Gaps in kidney stone disease management: From clinical theory to patient reality

With nephrolithiasis projected to affect 25% of the global population in the next three decades, there is an urgent call for innovative management strategies to prevent and reduce stone recurrence. This study aims to explore the evolving management needs in nephrolithiasis from both patient and healthcare provider perspectives. An expert-collaborative online survey comprising 10 targeted questions on kidney stone management was developed and disseminated. This survey was designed to gather comprehensive insights from patients, physicians and dietician and other person in the field of nephrolithiasis. Analysis of responses from 120 participants, including 45 nephrologists, 38 dieticians, 11 urologists, and 14 kidney stones patients followed in our hospital, revealed critical insights. A significant 97.5% emphasized the necessity of optimizing daily water intake, and 94.1% recognized the need for practical dietary modifications. Additionally, 88.3% of respondents found timely hydration reminders beneficial. Notably, monitoring urine color and pH was valued by 85% and 84.3% of the participants, respectively. A striking disparity emerged in the perception of fatigue and wellness monitoring, with 65% of patients prioritizing fatigue monitoring, a view less shared by healthcare professionals. Similarly, 71% of patients deemed wellness monitoring essential, highlighting a gap in understanding between patients and their caregivers. This study underscores the critical need for more tailored guidance on hydration strategies and the promise of remote urine parameters monitoring in nephrolithiasis management. The findings strongly advocate for a patient-centered approach, aligning medical recommendations with patient lifestyles and experiences, to enhance the effectiveness of nephrolithiasis management.

The estrogenic reduction in water intake stimulated by dehydration involves estrogen receptor alpha and a potential role for GLP-1

It is well documented that estrogens inhibit fluid intake. Most of this research, however, has focused on fluid intake in response to dipsogenic hormone and/or drug treatments in euhydrated rats. Additional research is needed to fully characterize the fluid intake effects of estradiol in response to true hypovolemia. As such, the goals of this series of experiments were to provide a detailed analysis of water intake in response to water deprivation in ovariectomized female rats treated with estradiol. In addition, these experiments also tested if activation of estrogen receptor alpha is sufficient to reduce water intake stimulated by water deprivation and tested for a role of glucagon like peptide-1 in the estrogenic control of water intake. As expected, estradiol reduced water intake in response to 24 and 48 h of water deprivation. The reduction in water intake was associated with a reduction in drinking burst number, with no change in drinking burst size. Pharmacological activation of estrogen receptor alpha reduced intake. Finally, estradiol-treatment caused a leftward shift in the behavioral dose response curve of exendin-4, the glucagon like peptide-1 agonist. While the highest dose of exendin-4 reduced 10 min intake in both oil and estradiol-treated rats, the intermediate dose only reduced intake in rats treated with estradiol. Together, this series of experiments extends previous research by providing a more thorough behavioral analysis of the anti-dipsogenic effect of estradiol in dehydrated rats, in addition to identifying the glucagon like peptide-1 system as a potential bioregulator involved in the underlying mechanisms by which estradiol reduces water intake in the female rat.

Perceived dehydration impairs endurance cycling performance in the heat in active males

Dehydration of >3 % body mass impairs endurance performance irrespective of the individual's knowledge of their hydration status, but whether knowledge of hydration status influences performance at lower levels of dehydration is unknown. This study examined whether perception of hydration status influenced endurance performance. After familiarisation, nine active males (age 25 ± 2 y, V̇O2peak 52.5 ± 9.1 mL kg min-1) completed two randomised trials at 34 °C. Trials involved an intermittent exercise preload (8 × 10 min cycling/5 min rest), followed by a 15 min all-out cycling performance test. During the preload in both trials, water was ingested orally every 10 min (0.3 mL kg body mass-1), with additional water infused into the stomach via gastric feeding tube to produce dehydration of ∼1.5 % body mass pre-performance test. Participants were told intra-gastric infusion was manipulated to produce euhydration (0 % dehydration; Perceived-EUH) or dehydration (2 % dehydration; Perceived-DEH) pre-performance test, which was told to them pre-preload and confirmed after body mass measurement pre-performance test. Body mass loss during the preload (Perceived-EUH 1.6 ± 0.2 %, Perceived-DEH 1.7 ± 0.2 %; P = 0.459), heart rate, gastrointestinal temperature and RPE (P ≥ 0.110) were not different between trials. Thirst was greater at the end of the preload and performance test in Perceived-DEH (P ≤ 0.040). Work completed during the performance test was 5.6 ± 6.1 % lower in Perceived-DEH (187.4 ± 37.0 kJ vs. 176.9 ± 36.0 kJ; P = 0.038). These results suggest that at lower levels of dehydration (<2 % body mass), an individual's perception of their hydration status could impair their performance, as well as their thirst perception.

Seminal papers in urology: urinary volume, water and recurrences in idiopathic calcium nephrolithiasis: a 5-year randomized prospective study : Borghi L, Meschi T, Amato F, Briganti A, Novarini A, Giannini A. urinary volume, water and recurrences in idiopathic calcium nephrolithiasis: a 5-year randomized prospective study. The Journal of urology. 1996 Mar;155(3):839 - 43

Kidney stones, a persistent urological condition, continue to affect people globally. In this critical review, we examine the work of Borghi et al. who evaluated patients with idiopathic stone formation and randomised 99 patients to increased water intake (≥ 2 L/day) and 100 patients to usual care in a 5-year randomized controlled trial. The study examined baseline urine volume in individuals with idiopathic calcium stones, recurrence rates, and relevant biochemical factors. The study found reduced recurrence rate (12.1% vs. 27% (p = 0.008)), and time to recurrence with increased water intake (38.7 ± 13.2 months) vs. (25 ± 16.4 months) (p = 0.016). These findings inform clinical practice, contributing to the guideline recommendations that kidney stone patients should aim for fluid intake of at least 2.5 L per day to prevent stone recurrence.

Analysis of potential hydration opportunities during future football tournaments based on data from the 2018 FIFA World Cup

The World Cup is traditionally held oppressive thermal conditions. Therefore, teams should follow heat strain mitigation strategies, including optimal fluid ingestion. The objective of this analysis was to assess and visually communicate match-based World Cup player hydration opportunities and behaviors. Broadcast recordings of the 2018 World Cup (June-July) were analyzed. Descriptive data were reported for match duration, the number, type, and duration of breaks, and player-initiated hydration moments, as well as environmental conditions categorized as 'no thermal stress' and 'thermal heat stress.' The median number and interquartile range of total match breaks were 7 [5-8] during official breaks, with a duration of 42 [23-72] seconds. There were 2 [1-3] player-initiated hydration moments per game, with a duration of 77 [55-100] seconds. On top of the 29% (#126) of breaks in which drinking occurred, an additional 26% (#33) of self-initiated drinking was registered with a duration of 7 [4-28] seconds without an official break. There was no significant difference (P = 0.22) in self-initiated hydration between thermal conditions. Relative percentages showed suboptimal use of substitution (14%) and VAR (38%) breaks vs. injury breaks (75%). In conclusion, football players did not sufficiently use available breaks to hydrate.

Investigating the impact of an online hydration intervention in care homes using the COM-B model: a mixed methods study

BACKGROUND

Antimicrobial resistance is a serious threat to public health. To reduce antimicrobial resistance, interventions to reduce gram-negative infections, specifically urinary tract infections, are vital. Early evidence suggests increased fluid intake is linked with a reduction in UTIs and subsequently has potential to reduce antibiotic usage. Care homes have a high prevalence of UTIs and provide an opportunity in a closed setting to deliver an intervention focused on increasing fluid intake, where it is supported and monitored by health care workers. The study aimed to evaluate the impact and feasibility of an online staff focused intervention over a 30 day period to increase the hydration of care home residents with a view to reducing the burden of AMR in this setting.

METHODS

The study was a pre and post intervention with a sequential explanatory mixed methods design. The intervention was delivered online in 3 care homes, containing 3 main components underpinned by the COM-B model including hydration training, 7 structured drinks rounds and a hydration champion to change behaviour of care home staff. A pre and post questionnaire assessed the impact of the intervention on staff and data was collected on fluid intake, drinks rounds delivered to residents, UTIs, antibiotic used to treat UTIs, falls and hospitalisation. Descriptive statistics summarised and assessed the impact of the study. Focus groups with care home staff provided qualitative data which was thematically analysed.

RESULTS

Staff increased in self-perceived knowledge across the six components of hydration care. 59% of residents had an increase in median fluid intake post intervention. During the time of the intervention, a 13% decrease in UTIs and antibiotic usage to treat UTIs across the 3 care homes was recorded, however falls and hospitalisations increased. Themes arising from focus groups included the role of information for action, accessibility of online training, online training content.

CONCLUSIONS

This study demonstrates that a brief, low cost, online multi-component intervention focused on care home staff can increase the fluid intake of residents. A reduction in UTIs and antibiotic consumption was observed overall. Empowering care home staff could be a way of reducing the burden of infection in this setting.

