Assessment of the combination of temperature and relative humidity on kidney stone presentations

Sex-Specific Association of Ambient Temperature With Urine Biomarkers in Southwest Coastal Bangladesh

Introduction

Men are vulnerable to ambient heat-related kidney disease burden; however, limited evidence exists on how vulnerable women are when exposed to high ambient heat. We evaluated the sex-specific association between ambient temperature and urine electrolytes, and 24-hour urine total protein, and volume.

Methods

We pooled a longitudinal 5624 person-visits data of 1175 participants' concentration and 24-hour excretion of urine electrolytes and other biomarkers (24-hour urine total protein and volume) from southwest coastal Bangladesh (Khulna, Satkhira, and Mongla districts) during November 2016 to April 2017. We then spatiotemporally linked ambient temperature data from local weather stations to participants' health outcomes. For evaluating the relationships between average ambient temperature and urine electrolytes and other biomarkers, we plotted confounder-adjusted restricted cubic spline (RCS) plots using participant-level, household-level, and community-level random intercepts. We then used piece-wise linear mixed-effects models for different ambient temperature segments determined by inflection points in RCS plots and reported the maximum likelihood estimates and cluster robust standard errors. By applying interaction terms for sex and ambient temperature, we determined the overall significance using the Wald test. Bonferroni correction was used for multiple comparisons.

Results

The RCS plots demonstrated nonlinear associations between ambient heat and urine biomarkers for males and females. Piecewise linear mixed-effects models suggested that sex did not modify the relationship of ambient temperature with any of the urine parameters after Bonferroni correction (P < 0.004).

Conclusion

Our findings suggest that women are as susceptible to the effects of high ambient temperature exposure as men.

High ambient temperature impact on the pattern of emergency-room visits due to renal colic in the Middle East

Urolithiasis has a seasonal pattern, with an established increase in incidence during the summer months. This study aims to assess the impact of high ambient temperatures on emergency room (ER) visits related to renal colic (RC) in a Middle Eastern country over the past decade. Population data were extracted using the MDClone Big Data platform. We recorded demographic and clinical data on all RC-associated ER visits from January 2012 to April 2023 and calculated the heat index (HI) that combines daily average coastal plane temperatures and humidity percentages. There was a total of 12,770 ER visits (median age 48 years, 9,236 (72%) males). The number of visits increased during the hottest months (July-October), with the highest numbers recorded during August. The number of visits remained stable throughout the study. We identified a linear association between humidity and the incidence of ER visits (p = 0.002), and a non-linear association between ambient temperature (p < 0.0001) and HI (p < 0.0001). There was a direct relationship between high temperatures and ER visits on the same day (risk ratio [RR]: 1.75, p = 0.036), with a 2-day lag (RR: 1.123, p = 0.024). In Conclusion, there is a significant relationship between temperature, humidity, HI, and the number of ER visits due to RC. Adjusted resource allocation and healthcare workforce availability are essential for managing additional cases during heat waves. Clinical implications: Increased demand is expected during heatwaves and within a 2-day lag, emphasizing the importance of proactive strategies to effectively manage RC patients.

Pathophysiology and Main Molecular Mechanisms of Urinary Stone Formation and Recurrence

Kidney stone disease (KSD) is one of the most common urological diseases. The incidence of kidney stones has increased dramatically in the last few decades. Kidney stones are mineral deposits in the calyces or the pelvis, free or attached to the renal papillae. They contain crystals and organic components, and they are made when urine is supersaturated with minerals. Calcium-containing stones are the most common, with calcium oxalate as the main component of most stones. However, many of these form on a calcium phosphate matrix called Randall's plaque, which is found on the surface of the kidney papilla. The etiology is multifactorial, and the recurrence rate is as high as 50% within 5 years after the first stone onset. 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. This review aims to understand the pathophysiology and the main molecular mechanisms known to date to prevent recurrences, which requires behavioral and nutritional interventions, as well as pharmacological treatments that are specific to the type of stone.

Climate change and kidney stones

PURPOSE OF REVIEW

Kidney stones affect an increasing proportion of the population. We suggest that these trends are in part influenced by exposure to higher temperatures as a result of climate change and urbanization. The changing epidemiology of kidney stones is a topic worthy of discussion due to the economic and healthcare burden the condition poses as well as the quality-of-life disruption faced by individuals with kidney stones.

RECENT FINDINGS

The relationship between heat and kidney stones is well supported. Exposure to high temperatures has been shown to increase risk for stone development within a short time frame. Effects are modified by factors such as sex, comorbid conditions, and population vulnerability and adaptability. Urban heat islands (UHIs) likely exaggerate the effect of increasing global surface temperature. The concentration of UHIs often coincides with historic redlining practices in the United States, potentially contributing to observed disparities in kidney health among minoritized populations. As global surface temperature increases and urbanization trends continue, a greater proportion of the world's population is exposed to significant temperature extremes each year, leading to the expectation that kidney stone prevalence will continue to increase.

SUMMARY

This work describes the effect of increasing global surface temperature as a result of climate change on kidney stone disease and kidney health. These effects may result in further perpetuation of significant kidney stone related social disparities. We suggest strategies to mitigate the effects of heat exposure on stone formation.

