Increased risk of diabetes in patients with urinary calculi: a 5-year followup study

Examination of nutritional factors associated with urolithiasis risk in plant based meat alternatives marketed to children and infants

INTRODUCTION

The global prevalence of pediatric nephrolithiasis continues to rise amidst increased sodium and animal protein intake. Plant-based meat alternatives (PBMAs) have recently gained popularity due to health benefits, environmental sustainability, and increased retail availability. PBMAs have the potential to reduce the adverse metabolic impact of animal protein on kidney stone formation. We analyzed PBMAs targeted to children to characterize potential lithogenic risk vs animal protein.

METHODS

We performed a dietary assessment using a sample of PBMAs marketed to or commonly consumed by children and commercially available at national retailers. Nutrient profiles for PBMAs were compiled from US Department of Agriculture databases and compared to animal protein sources using standardized serving sizes. We also analyzed nutrient profiles for plant-based infant formulas against typical dairy protein-based formulas. Primary protein sources were identified using verified ingredient lists. Oxalate content was extrapolated from dietary data sources.

RESULTS

A total of 41 PBMAs were analyzed: chicken (N = 18), hot dogs (N = 3), meatballs (N = 5), fish (N = 10), and infant formula (N = 5). Most products (76%) contained a high-oxalate ingredient as the primary protein source (soy, wheat, or almond). Average oxalate content per serving was substantially higher in these products (soy 11.6 mg, wheat 3.8 mg, almond 10.2 mg) vs animal protein (negligible oxalate). PBMAs containing pea protein (24%) had lower average oxalate (0.11 mg). Most PBMAs averaged up to six times more calcium and three times more sodium per serving compared to their respective animal proteins. Protein content was similar for most categories.

CONCLUSIONS

Three-quarters of the examined plant-based meat products for children and infants contain high-oxalate protein sources. Coupled with higher per-serving sodium and calcium amounts, our findings raise questions about possible lithogenic risk in some PBMAs, and further studies are needed to assess the relationship between PBMAs and nephrolithiasis.

A functional MMP-9-1562C>T polymorphism, MMP-9 serum levels and nephrolithiasis risk in a southern Chinese population

Background

The role of matrix metalloproteinase 9 (MMP-9) in the pathophysiology of chronic kidney disease (CKD), which is associated with a nearly two-fold greater risk for urinary calculi compared to people without CKD, has been demonstrated. The aim of the research is to evaluate the association between MMP-9-1562C>T polymorphism, MMP-9 serum levels and nephrolithiasis risk.

Methods

A hospital-based case-control study involving 302 kidney stone patients and 408 controls without kidney stone from southern China was conducted. Sanger sequencing was used to genotype the MMP-9-1562C>T polymorphism. The serum MMP-9 was measured in 105 kidney stone patients and 77 controls by enzyme-linked immunosorbent assay.

Results

Compared to the control group, the CT genotype was more frequent in nephrolithiasis patients (adjusted OR = 1.60, 95% CI = 1.09-2.37: the risk of developing nephrolithiasis in individuals with CT genotype compared to CC genotype). Moreover, there was also a higher frequency of CT/TT genotypes among patients with nephrolithiasis (adjusted OR = 1.49, 95% CI = 1.02-2.19: the risk of developing nephrolithiasis in individuals with CT/TT genotypes compared to CC genotype). The risk remained for the subgroups of patients aged >53, smokers with pack-years of smoking >20, non-drinkers, non-diabetic patients, patients with hypertension, recurrent episodes and calcium oxalate stones (OR = 2.26, 95% CI = 1.31-3.91; OR = 5.47, 95% CI = 1.10-27.30; OR = 1.76, 95% CI = 1.14-2.72; OR = 1.54, 95% CI = 1.03-2.30; OR = 1.97, 95% CI = 1.01-3.82; OR = 1.67, 95% CI = 1.06-2.62; OR = 1.54, 95% CI = 1.02-2.32, respectively). Biochemical parameters did not differ between genotypes. Compared to controls (18.57 ± 5.80 ng/mL), nephrolithiasis patients had significantly higher serum MMP-9 levels (30.17 ± 6.78 ng/mL, p < 0.001). The serum MMP-9 levels of patients with CT/TT genotypes of MMP-9-1562C>T were significantly higher than those with CC genotype (32.00 ± 6.33 vs. 29.13 ± 6.85 ng/mL, p = 0.037).

Conclusion

The MMP-9-1562C>T polymorphism in association with its soluble protein increased the risk of kidney stone, thus suggesting it could be used as a susceptibility biomarker for nephrolithiasis. Further functional studies and larger studies that include environmental exposure data are needed to confirm the findings.

Metabolic Syndrome and Nephrolithiasis; A Cross Sectional Population-based Study on the Baseline Data of the PERSIAN Kavar Cohort Study

OBJECTIVE

To explore the relationship between metabolic syndrome and its components with nephrolithiasis.

METHODS

In current study, 4,901 individuals from the PERSIAN (Prospective Epidemiological Research Studies in IrAN) Kavar cohort study were included. Metabolic syndrome was defined according to the ATP III criteria (2005 revision). The nephrolithiasis was assessed using a structured questionnaire, and ultrasound findings were reviewed in subjects who reported positive history of nephrolithiasis. We applied logistic regression to estimate the odds ratio (OR) and 95% confidence interval (CI).

RESULTS

The prevalence of nephrolithiasis and metabolic syndrome was 28.5% and 40.91%, respectively. Almost 31% of the patients with metabolic syndrome had a history of nephrolithiasis. Multivariable logistic regression analysis revealed a positive association between metabolic syndrome and nephrolithiasis (OR= 1.30, 95% CI: 1.14-1.49, P<.001) after adjustment age, sex, ethnicity, physical activity, smoking status, and alcohol intake. Furthermore, the relation was higher for elders aged 50 years or more (P for interaction= .016) and Turk Nomad participants (P for interaction= 0.044) than the others. There was also a positive independent association between hypertension (OR=1.29, 95% CI: 1.12-1.48, P<.001) and hypertriglyceridemia (OR= 1.15, 95% CI: 1.01-1.31, P=.033) with nephrolithiasis.