Fluid intake recommendations in urolithiasis and general advice to patients without metabolic risk factors

Urolithiasis is a highly prevalent global disease with substantially increasing incidence in the last two decades. Data from the literature suggests that 26%-50% of patients will have a recurrence within 10 years after an initial symptomatic stone episode. Therefore, interest has been raised in preventive strategies, aiming to modify the risk factors of stone recurrence by implementing dietary and lifestyle changes and specific medical treatments for stone formers, depending on their recurrence risk factors. Certain dietary factors are thought to contribute significantly to the increased incidence of urolithiasis, particularly a diet low in fiber and high in animal protein, fat, and sodium. Fluid intake is perhaps the most important and modifiable step in the prevention of urolithiasis, irrespective of stone composition. However, the amount of fluid to be consumed and the implications of various fluid types on stone formation are still controversial. In this article, the relationship between fluid intake, beverage types and stone formation-prevention will be discussed. Moreover, general dietary recommendations for patients without metabolic risk factors will be reviewed based on the current literature.

Case-based review of dietary management of cystinuria

PURPOSE

The currently recommended treatment strategy for cystine stone formers is based on a progressive approach that starts with the most conservative measures. In patients with cystinuria, increased patient compliance with dietary management and medical treatment is associated with fewer stone interventions. In this case-based review, the dietary management of cystine stone former was reviewed under the guidance of evidence-based medicine.

METHODS

The dietary management of the 13-year-old cystinuria patient, who underwent 18 endourological stone interventions, was reviewed in the light of evidence-based medicine. A literature search was performed in Pubmed, MEDLINE, Embase, and Cochrane Library databases according to PRISMA guidelines published from 1993 to September 2022. A total of 304 articles were included in this paper.

RESULTS

In managing patients with cystinuria, hyperhydration, and alkalinization of the urine with medical treatment, the rational use of cystine-binding drugs by taking into account individual situations has come to the fore. A limited study has argued that a vegetarian diet is effective as the alkaline load from fruits and vegetables can reduce the amount of alkalizing substances required to achieve urinary alkalinization above pH 7.5, making it particularly suitable for the dietary treatment of cystine stone disease.

CONCLUSION

Life-long follow-up with dietary modification, hyperhydration, and personalized medical therapy (alkalinization and cystine-binding drugs) are critical in preventing chronic kidney disease and kidney failure in cystinuria.

Risk factors associated with heat-related illness among sugarcane farmers in Thailand

Heatstroke is defined as severe symptoms of heat-related illness, which could lead to death. Sugarcane farmers are at high risk of heatstroke under extremely hot outdoor working conditions. We explored the prevalence of heat-related illness symptoms and risk factors related to heat-related illness among sugarcane farmers working in the summer. We conducted a cross-sectional study using questionnaire interviews among 200 sugarcane farmers in Kamphaeng Phet Province, Thailand. The questionnaire addressed demographics, heat-related symptoms experienced during summer at work, and occupational factors. Bioelectrical impedance analysis was used to assess body mass index and body fat percentage. Watson formula equations were used to estimate total body water. The prevalence of heat-related illness symptoms was 48%; symptoms included heavy sweating, weakness/fatigue, dizziness, muscle cramps, headache, and vertigo. Factors associated with heat-related illness included women and clothing. Sugarcane farmers wearing two-layer shirts had a higher risk of heat-related illness. Farmers with fluid intake 3.1-5.0 liters per day had a 79% lower risk of heat-related illness. Our findings demonstrated that sugarcane farmers are at risk of heat-related illness. We confirmed that working conditions, including wearing proper clothing and water-drinking habits, can reduce this risk.

Association of water intake and hydration status with risk of kidney stone formation based on NHANES 2009-2012 cycles

OBJECTIVE

Evaluating the association of water intake and hydration status with nephrolithiasis risk at the population level.

DESIGN

It is a cross-sectional study in which daily total plain water intake and total fluid intake were estimated together with blood osmolality, urine creatinine, urine osmolality, urine flow rate (UFR), free water clearance (FWC) and urine/blood osmolality ratio (U_osm:B_osm). The associations of fluid intake and hydration markers with nephrolithiasis were evaluated using multivariable logistic regression.

SETTING

General US population.

PARTICIPANTS

A total of 8195 adults aged 20 years or older from the National Health and Nutritional Examination Survey 2009-2012 cycles.

RESULTS

The population medians (interquartile ranges, IQR) for daily total plain water intake and total fluid intake were 807 (336-1481) and 2761 (2107-3577) ml/d, respectively. The adjusted OR (95 % CI) of nephrolithiasis for each IQR increase in total plain water intake and total fluid intake were 0·92 (95 % CI 0·79, 1·06) and 0·84 (95 % CI 0·72, 0·97), respectively. The corresponding OR of nephrolithiasis for UFR, blood osmolality, U_osm:B_osm and urine creatinine were 0·87 (95 % CI 0·76, 0·99), 1·18 (95 % CI 1·06, 1·32), 1·38 (95 % CI 1·17, 1·63) and 1·27 (95 % CI 1·11, 1·45), respectively. A linear protective relationship of fluid intake, UFR and FWC with nephrolithiasis risk was observed. Similarly, positive dose-response associations of nephrolithiasis risk with markers of insufficient hydration were identified. Encouraging a daily water intake of >2500 ml/d and maintaining a urine output of 2 l/d was associated with a lower prevalence of nephrolithiasis.

CONCLUSION

This study verified the beneficial role of general water intake recommendations in nephrolithiasis prevention in the general US population.

Restrictive intraoperative fluid intake in liver surgery and postoperative renal function: A propensity score matched study

BACKGROUND

Postoperative acute kidney injury (AKI) is a common complication in hepatic surgery. In hepatic surgery, relative hypovolemia may help to limit blood loss, but the consequences of restrictive fluid intake are unknown. The goal of this study was to determine the influence of intraoperative fluid intake on the incidence of AKI and its consequences.

METHODS

Data from 397 consecutive patients who underwent liver resection were prospectively recorded and retrospectively analyszed. We compared the incidence of postoperative acute kidney failure in patients given restrictive (≤ 5 mL/kg/h) versus liberal (> 5 mL/kg/h) fluid therapy. We calculated a 1:1 match propensity score using logistic regression to estimate the likelihood of patients receiving restrictive or liberal intraoperative fluid intakes. The association between the intraoperative fluid intake strategy and occurrence of postoperative AKI were tested using a Cox frailty model on the database of matched patients.

RESULTS

Postoperative AKI was diagnosed in 133 of the 397 patients. Fluid intake strategy was restrictive for 121 patients and liberal for 276 patients. After propensity score matching to balance confounding factors, the liberal strategy was associated with a significantly lower risk for postoperative AKI compared to the restrictive strategy (Hazard Ratio 0.40 [0.29; 0.56], P<0.001). Patients with postoperative AKI had longer hospital stays and higher mortality. There were no cases of further blood loss in the liberal fluid intake group.

CONCLUSIONS

A restrictive fluid intake strategy is a risk factor for developing postoperative AKI, with serious consequences, without reducing blood loss in liver surgery.

Association between fluid intake and extubation failure in intensive care unit patients with negative fluid balance: a retrospective observational study

BACKGROUND

Negative fluid balance (NFB) is associated with reduced extubation failure. However, whether achieving more NFB can further improve extubation outcome has not been investigated. This study aimed to investigate whether more NFB and restricted fluid intake were associated with extubation success.

METHODS

We performed a retrospective study of adult patients with mechanical ventilation (MV) admitted to Medical Information Mart for Intensive Care (MIMIC-III) from 2001 to 2012. Patients with duration of MV over 24 hours and NFB within 24 hours before extubation were included for analysis. The primary outcome was extubation failure, defined as reintubation within 72 hours after extubation. Association between fluid balance or fluid intake and extubation outcome were investigated with multivariable logistic models.

RESULTS

A total of 3433 extubation events were recorded. 1803 with NFB were included for the final analysis, of which 201(11.1%) were extubation failure. Compared with slight NFB (- 20 to 0 ml/kg), more NFB were not associated improved extubation outcome. Compared with moderate fluid intake (30 to 60 ml/kg), lower (< 30 ml/kg, OR 0.75, 95% CI [0.54, 1.05], p = 0.088) or higher (> 60 ml/kg, OR 1.63, 95% CI [0.73, 3.35], p = 0.206) fluid intake was not associated with extubation outcome. Duration of MV, chronic obstructive pulmonary disease (COPD), hypercapnia, use of diuretics, and SAPSIIscore were associated with extubation failure.

CONCLUSIONS

More NFB or restricted fluid intake were not associated with reduced extubation failure in patients with NFB. However, for COPD patients, restricted fluid intake was associated with extubation success.

Fluids affecting bladder urgency and lower urinary symptoms: results from a randomized controlled trial

INTRODUCTION AND HYPOTHESIS

Caffeinated, alcoholic, artificially sweetened, carbonated, and acidic beverages are pervasive and consumed in large quantities. Reputedly, these beverages are "irritating to the bladder" and result in heightened void frequency, but prior studies lack control for intake volume. We tested the null hypothesis that women recruited from the community who demonstrate overactive bladder symptoms will show no difference by groups in void frequency when one group is instructed to replace listed beverages by substituting non-irritants (emphasis on water or milk) and the other group is instructed in healthy eating.

METHODS

This was a parallel-group randomized controlled trial design with a three-period fixed sequence (baseline and 2 and 6 weeks post-baseline). We recruited 105 community women with overactive bladder symptoms.

