The association of prevalent kidney stone disease with mortality in US adults: the National Health and Nutrition Examination Survey III, 1988-1994

Association and interactions between mixed exposure to trace elements and the prevalence of kidney stones: a study of NHANES 2017-2018

Background

The association between exposure to trace elements mixture and the prevalence of kidney stones and the interactions between elements are unclear. The aim of this study was to explore the association between exposure to trace elements mixture and the prevalence of kidney stones and the interactions between the elements.

Methods

A total of 1,244 participants (139 kidney stone formers and 1,105 non-stone former participants) in NHANES 2017-2018 were included. The exposure to trace elements was evaluated by measuring their concentration in urine samples. Three methods, Logistic regression, quantile-based g computation (qgcomp), and Bayesian kernel machine regression (BKMR), were used for analysis.

Results

According to the results from qgcomp and BKMR, a negative association was found between exposure to the 13 trace elements and the prevalence of kidney stones [OR = 0.50 (0.32, 0.78)]. Subgroup analysis revealed that Co, As, and iodine in the whole population, Co, As, and Ni in males, and Cs, iodine, and Sb in females, were most strongly associated with kidney stones. Kidney stone was found to be positively correlated with Co and negatively correlated with the other elements. Besides, there were significant interactions between Ni and Pb in the whole population, Co and iodine in males, and Pb and iodine in females.

Conclusion

There was a negative association between exposure to the mixture of 13 trace elements and the prevalence of kidney stones.

Association of serum 25-hydroxyvitamin D concentrations with all-cause mortality among individuals with kidney stone disease: the NHANES database prospective cohort study

Background

The purpose of this study was to investigate the correlation between serum 25(OH)D concentrations and all-cause mortality in patients with kidney stone disease (KSD) as the effects of a deficiency in 25-hydroxyvitamin D on KSD patients are currently unclear.

Methods

For our prospective cohort study, we included 2,916 participants from the National Health and Nutrition Examination Survey (NHANES) 2007-2018. The National Death Index (NDI) was utilized to identify all causes of death and cause-specific mortality until December 31, 2018. We calculated hazard ratios (HR) and 95% confidence intervals (CIs) using multivariate Cox regression models.

Results

During the 18,859 person-years of follow-up, a total of 375 fatalities occurred, including 83 deaths from cardiovascular disease (CVD) and 79 deaths from cancer. At baseline, individuals with higher blood 25(OH)D concentrations had lower levels of glucose, glycohemoglobin, CRP, and insulin, as well as higher levels of HDL cholesterol (P < 0.01). In the fully adjusted model (Model 3), compared to the group with the lowest 25(OH)D concentrations, those with serum 25(OH)D concentrations ≥75 nmol/L had hazard ratios (HRs) and 95% confidence intervals (CIs) of 0.48 (0.26, 0.87) for all-cause mortality (P=0.02, P for trend = 0.02). The association between serum 25(OH)D concentrations and all-cause mortality in KSD patients was found to be significantly non-linear. A 7% decrease in the risk of death from all causes was observed for each unit-nmol/L increase in serum 25(OH)D concentrations when the concentrations were below 27.7 nmol/L (P < 0.05).

Conclusion

Based on the findings, KSD patients with insufficient serum 25(OH)D concentrations were at a higher risk of all-cause mortality. Therefore, it is crucial to maintain sufficient blood 25(OH)D concentrations and prevent 25(OH)D insufficiency in order to extend the lifespan of KSD patients.

Association between Serum Klotho and Kidney Stones in US Middle-Aged and Older Individuals with Diabetes Mellitus: Results from 2007 to 2016 National Health and Nutrition Survey

INTRODUCTION

Kidney stones (KSs) are associated with hematuria and renal failure and pose a significant clinical and public health concern. Diabetes is associated with a higher risk of KSs. In addition, α-Klotho (Klotho), as a novel antiaging protein, is associated with kidney disease, diabetes, and complications and may participate in the pathological mechanism of KSs. However, studies that used large population-based database research are limited. Therefore, this study aimed to investigate whether or not KS prevalence is associated with serum Klotho levels in diabetic adults in the USA.

METHODS

This nationally representative cross-sectional study used data on diabetic adults in the USA aged 40-79 years from the National Health and Nutrition Examination Survey 2007-2016 cycles. Multivariate logistic regression models were used to calculate the association between Klotho and KS. Restricted cubic splines were used to further test for linearity and explore the shape of the dose-response association. Moreover, we performed stratified and interaction analyses to see if the relationship was stable in different subgroups.