Analysis, treatment modality and demographic characteristics of urolithiasis patients visiting Korle-Bu Teaching Hospital in Ghana

Background

Globally urolithiasis is on the rise and gradually becoming a public health concern due to the associated complications. This study reviewed the demographic characteristics, the chemical composition of stones, treatment modality and duration of hospitalisation of urolithiasis patients at Korle-Bu Teaching Hospital, Accra, Ghana.

Materials and Methods

This was a retrospective study conducted between March 2019 and April 2022. Data from consecutive patients treated for urolithiasis were used for this study. Data on demographic characteristics, stones chemical composition, urine factors, urolithiasis treatment modality and duration of hospital stay after therapy were collated and analysed using descriptive and inferential approaches.

Results

The age of the patients ranged from 2 to 75 years with a mean of 45 (±13.4). The predominant age group for stone formation was 30-39 years - 52(26.3%). Urolithiasis was common among patients in the formal employment sector: 81(40.9%). All stones had two or more chemical compositions, with the combination of calcium oxalate monohydrate, calcium oxalate dihydrate and uric acid being the predominant stone type: 88(57.5%). Ureteroscopy with semi-rigid and Percutaneous nephrolithotomy were the predominant treatment modalities: 105(53.0%) and 74(37.4%), respectively. Escherichia coli was responsible for most urinary tract infections in urolithiasis patients 8(4.0%) and the least duration of hospital stay after the procedure was associated with the use of semi-rigid ureteroscope as the treatment modality with a median duration of 2 days (1-2 days) with P < 0.0001.

Conclusions

Urolithiasis was predominant among professionals in the formal sector. All stones were mixed with Calcium oxalate monohydrate, calcium oxalate dihydrate, and uric acid combination being the majority. Ureteroscopy with semi-rigid and percutaneous nephrolithotomy were the common treatment modality.

Short-term impact of extreme temperatures, relative humidity and air pollution on emergency hospital admissions due to kidney disease and kidney-related conditions in the Greater Madrid area (Spain)

While some studies report a possible association between heat waves and kidney disease and kidney-related conditions, there still is no consistent scientific consensus on the matter or on the role played by other variables, such as air pollution and relative humidity. Ecological retrospective time series study 01-01-2013 to 31-12-2018). Dependent variables: daily emergency hospitalisations due to kidney disease (KD), acute kidney injury (AKI), lithiasis (L), dysnatraemia (DY) and hypovolaemia (HPV). Independent variables: maximum and minimum daily temperature (Tmax, Tmin, °C), and daily relative humidity (RH, %). Other variables were also calculated, such as the daily temperature for risk of kidney disease (Theat, °C) and low daily hazardous relative humidity (HRH%). As variables of air pollution, we used the daily mean concentrations of PM10, PM2.5, NO2 and O3 in μg/m3. Based on these, we then calculated their daily excesses over World Health Organisation (WHO) guideline levels (hPM10, hPM2.5, hNO2 and hO3 respectively). Poisson family generalised linear models (GLMs) (link = log) were used to calculate relative risks (RRs), and attributable risks and attributable admissions. In the models, we controlled for the covariates included: seasonalities, trend, autoregressive component, day of the week, month and year. A statistically significant association was found between Theat and all the dependent variables analysed. The greatest AKI disease burden was attributable to Theat (2.2 % (1.7, 2.6) of attributable hospital admissions), followed by hNO2 (1.7 % (0.9, 3.4)) and HRH (0.8 (0.6, 1.1)). In the case of hypovolaemia and dysnatraemia, the greatest disease burden again corresponded to Theat, with 6.9 % (6.2, 7.6) and 5.7 (4.8, 6.6) of attributable hospital admissions respectively. Episodes of extreme heat exacerbate daily emergency hospital admissions due to kidney disease and kidney-related conditions; and attributable risks are likewise seen for low relative humidity and high ozone levels.

Projection of high temperature-related burden of kidney disease in Australia under different climate change, population and adaptation scenarios: population-based study

Background

The dual impacts of a warming climate and population ageing lead to an increasing kidney disease prevalence, highlighting the importance of quantifying the burden of kidney disease (BoKD) attributable to high temperature, yet studies on this subject are limited. The study aims to quantify the BoKD attributable to high temperatures in Australia across all states and territories, and project future BoKD under climatic, population and adaptation scenarios.

Methods

Data on disability-adjusted-life-years (DALYs) due to kidney disease, including years of life lost (YLL), and years lived with disability (YLD), were collected during 2003-2018 (baseline) across all states and territories in Australia. The temperature-response association was estimated using a meta-regression model. Future temperature projections were calculated using eight downscaled climate models to estimate changes in attributable BoKD centred around 2030s and 2050s, under two greenhouse gas emissions scenarios (RCP4.5 and RCP8.5), while considering changes in population size and age structure, and human adaptation to climate change.

Findings

Over the baseline (2003-2018), high-temperature contributed to 2.7% (Standard Deviation: 0.4%) of the observed BoKD in Australia. The future population attributable fraction and the attributable BoKD, projected using RCP4.5 and RCP8.5, showed a gradually increasing trend when assuming no human adaptation. Future projections were most strongly influenced by the population change, with the high temperature-related BoKD increasing by 18.4-67.4% compared to the baseline under constant population and by 100.2-291.2% when accounting for changes in population size and age structure. However, when human adaptation was adopted (from no to partial to full), the high temperature-related BoKD became smaller.