INCLUSION CRITERIA

>7 voids per day or 2 voids per night, daily intake of ≥16 oz. (473 ml) of beverages containing the ingredients listed above, and ≥ 32 oz. (946 ml) of total fluid intake. Stratified randomization was conducted. The primary outcome was average daily void frequency on a 3-day diary.

RESULTS

Participants were 86% white, mean (SD) age was 46.6 (17.6) years, and baseline void frequency was 9.2 (2.9) voids per day. At 2 and 6 weeks, estimated average (SD) difference in void frequency between group 1 and group 2 was -0.46 (0.57) and -0.31 (0.57) voids per day (p > 0.05); the null hypothesis was not rejected.

CONCLUSIONS

Women who reduce potentially irritating beverages while maintaining total fluid volume intake is not predictive of void frequency. Further research on type and volume of beverage intake is recommended.

Urge suppression and modified fluid consumption in the management of female overactive bladder symptoms

Background:

At the initial management of overactive bladder (OAB) syndrome urge suppression technique along with other behavioural modification could be a good option.

Methods:

Prospective experimental study conducted between 2015 and 2019. Women complaining of OAB were enrolled. Three-day bladder diary and patient global impression of severity (PGI-S) scale were evaluated at baseline. Then, the women were asked to perform the urge suppression technique whenever urgency occurred. She stopped moving, sat down and started squeezing the pelvic floor muscle quickly and tightly about ten times without full relaxation in between squeezes. After that, she did something to distract her mind. Once urgency disappeared, she proceeded to the toilet. If urgency reappeared, she stopped moving and repeated the same thing. Only on relax mood she entered toilet. Modified fluid consumption was - total daily requirement divided into three parts and two-third of that was taken from morning to lunch. The remaining one-third was divided again in three parts and two-third of that was taken before evening. Rest few amount was taken from the evening till waking up the next morning. After 3 months, 3-day bladder diary and patient global impression of improvement (PGI-I) scale assessed the improvement.

Results:

Ninety-one women ultimately completed the study. Frequency and nocturia were reduced. Seventy-six women had improvement of their urgency sensation (P < 0.001), whereas urgency urinary incontinence reduction was statistically not significant (P > 0.05). PGI-I scale showed that 51.6% felt that either they were very much better or much better.

Conclusion:

Urge suppression and modified fluid consumption is good adjunct in female OAB management.

Audit of the appropriateness and accuracy of fluid intake and output monitoring: experience in a tertiary hospital

BACKGROUND

The current practice of fluid intake and output monitoring for hospitalised patients in one local acute care tertiary hospital was unclear and inconsistent. Inaccurate fluid balance monitoring and poor documentation can result in poor clinical outcomes.

AIM

To provide an overview of the current practice of ordering, monitoring and documentation of patient fluid intake and output during hospitalisation.

METHODS

Electronic charts of 2199 adults were reviewed for appropriateness and accuracy of monitoring and documentation of the fluid balance records. Data retrieved for each patient included: (1) Was daily fluid balance monitoring clinically indicated? (2) Was daily fluid balance monitoring prescribed by the doctors or initiated by the nurses? (3) Was the daily fluid balance documentation accurate for the entire admission?

FINDINGS

Of the reviewed patients, 68% were on fluid balance monitoring, of whom 31% were prescribed by medical teams and 69% were nurse-initiated. Among patients who were receiving fluid balance monitoring, 78% were clinically indicated (35% prescribed by doctors), and 22% had no clinical indications (18% prescribed by doctors). Overall, documentation accuracy of the intake and output charts was 77%, with 100% accuracy in the oral and intravenous fluid intake, and 21% accuracy in the output documentation. Among the inaccurate documentation of monitoring with no quantifiable amount, 'void in toilet' was the most inaccurately documented (93.3%).

CONCLUSIONS

It is vital to address the current disparities in hospital practice, which include prescribing fluid balance monitoring for patients without a clinical indication and documenting incomplete or poor quality information in patients' intake and output charts. Future quality improvement and research work is needed to improve patient safety and outcomes.

Predicted sweat rates for group water planning in sport: accuracy and application

This study tested the accuracy of a novel, limited-availability web application (H₂Q™) for predicting sweat rates in a variety of sports using estimates of energy expenditure and air temperature only. The application of predictions for group water planning was investigated for soccer match play. Fourteen open literature studies were identified where group sweat rates were reported (n = 20 group means comprising 230 individual observations from 179 athletes) with fidelity. Sports represented included: walking, cycling, swimming, and soccer match play. The accuracy of H₂Q™ sweat rates was tested by comparing to measured group sweat rates using the concordance correlation coefficient (CCC) with 95% confidence interval [CI]. The relative absolute error (RAE) with 95% [CI] was also assessed, whereby the mean absolute error was expressed relative to an acceptance limit of 0.250 L/h. The CCC was 0.98 [0.95, 0.99] and the RAE was 0.449 [0.279, 0.620], indicating that the prediction error was on average 0.112 L/h. The RAE was < 1.0 for 19/20 observations (95%). Drink volumes modeled as a proxy for sweat losses during soccer match play prevented dehydration (< 1% loss of body mass). The H₂Q™ web application demonstrated high group sweat prediction accuracy for the variety of sports activities tested. Water planning for soccer match play suggests the feasibility of easily and accurately predicting sweat rates to plan group water needs and promote optimal hydration in training and/or competition.

Barriers to Accurate Fluid Measurement in Perioperative Patients: A Mixed Methods Approach

BACKGROUND

Surgeons depend on fluid intake and output (I/O) measurements for assessment of resuscitation and fluid balance during the perioperative period. Frequently, these measurements are taken by Registered Nurses (RNs) and/or Patient Care Technicians (PCTs). There is variability in the accuracy and consistency of these measurements across nursing units. The goal of this study is to establish what barriers exist in obtaining accurate fluid measurements and potential solutions.

MATERIALS AND METHODS

A mixed-method, sequential study design was utilized. First, a survey was conducted at a tertiary care institution of 8 nonintensive care nursing units assessing the perceptions of RNs (n = 85) and PCTs (n = 38) regarding fluid intake and output measurements for surgical patients. Four focus groups were then conducted to expand upon the results of the survey. Fourteen participants (10 RNs and 4 PCTs) were interviewed, and transcripts were analyzed by three reviewers. Qualitative data were manually coded by reviewers using a hierarchical methodology.

RESULTS

Survey response rate was 40.6%. The strongest barriers in the survey were patient load and staff time limitations. About half (49%) of the respondents acknowledged that fluid measurements were inaccurate half of the time. PCTs spend more time collecting and charting I/Os and have higher patient loads (P < 0.001) than RNs. PCTs noted more difficulty with complex patients (P = 0.017) and devices for outputs (P = 0.004). PCT's (94%) handwrite data prior to electronic entry. One-third of nurses reported direct electronic entry (P < 0.001). Overall, 71% would prefer to chart in patient's rooms. Most (80%) of respondents received <5 h of fluids-related training at the time they were hired. Cronbach's alpha for three focus group reviewers was 0.84 (95% CI 0.693-0.923). Themes included understaffing, lack of training, a high percentage of traveling nurses, and poor communication regarding new orders. Recommended solutions to improve I/Os included in-room kiosks for electronic entry and relief of staffing burdens.

CONCLUSIONS

Fluid I/O measurement accuracy and efficiency may be improved by increased staffing, educational programs, and computer access, streamlining of order sets, simplicity of EMR data entry, and a standardized process for measuring, recording, and charting I/Os.

Mineral preference in rats treated with muscimol into the lateral parabrachial nucleus

Injection of muscimol, a GABA_A receptor agonist, into the lateral parabrachial nucleus (LPBN) induces 0.3 M NaCl intake in rats. In the present work, we investigated whether such an effect applies to hypertonic (0.3 M) mineral solutions in general or is selective to sodium solutions in a 240 min intake test. Muscimol injection (0.5 nmol/0.2 μL) compared to vehicle injection into the LPBN of adult hydrated rats produced a preferential ingestion of 0.3 M NaCl (25.3 ± 10.2 mL) followed by a 0.3 M NaHCO₃ intake (11.7 ± 5.6 mL), with no significant effect on water, KCl and CaCl₂ intake. Only the effect of muscimol on NaCl intake (19.0 ± 10.4 mL) persisted in cell-dehydrated rats, with hardly any effect on water or other mineral solutions. The results suggest that the LPBN controls the ingestion of hypertonic NaCl and NaHCO₃. They also suggest a selective mechanisms involving the LPBN to check hypertonic sodium intake.

Risk factor analysis of insufficient fluid intake among urban adults in Wuxi, China: a classification and regression tree analysis

Background

Dehydration due to insufficient fluid intake (IFI) is detrimental to health. This cross-sectional study aimed to assess the fluid intake of urban adults in Wuxi, China, and to identify potential risk factors contributing to IFI.

Methods

Adults were selected from the urban area of Wuxi, China, using a multiple-stage random sampling method. The fluid intake information was obtained with a 24-h self-reported diary over seven consecutive days in both summer and winter of 2015. A classification and regression tree (CART) analysis was conducted to detect the potential risk factors associated with IFI. CART is a machine-learning algorithm that portions the data into subsets by threshold.