CONCLUSION

In this large sample study, we demonstrate a weak positive association between metabolic syndrome, hypertension, and hypertriglyceridemia with nephrolithiasis.

Epidemiology of Kidney Stones

In the past two decades, major breakthroughs that improve our understanding of the pathophysiology and therapy of kidney stones (KS) have been lacking. The disease continues to be challenging for patients, physicians, and healthcare systems alike. In this context, epidemiological studies are striving to elucidate the worldwide changes in the patterns and the burden of the disease and identify modifiable risk factors that contribute to the development of kidney stones. Our expanding knowledge of the epidemiology of kidney stones is of paramount importance and largely upgrades the modern management of the disease. In this paper, we review the variables affecting prevalence and incidence, including age, gender, race, ethnicity, occupation, climate, geography, systemic diseases, diabetes, vascular disease, chronic kidney disease, and dietary risk factors relevant to kidney stones.

Prevalence and risk factors of kidney stone disease in population aged 40-70 years old in Kharameh cohort study: a cross-sectional population-based study in southern Iran

BACKGROUND

Kidney stone is the major cause of morbidity, and its prevalence is increasing in the world. This study aimed to assess the prevalence and risk factors of kidney stone in the adult population of southern Iran based on the data of the Kharameh Cohort Study.

METHODS

This cross-sectional study was conducted on 10,663 individuals aged 40-70 years old, using the baseline data of Kharamah cohort study, which started in 2014. Among all participants, 2251 individuals had a history of kidney stone. The participants' demographic characteristics, behavioral habits, and the history of underlying diseases were investigated. The crude and Age Standardized Prevalence Rate of kidney stones was calculated. Also, logistic regression was used to identify the predictors of kidney stone. To check the goodness of fit index of the model, we used the Hosmer-Lemeshow test. All analyses were performed in STATA software.

RESULTS

The prevalence of kidney stone was estimated 21.11%. Also, the Age Standardized Prevalence Rate in men and women was calculated 24.3% and 18.7%, respectively. The mean age of the participants was 52.15 years. Higher prevalence of kidney stone was seen in women aged 40-50 years (40.47%, p = 0.0001) and moderate level of social economic status (31.47%, p = 0.03), men with overweight (44.69%, p < 0.0001) and those in a very high level of social economic status (35.75%, p = 0.001). The results of multiple logistic regression showed that the chance of having kidney stone was 1.17 times higher in diabetic individuals, 1.43 times higher in hypertensive individuals, 2.21 times higher in individuals with fatty liver, and 1.35 times higher in individuals with overweight. The level of socio economic status, male sex, and age were the other factors related to kidney stone.

CONCLUSION

In this study, underlying diseases such as fatty liver, diabetes, and hypertension as well as age, male sex, overweight, and high social economic status were identified as important risk factors for kidney stone. Therefore, identifying individuals at risk of kidney stone and providing the necessary training can greatly help to reduce this disease. However, health policymakers should prepare preventive strategies to reduce the occurrence of kidney stone.

Nephrolithiasis: A Red Flag for Cardiovascular Risk

Epidemiological evidence shows that nephrolithiasis is associated with cardiovascular (CV) morbidities. The association between nephrolithiasis and CV disease is not surprising because both diseases share conditions that facilitate their development. Metabolic conditions, encompassed in the definition of metabolic syndrome (MS), and habits that promote nephrolithiasis by altering urine composition also promote clinical manifestations of CV disease. By inducing oxidative stress, these conditions cause endothelial dysfunction and increased arterial stiffness, which are both well-known predictors of CV disease. Furthermore, the subtle systemic metabolic acidosis observed in stone formers with CV disease may have a pathogenic role by increasing bone turnover and leading to reduced mineral content and osteoporosis/osteopenia. Heart valves and/or coronary artery and aortic calcifications are frequently associated with reduced mineral density. This is known as the 'calcification paradox' in osteoporosis and has also been observed in subjects with calcium nephrolithiasis. Evidence supports the hypothesis that osteoporosis/osteopenia is an independent risk factor for the development of CV calcifications. In the long term, episodes of renal stones may occur from the onset of metabolic derangements/MS to arterial stiffness/atherosclerosis and CV morbidities. These episodes should be considered a warning sign of an ongoing and silent atherosclerotic process. The evaluation of cardiometabolic risk factors and MS components should be routine in the assessment of renal stone formers. This would allow for treatment and prevention of the development of CV complications, which are much more severe for the patient and for public health.

Physical Activity Reduces the Effect of High Body Mass Index on Kidney Stones in Diabetes Participants From the 2007–2018 NHANES Cycles: A Cross-Sectional Study

Background

Body mass index (BMI) is a vital risk factor for kidney stones, but physical activity may reduce the incidence of kidney stones. However, it remains unknown whether physical activity reduces the effect of high BMI on kidney stones in diabetes participants.

Methods

We included clinical information from 4,008 adult participants with diabetes from the National Health and Nutrition Examination Survey (NHANES) database from 2007 to 2018. Univariate and multivariate logistic regression analyses were used to analyze the relationship between BMI and kidney stones, as well as the risk of BMI and kidney stones in different physical activity subgroups.