Interpretation

It is expected that increasing high temperature exposure will substantially contribute to higher BoKD across Australia, underscoring the urgent need for public health interventions to mitigate the negative health impacts of a warming climate on BoKD.

Funding

Australian Research Council Discovery Program.

Role of Climate Change in Urologic Health: Kidney Stone Disease

Kidney stones are rising in incidence and prevalence worldwide. Given the temperature dependence of kidney stone presentations, climate change is projected to further increase the burden of disease for individuals and society. PATIENT SUMMARY: This mini-review reports current knowledge on climate change in relation to kidney stone disease. Kidney stones are more common in patients living in parts of the world that are hotter and more humid. Kidney stone problems are also more common after periods of high heat, which have a greater impact on men than on women. As temperatures rise with climate change, it is likely that the occurrence of kidney stones and the costs associated with their diagnosis and treatment will increase as well.

Optimal heat stress metric for modelling heat-related mortality varies from country to country

Combined heat and humidity is frequently described as the main driver of human heat-related mortality, more so than dry-bulb temperature alone. While based on physiological thinking, this assumption has not been robustly supported by epidemiological evidence. By performing the first systematic comparison of eight heat stress metrics (i.e., temperature combined with humidity and other climate variables) with warm-season mortality, in 604 locations over 39 countries, we find that the optimal metric for modelling mortality varies from country to country. Temperature metrics with no or little humidity modification associates best with mortality in ~40% of the studied countries. Apparent temperature (combined temperature, humidity and wind speed) dominates in another 40% of countries. There is no obvious climate grouping in these results. We recommend, where possible, that researchers use the optimal metric for each country. However, dry-bulb temperature performs similarly to humidity-based heat stress metrics in estimating heat-related mortality in present-day climate.

Association between circadian syndrome and the prevalence of kidney stones in overweight adults: a cross-sectional analysis of NHANES 2007-2018

OBJECTIVE

To explore the association between circadian syndrome (CircS) and the prevalence of kidney stones in overweight people.

MATERIALS AND METHODS

A cross-sectional analysis was conducted based on the NHANES 2007-2018. Overweight people aged ≥ 20 years were the target population. Three multivariable logistic regression models were built to examine the association between CircS and kidney stones. Subgroup analysis based on age, gender, and race were also employed. Interaction and stratification analysis was also conducted to identify whether some factors modify the association.

RESULT

A total of 4,603 overweight participants were included in the study. The multivariable logistic regression suggested that CircS was positively associated with the prevalence of kidney stones (OR = 1.422, 95% CI 1.057 to 1.912). The subgroup analysis showed that the association was more obvious in females (OR = 1.604, 95% CI 1.023 to 2.516) or in the population aged 35 to 49 years old (OR = 2.739, 95% CI 1.428 to 5.254). Additionally, the same trend was present when people were Mexican American (OR = 3.834, 95% CI 1.790 to 8.215) or other races (OR = 4.925, 95% CI 1.776 to 13.656). The interaction and stratification analysis showed that the results above were robust.

CONCLUSION

CircS was positively associated with the prevalence of kidney stones in overweight people, especially people as females, aged 35 to 49, and Mexican Americans.

The influence of climatic factors in the seasonal fluctuation of urolithiasis and the trend of stone disease management in the southern Taiwan

This study aims to analyze the effects of climate parameters on the number of urolithiasis treatments in our hospital and understand the effects of climate parameters on the prevalence of urolithiasis in southern Taiwan. We also look at trends associated with urolithiasis and treatments. Retrospectively reviewed the records of extracorporeal shockwave lithotripsy (ESWL), ureteroscopy (URS), retrograde intrarenal surgery (RIRS), and percutaneous nephrolithotripsy (PCNL) performed in our hospital from January 2012 to December 2018. Climate data for were collected from Central Weather Bureau. The monthly meteorological data included average temperatures, humidity, rainfall, sunshine hours, atmospheric pressure, and wind speed. Monthly numbers of patients undergoing stone management was positively correlated to average temperature (r = 0.657), relative humidity (r = 0.234), monthly rainfall (r = 0.261) and monthly sunshine hours (r = 0.348), while it was negatively correlated to atmospheric pressure (r = - 0.522). The multivariate linear regression model demonstrated temperature (ß = 10.682, 95% CI 6.178-14.646, p < 0.001) and Relative humidity (ß = - 95% CI - 5.233- - 1.216, p = 0.002) to be independently related to numbers of stone treatment. The data also revealed a rising prevalence of urolithiasis with an associated increase in the number of interventions, with fewer ESWL (74.0-49.4%). Temperature and relative humidity are associated with monthly numbers of stone treatment. Ambient temperature is the most critical climate factor affecting the prevalence of symptomatic urolithiasis and intention of active stone removal in southern Taiwan.

Associations between short-term temperature exposure and kidney-related conditions in New York State: The influence of temperature metrics across four dimensions

BACKGROUND

Evidence describing the relationship between short-term temperature exposure and kidney-related conditions is insufficient. It remains unclear how temperature specification affects estimation of these associations. This study aimed to assess associations between short-term temperature exposure and seven kidney-related conditions and to evaluate the influence of temperature specification.

METHODS

We obtained data on hospital encounters in New York State (2007-2016). We assessed associations with a case-crossover design using conditional logistic regression with distributed lag non-linear models. We compared model performance (i.e., AIC) and association curves using 1) five temperature spatial resolutions; 2) temperature on an absolute versus relative scale; 3) seven temperature metrics incorporating humidity, wind speed, and/or solar radiation; and 4) five intraday temperature measures (e.g., daily minimum and daytime mean).