Results

A total of 584 adults aged 18–87 years were included. The results showed that the median (P25–P75) values of daily fluid intake of the participants were 1100 (800–1550) mL in summer and 1000 (750–1300) mL in winter. Women had a higher prevalence of IFI than men in both summer (odds ratio (OR) = 2.683, 95% confidence interval (CI): 1.830–3.934) and winter (OR = 2.636, 95% CI: 1.677–4.142). The results of CART analysis showed that, in summer, BMI < 25 kg/m² (probability: 64.2%) and age < 64 years (probability: 67.4%) were main risk factors of IFI for men, and BMI < 29 kg/m² (probability: 81.6%) and living in C Community (probability: 86.7%) were main risk factors for women. In winter, age < 40 years (probability: 81.8%) and BMI < 20 kg/m² (probability: 94.5%) were identified as main risk factors of IFI for men and women, respectively.

Conclusions

Most of the participants living in the study site had IFI. The fluid consumption varied by gender, age, location, and BMI. The findings could be useful for the implementation and optimization of intervention programs by identifying the individuals who may at greater risk of dehydration.

Fluid intake-related association between urine output and mortality in acute respiratory distress syndrome

Background

Acute respiratory distress syndrome (ARDS), a complex response to various insults, has a high mortality rate. As pulmonary edema resulting from increased vascular permeability is a hallmark of ARDS, management of the fluid status, including the urine output (UO) and fluid intake (FI), is essential. However, the relationships between UO, FI, and mortality in ARDS remain unclear. This retrospective study aimed to investigate the interactive associations among UO, FI, and mortality in ARDS.

Methods

This was a secondary analysis of a prospective randomized controlled trial performed at 10 centers within the ARDS Network of the National Heart, Lung, and Blood Institute research network. The total UO and FI volumes within the 24-h period preceding the trial, the UO to FI ratio (UO/FI), demographic data, biochemical measurements, and other variables from 835 patients with ARDS, 539 survivors, and 296 non-survivors, were analyzed. The associations among UO, FI, the UO/FI, and mortality were assessed using a multivariable logistic regression.

Results

In all 835 patients, an increased UO was significantly associated with decreased mortality when used as a continuous variable (odds ratio [OR]: 0.98, 95% confidence interval [CI]: 0.98–0.99, P = 0.002) and as a quartile variable (OR of Q2 to Q4: 0.69–0.46, with Q1 as reference). To explore the interaction between UO and FI, the UO/FI was calculated, and a cut-off value of 0.5 was detected for the association with mortality. For patients with a UO/FI ≤0.5, an increased UO/FI was significantly associated with decreased mortality (OR: 0.09, 95% CI: 0.03–0.253, P <  0.001); this association was not significant for patients with UO/FI ratios > 0.5 (OR: 1.04, 95% CI: 0.96–1.14, P = 0.281). A significant interaction was observed between UO and the UO/FI. The association between UO and mortality was significant in the subgroup with a UO/FI ≤0.5 (OR: 0.97, 95% CI: 0.96–0.99, P = 0.006), but not in the subgroup with a UO/FI > 0.5.

Conclusions

The association between UO and mortality was mediated by the UO/FI status, as only patients with low UO/FI ratios benefitted from a higher UO.

[Influence of Critical Care Ultrasound Oriented Fluid Management in Different Stages of Shock to the Outcome]

OBJECTIVE

To investigate the relationship between fluid management oriented by critical care ultrasound and prognosis in patients with shock.

METHODS

We analyzed the data of a randomized controlled trial called Critical Care Ultrasound Oriented Shock Treatment (CCUSOST) in the Department of Critical Care Medicine, West China Hospital retrospectively. 77 patients in the critical care ultrasound oriented treatment group (experimental group) and 70 patients in the conventionally treated group as control were included in the statistics, to evaluate the relationship between fluid intake and prognosis. Univariate and multivariate logistic regression analyses were used to analyze risk factors for ICU mortality.

RESULTS

The baseline indexes of the patients in the experimental group and the control group were consistent. The ICU mortality of the experimental group was significantly lower than that of the control group (P < 0.05).The fluid intake in the stabilization and de-escalation phases was less than the the control group (P < 0.05). We divided these shock patients into survival group (92 cases) and non-survival (55 cases) according to whether they died in ICU, and the univariate analysis for ICU mortality showed that acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, SOFA score, Lac, hourly urine output, total fluid intake, fluid intake in the salvage and optimization stages, fluid intake in the stabilization and de-escalation stages were significantly different (P < 0.05) between survivers and non-survivers. Multivariete analysis showed that the fluid intake during the salvage and optimization phases, fluid intake in the stabilization and de-escalation phases were independent risk factors for ICU mortality.

CONCLUSION

Critical care ultrasound oriented shock fluid management could reduce fluid intake of stabilization and de-escalation phases, and improved adverse outcome; whether the fluid intake during stabilization and de-escalation phases, or the fluid intake during the salvage and optimization phases, both were associated with patient prognosis.

Beverage consumption and energy intake among Canadians: analyses of 2004 and 2015 national dietary intake data

Background

Among adults and children consuming Western diets, beverages are significant sources of free sugars, saturated fats, excess calories, and alcohol, with relevance to chronic disease risk. The impact of recent healthy eating policies and beverage market evolutions on population-level consumption patterns in Canada is unknown. The current study examined trends in intake of a range of beverage types among a nationally-representative sample of Canadians, with stratification by socio-demographic characteristics.

Methods

The 2004 (n = 34,775) and 2015 (n = 20,176) nutrition-focused cycles of the Canadian Community Health Surveys are cross-sectional surveys representative of the population of the 10 Canadian provinces. Based on a single multiple-pass 24-h dietary recall for each participant, fluids consumed as beverages were grouped into seven categories. Using linear regression, reported intake (volume, ml and energy, kcal) of each category was characterized over time and in relation to sex, age, ethnicity, income, body mass index (BMI), and province of residence.

Results

In 2015, Canadians reported consuming an average of 1806 ml (275 kcal) fluids as beverages per day, including: plain water 867 ml (0 kcal); other unsweetened beverages, e.g. coffee, 364 ml (6 kcal); sugar-sweetened beverages (SSBs) 204 ml (99 kcal); plain milk 132 ml (64 kcal); alcoholic drinks 120 ml (71 kcal); 100% juice 74 ml (34 kcal); and diet or low calorie beverages 44 ml (2 kcal). Differential consumption was observed across socio-demographic groups, with high consumption of sugary drinks (i.e., SSBs and 100% juice) and alcohol across groups. From 2004 to 2015, the reported volumes of beverages consumed decreased by 10% (energy: − 24%). With adjustment for socio-demographic characteristics, there were significant changes (p < 0.001) over time in intake of: 100% juice − 40% (− 38%); plain milk − 37% (− 35%); SSBs − 26% (− 20%); diet or low calorie beverages (− 46%); and other unsweetened beverages − 11% (− 42%). The volume of plain water consumed increased by 10% (p < 0.0001). Intake of alcoholic (volume and energy) and diet or light beverages did not change significantly.

Conclusions

Lower intake of beverages was reported by Canadians in 2015 versus 2004, with a shift towards plain water. Consumption of sugary drinks decreased, but these beverages continue to contribute substantially to Canadians' overall energy intake. The findings underscore the need for policies to further reduce the consumption of sugary and alcoholic beverages, as well as calories from beverages.

Increased fluid intake for the prevention of urinary tract infection in adults and children in all settings: a systematic review

BACKGROUND

Non-antibiotic interventions for urinary tract infection (UTI) prevention have been investigated as a strategy to reduce antibiotic prescribing for UTI and subsequent antibiotic resistance. Increased hydration is widely advocated for preventing UTI; however, evidence for its effectiveness is unknown.

AIM

To systematically review the published literature on the effectiveness of increased fluid intake as a preventive intervention for UTI in adults and children in any setting.

METHODS

Five electronic databases were searched from inception to February 2019 to identify published randomized controlled trials (RCTs) and quasi-experimental studies evaluating the effectiveness of high (≥1.5 L/24 h) versus normal/low (<1.5 L/24 h) fluid intake for UTI prevention. The outcome was UTI incidence. Risk of bias was assessed using the Cochrane Collaboration's tool. Due to the small number of studies identified, meta-analysis was not possible. Hence a narrative synthesis was undertaken.

FINDINGS

Of the 2822 potentially relevant papers, two were eligible for inclusion: an RCT (individual randomization) and a cluster-RCT. Both studies differed regarding participants, setting, sample size, UTI definition, and intervention. The RCT was assessed as having a low risk of bias whereas the cluster-RCT had a high risk of bias. Only the RCT, which included healthy premenopausal women visiting primary care clinics, demonstrated statistical significance for the effect of high fluid intake for UTI prevention.

CONCLUSION

The lack of enough adequately powered and robust RCTs highlights the need for further research on the effectiveness of this intervention for UTI prevention.

Fluid and total water intake in a senior mediterranean population at high cardiovascular risk: demographic and lifestyle determinants in the PREDIMED-Plus study

PURPOSE

We aimed to evaluate associations between compliance with recommendations for total water intake (TWI) and total water intake from fluids (TWIF), and some socio-demographic and lifestyle factors of a senior Mediterranean population at high cardiovascular risk.