Results

A total of 4,008 diabetic participants were included in this study, of whom 652 (16.3%) self-reported a history of kidney stones. Logistic regression analysis showed a positive association between BMI and kidney stones. After adjusting for other confounders, the adjusted ORs for the risk of kidney stones was 1.514 (95% CI, 1.134–2.022, p = 0.005) for participants with BMI ≥30 kg/m² among all participants; the risk of kidney stones was elevated (OR = 1.572, 95% CI, 1.134–2.022, p = 0.005) in group without physical activity, and a reduced risk (OR = 1.421, 95% CI, 0.847–2.382, p = 0.183) in the group with physical activity. Furthermore, similar results were found in most subgroups.

Conclusion

Our study suggests that high BMI is a risk factor for diabetes kidney stone participants and that physical activity may moderate this relationship to some extent.

Association Between Preoperative Blood Glucose Level and Hospital Length of Stay in Patients With Kidney Stones Undergoing Percutaneous Nephrolithotomy

Aim

To assess the effect of preoperative blood glucose (POBG) levels on the length of stay (LOS) in patients with kidney stones undergoing percutaneous nephrolithotomy (PCNL).

Methods

We conducted a retrospective study of patients who underwent PCNL at the Zhongda Hospital of Southeast University from 2013 to 2019. The relationship between POBG level and LOS was investigated by dose-response analysis curves of restricted cubic spline function.

Results

We included 310 patients and divided them into three groups (&lt;5.04, 5.04 to &lt;6.88, ≥6.88 mmol/L) according to the POBG levels. Patients with POBG levels ≥6.88 mmol/L (adjusted odds risk [aOR] 1.67; 95% CI 0.83–3.33) had a 67% higher risk of LOS &gt; 2 weeks than patients with POBG levels &lt;5.04 mmol/L. A positive dose-response analysis curve was observed between POBG and the adjusted risk of LOS &gt;2 weeks. Similar results were observed in the subgroups analysis.

Conclusion

We demonstrated that higher POBG levels were significantly associated with longer LOS in patients with kidney stones undergoing PCNL.

Global Trends in Incidence and Burden of Urolithiasis from 1990 to 2019: An Analysis of Global Burden of Disease Study Data

Background

Urolithiasis is among the most common urologic diagnoses globally, with substantial burden and cost on healthcare systems worldwide. Increasing evidence links urolithiasis with an array of risk factors, including diet and lifestyle trends, noncommunicable diseases such as diabetes and obesity, and global warming.

Objective

To examine geographic, temporal, and sociodemographic patterns to better understand global disease burden of urolithiasis.

Design, setting, and participants

We extracted data on age-standardized incidence rate (ASIR), deaths, and disability-adjusted life years (DALYs) attributed to urolithiasis for 21 regions, including 204 countries, for 1990–2019 from the Global Burden of Disease (GBD) study.

Outcome measurements and statistical analysis

Data were analyzed at the global, regional, and country levels, as well as stratified by the Socio-Demographic Index. The average annual percentage change (AAPC) was calculated to measure temporal trends across groups.

Results and limitations

Globally, total cases, DALYs, and deaths attributed to urolithiasis increased over the study period, while the age-standardized rates of these measures decreased. The age-standardized incidence of urolithiasis decreased from 1696.2 (95% confidence interval [CI] 1358.1–2078.1) cases per 100 000 population in 1990 to 1394.0 (95% CI, 1126.4–1688.2) cases per 100 000 population in 2019, with an AAPC of −0.7 (95% CI [−0.8, −0.6]). Of the GBD regions, Eastern Europe demonstrated a consistently higher ASIR of urolithiasis than all other regions, while the Caribbean had the highest AAPC. This study is limited by the available national and regional data, as described in the original GBD study.

Conclusions

Worldwide, total cases, DALYs, and deaths attributed to urolithiasis have increased since 1990, while age-standardized rates have decreased, with demonstrated regional and sociodemographic variation. Multifaceted strategies to address urolithiasis prevention and treatment are necessary.

Patient summary

In this study, we looked at trends in the global burden of stone disease using data from 204 countries from 1990 to 2019. We found that the overall burden has increased, but it varies by age, sociodemographic variables, and geographic region. We conclude that we need adaptable policies that suit the specific needs of the country to address this burden.

Risk factors of kidney stone disease: a cross-sectional study in the southeast of Iran

BACKGROUND

The prevalence of kidney stones in the world is increasing and environmental factors seem to play a major role in this issue. The aim of the present study was to investigate the prevalence of risk factors of kidney stones in the adult population of Rafsanjan city based on the data of the Rafsanjan Cohort Study (RCS).

METHODS

In the baseline phase of this study, 10,000 people aged 35 to 70 years are enrolled in the RCS, as one of the prospective epidemiological research studies in Iran. From this population, 9932 participants completed related demographic questionnaires as well as reported a history of diabetes mellitus, kidney stone, and hypertension diseases. The obtained data were analyzed using univariable and multivariable logistics regression.

RESULTS

According to the obtained results, 46.54% of the studied population were male and 53.46% were female. The mean age of the participants was 49.94 ± 9.56 years. 2392 people accounting for 24.08% of the population had kidney stones. After adjustment of the variables, six variables of gender, WSI, no consumption of purified water, BMI, and history of hypertension and diabetes were found to be significant related factors of kidney stone disease.

CONCLUSIONS

Gender, hypertension, obesity, diabetes, and personal habits like alcohol consumption, opium use and, cigarette smoking are effective in the development of kidney stones. So, by identifying the susceptible patients and teaching them, the burden of the disease on society and the individual can be reduced. The results of this study are helpful to health care providers for preventive planning for kidney stone disease.