RESULTS

We included 1,209,934 unplanned adult encounters. Temperature metric and intraday measure had considerably greater influence than spatial resolution and temperature scale. For outcomes not associated with temperature exposure, almost all metrics or intraday measures showed good model performance; for outcomes associated with temperature, there were meaningful differences in performance across metrics or intraday measures. For parsimony, we modelled daytime mean outdoor wet-bulb globe temperature, which showed good performance for all outcomes. At lag 0-6 days, we observed increased risk at the 95^th percentile of temperature versus the minimum morbidity temperature for acute kidney failure (odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.09, 1.69), urolithiasis (OR = 1.41, 95% CI: 1.16, 1.70), dysnatremia (OR = 1.26, 95% CI: 1.01, 1.59), and volume depletion (OR = 1.88, 95% CI: 1.41, 2.51), but not for glomerular diseases, renal tubulo-interstitial diseases, and chronic kidney disease.

CONCLUSIONS

High-temperature exposure over one week is a risk factor for acute kidney failure, urolithiasis, dysnatremia, and volume depletion. The differential model performance across temperature metrics and intraday measures indicates the importance of careful selection of exposure metrics when estimating temperature-related health burden.

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.

Ambient heat stress and urolithiasis attacks in China: Implication for climate change

BACKGROUND

Although the existing studies have suggested a significant association between high temperatures and urolithiasis, no nationwide studies have quantified the burden attributable to environmental heat stress and explored how the urolithiasis burden would vary in a warming climate.

METHODS

We collected data on urolithiasis attacks from 137 hospitals in 59 main cities from 20 provincial regions of China from 2000 to 2020. An individual-level case-crossover analysis was conducted to estimate the effect of daily wet-bulb globe temperature (WBGT), a heat stress index combining temperature and humidity, on urolithiasis attacks. Stratified analyses were performed by region, age, and sex. We further quantified the future WBGT-related burden of urolithiasis from the Coupled Model Intercomparison Project Phase 6 under three Shared Socioeconomic Pathway (SSP) scenarios.

RESULTS

In total, 118,180 urolithiasis patients were evaluated. The exposure-response curve for the association between WBGT and urolithiasis attacks was J-shaped, with a significantly increased risk for WBGT higher than 14.8 °C. The middle-aged and elderly group (≥45 years old) had a higher risk of WBGT-related urolithiasis attacks than in the younger group, while no significant sex difference was observed. The attributable fraction (AF) due to high WBGT would increase from 10.1% in the 2010s to 16.1% in the 2090s under the SSP585 scenario. Warm regions were projected to experience disproportionately higher AFs and larger increments in the future.

CONCLUSIONS

This nationwide investigation provides novel evidence on the acute effect of high WBGT on urolithiasis attacks and demonstrates the increasing disease burden in a warming climate.

The Risk Factors for Radiolucent Nephrolithiasis among Workers in High-Temperature Workplaces in the Steel Industry

Workers in high-temperature workplaces with inadequate water supply may exhibit symptoms of chronic dehydration and have increased risk of nephrolithiasis. The aim of this study was to investigate the risk of radiolucent stone formation among workers in a high-temperature workplace and the related risk factors associated with the condition. We collected data from 1681 workers in a steel factory in Southern Taiwan who underwent regular health examinations. Radiolucent stones were defined as positive findings on ultrasound with negative radiographic images. The prevalences of nephrolithiasis and radiolucent stones in this study were 12.0% and 5.1%, respectively. Heat exposure and age were two major risk factors influencing the probability of radiolucent stones. We combined the age and heat exposure into four groups (over and under 35 years of age with and without heat exposure) in a logistic regression. For workers younger than 35 years, the odds ratio of radiolucent stones was 2.695 (95% confidence interval: 1.201-6.049) in workers with heat exposure compared to workers without. Our investigation further demonstrated that heat exposure was a main risk factor for radiolucent stone formation. In conclusion, our identification of heat exposure as an independent factor for radiolucent stone development in steel workers highlights the need for attention to be paid to those working in similar environments.

Associations Between Ambient Extreme Heat Exposure and Emergency Department Visits Related to Kidney Disease

RATIONALE & OBJECTIVE

Extreme heat exposure is associated with multiple diseases. However, our current understanding of the specific impact of extreme heat exposure on kidney disease is limited.

STUDY DESIGN

Case-crossover study.

SETTING & PARTICIPANTS

1,114,322 emergency department (ED) visits with a principal diagnosis of kidney disease were identified in New York state, 2005-2013.

EXPOSURE

Extreme heat exposure was defined as when the daily temperature exceeded the 90th percentile temperature of that month during the study period in the county.

OUTCOME

ED visits with a principal diagnosis of kidney disease and its subtypes (ICD-9 [International Classification of Diseases, Ninth Revision] codes 580-599, 788).

ANALYTICAL APPROACH

Extreme heat exposure on the ED visit days was compared with extreme heat exposure on control days using a conditional logistic regression model, controlling for humidity, air pollutants, and holidays. The excess risk of kidney disease was calculated for a week (lag days 0-6) after extreme heat exposure during the warm season (May through September). We also stratified our estimates by sociodemographic characteristics.