METHODS

Cross-sectional analysis with data of 1902 participants from the PREDIMED-Plus study. A validated 32-item Spanish fluid-intake questionnaire was used to assess beverage consumption and water intake. Multivariable logistic regression models were used to assess the odds ratio (OR) and the 95% confidence interval (CI) for complying with European Food Safety Agency recommendations for TWI and TWIF according to various socio-demographic and lifestyle factors, and for the joint associations of Mediterranean diet (MedDiet) adherence and moderate-vigorous physical activity (MVPA).

RESULTS

The mean total volume of fluid intake in the population studied was 1934 ± 617 mL/day. Water was the most frequently consumed beverage. Significant differences between sex were only observed in alcoholic and hot beverage consumption. Compliance with TWIF was associated with being women (OR 3.02; 2.40, 3.80), high adherence to MedDiet (OR 1.07; 1.02, 1.12), and participants who were more engaged in physical activity (PA) (OR 1.07; 1.02, 1.13). Age was inversely associated (OR 0.96; 0.94, 0.98). Similar results for TWI recommendations compliance were observed in relation to being women (OR 5.34; 3.85, 7.42), adherence to MedDiet (OR 1.16; 1.02, 1.31) and PA (OR 1.07; 1.00, 1.15). The joint association of PA and MedDiet, showed that participants with higher adherence to MedDiet and meeting WHO recommendations for MVPA complied better with the TWI recommendations (OR 1.66; 1.19, 2.32).

CONCLUSIONS

High compliance with recommendations for TWI was associated with being a woman, and a healthy lifestyle characterized by high adherence to the MedDiet and PA.

Examining the links between hydration knowledge, attitudes and behavior

PURPOSE

This study aimed to examine the psychological factors (knowledge, barriers and facilitators) that can contribute to hydration-related behaviors (i.e., fluid intake) in the general population and how these relate to physical health.

METHODS

A structured survey was developed to examine the links between hydration knowledge (29 items), attitudes about hydration (80 items), and fluid intake behavior (8 items) among US adults. Survey data from Phase 1 (n =301, US adults) psychometrically evaluated the items via item analysis (knowledge and fluid behavior) and factor analysis (attitudes). Phase 2 survey data (n =389, US adults and college students) refined and validated the new 16-item hydration knowledge measure, 4-item fluid intake behavior index, and 18-item attitude measure (barriers and facilitators of hydration-related behaviors) alongside indices of physical health (BMI and exercise behaviors).

RESULTS

Participants had a moderate level of hydration knowledge (Phase 1: 10.91 ± 3.10; Phase 2: 10.87 ± 2.47). A five-factor measure of attitudes which assessed both facilitators (social pressure and attention to monitoring) and barriers (lack of effort, physical barriers and lack of a fluid container) to hydration demonstrated strong internal consistency (αs from 0.75 to 0.90). Attitudes about hydration-most notably barriers to hydration-were associated with indicators of health and with fluid intake behaviors, whereas hydration knowledge was not.

CONCLUSIONS

Increasing hydration knowledge may be necessary for people who hold inaccurate information about hydration, but attitudes about hydration are likely to have a larger impact on fluid intake behaviors and health-related outcomes.

Fluid and energy intake in stroke patients during acute hospitalization in a stroke unit

Proper hydration and nutrition have been found to be contributing factors to a better recovery in patients after stroke. A better knowledge of factors influencing fluid and energy intake may contribute to a better care of the acute stroke patient. Aim of this study was to describe hydration status, fluid intake, and energy intake of stroke patients during acute hospitalization in a stroke unit. A retrospective descriptive study was conducted in stroke patients admitted to a stroke unit. All patients received neurological evaluation and urinary osmolality (uOsm) measure at admission and discharge. During stroke unit stay patients received a day-by-day diary to record data about beverages, food, and therapy. Water and energy content were then reported based on a national nutritional database. Ninety-five patients were included in the analysis. uOsm did not differ between patients with or without dysphagia, with uOsm > 500 mosm/kg in 58.1% at admission and 57.8% at discharge. Inadequate fluid intake was found in 41.2% of the sample with no difference between groups. Insufficient energy intake was found in 95.6% of the sample, with no patients with dysphagia reaching the minimum suggested amount. Our results suggest that a relevant proportion of stroke patients with and without dysphagia may not improve their hydration status during the first days after admission. Diet and therapy were insufficient to achieve recommended fluid intake and energy intake in a large proportion of patients, suggesting a more careful monitoring of hydration and nutrition needs.

Drinking vessel preferences in older nursing home residents: optimal design and potential for increasing fluid intake

BACKGROUND:

residents in nursing and residential care homes are at risk of dehydration due to both resident and institutional factors. Previous studies have focused on improving fluid intakes by concentrating on types of fluids offered and assisting residents to drink.

AIM:

to determine resident opinion of the optimal features of drinking vessels and evaluate the impact of improving vessel design on fluid consumption.

METHODS:

residents from two units (25-bed and 21-bed) in one nursing home evaluated a range of drinking vessels. Vessels with preferred features were introduced on a 25-bed unit. The effect was tested by observing residents' fluid consumption during breakfast on three consecutive days and comparing with baseline intakes.

FINDINGS:

vessels that received the highest ratings were lightweight, had large handles and held 200-300 ml of fluid. Following the introduction of the new drinking vessels, mean fluid intakes at breakfast increased from 139 ml (±84 ml) to 205 ml (±12 ml, n=65), p=0.003.

CONCLUSION:

some drinking vessels used in nursing homes may be difficult for residents to handle. Making improvements to the design of drinking vessels has the potential to increase fluid intakes without increasing staff workload.

Public knowledge of dehydration and fluid intake practices: variation by participants' characteristics

Background

Dehydration results from a decrease in total body water content either due to less intake or more fluid loss. Common symptoms of dehydration are dry mouth/tongue, thirst, headache, and lethargy. The aim of this study was to assess knowledge of dehydration definition, symptoms, causes, prevention, water intake recommendations and water intake practices among people living in Riyadh, Saudi Arabia.

Methods

A cross-sectional study using self-reported questionnaire was employed. Participants were invited during their visit to shopping malls. The shopping malls were selected based on geographical location covering east, west, north and southern part of the city. Self-filled questionnaires were distributed to 393 participants, using systematic sampling technique. Variables recorded included demographics, past medical history, knowledge of dehydration definition, symptoms, causes, prevention and daily water intake practices. Descriptive statistics were summarised as mean, standard deviation and proportions. Negative binomial model was used to identify the predictors of water intake. Analyses were performed using SAS version 9.4 (SAS Institute, Cary, NC, USA).

Results

Out of 393 participants, 273(70%) were Saudi, 209(53%) were female, average age was 32.32 ± 8.78 years. Majority 366(93%) had good knowledge of dehydration definition, 332(84%) for dehydration prevention, and 293(74%) of water intake recommendation. Top three recognized dehydration symptoms were: dry lips (87%), thirst (84%), dry tongue (76%) and recognized dehydration causes were: diarrhoea (81%), sweating (68%) and vomiting (62%). The less recognized symptoms were fatigue 176(44.78%), lack of focus 171(43.5%), headache/dizziness 160(40.71%), light headedness 117(29.7%), muscle weakness 98(24.94%), rapid breathing 90(22.9%), and muscle cramps 64(16.28%).The participants had reported an average of 5.39 ± 3.32 water glasses intake per day. The total volume of water intake was significantly different between males n = 184 (3.935 ± 2.10 l) and females n = 209 (3.461 ± 2.59 l) (p = 0.046). The participants’ weight status, intake of juice or tea were the significant predictors of more water intake.

Conclusion

The participants displayed good knowledge of dehydration definition, prevention, and water intake recommendation. The participants also displayed good knowledge of the common symptoms, however knowledge was lacking for uncommon symptoms. Moreover, participants had reported adequate water intake, meeting the daily water intake recommendation of ≥3.7 l for men and ≥ 2.7 l for women.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-6252-5) contains supplementary material, which is available to authorized users.

Water intake and hydration state in children

PURPOSE

Although low water intake has been associated with adverse health outcomes, available literature indicated that the majority of children do not meet the water intake guidelines and they are underhydrated based on elevated hydration biomarkers. This review examined the water intake habits and hydration status in children from 32 observational studies (n = 36813).

METHODS

PubMed, Web of Science, and CINAHL were used to identify relevant articles. Total water/fluid intake from 25 countries was compared with water intake recommendations and underhydration (urine osmolality greater than 800 mmol kg^-1) was assessed. Risk of bias was assessed using customized categories following the review guideline for observational studies.

RESULTS

From 32 studies, only 11 studies reported both water intake and hydration status. 12 out of 24 studies reported mean/median water/fluid intake below the guidelines, while 4 out of 13 studies that assessed hydration status indicated underhydration based on urine osmolality (greater than 800 mmol kg^-1). Among the 19 countries that reported comparison of water/fluid intake with guidelines, 60 ± 24% of children (range 10-98%) failed to meet them.

CONCLUSION

These findings suggest that children are not consuming enough water to be adequately hydrated.

Prevalence and Risk Factors Associated With Low Fluid Intake in Institutionalized Older Residents

OBJECTIVE

The aim of this study was to determine the prevalence of low fluid intake in institutionalized older residents and the associated factors.

DESIGN

This was a cross-sectional study.