RESULTS

Among the 3,537 diabetic patients included in this study (mean age of 61.4 years, consisting of 51.3% males), 543 participants (15.4%) suffered from KS. In the fully adjusted model, Klotho was negatively associated with KS (OR = 0.72; 95% CI: 0.54-0.96; p = 0.027). A negative relationship was observed between the occurrence of KS and Klotho (nonlinear: p = 0.560). Some differences in the association between Klotho and KS were found in stratified analyses; however, these differences lacked statistical significance.

CONCLUSIONS

Serum Klotho was negatively associated with the incidence of KS; when ln-transformed Klotho concentration increased by 1 unit, the risk of KS was 28% lower.

Relationship between hepatitis C and kidney stone in US females: Results from the National Health and Nutrition Examination Survey in 2007–2018

Background

The main objective of this study is to explore the effects of hepatitis C (HCV) on the prevalence rate of kidney stones in US women.

Method

Dates for HCV infection and kidney stones were collected from National Health and Nutrition Examination Survey (NHANES) database, a cross-sectional study. The analysis samples included adults aged ≥20 years and women from six consecutive cycles of the NHANES 2007–2018. The association between HCV infection and kidney stones was performed by using logistic regression models. Subgroup analyses were conducted to find sensitive crowds.

Results

A total of 13,262 participants were enrolled, including 201 infected with HCV. After adjustment for potential confounders, we revealed a positive relationship between HCV and kidney stones (OR = 1.70, 95%CI:1.13–2.56). The crowds' statistically significant difference was characterized by other races (OR = 8.17, 95%CI:1.62–41.22) and BMI within 25–29.9 kg/m2 (OR = 2.45, 95%CI:1.24–4.83).

Conclusions

HCV infection may affect the prevalence of urolithiasis in US women, even the causal relationship remains unclear, the relation deserves special attention. We considered such a study an ideal way to begin exploring the effects of HCV on kidney stones.

The Association of Urine Creatinine With Kidney Stone Prevalence in US Adults: Data From NHANES 2009-2018

Background

The primary objective of this project is to explore the association of urine creatinine (UCR) with the prevalence rate of kidney stones.

Method

The National Health and Nutrition Examination Survey (NHANES) database was employed to conduct a cross-sectional study. The analysis samples included adults aged ≥20 years from five consecutive cycles of the NHANES 2009–2018. The association between UCR and kidney stones was detected using univariate and multivariate logistic regression analyses. Further, subgroup analyses were performed to evaluate the subgroup effects.

Results

After adjustment for all confounders, multiple logistic regression analysis revealed a weak positive relationship between UCR and kidney stone (OR = 1.015, 95% CI: 1.008–1.021). In the subgroup analysis stratified by sex, age, or race, the risk further increased in men (OR = 1.014, 95% CI: 1.005–1.023), women (OR = 1.015, 95% CI: 1.005–1.025), white race (OR = 1.022, 95% CI: 1.013–1.030), aged 40–59 years (OR = 1.017, 95% CI: 1.006–1.028), and aged 60–80 years (OR = 1.017, 95% CI: 1.006–1.028).

Conclusions

Our results confirmed a moderately increased risk of kidney stone formation attributed to high levels of UCR, especially in middle-aged and older adults and the white race. However, because of the cross-sectional design of the study, causal inferences cannot be made.

Animal, Human, and 23Na MRI Imaging Evidence for the Negative Impact of High Dietary Salt in Children

PURPOSE OF THE REVIEW

Conditions typically prevalent in adults such as hypertension, kidney stones, osteoporosis, and chronic kidney disease are increasing among adolescents and young adults (AYA). The purpose of this review is to describe the association of these conditions to a high salt diet among pediatric patients.

RECENT FINDINGS

We present animal, human, and 23Na MRI evidence associated with the negative impact of high dietary salt in children. Special focus is placed on novel 23Na MRI imaging which reveals the important concept of a third compartment for sodium storage in soft tissue. Finally, we make recommendations on who should not be on a low salt diet.

SUMMARY

A high salt intake predisposes children and AYA to considerable morbidity. We exhort the reader to engage in advocacy efforts to curve the incidence and prevalence of high salt-related life-limiting conditions.