RESULTS

Extreme heat exposure was associated with a 1.7% (lag day 0) to 3.1% (lag day 2) higher risk of ED visits related to kidney disease; this association was stronger with a greater number of extreme heat exposure days in the previous week. The association with extreme heat exposure lasted for an entire week and was stronger in the transitional months (ie, May and September; excess rates ranged from 1.8% to 5.1%) rather than the summer months (June through August; excess rates ranged from 1.5% to 2.7%). The strength of association was greater among those with ED visits related to acute kidney injury, kidney stones, and urinary tract infections. Age and sex may modify the association between extreme heat exposure and ED visits.

LIMITATIONS

Individual exposure to heat-how long people were outside or whether they had access to air conditioning-was unknown.

CONCLUSIONS

Extreme heat exposure was significantly associated with a dose-dependent greater risk of ED visits for kidney disease.

Ambient temperature, humidity, and urinary system diseases: a population-based study in Western China

Climate has received an increasing attention due to its adverse effects on human health, but the effects on the urinary system are still short of enough evidence. Therefore, we carry out this study to analyze the relationship between meteorological factors and urinary system health in arid areas of western China. In this study, the daily numbers of outpatients with the urinary system diseases from multiple hospitals in three cities in Gansu province (Lanzhou, Zhangye, and Tianshui city) were collected and used for analysis. The distributed lag non-linear models (DLNM) with a quasi-Poisson distribution were used to estimate the associations between meteorological factors and daily outpatients for urinary system diseases in these three cities, and then a multivariate meta-analysis was applied to pool the estimates of city-specific effects. We found that the ambient temperature (AT) and relative humidity (RH) were significantly associated with the outpatient visits of urinary system diseases. The effects of meteorological factors on outpatients with urinary system diseases for both males and females were statistically significant at different lag days. The higher AT and lower RH were associated with the higher risk of urinary system diseases. We also observed substantial lag effects of meteorological factors on outpatients for both males and females. Among all disease types, renal tubule-interstitial diseases had the strongest relationships with meteorological factors. Our results indicate that the higher AT and lower RH may increase the outpatient visits for urinary system diseases, with significant lag effects in semi-arid areas.

The Effectiveness Of Government Masking Mandates On COVID-19 County-Level Case Incidence Across The United States, 2020

Evidence for the effectiveness of masking on SARS-CoV-2 transmission at the individual level has accumulated, but the additional benefit of community-level mandates is less certain. In this observational study of matched cohorts from 394 US counties between March 21 and October 20, 2020, we estimated the association between county-level public masking mandates and daily COVID-19 case incidence. On average, the daily case incidence per 100,000 people in masked counties compared with unmasked counties declined by 23 percent at four weeks, 33 percent at six weeks, and 16 percent across six weeks postintervention. The beneficial effect varied across regions of different population densities and political leanings. The most concentrated effects of masking mandates were seen in urban counties; the benefit of the mandates was potentially stronger within Republican-leaning counties. Although benefits were not equally distributed in all regions, masking mandates conferred benefit in reducing community case incidence during an early period of the COVID-19 pandemic.

Exposure to Abnormally Hot Temperature and the Demand for Commercial Health Insurance

Using the China Health and Retirement Longitudinal Study, this paper studies the impact of abnormal hot temperature on residents' demand for commercial health insurance. The results show that for every 1°F rise in abnormal temperature, the probability of people buying commercial health insurance increased by 6%. Furthermore, the abnormal hot temperature has a more significant impact on the commercial health insurance demand of women, residents in the South and residents in the East. Channel analysis shows that abnormal hot temperature affects the demand for commercial health insurance through two channels: increasing residents' concern about climate risk and affecting health. This paper provides evidence for actively promoting sustainable development and improving the construction of medical security system.

The impact of heat on kidney stone presentations in South Carolina under two climate change scenarios

The risk of kidney stone presentations increases after hot days, likely due to greater insensible water losses resulting in more concentrated urine and altered urinary flow. It is thus expected that higher temperatures from climate change will increase the global prevalence of kidney stones if no adaptation measures are put in place. This study aims to quantify the impact of heat on kidney stone presentations through 2089, using South Carolina as a model state. We used a time series analysis of historical kidney stone presentations (1997–2014) and distributed lag non-linear models to estimate the temperature dependence of kidney stone presentations, and then quantified the projected impact of climate change on future heat-related kidney stone presentations using daily projections of wet-bulb temperatures to 2089, assuming no adaptation or demographic changes. Two climate change models were considered—one assuming aggressive reduction in greenhouse gas emissions (RCP 4.5) and one representing uninibited greenhouse gas emissions (RCP 8.5). The estimated total statewide kidney stone presentations attributable to heat are projected to increase by 2.2% in RCP 4.5 and 3.9% in RCP 8.5 by 2085–89 (vs. 2010–2014), with an associated total excess cost of ~ $57 million and ~ $99 million, respectively.

Hot weather as a risk factor for kidney disease outcomes: A systematic review and meta-analysis of epidemiological evidence

BACKGROUND

The occurrence or exacerbation of kidney disease has been documented as a growing problem associated with hot weather. The implementation of effective prevention measures requires a better understanding of the risk factors that increase susceptibility. To fill gaps in knowledge, this study reviews the current literature on the effects of heat on kidney-disease outcomes (ICD-10 N00-N39), including morbidity and mortality.