SETTING AND PARTICIPANTS

The study was carried out at a nursing home with a capacity for 156 residents, all of whom were older than 65 years.

MEASURES

Data were collected on the fluids consumed by each resident over a period of 1 week. Information relating to sociodemographic variables and to residents' health, nutrition, and hydration status was also collected.

RESULTS

Of 53 residents, 34% ingested less than 1500 mL/d. The factors with the greatest correlation associated with low fluid intake were cognitive and functional impairment, the risk of suffering pressure ulcers, being undernourished, a texture-modified diet, dysphagia, impaired swallowing safety, and BUN:creatinine ratio.

CONCLUSIONS/IMPLICATIONS

The results obtained highlight the scale of low fluid intake in nursing homes and also aid to identify and understand the factors associated with this problem. The findings could help us to develop specific strategies to promote the intake of liquids and thereby reduce the incidence of dehydration in nursing homes.

Total Fluid Intake and the Risk of Recurrence in Patients With Non-Muscle Invasive Bladder Cancer: A Prospective Cohort Study

Objectives:

To investigate the role of fluid intake from beverages before and after a diagnosis of bladder cancer in relation to the risk of developing bladder cancer recurrence.

Study Design:

Prospective cohort study.

Methods:

716 patients with non-muscle invasive bladder cancer (NMIBC), who received transurethral resection of a primary bladder tumour (TURBT) and completed self-administrated questionnaires on usual fluid intake from beverages at time of diagnosis (over the year before diagnosis) and during follow-up (over the year after diagnosis), were included. Multivariable Cox regression was used to calculate hazard ratios and 95% confidence intervals of developing recurrent bladder cancer in relation to the intake of total fluid, total alcohol, and individual beverages.

Results:

During 2,025 person-years of follow-up, 238 (33%) of the included 716 NMIBC patients developed one or more recurrences of bladder cancer. Total fluid intake before diagnosis was not associated with a first recurrence of bladder cancer when comparing the highest and lowest intake group (HR = 0.98, 95% C.I. 0.70–1.38, p = 0.91). Comparable results were obtained for total fluid intake pre-diagnosis and the risk of developing multiple recurrences of bladder cancer (HR = 1.01, 95% C.I. 0.87–1.19, p = 0.85). A total of 379 of the 716 patients reported on usual fluid intake within 1 year of diagnosis. No significant associations between total fluid intake 1 year after diagnosis and a first recurrence of bladder cancer were found when comparing the highest and lowest intake group (HR = 0.91; 95% C.I. 0.60–1.37, p = 0.65) or with multiple recurrences of bladder cancer (HR = 1.06; 95% C.I. 0.89–1.26, p = 0.54). In addition, total alcohol intake and individual beverages were not associated with bladder cancer recurrence.

Conclusions:

The results indicate that an individual’s fluid intake from beverages is unlikely to have an important role in bladder cancer recurrence.

Prevention of Cystitis: Travelling between the Imaginary and Reality

As a preventive strategy, increased water intake is often recommended to women affected by recurrent cystitis; however, clinical data are sparse and conflicting. This review evaluates the preventive approaches used as alternatives to obtain relief from the burden of cystitis and focuses on the effect of fluid intake on urinary tract infection.

Fluid intake of children, adolescents and adults in Indonesia: results of the 2016 Liq.In7 national cross-sectional survey

PURPOSE

To report daily total fluid intake (TFI) and fluid types in Indonesia according to age, sex, socio-economic status (SES) and geographic region, and compare TFI with the Indonesian adequate fluid intake (AI) recommendations.

METHODS

Data were collected in 32 cities over nine regions from children (4-9 years, n = 388), adolescents, (10-17 years, n = 478) and adults (18-65 years, n = 2778) using a fluid intake 7-day record (Liq.In⁷); socio-economic status was also recorded. The 7-day mean TFIs were compared with the AI of water set by the Ministry of Health of the Republic of Indonesia.

RESULTS

Total median fluid intakes for all age groups exceeded 2000 mL/day. At population level, TFI was associated with household income (P < 0.001), education (P < 0.001) and Indonesian geographical regions (P < 0.001). More than 67% of participants met the AI of water from fluids. A higher percentage of children and adolescents met the AI (78 and 80%, respectively), compared with adults (72%). Drinking water was the main contributor to TFI in all age groups (76-81%). Sugar-sweetened beverages (SSB) were consumed by 62% children, 72% adolescents and 61% of adults. An SSB intake ≥ 1 serving per day was observed for 24% children, 41% adolescents and 33% adults.

CONCLUSIONS

A high percentage of the population drank enough to meet the AI of water from fluids. Water was the most frequently consumed drink; however, many participants consumed at least one serving of SSB per day. This study provides data to help direct targeted intervention programs.

Challenges in the assessment of total fluid intake in children and adolescents: a discussion paper

Purpose

In recent years, evidence has emerged about the importance of healthy fluid intake in children for physical and mental performance and health, and in the prevention of obesity. Accurate data on water intake are needed to inform researchers and policymakers and for setting dietary reference values. However, to date, there are few published data on fluid or water intakes in children. This is due partly to the fact that drinking water is not always reported in dietary surveys. The aim of this paper is to review the current status of the literature and highlight the challenges of assessing total fluid intake in children and adolescents.

Results

From the dietary assessment literature it is apparent that children present unique challenges to assessing intake due to ongoing cognitive capacity development, limited literacy skills, difficulties in estimating portion sizes and multiple caregivers during any 1 day making it difficult to track intakes. As such, many issues should be considered when assessing total fluid intakes in children or adolescents. Various methods to assess fluid intakes exist, each with its own strengths and weaknesses; the ultimate choice of method depends on the research question and resources available. Based on the literature review, it is apparent that if the research focus is to assess only fluid intake, a fluid-specific method, such as a diary or record, appears to be a feasible approach to provide an accurate estimate of intakes.

Fluid intake of Latin American children and adolescents: results of four 2016 LIQ.IN 7 National Cross-Sectional Surveys

PURPOSE

The primary aim of this survey was to report total fluid intake (TFI) and different fluid types for children (4-9 years) and adolescents (10-17 years) in Mexico, Brazil, Argentina and Uruguay. The second aim was to compare TFI with the adequate intake (AI) of water from fluids as recommended by the USA Institute of Medicine.

METHODS

Data were collected using a validated liquid intake 7-day record (Liq.In 7 ). Participants' characteristics, including age, sex and anthropometric measurements were recorded.

RESULTS

A total of 733 children and 933 adolescents were recruited. Over 75% of children in Uruguay met the IOM's recommended intake. Fewer children in Argentina (64-72%) and Brazil (41-50%) obtained AI and the lowest values were recorded in Mexico (33-44%), where 16% of boys and 14% girls drank 50% or less of the AI. More adolescents in Argentina (42%) met the AIs than other countries; the lowest was in Mexico (28%). Children and adolescents in Mexico and Argentina drank more sugar sweetened beverages than water.

CONCLUSIONS

Large numbers of children and adolescents did not meet AI recommendations for TFI, raising concerns about their hydration status and potential effects on mental and physical well-being. Given the negative effects on children's health, the levels of SSB consumption are worrying.

Fluid intake patterns of children and adolescents: results of six Liq.In7 national cross-sectional surveys

PURPOSE

This study aimed to identify and characterize patterns of fluid intake in children and adolescents from six countries: Argentina, Brazil, China, Indonesia, Mexico and Uruguay.

METHODS

Data on fluid intake volume and type amongst children (4-9 years; N = 1400) and adolescents (10-17 years; N = 1781) were collected using the validated 7-day fluid-specific record (Liq.In7 record). To identify relatively distinct clusters of subjects based on eight fluid types (water, milk and its derivatives, hot beverages, sugar-sweetened beverages (SSB), 100% fruit juices, artificial/non-nutritive sweetened beverages, alcoholic beverages, other beverages), a cluster analysis (partitioning around k-medoids algorithm) was used. Clusters were then characterized according to their socio-demographics and lifestyle indicators.

RESULTS

The six interpretable clusters identified were: low drinkers-SSB (n 523), low drinkers-water and milk (n 615), medium mixed drinkers (n 914), high drinkers-SSB (n 513), high drinkers-water (n 352) and very high drinkers-water (n 264). Country of residence was the dominant characteristic, followed by socioeconomic level, in all six patterns.

CONCLUSIONS

This analysis showed that consumption of water and SSB were the primary drivers of the clusters. In addition to country, socio-demographic and lifestyle factors played a role in determining the characteristics of each cluster. This information highlights the need to target interventions in particular populations aimed at changing fluid intake behavior and improving health in children and adolescents.

Fluid intake of Latin American adults: results of four 2016 Liq.In7 national cross-sectional surveys

Purpose

To report total fluid intake (TFI) and the intake of different fluid types in adults (≥ 18 years old) from Mexico, Argentina, Brazil and Uruguay. To compare intakes between countries and with recommended adequate intake (AI) of water from fluids.

Methods

Cross-sectional data were collected using a validated liquid intake 7-day record (Liq.In⁷) in populations from Argentina (n = 1089), Brazil (n = 477), Mexico (n = 1677) and Uruguay (n = 554). Population characteristics, including age, gender, body mass index and socioeconomic level were recorded. Mean TFI was compared with the AI of water from fluids set by the USA Institute of Medicine.