Risk of Metabolic Syndrome in Kidney Stone Formers: A Comparative Cohort Study with a Median Follow-Up of 19 Years

Background: Kidney stone formers (SF) are more likely to develop diabetes mellitus (DM), but there is no study examining risk of metabolic syndrome (MetS) in this population. We aimed to describe the risk of MetS in SF compared to non-SF. Methods and Materials: SF referred to a tertiary referral metabolic centre in Southern England from 1990 to 2007, comparator patients were age, sex, and period (first stone) matched with 3:1 ratio from the same primary care database. SF with no documentation or previous MetS were excluded. Ethical approval was obtained and MetS was defined using the modified Association of American Clinical Endocrinologists (AACE) criteria. Analysis with cox proportional hazard regression. Results: In total, 828 SF were included after 1000 records were screened for inclusion, with 2484 age and sex matched non-SF comparators. Median follow-up was 19 years (interquartile range—IQR: 15–22) for both stone formers and stone-free comparators. SF were at significantly increased risk of developing MetS (hazard ratio—HR: 1.77; 95% confidence interval—CI: 1.55–2.03, p < 0.001). This effect was robust to adjustment for pre-existing components (HR: 1.91; 95% CI: 1.66–2.19, p < 0.001). Conclusions: Kidney stone formers are at increased risk of developing metabolic syndrome. Given the pathophysiological mechanism, the stone is likely a ‘symptom’ of an underlying metabolic abnormality, whether covert or overt. This has implications the risk of further stone events and cardiovascular disease.

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.

Solute Carrier Transporters as Potential Targets for the Treatment of Metabolic Disease

The solute carrier (SLC) superfamily comprises more than 400 transport proteins mediating the influx and efflux of substances such as ions, nucleotides, and sugars across biological membranes. Over 80 SLC transporters have been linked to human diseases, including obesity and type 2 diabetes (T2D). This observation highlights the importance of SLCs for human (patho)physiology. Yet, only a small number of SLC proteins are validated drug targets. The most recent drug class approved for the treatment of T2D targets sodium-glucose cotransporter 2, product of the SLC5A2 gene. There is great interest in identifying other SLC transporters as potential targets for the treatment of metabolic diseases. Finding better treatments will prove essential in future years, given the enormous personal and socioeconomic burden posed by more than 500 million patients with T2D by 2040 worldwide. In this review, we summarize the evidence for SLC transporters as target structures in metabolic disease. To this end, we identified SLC13A5/sodium-coupled citrate transporter, and recent proof-of-concept studies confirm its therapeutic potential in T2D and nonalcoholic fatty liver disease. Further SLC transporters were linked in multiple genome-wide association studies to T2D or related metabolic disorders. In addition to presenting better-characterized potential therapeutic targets, we discuss the likely unnoticed link between other SLC transporters and metabolic disease. Recognition of their potential may promote research on these proteins for future medical management of human metabolic diseases such as obesity, fatty liver disease, and T2D. SIGNIFICANCE STATEMENT: Given the fact that the prevalence of human metabolic diseases such as obesity and type 2 diabetes has dramatically risen, pharmacological intervention will be a key future approach to managing their burden and reducing mortality. In this review, we present the evidence for solute carrier (SLC) genes associated with human metabolic diseases and discuss the potential of SLC transporters as therapeutic target structures.

Urinary oxalate as a potential mediator of kidney disease in diabetes mellitus and obesity

PURPOSE OF REVIEW

Hyperoxaluria can cause kidney disease through multiple mechanisms, including tubular obstruction from calcium oxalate crystals, sterile inflammation, and tubular epithelial cell injury. Hyperoxaluria is also observed in individuals with diabetes mellitus and obesity, which are in turn risk factors for chronic kidney disease (CKD). Whether hyperoxaluria is a potential mediator of increased risk of CKD in diabetes mellitus and obesity is unknown.

RECENT FINDINGS

Individuals with diabetes have increased levels of plasma glyoxal (a protein glycation product) and glyoxylate, both of which are precursors for oxalate. Increased gut absorption of oxalate in obesity may be because of obesity-associated inflammation. A recent study in individuals with CKD found that higher 24 h urinary oxalate excretion was independently associated with increased risk of kidney disease progression, especially in individuals with diabetes and obesity.

SUMMARY

Both diabetes mellitus and obesity are associated with higher urinary oxalate excretion through distinct mechanisms. Hyperoxaluria could be a mechanism by which kidney disease develops in individuals with diabetes mellitus or obesity and could also contribute to progressive loss of renal function. Future research on pharmacologic or dietary measures to limit oxalate absorption or generation are required to test whether lowering urinary oxalate excretion is beneficial in preventing kidney disease development and progression in diabetes mellitus and obesity.

Obesity and stones

PURPOSE OF REVIEW

The incidence of urolithiasis has shown a prominent increase in the last two to three decades and evidence-based data have clearly indicated the certain role of obesity and overweight in both children and adults. As a certain component of metabolic syndrome, 'obesity' has been found to have a significant impact on the urinary metabolic risk factors which may be important in stone formation. In this present review article, we aimed to evaluate the possible association between obesity and urolithiasis and related risk factors. The epidemiology, pathophysiology, and management of stone disease in obese cases will be discussed in detail.

RECENT FINDINGS

The possible influence of overweight/obesity on the metabolic stone-forming risk factors has been subjected to several studies which in turn well demonstrated the increased risk of stone formation in this population. Although the exact underlying mechanisms are still to be outlined, some certain pathogenetic factors, namely, changes in urinary pH and increased excretion of some urinary stone components have been well demonstrated. Given this increased risk status, these cases require a more comprehensive workup for urolithiasis. Appropriate metabolic evaluation-based medical therapy alongside dietary recommendations will be effective in preventing stone formation.

SUMMARY

Patients suffering from obesity problem have particular risk factors for urolithiasis when compared with their normal-weight counterparts. All efforts should be taken to increase the awareness of this problem and necessary precautions with well-planned treatment plan are the main tasks for urologists.