METHODS

Databases were systematically searched for relevant literature published between 1990 and 2020 and the quality of evidence evaluated. We performed random effects meta-analysis to calculate the pooled relative risks (RRs) of the association between high temperatures (and heatwaves) and kidney disease outcomes. We further evaluated vulnerability concerning contextual population characteristics.

RESULTS

Of 2739 studies identified, 91 were reviewed and 82 of these studies met the criteria for inclusion in a meta-analysis. Findings showed that with a 1 °C increase in temperature, the risk of kidney-related morbidity increased by 1% (RR 1.010; 95% CI: 1.009-1.011), with the greatest risk for urolithiasis. Heatwaves were also associated with increased morbidity with a trend observed with heatwave intensity. During low-intensity heatwaves, there was an increase of 5.9% in morbidity, while during high-intensity heatwaves there was a 7.7% increase. There were greater RRs for males, people aged ≤64 years, and those living in temperate climate zones. Similarly, for every 1 °C temperature increase, there was a 3% (RR 1.031; 95% CI: 1.018-1.045) increase in the risk of kidney-related mortality, which also increased during heatwaves.

CONCLUSIONS

High temperatures (and heatwaves) are associated with an elevated risk of kidney disease outcomes, particularly urolithiasis. Preventive measures that may minimize risks in vulnerable individuals during hot spells are discussed.

Advantages of Herbal Over Allopathic Medicine in the Management of Kidney and Urinary Stones Disease

Kidney and urinary stone disease (Nephrolithiasis and urolithiasis) are the condition where urinary stones or calculi are formed in the urinary tract. The problem of urinary stones is very ancient; these stones are found in all parts of the urinary tract, kidney, ureters, and the urinary bladder and may vary considerably in size. It is a common disease estimated to occur in approximately 12% of the population, with a recurrence rate of 70-81% in males and 47-60% in females. The treatment of kidney and urinary stone diseases such as a western (allopathy) medicine and surgery is now in trends. However, most people preferred plant-based (herbal) therapy because of the overuse of allopathic drugs, which results in a higher incidence rate of adverse or severe side effects. Therefore, people every year turn to herbal therapy because they believe plant-based medicine is free from undesirable side effects, although herbal medicines are generally considered to be safe and effective. In the present article, an attempt has been made to emphasize an herbal therapy is better than allopathic therapy for the management of the kidney and urinary stone disease.

Role of core body temperature in nephrolithiasis

OBJECTIVES

To assess the role of core body temperature in urinary stone formation using a large clinical dataset.

PATIENTS AND METHODS

We retrospectively collected 14 519 039 individual temperature measurements from 580 416 patients with medical history, laboratory values and medication history between 2013 and 2018 at a single institution. After exclusions and matching 2:1 (controls:cases) to account for confounding variables, 7104 patients with a history of urinary stones were identified.

RESULTS

Patients with a history of urinary stones (cases) had an elevated mean (SD) oral temperature compared to matched controls, at 36.666 (0.17) vs 36.659 (0.20)°C (P = 0.012). Logistic regression of matched samples showed that higher core body temperature was predictive of a history of nephrolithiasis (odds ratio 1.21, 95% confidence interval 1.04-1.4; P = 0.015).

CONCLUSION

Core body temperature was significantly higher in patients with a history of urinary stones compared to matched controls, contrary to the anticipated thermodynamic considerations leading to crystal aggregation. Given that the core body temperature is elevated, rather than decreased, thermodynamic process driving stone formation is unlikely.

Occupational kidney stones

PURPOSE OF REVIEW

Kidney stones are a common and preventable disorder. Certain occupations may increase risk for stone disease which will be discussed in this review. Few observational studies have examined this association.

RECENT FINDINGS

Some occupations prevent individuals from drinking enough fluids to maintain a dilute urine or to void when they need to. People may have poor access to fluids or to bathroom facilities. These issues pose a risk for stone disease and are exacerbated by those who work in warmer climates. Individuals who do more activity while working, especially outdoors, perspire more, leading to more concentrated urine. In more sedentary jobs, individuals are at a higher risk of metabolic syndrome and therefore have a higher risk for stones. Astronauts, who work in environments without gravity, mobilize calcium from bone, leading to a higher risk of stone disease.

SUMMARY

Proper fluid intake, more access to restrooms and increased use of potassium citrate may be the best options for those who encounter greater risk for stones because of their occupation.

Association of Social Distancing, Population Density, and Temperature With the Instantaneous Reproduction Number of SARS-CoV-2 in Counties Across the United States

IMPORTANCE

Local variation in the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) across the United States has not been well studied.

OBJECTIVE

To examine the association of county-level factors with variation in the SARS-CoV-2 reproduction number over time.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included 211 counties, representing state capitals and cities with at least 100 000 residents and including 178 892 208 US residents, in 46 states and the District of Columbia between February 25, 2020, and April 23, 2020.

EXPOSURES

Social distancing, measured by percentage change in visits to nonessential businesses; population density; and daily wet-bulb temperatures.

MAIN OUTCOMES AND MEASURES

Instantaneous reproduction number (Rt), or cases generated by each incident case at a given time, estimated from daily case incidence data.