Results

The lowest TFI was recorded in Mexican women (1748 mL/day) and the highest in Argentinean men (2318 mL/day). Median daily TFI was significantly different between countries; Uruguay and Argentina had higher values than Mexico and Brazil. In the former, plain water contributed to only 25% of TFI, the remainder being predominantly from hot beverages. Approximately, a third of adults did not drink enough fluid to meet the recommended AI. High SSB consumption was reported, which was significantly different between countries (p < 0.05), the highest being in Mexico (median 25–75th percentiles): 531 (300–895 mL/day.

Conclusions

This survey highlights the need to increase water consumption and reduce SSB intake in this region to avoid potential associated health risks. These findings may be useful information in monitoring public health policy strategies.

Electronic supplementary material

The online version of this article (10.1007/s00394-018-1724-z) contains supplementary material, which is available to authorized users.

A comparison of drinking behavior using a harmonized methodology (Liq.In 7 ) in six countries

PURPOSE

To assess drinking occasions (volume and type) according to consumption with food in or outside meals, and location, for six countries.

METHODS

A total of 10,521 participants aged 4-65 years from Argentina, Brazil, China, Indonesia, Mexico and Uruguay completed a validated 7-day fluid intake record. For each drinking event, the volume consumed, the fluid type, the location of intake, and whether the drink was accompanied by food (meal or snack) or not, was recorded.

RESULTS

Similar drinking behaviors were found in Mexico and Argentina; fluid intake during meals was 48 and 45% of total fluid intake (TFI), respectively. In Brazil (55%), Indonesia (58%) and China (66%) most fluid was consumed without food. In Uruguay, 34% of TFI was with a main meal, 31% with food between meals and 35% without food. Indonesia had the highest median (25-75th percentile) TFI; 2520 (1750-3347) mL/day, and China the lowest 1138 (818-3347) mL/day. Water was consumed with meals for 37% of Chinese and 87% of Indonesian participants, while the four Latin-American American countries showed a preference for sweet drinks; 54% in Mexico, 67% in Brazil, 55% in Argentina and 59% in Uruguay. Diversity in fluid type was noted when drinking with food between meals. Apart from China, most drinking occasions (> 75%) occurred at home.

CONCLUSIONS

Three distinct drinking behaviors were identified, namely, drinking with meals, drinking as a stand-alone activity, and a type of 'grazing' (i.e., frequent drinks throughout the day) behavior. Most drinking occasions occurred at home.

Nutritional therapy in autosomal dominant polycystic kidney disease

CKD-related nutritional therapy (NT) is a crucial cornerstone of CKD patients' treatment, but the role of NT has not been clearly investigated in autosomal dominant polycystic kidney disease (ADPKD). Several clinical studies have focused on new pharmacological approaches to delay cystic disease progression, but there are no data on dietary interventions in ADPKD patients. The aim of this paper is to analyze the evidence from the literature on the impact of five nutritional aspects (water, sodium, phosphorus, protein intake, and net acid load) in CKD-related ADPKD extrapolating-where information is unavailable-from what occurs in CKD non-ADPKD patients Sodium intake restriction could be useful in decreasing the growth rate of cysts. Although further evidence is needed, restriction of phosphorus and protein intake restriction represent cornerstones of the dietary support of renal non-ADPKD patients and common sense can guide their use. It could be also helpful to limit animal protein, increasing fruit and vegetables intake together with a full correction of metabolic acidosis. Finally, fluid intake may be recommended in the early stages of the disease, although it is not to be prescribed in the presence of moderate to severe reduction of renal function.

Thirst at Work Implies More Than Just Inadequate Facilities for Breaks

Early signs of dehydration, such as headaches, are not unusual in the working population. Even slight deficiencies of water intake may have negative effects on both health and performance. However, little is known about work-related fluid intake. We expect the daily experience of interruptions to distract from perceived thirst, resulting in reduced daily fluid intake. This effect may be more pronounced when the workload is generally less predictable due to the assignment of tasks that are beyond the definition of the worker's professional role (unreasonable tasks). Data were gathered from 29 female service employees across five workdays. Multilevel analyses revealed daily work interruptions to be negatively associated with fluid intake, especially when there were frequent unreasonable task-assignments. Results suggest that interruptions at work might reduce daily fluid intake. However, adequate allocation of tasks by managers can protect employees against insufficient drinking.

Water and fluid intake in the prevention and treatment of functional constipation in children and adolescents: is there evidence?

OBJECTIVE

To study the evidence on the role of water and fluid intake in the prevention and treatment of functional intestinal constipation in children and adolescents.

SOURCE OF DATA

A search was carried out in the Medline database (between 1966 and 2016) for all published articles containing the following words: constipation, water, and fluids, published in Portuguese, English, and Spanish. All original articles that assessed children and adolescents were selected by title and abstract. The references of these articles were also evaluated.

SYNTHESIS OF DATA

A total of 1040 articles were retrieved. Of these, 24 were selected for reading. The study included 11 articles that assessed children and adolescents. The articles were divided into two categories, those that evaluated water and fluid intake as a risk factor for intestinal constipation and those that evaluated their role in the treatment of intestinal constipation. Five articles were included in the first category. The criteria for assessing fluid intake and bowel rhythm were different in each study. Three studies demonstrated an association between low fluid intake and intestinal constipation. Regarding treatment, five articles with heterogeneous methodologies were found. None of them clearly identified the favorable role of fluid intake in the treatment of intestinal constipation.

CONCLUSION

There are few articles on the association between fluid intake and intestinal constipation. Epidemiological evidence indicates an association between lower fluid intake and intestinal constipation. Further clinical trials and epidemiological studies that consider the international recommendations for fluid intake by children and adolescents are required.

Assessing a Tool for Self-Monitoring Hydration Using Urine Color in Pregnant and Breastfeeding Women: A Cross-Sectional, Online Survey

BACKGROUND

Pregnant and breastfeeding women experience great changes in their total body water content and water dynamics. To support the accretion of total body water during pregnancy and compensate for the water lost through breast milk during breastfeeding, increased adequate intakes (AI) for total water have been established by various health authorities. Despite this widespread advice, several studies suggest that pregnant and breastfeeding women do not meet the AI for total water, suggesting the need to raise women's awareness on the importance of adequate water intake, particularly during pregnancy and breastfeeding, as well as to provide them with a simple means of monitoring their hydration on a day-to-day basis. A urine color (UC) scale recently has been validated for hydration monitoring in pregnant and breastfeeding women.

SUMMARY

We sought to develop a version of a tool based on the UC scale, using only images or illustrations, which could be understood by users of various nationalities and spoken languages. Pregnant and breastfeeding women (n = 1,275) from Brazil, Mexico, and Poland were shown 3 versions of the tool. Understanding, appreciation, simplicity and intent to use were evaluated using a questionnaire consisting of 26 items. Key Messages: Among the 3 versions tested, one tool emerged as the most highly understood (88% spontaneous understanding) and was highly appreciated by users (mean [SD]: 8.40 [2.20] out of 10). There were no differences between countries. Furthermore, 83% reported being very likely to use the tool daily. These results suggest that a simple tool based on the UC scale will help pregnant and breastfeeding women meet the AI for total water.

Pregnant and Breastfeeding Women: Drinking for Two?

The primary aim of this cross-sectional survey was to assess the total fluid intake (TFI; sum of drinking water and all other fluids) and the intake of water and all other types of beverages in a sample of pregnant and breastfeeding women representative of Java-Island, Indonesia. Therefore, 299 pregnant and 296 breastfeeding women completed a 7-day fluid-specific record. A secondary aim was to estimate the total water intake (TWI; sum of water from fluids and food moisture), and one 24-h recall was performed to determine water intake from food moisture. The median TFI of pregnant and breastfeeding women were 2,250 (1,800-2,800) and 2,360 (1,954-2,968) mL/day, respectively. The largest contributor to TFI was water (72 and 77% for pregnant/breastfeeding women, respectively). Pregnant women to the extent of 42% and 54% of breastfeeding women did not reach the adequate intake (AI) of water from fluids. In pregnant and breastfeeding women, the median water intake from foods was 592 and 613 mL/day, representing 21 and 20% of TWI. Concluding that a high proportion of the pregnant and breastfeeding subjects did not reach the AI of water from fluid, it seems important to put in place actions such as providing education materials and ensuring access to safe water. Moreover, future surveys should dedicate attention to the assessment of fluid intake and hydration status among pregnant and breastfeeding women in other countries.

Monitoring Body Water Balance in Pregnant and Nursing Women: The Validity of Urine Color

BACKGROUND

Urine osmolality (UOSM) reflects the renal regulation of excess fluid or deficit fluid, and therefore, serves as a marker of hydration status. Little is known about monitoring hydration in pregnant and lactating women despite significant physiological challenges to body water balance during that time. Therefore, we designed a study to assess if urine color (UCOL), an inexpensive and practical method, was a valid means of assessing urine concentration. Twenty-four hour UCOL was significantly correlated with 24 h UOSM in all women: pregnant, lactating, and control (r = 0.61-0.84, all p < 0.001). Utilizing a receiver operating characteristic statistical analysis, we found that 24 h and single sample UCOL had excellent diagnostic accuracy for identifying UOSM ≥500 mOsm·kg-1 in all women (area under the curve = 0.68-0.95, p < 0.001-0.46), and the UCOL that reflected this cut off was ≥4 on the UCOL chart.