Evaluation of the economic burden of kidney stone disease in the UK: a retrospective cohort study with a mean follow-up of 19 years

OBJECTIVE

To estimate the cost of kidney stone disease (KSD) in England.

PATIENTS AND METHODS

We conducted a retrospective cohort study of patients with KSD, referred to a metabolic stone clinic between 1990 and 2007 using electronic records of patients with KSD in a tertiary referral centre, to determine cost using UK National Health Service (NHS) tariff, with subsequent extrapolation to the entire England population. Those with no documentation and <5 years follow-up were excluded. The outcome measure was calculation of cost (as per 2018 NHS tariff) presented as lower and higher estimates for: per episode; total within the cohort; and estimation of initial, 5-,10- and 15-year costs for the cohort and total population in England. Linear regression was used to examine for significant predictors of per episode and total cost.

RESULTS

A total of 781 patients were included in the study after 1000 records were screened for inclusion, with a mean follow-up of 19 years. The mean (SD) overall costs per episode were between £1277 (1724) and £2887 (2492). Total initial costs for the cohort were between £950 842 and £2 336 442, rising to between £1.43 million and £3.02 million at 15 years of follow-up. Estimated cost in 2010 in England alone was between £190 million and £324 million.

CONCLUSION

KSD is a costly disease, comparable to the combined cost of prostate and bladder cancer in UK.

Does chronic hyperglycaemia increase the risk of kidney stone disease? results from a systematic review and meta-analysis

DESIGN

Systematic review and meta-analysis of observational studies was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for studies reporting on diabetes mellitus (DM) or metabolic syndrome (MetS) and kidney stone disease (KSD).

OBJECTIVE

To examine the association between chronic hyperglycaemia, in the form of DM and impaired glucose tolerance (IGT) in the context of MetS and KSD.

SETTING

Population-based observational studies. Databases searched: Ovid MEDLINE without revisions (1996 to June 2018), Cochrane Library (2018), CINAHL (1990 to June 2018), ClinicalTrials.gov, Google Scholar and individual journals including the Journal of Urology, European Urology and Kidney International.

PARTICIPANTS

Patients with and without chronic hyperglycaemic states (DM and MetS).

MAIN OUTCOME MEASURES

English language articles from January 2001 to June 2018 reporting on observational studies.

EXCLUSIONS

No comparator group or fewer than 100 patients. Unadjusted values were used for meta-analysis, with further meta-regression presented as adjusted values. Bias was assessed using Newcastle-Ottawa scale.

RESULTS

2340 articles were screened with 13 studies included for meta-analysis, 7 DM (three cohort) and 6 MetS. Five of the MetS studies provided data on IGT alone. These included: DM, n=28 329; MetS, n=31 767; IGT, n=12 770.

CONTROLS

DM, n=5 89 791; MetS, n=1 78 050; IGT, n=2 93 852 patients. Adjusted risk for DM cohort studies, RR=1.23 (0.94 to 1.51) (p<0.001). Adjusted ORs for: DM cross-sectional/case-control studies, OR=1.32 (1.21 to 1.43) (p<0.001); IGT, OR=1.26 (0.92 to 1.58) (p<0.0001) and MetS, OR=1.35 (1.16 to 1.54) (p<0.0001). There was no significant difference between IGT and DM (cross-sectional/case-control), nor IGT and MetS. There was a moderate risk of publication bias. Statistical heterogeneity remained significant in adjusted DM cohort values and adjusted IGT (cross-sectional/case-control), but non-signficant for adjusted DM (cross-sectional/case-control).

CONCLUSION

Chronic hyperglycaemia increases the risk of developing kidney stone disease. In the context of the diabetes pandemic, this will increase the burden of stone related morbidity and mortality.

PROSPERO REGISTRATION NUMBER

CRD42018093382.

Risk of Nephrolithiasis in Patients With Sleep Apnea: A Population-Based Cohort Study

STUDY OBJECTIVES

To delineate the relationship between sleep apnea and subsequent risk of nephrolithiasis.

METHODS

We conducted a retrospective cohort analysis of a general population sample from Taiwan National Health Insurance Research Database (NHIRD) from January 1, 2000 to December 31, 2012. Patients with sleep apnea without prior diagnosis of nephrolithiasis (n = 7,831) were identified and subsequent development of nephrolithiasis was compared to an age- and sex-matched control group (n = 31,293) without sleep apnea. The Cox proportional hazard regression models were used to evaluate the association between sleep apnea and subsequent nephrolithiasis development.

RESULTS

After adjusting for age, sex, and comorbidities, the risk of nephrolithiasis remained significantly increased in the sleep apnea group (hazard ratio [HR] = 1.35; 95% confidence interval [CI] = 1.23-1.48; P < .001). Compared to controls, elevated HRs of nephrolithiasis were observed for male patients (HR = 1.22; 95% CI 1.09-1.36; P < .001) and those aged 20-39 years (HR = 1.28; 95% CI 1.09-1.49; P < .01) and 40-59 years (HR = 1.17, 95% CI 1.03-1.34, P < .05) in the sleep apnea cohort. Risk of nephrolithiasis in patients with sleep apnea increased significantly with concomitant metabolic-related comorbidities, gouty arthritis, and urinary tract infection.

CONCLUSIONS

Sleep apnea is associated with an increased subsequent risk of the development of nephrolithiasis. Young male patients with sleep apnea and concomitant comorbidities are at the greatest risk for nephrolithiasis formation.

