and KSD were obtained from Genome-Wide Association Studies (GWAS) summary statistics and the FinnGen consortium, respectively. Strict selection steps were used to screen for eligible instrumental SNPs. We applied inverse variance weighting (IVW) with the fix-effects model as the major method. Several sensitivity analyses were used to evaluate pleiotropy and heterogeneity. Causal relationships between IBD and KSD were explored in two opposite directions. Furthermore, we carried out multivariable MR (MVMR) to obtain the direct causal effects of IBD on KSD. RESULTS: Our results demonstrated that CD could increase the risk of KSD (IVW: OR = 1.06, 95% CI = 1.03-1.10, p < 0.001). Similar results were found in the validation group (IVW: OR = 1.05, 95% CI = 1.01-1.08, p = 0.013) and in the MVMR analysis. Meanwhile, no evidence of a causal association between UC and KSD was identified. The reverse MR analysis detected no causal association. CONCLUSIONS: This MR study verified that CD plays a critical role in developing kidney stones and that the effect of UC on KSD needs to be further explored.

A population-based retrospective cohort study of surgical trends and outcomes of pediatric urolithiasis in Ontario, Canada (2002-2019).

INTRODUCTION: The worldwide incidence of pediatric urinary stone disease (PUSD) is increasing. However, there is no commensurate data on whether this translates to an increasing need for surgical intervention for PUSD, given the role of conservative management. OBJECTIVE: We aimed to evaluate the trends and outcomes of clinically significant PUSD, using administrative databases to identify patients surgically treated for PUSD. STUDY DESIGN: This retrospective population-based cohort study assessed the incidence and trends of surgically treated PUSD and outcomes in Ontario, Canada in patients <18 years of age who underwent their first PUSD procedure between 2002 and 2019 utilizing administrative databases held at the Institute of Clinical Evaluative Sciences (ICES). We assessed the incidence of surgically treated PUSD, demographics, initial surgical treatment and imaging modality, and risk factors for repeat intervention within 5 years. Statistical analyses summarized demographics, surgical trends, and logistic regression was used to identify risk factors for repeat surgical intervention. RESULTS: We identified 1149 patients (mean age 11.3 years), with 59.6% older than 12 years. There was a decrease in the number of PUSD procedures performed per year that was close to statistical significance (p = 0.059) and a trend towards increased utilization of ureteroscopy (URS) compared with Shockwave Lithotripsy (SWL). In addition, there was a significant increase in the proportion of females surgically treated with PUSD (p = 0.001). In the 706 patients followed for 5 years, 17.7% underwent a repeat procedure within 6 months, while 20.4% underwent a repeat procedure from 6-months to 5 years. Renal stone location (OR 2.79, 95% confidence interval (CI) 1.62-4.80, p = 0.0002) and index SWL (OR 1.66, 95% CI 1.20-2.31, p = 0.0025) were risk factors for repeat surgical intervention within the first 6-months. There was an increasing utilization of ultrasound (US) compared to computerized tomography (CT) (p = 0.0008). DISCUSSION: Despite the literature reporting increasing PUSD incidence, we observed a non-significant decrease in the number of surgical PUSD procedures performed. Exclusion of those treated conservatively may explain our results. The increase in the proportion of females treated reflects the narrowing gender gap in stone disease. A trend towards increased URS utilization was observed and re-intervention rates were similar to previous studies. CONCLUSION: The overall rate of surgically treated PUSD did not show an increasing trend in Ontario, Canada from 2002 to 2019. URS was the most common surgical treatment modality, with a corresponding decline in SWL rates. PUSD was associated with a high surgical re-intervention rate within 6 months.

Evaluation of risk factors for recurrent renal stone formation among Saudi Arabian patients: Comparison with first renal stone episode.

OBJECTIVES: We evaluated the baseline characteristics, and risk factors of renal stone recurrence among Saudi Arabian patients after successful primary stone treatment. MATERIALS AND METHODS: In this cross-sectional comparative study, we reviewed the medical records of patients who presented consecutively with a first renal stone episode from 2015 to 2021 and were followed-up by mail questionnaire, telephone interviews, and/or outpatient clinic visit. We included patients who achieved stone-free status after primary treatment. Patients were divided into two groups: group I (patients with first episode renal stone) and group Ⅱ (patients who developed renal stone recurrence). The study outcomes were to compare the demographics of both groups and to evaluate the risk factors of renal stone recurrence after successful primary treatment. We used Student's t-test, Mann Whitney test or chi-square (x2) to compare variables between groups. Cox regression analyses were used to examine the predictors. RESULTS: We investigated 1260 participants (820 males and 440 females). Of this number, 877 (69.6%) didn't develop renal stone recurrence and 383 (30.4%) had recurrence. Primary treatments were percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), extracorporeal shock wave lithotripsy (ESWL), surgery and medical treatment in 22.5%, 34.7%, 26.5%, 10.3%, and 6%, respectively. After primary treatment, 970 (77%) and 1011 (80.2%) of patients didn't have either stone chemical analysis or metabolic work-up, respectively. Multivariate logistic regression analysis revealed that male gender (OR: 1.686; 95% CI, 1.216-2.337), hypertension (OR: 2.342; 95% CI, 1.439-3.812), primary hyperparathyroidism (OR: 2.806; 95% CI, 1.510-5.215), low fluid intake (OR: 28.398; 95% CI, 18.158-44.403) and high daily protein intake (OR: 10.058; 95% CI, 6.400-15.807) were predictors of renal stone recurrence. CONCLUSIONS: Male gender, hypertension, primary hyperparathyroidism, low fluid intake and high daily protein intake increase the risk of renal stone recurrence among Saudi Arabian patients.