RESULTS

The 211 counties contained 178 892 208 of 326 289 971 US residents (54.8%). Median (interquartile range) population density was 1022.7 (471.2-1846.0) people per square mile. The mean (SD) peak reduction in visits to nonessential business between April 6 and April 19, as the country was sheltering in place, was 68.7% (7.9%). Median (interquartile range) daily wet-bulb temperatures were 7.5 (3.8-12.8) °C. Median (interquartile range) case incidence and fatality rates per 100 000 people were approximately 10 times higher for the top decile of densely populated counties (1185.2 [313.2-1891.2] cases; 43.7 [10.4-106.7] deaths) than for counties in the lowest density quartile (121.4 [87.8-175.4] cases; 4.2 [1.9-8.0] deaths). Mean (SD) Rt in the first 2 weeks was 5.7 (2.5) in the top decile compared with 3.1 (1.2) in the lowest quartile. In multivariable analysis, a 50% decrease in visits to nonessential businesses was associated with a 45% decrease in Rt (95% CI, 43%-49%). From a relative Rt at 0 °C of 2.13 (95% CI, 1.89-2.40), relative Rt decreased to a minimum as temperatures warmed to 11 °C, increased between 11 and 20 °C (1.61; 95% CI, 1.42-1.84) and then declined again at temperatures greater than 20 °C. With a 70% reduction in visits to nonessential business, 202 counties (95.7%) were estimated to fall below a threshold Rt of 1.0, including 17 of 21 counties (81.0%) in the top density decile and 52 of 53 counties (98.1%) in the lowest density quartile.2.

CONCLUSIONS AND RELEVANCE

In this cohort study, social distancing, lower population density, and temperate weather were associated with a decreased Rt for SARS-CoV-2 in counties across the United States. These associations could inform selective public policy planning in communities during the coronavirus disease 2019 pandemic.

Geospatial context of social and environmental factors associated with health risk during temperature extremes: Review and discussion

This study reviews forty-six publications between 2008 and 2017 dealing with socio-environmental impacts on adverse health effects of temperature extremes, in a geospatial context. The review showed that most studies focus on extremely hot weather but lack analysis of how spatial heterogeneity across a region can influence cold mortality/morbidity. There are limitations regarding the use of temperature datasets for spatial analyses. Only a few studies have applied air temperature datasets with high spatial resolution to health studies, but none of these studies have used anthropogenic heat as a factor for analysis of health risk. In addition, the elderly is generally recognized as a vulnerable group in most studies, but the interaction between old age and temperature risk varies by location. Other socio-demographic factors such as low income, low education and accessibility to community shelters may also need to be considered in the future. There are only a few studies which investigate the interaction between temperature and air pollution in a geospatial context, despite the fact that this is a known interaction that can influence health risk under extreme weather. In conclusions, although investigation of temperature effects on health risk is already at the "mature stage", studies of socio-environmental influences on human health under extreme weather in a geospatial context is still being investigated. A comprehensive assessment is required to analyse how the spatial aspects of the geophysical and social environments can influence human health under extreme weather, in order to develop a better community plan and health protocols for disaster preparedness.

Influence of climate on the number of hospitalizations for nephrolithiasis in urban regions in Brazil

Introduction:

Nephrolithiasis has a worldwide prevalence of approximately 5 to 15%, and its occurrence is associated with age, sex, race, dietary habits, geographic location, climatic conditions, and other factors. The objective of the present study was to determine the association between climate and the number of hospitalizations for nephrolithiasis (NH) in Brazilian cities located in different climatic regions.

Methods:

We analyzed data from cities with tropical and subtropical climates. The effects of the lowest (LT), mean (MT), and highest (HT) monthly temperatures and relative humidity of the air (RH) were assessed.

Results:

A positive association was found between the number of hospitalizations for nephrolithiasis and temperature ((LT x NH; R²=0.218; P<0.0001) (MT x NH; R²=0.284; P<0.0001) (HT x NH; R²=0.317; P<0.0001)), and a negative association was found between the number of hospitalizations for nephrolithiasis and the relative humidity (RH x NH; R²=0.234; P<0.0001). Interactions were also observed between MT and RH with respect to their effects on the NH, as described by a linear model (NH = 4.688 + 0.296 x MT - 0.088 x RH). The NH was higher in cities with tropical climates than in cities with subtropical climates (82.4 ± 10.0 vs 28.2 ± 1.6; P<0.00001).

Conclusion:

There is an association between the NH and variations in temperature and relative humidity.

Association Between Daily Water Intake and 24-hour Urine Volume Among Adolescents With Kidney Stones

OBJECTIVE

To determine the association between daily water intake and 24-hour urine volume among adolescents with nephrolithiasis in order to estimate a "fluid prescription," the additional water intake needed to increase urine volume to a target goal.

METHODS

We conducted a secondary analysis of an ecological momentary assessment study that prospectively measured daily water intake of 25 adolescents with nephrolithiasis over 7 days. We identified 24-hour urine volumes obtained for clinical care within 12 months of water intake assessment. A linear regression model was fit to estimate the magnitude of the association between daily water intake and 24-hour urine volume, adjusting for age, sex, race, and daily temperature.

RESULTS

Twenty-two participants completed fifty-seven 24-hour urine collections within 12 months of the study period. Median daily water intake was 1.4 L (IQR 0.67-1.94). Median 24-hour urine volume was 2.01 L (IQR 1.20-2.73). A 1 L increase in daily water intake was associated with a 710 mL increase in 24-hour urine output (95%CI 0.55-0.87). Using the model output, the equation was generated to estimate the additional fluid intake needed fluid prescription (FP) to produce the desired increase in urine output (dUOP): FP = dUOP/0.71.