Integrative Personal Omics Profiles during Periods of Weight Gain and Loss

Advances in omics technologies now allow an unprecedented level of phenotyping for human diseases, including obesity, in which individual responses to excess weight are heterogeneous and unpredictable. To aid the development of better understanding of these phenotypes, we performed a controlled longitudinal weight perturbation study combining multiple omics strategies (genomics, transcriptomics, multiple proteomics assays, metabolomics, and microbiomics) during periods of weight gain and loss in humans. Results demonstrated that: (1) weight gain is associated with the activation of strong inflammatory and hypertrophic cardiomyopathy signatures in blood; (2) although weight loss reverses some changes, a number of signatures persist, indicative of long-term physiologic changes; (3) we observed omics signatures associated with insulin resistance that may serve as novel diagnostics; (4) specific biomolecules were highly individualized and stable in response to perturbations, potentially representing stable personalized markers. Most data are available open access and serve as a valuable resource for the community.

Increased risk of endotracheal intubation and heart failure following acute myocardial infarction in patients with urolithiasis: a nationwide population-based study

BACKGROUND

Urolithiasis is a common urinary tract disease worldwide. It has been connected to systemic diseases, including hypertension, diabetes mellitus, metabolic syndrome, and cardiovascular disease. In the current study, we aimed to evaluate the relationship between urolithiasis and the complications of acute myocardial infarction (AMI).

MATERIALS AND METHODS

Data were obtained from the Longitudinal Health Insurance Database 2005 of the National Health Insurance Research Database. All AMI cases, both those who were hospitalized and those who were treated in the emergency department, were identified using the International Classification of Diseases, ninth revision, Clinical Modification (ICD-9-CM) code.

RESULTS

A total of 37,052 patients with urinary calculi and 148,209 control subjects were enrolled in this study. The average follow-up period was 9.51 years. The risk of AMI was higher among patients with urolithiasis (adjusted hazard ratio [aHR] 1.07, 95% confidence interval [95% CI] 1.03-1.13). We detected a significant association between urolithiasis and intubation (aHR 1.53, 95% CI 1.36-1.73), intensive care unit treatment (aHR 1.22, 95% CI 1.13-1.32), heart failure (aHR 1.59, 95% CI 1.42-1.78), shock (aHR 1.53, 95% CI 1.32-1.77), and arrhythmias (aHR 1.18, 95% CI 1.06-1.33). Furthermore, certain medical treatments for urolithiasis were found to be related to myocardial infarction (MI). Nonsteroidal anti-inflammatory drugs (NSAIDs) were significantly associated with a high risk of AMI. In contrast, allopurinol, thiazide diuretic, potassium-sparing diuretics, and α-blockers have negative association with AMI.

CONCLUSION

Urolithiasis had a significantly increased risk of endotracheal intubation and heart failure following AMI. In addition, urolithiasis was also associated with a high risk of intensive care unit treatment, shock, and arrhythmias after AMI. Medical treatments for urolithiasis may decrease the risk of MI, except the use of NSAIDs.

The association of nephrolithiasis with metabolic syndrome and its components: a cross-sectional analysis

Background

Metabolic syndrome is a worldwide disorder and also the major risk factor of several systemic diseases. Evidence identifying the association between metabolic syndrome and nephrolithiasis is lacking, especially in Taiwan.

Aim

The aim of this study was to investigate the association between nephrolithiasis and metabolic syndrome and its components.

Design and setting

This was a cross-sectional study conducted in the Health Examination Department of a medical center in Changhua, Taiwan, from January 2010 to December 2010.

Methods

We reviewed the medical records of patients who had visited the Health Examination Center of Changhua Christian Hospital in 2010. A total of 3,886 individuals were enrolled. According to the exclusion criteria, those with an age <20 years and an abnormal renal function were excluded. A total of 3,793 subjects were included. All P-values are two tailed, and P<0.05 was defined as statistically significant.

Results

The results showed a correlation between nephrolithiasis and metabolic syndrome and its components. The multivariate-adjusted odds ratio (OR) (95% confidence interval [CI]) of metabolic syndrome for nephrolithiasis was 1.318 (1.083–1.604), with a P-value of 0.006. Larger waist circumference (multivariable-adjusted OR 1.338; 95% CI 1.098–1.631; P=0.004), higher blood pressure (multivariable-adjusted OR 1.333; 95% CI 1.106–1.607; P=0.003), and increased fasting glucose (multivariable-adjusted OR 1.276; 95% CI 1.054–1.546; P=0.01) were associated with nephrolithiasis.

Conclusion

This is the first study in Taiwan to investigate the relationship between metabolic syndrome and nephrolithiasis. The mechanism is controversial, and several hypotheses are offered. Adequate lifestyle modification and proper treatment in metabolic syndrome management may both contribute to nephrolithiasis prevention.

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.

Metabolic syndrome and nephrolithiasis

Problem

This review focuses on the association between the metabolic syndrome (MS) and nephrolithiasis.

Findings

Associations between nephrolithiasis and systemic diseases are recognized, including atherosclerosis, cardiovascular (CV) disease, hypertension (HNT), diabetes mellitus (DM)—composite risk factors grouped as the MS. Kidney stones incidence is increasing in this particularly high risk group. Those with stones are prone to the disease and those with the systemic disease are at risk for stone formation, with the highest incidence in persons with multiple traits of the MS. Pathophysiologic explanations for the increased stone risk related to MS are likely complex and dynamic.

Conclusions

Kidney stones disproportionately affect persons with some or all traits of MS. One unifying theory may be of a common systemic malfunction of inflammation and tissue damage as an underlying mechanism, but it is unlikely to be the only mechanistic explanation. Further research is needed to investigate this and other hypotheses that go beyond population based and urine physiochemical studies in order to elucidate the mechanisms behind the individual disease states themselves.