Normocalcemic Primary Hyperparathyroidism: Need for a Standardized Clinical Approach

Since normocalcemic primary hyperparathyroidism (NHPT) was first defined at the Third International Workshop on the Management of Asymptomatic Primary Hyperparathyroidism in 2008, many papers have been published describing its prevalence and possible complications. Guidelines for the management of this condition are still lacking, and making the diagnosis requires fulfillment of strict criteria. Recent studies have shown that intermittent oscillations of serum calcium just below and slightly above the normal limits are very frequent, therefore challenging the assumption that serum calcium must be consistently normal to make the diagnosis. There is debate if these variations in serum calcium outside the normal range should be included under the rubric of NHPT or, rather, a milder form of classical primary hyperparathyroidism. Innovative approaches to define NHPT have been proposed that still need to be validated in prospective studies. Non-classical complications, especially cardiovascular complications, have been associated with NHPT, indicating that hyperparathyroidism may be a cardiovascular risk factor. New associations between parathyroid hormone (PTH) and several other comorbidities have also been reported from observational studies, suggesting that excessive PTH secretion might cause tissue dysfunction independent of serum calcium. Heterogeneous studies using different definitions of NHPT, however, make it difficult to draw definitive conclusions regarding the role of PTH excess when complications other than osteoporosis or kidney stones are described. This review will focus on clinical aspects and suggest an approach to NHPT.

High Rate of Occult Urolithiasis in Normocalcemic Primary Hyperparathyroidism

INTRODUCTION

Normocalcemic primary hyperparathyroidism (NPHPT) is characterized by elevations in serum parathyroid hormone levels in the presence of normal serum calcium concentrations after exclusion of secondary hyperparathyroidism. We have previously demonstrated no differences in the prevalence of clinically active urolithiasis between NPHPT and hypercalcemic asymptomatic PHPT, and that it is significantly higher in postmenopausal osteoporotic women with NPHPT in comparison to women with normal serum PTH and calcium concentrations. Few studies have addressed the occurrence of silent or occult kidney stones in asymptomatic hypercalcemic PHPT, but no data are available for NPHPT.

OBJECTIVE

To determine the presence of occult urolithiasis in NPHPT patients using routine abdominal ultrasonography.

METHODS AND RESULTS

We studied 35 patients with NPHPT (mean age 63.2 ± 10.7 years, 96% women; serum PTH 116.5 ± 39.2 pg/mL, 25OHD 38.5 ± 6.82 ng/mL, total calcium 9.1 ± 0.56 mg/dL; albumin 4.02 ± 0.37 g/dL; BUN 34.35 ±10.23 mg/dL; p = 3.51 ± 0.60 mg/dL; estimated glomerular filtration rate 88.44 ± 32.45 mL/min/1.73 m2, and 24-h urinary calcium excretion 140.6 ± 94.3 mg/24 h). The criteria for the diagnosis of NPHPT were as follows: serum PTH above the reference range (11-65 pg/mL), normal albumin-corrected serum calcium concentrations, normal 24-h urinary calcium excretion, serum 25OHD above 30 ng/mL, estimated GFR (MDRD) above 60 mL/min/1.73 m2 (with the exclusion of medications such as thiazide diuretics, lithium, bisphosphonates, and denosumab), a history of clinical symptoms of urolithiasis, and a family history of kidney stones. Thirty-five patients were evaluated and 25 of them met the inclusion criteria. Five patients presented nephrolithiasis corresponding to 20% of the study population. There were no statistically significant differences in any of the clinical or laboratory variables studied between patients with or without urolithiasis, although mean serum PTH levels were higher in patients with stones (180.06 ± 126.48 vs. 100.72 ± 25.28 pg/mL, p = 0.1). The size of the stones ranged from 0.6 to 0.9 cm and all of the stones were located in the renal pelvis.

CONCLUSION

We found a high prevalence of occult kidney stones in NPHPT patients, similar to what is observed in clinically manifested urolithiasis, in hypercalcemic PHPT.

Exploring the Association of Asthma with Urinary Stone Disease: Results from the National Health and Nutrition Examination Survey 2007-2014

BACKGROUND

The prevalence of urinary stone disease (USD) and asthma is rising and has recently been associated in a pediatric population.

OBJECTIVE

To investigate the association between asthma and USD in a nationally representative adult population.

DESIGN, SETTING, AND PARTICIPANTS

We analyzed the National Health and Nutrition Examination Survey 2007-2014, a US population-based cross-sectional study. A history of asthma and USD was obtained by self-report to questionnaires. USD severity was represented by graded stratification into non-stone formers, single stone formers, and recurrent stone formers (>2 stones).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Odds ratios (ORs) for asthma were calculated for respondents with USD and separately for the graded USD groups. Survey-weighted logistic regression models included adjustments for demographics (model A), medical information (model B), and for relevant medications (model C).