Association between metabolically healthy obesity and kidney stones: results from the 2011-2018 National Health and Nutrition Examination Survey.

Introduction: The risk of kidney stones in metabolically healthy obesity (MHO) individuals is largely unexplored. This study using percent body fat (%BF) to categorize obesity, to investigate the association between MHO as well as other metabolic syndrome-obesity combined phenotypes and kidney stones in a national representative population. Materials and methods: This cross-sectional study included 4,287 participants in the National Health and Nutrition Examination Survey from 2011 to 2018. Metabolically healthy status was defined as not having any component of metabolic syndrome or insulin resistance. Obesity was identified by %BF, which was measured and assessed by dual-energy x-ray absorptiometry (DXA) scan. Participants were cross-classified by metabolic health and obesity status. The outcome was self-report kidney stones. Multivariable logistic regression model was used to examine the association between MHO and kidney stones. Results: A total of 358 participants had kidney stones [weighted prevalence (SE): 8.61% (0.56%)]. The weighted prevalence (SE) of kidney stones in MHN, MHOW, and MHO groups was 3.13% (1.10%), 4.97% (1.36%), and 8.55% (2.09%), respectively. After adjusting for age, sex, race and ethnicity, education level, smoking status, alcohol consumption, physical activity, daily water intake, CKD stage 3-5, and hyperuricemia, MHO individuals (OR: 2.90, 95% CI: 1.18, 7.0) had a significantly higher risk of kidney stones than those with metabolically healthy normal weight. In metabolically healthy participants, a 5% increment in %BF was associated with a significantly higher risk of kidney stones (OR: 1.60, 95% CI: 1.20, 2.14). Furthermore, a nonlinear dose-response relationship between %BF and the kidney stones was observed in metabolically healthy participants (P for non-linearity = 0.046). Conclusion: Using %BF to define obesity, MHO phenotype was significantly associated with higher risks of kidney stones, suggesting that obesity can independently contribute to kidney stones in the absence of metabolic abnormalities and insulin resistance. Regarding kidney stones prevention, MHO individuals might still benefit from lifestyle interventions aimed at healthy body composition maintenance.

Association between alcohol consumption and kidney stones in American adults: 2007-2016 NHANES.

Purpose: To investigate the association between alcohol consumption and kidney stones in American adults. Materials and methods: National Health and Nutrition Examination Survey (NHANES) datasets from 2007 to 2016 were utilized. Participants with a history of kidney stones and alcohol consumption aged 20 or older were included. Weighted proportions and regression analysis were used to assess the association between alcohol consumption and kidney stones by adjusting age, gender, race, marital status, education, recreational activities, smoking, and several comorbidities. Results: Eleven population samples (Q1-Q11) were included from the NHANES dataset based on 11 questions compiled from the Alcohol Use Questionnaire (ALQ). In the fully adjusted regression model, none of these 11 samples demonstrated a significant association with urolithiasis, that is, alcohol consumption was not significantly associated with the incidence of kidney stones, even among heavy drinkers. Conclusion: Alcohol consumption is not significantly associated with the prevalence of kidney stones. This finding requires a more adequate sample size and a more detailed review of the history of kidney stones to be further verified.

The relationship between patients' kidney stone type and demographics in Israel: analysis of 10 K patients.

PURPOSE: To analyze urinary stone composition in Israel and assess the effects of key demographic parameters (gender, age, socioeconomic status, ethnicity, medical history and geographic region) on stone composition. METHODS: A retrospective review was conducted of stone analysis of 10,633 patients from an HMO Israeli database analyzed by a central laboratory from 2014 to 2019 and subjected to Fourier-transform infrared spectroscopy. Associations between stone composition and different demographic parameters were determined using the Chi-square test. RESULTS: Calcium oxalate (CaOx) monohydrate accounted for 51.9% of the stones. Of the total sample, 5776 stones had one single component (54%), whereas 4857 (46%) had mixed components. Men had a higher frequency of CaOx stones (89.6% vs. 85.6%), whereas women had a higher frequency of calcium phosphate, infection, and cystine stones (27.2%, 17.7%, and 0.9% vs. 17.2%, 7.5%, and 0.5%, respectively). Cystine stones were more abundant in Arabs (1.2% vs. 0.5% in the Jewish population). Lower socioeconomic status was associated with a higher prevalence of calcium phosphate, uric acid, and infection stones and a lower prevalence of CaOx stones. Uric acid stones were associated with medical conditions such as diabetes, hypertension, ischemic heart disease, and obesity (28.3%, 24.9%, 25.7%, and 22.6% vs. 9.6%, 8.4%, 12.3%, and 10.3%, respectively). CONCLUSIONS: Stone types were highly influenced by patients' demographics. COM was the most common stone component in either pure or complex form. UA stone prevalence was found to increase with age and was associated with medical conditions such as diabetes, hypertension, ischemic heart disease, and obesity.