Systemic implications of urinary stone disease

Urinary stone disease is the third most common condition affecting the urinary tract. It contributes to a great deal of morbidity for both men and women, and cost the United States (US) over 5.3 billion dollars in 2000 alone. Moreover, it is associated with systemic diseases such as hypertension, diabetes, and other components of the metabolic syndrome. Reciprocally, these systemic diseases may be contributing to the rising incidence in urinary stone disease. Previously described mechanisms of stone formation attribute stone development and growth to the urinary milieu. While this may partly influence the process, it cannot account for the associations between systemic diseases and stones observed in large community-based studies. Here we present a review of the evidence demonstrating a link between urinary stone disease and components of the metabolic syndrome. We believe a vascular etiology for the initiation of urinary stones may tie these processes together.

Effect of urinary stone disease and its treatment on renal function

Urolithiasis is a common disease that affects urinary tract in all age groups. Both in adults and in children, stone size, location, renal anatomy, and other factors, can influence the success of treatment modalities. Recently, there has been a great advancement in technology for minimally invasive management of urinary stones. The epoch of open treatment modalities has passed and currently there are much less invasive treatment approaches, such as percutaneous nephrolithotomy, ureteroscopy, shockwave lithotripsy, and retrograde internal Surgery. Furthermore, advancement in imaging technics ensures substantial knowledge that permit physician to decide the most convenient treatment method for the patient. Thus, effective and rapid treatment of urinary tract stones is substantial for the preservation of the renal function. In this review, the effects of the treatment options for urinary stones on renal function have been reviewed.

Does diabetes affect the distribution and number of interstitial cells and neuronal tissue in the ureter, bladder, prostate, and urethra of humans?

INTRODUCTION

The aim of this study was to investigate and compare the distribution and number of interstitial cells (ICs) and neuronal tissue in the ureter, bladder, prostate, and urethra of human patients with and without diabetes.

MATERIAL AND METHODS

Human tissue was obtained from patients who had undergone radical cystectomy for bladder cancer (10 diabetic and 11 non-diabetic males). Interstitial cells were stained immunohistochemically with anti-human CD117 (c-kit) rabbit polyclonal antibody, Vimentin, and Connexin-43. Neural tissue was stained with synaptophysin. The number of ICs and neurons was evaluated and compared between the groups (diabetic versus non-diabetic).

RESULTS

The mean number of c-kit (+) ICs in bladder lamina propria was significantly decreased in diabetics (32.40 ±12.96 versus 57.18 ±25.37, p = 0.036). The mean number of ICs in the detrusor muscle was significantly decreased in diabetics (40.50 ±16.79 versus 64.55 ±22.08, p = 0.013). Between the groups, no significant differences were detected regarding the number of ICs at the level of the ureter, urethra, and prostate. No significant differences were detected regarding the number of nerves in the ureter, bladder, prostate, and urethra of both groups.

CONCLUSIONS

The number of ICs may be decreased in the lamina propria and detrusor muscle of the human bladder in diabetes. This can be an underlying cause of lower urinary tract (LUT) dysfunction in diabetics. Research into the development of drugs targeting or stimulating IC function in order to prevent diabetic LUT dysfunction is warranted.

Increased risk of acute coronary syndrome among patients with urinary stone disease: a nationwide population-based cohort study

Background/Objectives

Urinary stones (US) are associated with systemic metabolic and endocrine disorders that share risk factors typically associated with acute coronary syndrome (ACS).

Methods

For this investigation, 30 142 patients with US were set as the research group, and 121 768 randomly selected patients were set as the comparison group through frequency matching by age, sex, and index year. Each patient was individually tracked to identify those who developed ACS during the follow-up period. Cox proportional hazards regression and the Kaplan-Meier method were adopted to calculate the hazard ratios of ACS risk and plot the survival curve.

Results

Overall, 275 (13.4 per 10 000 person-y) and 736 events (9.1 per 10 000 person-y) were observed among patients in the research and comparison cohorts, respectively. The patients with US had a substantially lower ACS-free survival rate compared with that of the patients in the comparison cohort (P<.001). After adjusting for potential risk factors, the patients with US were observed to have a 1.22-fold higher risk of ACS compared with patients in the comparison cohort (95% confidence interval = 1.05–1.40, P<.001), particularly among younger patients.

Conclusions

The results indicate that US is associated with increased risk of developing ACS, particularly among young (≤49 years) and male adults. Future studies should examine the possible mechanisms of US-related ACS morbidity by conducting multicenter recruitment and measurements of laboratory data.

Analysis of altered microRNA expression profiles in proximal renal tubular cells in response to calcium oxalate monohydrate crystal adhesion: implications for kidney stone disease

BACKGROUND

Calcium oxalate monohydrate (COM) is the major crystalline component in kidney stones and its adhesion to renal tubular cells leads to tubular injury. However, COM-induced toxic effects in renal tubular cells remain ambiguous. MicroRNAs (miRNAs) play an important role in gene regulation at the posttranscriptional levels.

OBJECTIVE

The present study aimed to assess the potential changes in microRNAs of proximal renal tubular cells in response to the adhesion of calcium oxalate monohydrate (COM) crystals.

METHODOLOGY

Lactate dehydrogenase (LDH) activity and DAPI staining were used to measure the toxic effects of HK-2 cells exposed to COM crystals. MicroRNA microarray and mRNA microarray were applied to evaluate the expression of HK-2 cells exposed to COM crystals. Quantitative real-time PCR (qRT-PCR) technology was used to validate the microarray results. Target prediction, Gene Ontology (GO) analysis and pathway analysis were applied to predict the potential roles of microRNAs in biological processes.

PRINCIPAL FINDINGS

Our study showed that COM crystals significantly altered the global expression profile of miRNAs in vitro. After 24 h treatment with a dose (1 mmol/L), 25 miRNAs were differentially expressed with a more than 1.5-fold change, of these miRNAs, 16 were up-regulated and 9 were down-regulated. A majority of these differentially expressed miRNAs were associated with cell death, mitochondrion and metabolic process. Target prediction and GO analysis suggested that these differentially expressed miRNAs potentially targeted many genes which were related to apoptosis, regulation of metabolic process, intracellular signaling cascade, insulin signaling pathway and type 2 diabetes.