SUMMARY

Therefore, UCOL is a valid marker of urine concentration and ultimately hydration status in pregnant, lactating, and non-pregnant, non-lactating women. For pregnant, lactating, and control women, the UCOL chart is a valid tool that can be used to monitor urine concentration in a single sample or over the course of the day via a 24 h sample. Key Message: Women who present with a UCOL of 4 or more likely have a UOSM ≥500 mOsm·kg-1. Given the positive health benefits associated with UOSM <500 mOsm·kg-1, women should aim for a 1, 2, or 3 on the UCOL chart. If a UCOL of ≥4 is observed, women should consider increasing fluid consumption to improve hydration status.

Effect of increased water intake on plasma copeptin in healthy adults

PURPOSE

Inter-individual variation in median plasma copeptin is associated with incident type 2 diabetes mellitus, progression of chronic kidney disease, and cardiovascular events. In this study, we examined whether 24-h urine osmolality was associated with plasma copeptin and whether increasing daily water intake could impact circulating plasma copeptin.

METHODS

This trial was a prospective study conducted at a single investigating center. Eighty-two healthy adults (age 23.6 ± 2.9 years, BMI 22.2 ± 1.5 kg/m², 50% female) were stratified based upon habitual daily fluid intake volumes: arm A (50-80% of EFSA dietary reference values), arm B (81-120%), and arm C (121-200%). Following a baseline visit, arms A and B increased their water intake to match arm C for a period of 6 consecutive weeks.

RESULTS

At baseline, plasma copeptin was positively and significantly associated with 24-h urine osmolality (p = 0.002) and 24-h urine specific gravity (p = 0.003) but not with plasma osmolality (p = 0.18), 24-h urine creatinine (p = 0.09), and total fluid intake (p = 0.52). Over the 6-week follow-up, copeptin decreased significantly from 5.18 (3.3;7.4) to 3.90 (2.7;5.7) pmol/L (p = 0.012), while urine osmolality and urine specific gravity decreased from 591 ± 206 to 364 ± 117 mOsm/kg (p < 0.001) and from 1.016 ± 0.005 to 1.010 ± 0.004 (p < 0.001), respectively.

CONCLUSIONS

At baseline, circulating levels of copeptin were positively associated with 24-h urine concentration in healthy young subjects with various fluid intakes. Moreover, this study shows, for the first time, that increased water intake over 6 weeks results in an attenuation of circulating copeptin.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02044679.

Association between fluid intake and mortality in critically ill patients with negative fluid balance: a retrospective cohort study

Background

Compared to positive fluid balance (FB), negative FB is associated with improved clinical outcomes in critically ill patients. However, as to whether achieving more negative FB can further improve outcomes has not been investigated. This study aimed to investigate whether more negative FB and restricted fluid intake were associated with improved outcomes in critically ill patients.

Method

Data were extracted from the Multi-parameter Intelligent Monitoring in Intensive Care III Database. Patients achieving negative FB at 48 hours after intensive care unit (ICU) admission were screened. The primary outcome was hospital mortality. Logistic models were built to explore the association between FB, fluid intake and mortality, using FB and fluid intake (both four levels) as design variables and using the linear spline function method.

Results

There were 2068 patients meeting the inclusion criteria. Compared to slight negative FB (level 1), there was a decreased tendency towards mortality with FB level 2 (OR 0.88, 95% CI 0.69–1.11) and level 3 (OR 0.79, 95% CI 0. 65–1.11); however, only extreme negative FB (level 4) was significant (OR 0.56, 95% CI 0. 33–0.95). Fluid intake and urine output were evenly distributed over the first 48 hours after ICU admission. Fluid intake was inversely associated with hospital mortality, with the OR decreased stepwise from level 2 (OR 0.73, 95% CI 0.56–0.96) to level 4 (OR 0.47, 95% CI 0.30–0.74), referred to level 1. Urine output also showed a similar pattern. Diuretic use was associated with higher mortality in both models.

Conclusion

In critically ill patients with negative FB, both increased fluid intake and urine output were associated with decreased hospital mortality. However, compared to slight FB, achieving more negative FB was not associated with reduced mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1692-3) contains supplementary material, which is available to authorized users.

The Effect of Fluid Intake Following Dehydration on Subsequent Athletic and Cognitive Performance: a Systematic Review and Meta-analysis

Background

The deleterious effects of dehydration on athletic and cognitive performance have been well documented. As such, dehydrated individuals are advised to consume fluid in volumes equivalent to 1.25 to 1.5 L kg⁻¹ body mass (BM) lost to restore body water content. However, individuals undertaking subsequent activity may have limited time to consume fluid. Within this context, the impact of fluid intake practices is unclear. This systematic review investigated the effect of fluid consumption following a period of dehydration on subsequent athletic and cognitive performance.

Methods

PubMed (MEDLINE), Web of Science (via Thomas Reuters) and Scopus databases were searched for articles reporting on athletic (categorized as: continuous, intermittent, resistance, sport-specific and balance exercise) or cognitive performance following dehydration of participants under control (no fluid) and intervention (fluid intake) conditions. Meta-analytic procedures determined intervention efficacy for continuous exercise performance.

Results

Sixty-four trials (n = 643 participants) derived from 42 publications were reviewed. Dehydration decreased BM by 1.3–4.2%, and fluid intake was equivalent to 0.4–1.55 L kg⁻¹ BM lost. Fluid intake significantly improved continuous exercise performance (22 trials), Hedges’ g = 0.46, 95% CI 0.32, 0.61. Improvement was greatest when exercise was performed in hotter environments and over longer durations. The volume or timing of fluid consumption did not influence the magnitude of this effect. Evidence indicating a benefit of fluid intake on intermittent (10 trials), resistance (9 trials), sport-specific (6 trials) and balance (2 trials) exercise and on cognitive performance (15 trials) was less apparent and requires further elucidation.

Conclusions

Fluid consumption following dehydration may improve continuous exercise performance under heat stress conditions, even when the body water deficit is modest and fluid intake is inadequate for complete rehydration.

Electronic supplementary material

The online version of this article (doi:10.1186/s40798-017-0079-y) contains supplementary material, which is available to authorized users.

Salt appetite is not increased in summer heat

We tested the hypothesis that salt appetite increases in summer heat due to increased sodium loss due to increased drinking and perspiration. A test battery in the same sample of healthy young people tested in summer and winter revealed no seasonal differences in salt appetite (or fluid intake) despite a 10 °C rise in mean environmental temperature. Unexpectedly, sweet preference is reduced in summer.

Recording of fluid, beverage and water intakes at the population level in Europe

The European Food Safety Authority's 2010 scientific opinion on dietary reference values for total water intakes was partly based on observed intakes in population groups. Large variability was observed, and it is unlikely that these differences can be explained by differences in climate, activity level and/or culture. This suggests that there are uncertainties in the methodologies used to assess water intake from food and fluids, including all types of beverages. To determine current methods for recording and reporting total water, beverages and fluid intakes, twenty-one European countries were surveyed using an electronic questionnaire. In total, twelve countries responded and ten completed surveys were summarised. Countries reported that their survey was representative of the population in terms of age and socio-economic status. However, a variety of methods were used - that is, repeated 24-h recalls, estimated food diaries and FFQ. None of the methods were validated to assess water and fluid intakes. The methods used to record liquid foods - for example, soup and diluted drinks - were inconsistent. Clarity and consistency on definitions of categories of beverages to facilitate comparisons between countries are needed. Recommendations for a unified approach to surveying and quantifying intake of water from fluids and foods are proposed.

A higher Mediterranean diet adherence and exercise practice are associated with a healthier drinking profile in a healthy Spanish adult population

PURPOSE

Very few studies have examined the association between beverage intake patterns and healthy lifestyle characteristics. Most of the research that has been carried out focuses on the consumption of soft drinks or alcohol and ignores the overall beverage pattern. The aim of this study is to evaluate the association between consumption of different types of beverage and physical exercise practice and MedDiet adherence.

METHODS

Cross-sectional information about fluid intake from different types of beverages was collected in 1262 men and women between 18 and 70 years old, using a 24-h fluid-specific diary over seven consecutive days. Physical exercise was evaluated with a self-reported questionnaire, and MedDiet adherence was assessed using a validated 14-item questionnaire. Both variables were classified into three categories.

RESULTS

Individuals with greater adherence to the MedDiet showed a higher intake of water and wine and a lower consumption of sweet regular beverages. Participants who engaged in more physical exercise consumed more water, milk and derivatives, juices and wine and less sweet regular beverages. Compared to the lowest category, the possibility of meeting the EFSA recommendations of total fluid intake was greater in individuals with eight or more points on the MedDiet adherence questionnaire [OR 1.94; 95 % CI 1.25-3.01] and in those who practice physical exercise three times a week or more [OR 1.71; 95 % CI 1.22-2.39]. Participants with a healthier lifestyle had a lower risk of exceeding the WHO's free-sugar recommendations only from beverages.

CONCLUSIONS

Participants with greater adherence to the MedDiet and who engaged in more physical exercise exhibit a healthier pattern of fluid intake.