CONCLUSION

The FP equation (FP = dUOP)/0.71), which reflects the relationship between water intake and urine volume, could be used to help adolescents with nephrolithiasis achieve urine output goals to decrease stone recurrence.

Associations between ambient temperature and hepatobiliary and renal hospitalizations in California, 1999 to 2009

BACKGROUND

High ambient temperature has been linked to a number of types of morbidity, such as cardiovascular disease and dehydration. Fewer studies have explored specifically the relationship between ambient temperature and liver, kidney, and urinary system morbidity despite known biological impacts of extreme high temperatures on those systems.

OBJECTIVE

We assessed the relationship between temperature and hospitalizations related to selected renal system (urinary stones, urinary tract infections, septicemia, chronic kidney disease, and a composite of selected kidney diseases) and hepatobiliary (biliary tract disease, other liver diseases [e.g. cirrhosis], non-diabetic pancreatic disorders) ailments.

METHODS

We compiled data on daily hospitalization counts for hepatobiliary and renal system diseases in California for 1999 through 2009, and matched it with meteorological data. Relationships between temperature and admissions during the warm season (May-October) were assessed at the climate zone-level cumulative over 14 days following exposure using distributed lag non-linear models, with adjustment for time trends and relative humidity, then combined using random-effects meta-regression to create statewide estimates.

RESULTS

Higher mean temperatures in the warm season were associated with significant increases in renal admissions for urinary tract infection [% change per 10 °F: 7.3, 95% CI: 5.6, 9.1], septicemia [% increase: 2.9; 95% CI: 1.5, 4.3], urinary stones [% increase: 15.2; 95% CI: 10.3, 20.4], and composite kidney disease. Additionally, increased temperatures were linked to increased admissions for biliary tract disease, but lower risk of other liver diseases. Some differences in association by race/ethnicity and regional meteorology were observed.

CONCLUSIONS

Exposure to higher temperatures was associated with increased risk of multiple renal system hospitalization types, with additional links to specific hepatobiliary morbidities observed.

Sex differences in the temperature dependence of kidney stone presentations: a population-based aggregated case-crossover study

Previous studies assumed a uniform relationship between heat and kidney stone presentations. Determining whether sex and other characteristics modify the temperature dependence of kidney stone presentations has implications for explaining differences in nephrolithiasis prevalence and improving projections of the effect of climate change on nephrolithiasis. We performed an aggregated case-crossover study among 132,597 children and adults who presented with nephrolithiasis to 68 emergency departments throughout South Carolina from 1997 to 2015. We used quasi-Poisson regression with distributed lag non-linear models to estimate sex differences in the cumulative exposure and lagged response between maximum daily wet-bulb temperatures and emergent kidney stone presentations, aggregated at the ZIP-code level. We also explored interactions by age, race, payer, and climate. Compared to 10 °C, daily wet-bulb temperatures at the 99th percentile were associated with a greater increased relative risk (RR) of kidney stone presentations over 10 days for males (RR 1.73; 95% CI 1.56, 1.91) than for females (RR 1.15; 95% CI 1.01, 1.32; interaction P < 0.001). The shape of the lagged response was similar for males and females, with the greatest risk estimated for the 2 days following high temperatures. There were weak differences by age, race, and climatic zone, and no differences by payer status. The estimated risk of presenting emergently with kidney stones within 10 days of high daily wet-bulb temperatures was substantially greater among men than women, and similar between patients with public and private insurance. These findings suggest that the higher risk among males may be due to sexually dimorphic physiologic responses rather than greater exposure to ambient temperatures.

Pediatric Stone Disease

Once considered rare, pediatric nephrolithiasis has become a critical field of study in the last decade due to the rapid increase in incidence. Understanding the changing epidemiology and lifelong implications of pediatric stone disease is critically important to effectively manage the individual patient as well as identify risk factors for childhood onset that could be modified. Determining the role of diagnostic imaging in children is a unique challenge as limiting radiation and imaging stewardship should be priorities. Approaches to management have also changed, as technology continues to evolve and both medical and surgical options expand.

Escalating heat-stress mortality risk due to global warming in the Middle East and North Africa (MENA)

Climate change will substantially exacerbate extreme temperature and heatwaves. The impacts will be more intense across the Middle East and North Africa (MENA), a region mostly characterized by hot and arid climate, already intolerable for human beings in many parts. In this study, daily climate data from 17 fine-resolution Regional Climate Models (RCMs) are acquired to calculate wet-bulb temperature and investigate the mortality risk for people aged over 65 years caused by excessive heat stress across the MENA region. Spatially adaptive temperature thresholds are implemented for quantifying the mortality risk, and the analysis is conducted for the historical period of 1951-2005 and two future scenarios of RCP4.5 and RCP8.5 during the 2006-2100 period. Results show that the mortality risk will increase in distant future to 8-20 times higher than that of the historical period if no climate change mitigation is implemented. The coastal regions of the Red sea, Persian Gulf, and Mediterranean Sea indicate substantial increase in mortality risk. Nonetheless, the risk ratio will be limited to 3-7 times if global warming is limited to 2 °C. Climate change planning and adaptation is imperative for mitigating heat-related mortality risk across the region.