CONCLUSION

Our study provides new insights into the role of miRNAs in the pathogenesis associated with nephrolithiasis.

Percutaneous nephrolithotomy increases the risk of diabetes: a 5-year follow-up study

OBJECTIVE

To examine the risk of diabetes mellitus within a 5-year period among patients with nephrolithiasis undergoing percutaneous nephrolithotomy .

METHODS

A total of 304 patients who underwent percutaneous nephrolithotomy were included in the study cohort. A total of 3040 patients with nephrolithiasis who did not undergo percutaneous nephrolithotomy were used as a comparison cohort. All participants included in the present study were individually tracked for a 5-year period in order to identify those who developed diabetes mellitus during this timeframe.

RESULTS

The incidence rate of diabetes mellitus was 3.03 per 100 person-years in participants who underwent percutaneous nephrolithotomy and 1.65 per 100 person-years in participants who did not undergo percutaneous nephrolithotomy. After adjusting for the participants' monthly income, geographic location, urbanization level, hypertension, hyperlipidemia and alcohol abuse/alcohol dependence syndrome, the hazard ratio of receiving a first diagnosis of diabetes mellitus during the 5-year follow-up period was 1.96 (95% confidence interval 1.40-2.77) for participants who underwent percutaneous nephrolithotomy. Furthermore, compared with extracorporeal shock wave lithotripsy or endoscopic intervention, participants who underwent percutaneous nephrolithotomy had a significantly increased hazard of developing diabetes mellitus (adjusted hazard ratio 1.79 for a percutaneous nephrolithotomy vs extracorporeal shockwave lithotripsy, and adjusted hazard ratio 1.71 for a percutaneous nephrolithotomy vs an endoscopic intervention).

CONCLUSIONS

The present results suggest an association between patients with nephrolithiasis who undergo a percutaneous nephrolithotomy and a subsequent diabetes mellitus diagnosis.

History of kidney stones and the risk of coronary heart disease

IMPORTANCE

Kidney stone disease is common and may be associated with an increased risk of coronary heart disease (CHD). Previous studies of the association between kidney stones and CHD have often not controlled for important risk factors, and the results have been inconsistent.

OBJECTIVE

To examine the association between a history of kidney stones and the risk of CHD in 3 large prospective cohorts.

DESIGN, SETTING, AND PARTICIPANTS

A prospective study of 45,748 men and 196,357 women in the United States without a history of CHD at baseline who were participants in the Health Professionals Follow-up Study (HPFS) (45,748 men aged 40-75 years; follow-up from 1986 to 2010), Nurses' Health Study I (NHS I) (90,235 women aged 30-55 years; follow-up from 1992 to 2010), and Nurses' Health Study II (NHS II) (106,122 women aged 25-42 years; follow-up from 1991 to 2009). The diagnoses of kidney stones and CHD were updated biennially during follow-up.

MAIN OUTCOMES AND MEASURES

Coronary heart disease was defined as fatal or nonfatal myocardial infarction (MI) or coronary revascularization. The outcome was identified by biennial questionnaires and confirmed through review of medical records. RESULTS Of a total of 242,105 participants, 19,678 reported a history of kidney stones. After up to 24 years of follow-up in men and 18 years in women, 16,838 incident cases of CHD occurred. After adjusting for potential confounders, among women, those with a reported history of kidney stones had an increased risk of CHD than those without a history of kidney stones in NHS I (incidence rate [IR], 754 vs 514 per 100,000 person-years; multivariable hazard ratio [HR], 1.18 [95% CI, 1.08-1.28]) and NHS II (IR, 144 vs 55 per 100,000 person-years; multivariable HR, 1.48 [95% CI, 1.23-1.78]). There was no significant association in men (IR, 1355 vs 1022 per 100,000 person-years; multivariable HR, 1.06 [95% CI, 0.99-1.13]). Similar results were found when analyzing the individual end points (fatal and nonfatal MI and revascularization).

CONCLUSIONS AND RELEVANCE

Among the 2 cohorts of women, a history of kidney stones was associated with a modest but statistically significantly increased risk of CHD; there was no significant association in a separate cohort of men. Further research is needed to determine whether the association is sex-specific.

New insights into the pathogenesis of renal calculi

The pathophysiology of the various forms of urinary stone disease remains a complex topic. Epidemiologic research and the study of urine and serum chemistries have created an abundance of data to help drive the formulation of pathophysiologic theories. This article addresses the associations of urinary stone disease with hypertension, cardiovascular disease, atherosclerosis, obesity, dyslipidemia, diabetes, and other disease states. Findings regarding the impact of dietary calcium and the formation of Randall's plaques are also explored and their implications discussed. Finally, further avenues of research are explored, including genetic analyses and the use of animal models of urinary stone disease.

The association of cardiovascular disease and metabolic syndrome with nephrolithiasis

PURPOSE OF REVIEW

This review describes the relationship between nephrolithiasis, vascular disease and metabolic syndrome.

RECENT FINDINGS

There is increasing evidence that kidney stone formation is associated with a number of systemic problems including cardiovascular disease, metabolic syndrome and its components. Some of these associations are bidirectional. The reasons for these associations are not totally clear, but potential factors include metabolic responses associated with these disorders that promote a stone forming milieu in urine, environmental factors such as diet, oxidative stress and inflammation and molecular changes impacting the transport of certain analytes in urine.

SUMMARY

Urologists need to be cognizant of these associations as they may be able to contribute to an early diagnosis of a significant medical problem, or provide counseling to patients to prevent their occurrence.