RESULTS AND LIMITATIONS

A total of 20 906 participants aged ≥20 yr were included in the analysis. Of these, 9.2% reported of having a history of kidney stones. Logistic regression analysis adjusted for demographics, medical conditions, and medications showed that stone formers had significantly increased odds of asthma (odds ratio=1.23; 95% confidence interval: 1.03-1.47; p=0.023). Separate logistic regression analysis demonstrated a graded association between single and recurrent stone formers and the odds of having asthma (p=0.01), which remained significant in the 20-50-yr-old population and the diabetic population, especially for recurrent stone formers. Causal relationships were limited by cross-sectional nature of the study.

CONCLUSIONS

Increasing severity of USD is associated with an increase in odds for asthma among American adults, providing impetus for future studies into the mechanisms explaining this phenomenon.

PATIENT SUMMARY

In this report, we looked at self-reported histories of asthma and urinary stone disease (USD) using information from a large US population. We found that asthma was associated with USD; however, further studies are needed to elucidate this relationship.

Current and potential applications of host-defense peptides and proteins in urology

The use of antibiotics has become increasingly disfavored as more multidrug resistant pathogens are on the rise. A promising alternative to the use of these conventional drugs includes antimicrobial peptides or host-defense peptides. These peptides typically consist of short amino acid chains with a net cationic charge and a substantial portion of hydrophobic residues. They mainly target the bacterial cell membrane but are also capable of translocating through the membrane and target intracellular components, making it difficult for bacteria to gain resistance as multiple essential cellular processes are being targeted. The use of these peptides in the field of biomedical therapies has been examined, and the different approaches to using them under various settings are constantly being discovered. In this review, we discuss the current and potential applications of these host-defense peptides in the field of urology. Besides the use of these peptides as antimicrobial agents, the value of these biological molecules has recently been expanded to their use as antitumor and anti-kidney-stone agents.

Metabolic Syndrome and Nephrolithiasis Risk: Should the Medical Management of Nephrolithiasis Include the Treatment of Metabolic Syndrome?

This article reviews the relationship between metabolic syndrome (MetS) and nephrolithiasis, as well as the clinical implications for patients with this dual diagnosis. MetS, estimated to affect 25% of adults in the United States, is associated with a fivefold increase in the risk of developing diabetes, a doubling of the risk of acquiring cardiovascular disease, and an increase in overall mortality. Defined as a syndrome, MetS is recognized clinically by numerous constitutive traits, including abdominal obesity, hypertension, dyslipidemia (elevated triglycerides, low high-density lipoprotein cholesterol), and hyperglycemia. Urologic complications of MetS include a 30% higher risk of nephrolithiasis, with an increased percentage of uric acid nephrolithiasis in the setting of hyperuricemia, hyperuricosuria, low urine pH, and low urinary volume. Current American Urological Association and European Association of Urology guidelines suggest investigating the etiology of nephrolithiasis in affected individuals; however, there is no specific goal of treating MetS as part of the medical management. Weight loss and exercise, the main lifestyle treatments of MetS, counter abdominal obesity and insulin resistance and reduce the incidence of cardiovascular events and the development of diabetes. These recommendations may offer a beneficial adjunctive treatment option for nephrolithiasis complicated by MetS. Although definitive therapeutic recommendations must await further studies, it seems both reasonable and justifiable for the urologist, as part of a multidisciplinary team, to recommend these important lifestyle changes to patients with both conditions. These recommendations should accompany the currently accepted management of nephrolithiasis.

The Risk of Coronary Heart Disease in Patients with Kidney Stones: A Systematic Review and Meta-analysis

Background:

The reported risk of coronary heart disease (CHD) in patients with a history of kidney stones is conflicting.

Aims:

The objective of this meta-analysis was to assess the association between a history of kidney stones and CHD risk.

Materials and Methods:

A literature search was performed using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from inception until April 04, 2014. Studies that reported odds ratios or hazard ratios comparing the risk of CHD in patients with a history of kidney stones versus those without a history of kidney stones were included. Pooled risk ratios (RRs) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method.

Results:

Seven study populations from four cohort studies and one cross-sectional study were identified and included in the data analysis. The pooled risk ratio (RR) of CHD in patients with kidney stones was 1.24 (95% CI, 1.10-1.40). This result remained significant (RR, 1.23 [95% CI, 1.08-1.41]) when the sensitivity analysis was restricted to only cohort studies. A history of kidney stones was associated with increased CHD risk in females (RR, 1.43 [95% CI, 1.12-1.82]), whereas the association was not significant in males (RR, 1.14 [95% CI, 0.94-1.38]).

Conclusions:

Our study demonstrates a statistically significant increased risk of CHD in female patients with prior kidney stones. This finding suggests that a history of kidney stones is a risk factor for CHD in females and may impact clinical management.

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.