Early Coaching to Increase Water Intake in CKD

<b><i>Introduction:</i></b> In observational studies, increased water intake improves kidney function but not in adults with CKD stage 3 and more. CKD WIT trial has shown a nonsignificant gradual decline in kidney function after 1 year of coaching to increase water intake (CIWI) [<xref ref-type="bibr" rid="ref1">1</xref>]. We propose that CIWI may benefit in CKD stage 1–2 (G1 and G2) and depends on functional renal functional reserve (RFR) [<xref ref-type="bibr" rid="ref2">2</xref>, <xref ref-type="bibr" rid="ref3">3</xref>]. <b><i>Objective:</i></b> Parallel-group randomized trial was aimed to determinate the effectiveness of CIWI dependence of estimated glomerular filtration rate (eGFR) stage and RFR in adults with CKD 1–2 stages. <b><i>Methods:</i></b> CKD WIT trial was taken as the basis for prospective multicenter randomized trial named “Early Coaching to Increase Water Intake in CKD (ECIWIC).” The primary outcome was the change in kidney function by eGFR from baseline to 12 months. Secondary outcomes included 1-year change in urine albumin/Cr ratio, and patient-reported overall quality of health (QH) ranged from 0 (worst possible) to 10 (best possible). CIWI aimed to have the diuresis being 1.7–2 L. There were 4 groups with nondiet sodium restriction which consisted of 31 patients each: 2 groups with CKD G1 and CKD G2, undergoing CIWI and 2 others with CKD G1 and CKD G2 without CIWI (Fig. 1a). Overall checks were made at 0, 6, and 12 months. RFR evaluation was performed using 0.45% sodium chloride oral solution. <b><i>Results:</i></b> Of our randomized 124 patients (mean age 53.2 years; men 83 [67%], 0 died), mean change in 24-h urine volume was 0.6 L per day in G1 with CIWI group and 0.5 L in G2. No statistically significant data on eGFR depending CIWI were obtained (Fig. <xref ref-type="fig" rid="f01">1</xref>b). However, the trend suggests that CIWI improves eGFR in CKD G1 (from 95 to 96 mL/min/1.73 m²) and preserves eGFR decline in CKD G2 (78–78). The QH values were also preserved (from 7 to 7 in G1 and G2 groups). Although coaching to maintain the same water intake did not preserve physiological and pathological eGFR decreasing in CKD G1-2 (G1 from 96 to 93, G2 from 76 to 73; <i>t</i> = 0.6, <i>p</i> = 0.29, and <i>p</i> ≤ 0.05 in all groups) and the QH was declined (from 7 to 6 in both groups). An individual analysis of the RFR has shown that patients with RFR more than 50% (G1 19 patients, 61%, and G2 13 patients, 42%) had reliable preservation of eGFR with its increase of 1.5 mL/min on CIWI, while patients with low functional renal reserve had a drop of eGFR at 1.1 mL/min/m² within 12 months. Patients with low normal serum sodium levels have shown worse results on CIWI. <b><i>Conclusions:</i></b> With CKD G1, the CIWI leads to the preservation of the renal function with its increase of GFR per 1 mL/min/m²/per year in comparison with the same water intake. In CKD G2, the CIWI prevents physiological and pathological loss of renal function, and RFR above 50% aids restoration of eGFR both in CKD G1-2. ECIWIC trial demonstrates benefit of CIWI in patients with CKD 1–2 and preserved RFR.

Distinct CCK-positive SFO neurons are involved in persistent or transient suppression of water intake

The control of water-intake behavior is critical for life because an excessive water intake induces pathological conditions, such as hyponatremia or water intoxication. However, the brain mechanisms controlling water intake currently remain unclear. We previously reported that thirst-driving neurons (water neurons) in the subfornical organ (SFO) are cholecystokinin (CCK)-dependently suppressed by GABAergic interneurons under Na-depleted conditions. We herein show that CCK-producing excitatory neurons in the SFO stimulate the activity of GABAergic interneurons via CCK-B receptors. Fluorescence-microscopic Ca2+ imaging demonstrates two distinct subpopulations in CCK-positive neurons in the SFO, which are persistently activated under hyponatremic conditions or transiently activated in response to water drinking, respectively. Optical and chemogenetic silencings of the respective types of CCK-positive neurons both significantly increase water intake under water-repleted conditions. The present study thus reveals CCK-mediated neural mechanisms in the central nervous system for the control of water-intake behaviors.

PSXI-17 Increasing the number of water troughs do not increase water intake or improve calf performance

Provision of adequate quantity of water is essential for cattle as it can affect their health and growth. In addition, during summer months, the amount of water that calves can drink may double, limiting water access. One hundred and eight Holstein male calves (241 ± 3.1 Kg and 184 ± 0.9 d of age) were used in a randomized design to evaluate the effect of increasing from one to two water troughs per pen on water intake, performance and calf behavior over time. Calves were allocated in 6 pens (3 pens per treatment; 18 calves per pen) with one computerized concentrate feeder and one straw feeder with 5 feeding spaces. Pens were assigned to one of the two treatments according to the number of water troughs, a singles water trough (SWT) or a double water trough (DWT). Concentrate and water intake was recorded daily, and body weight (BW) and behavior fortnightly. Data were analyzed using a mixed-effects model with repeated measures including treatment, period and their interaction as main effect and pen per treatment as random effect. Final BW, average daily gain, water and concentrate intake were not affected by the number of water trough in the pen, as well as carcass weight and dressing percentage. However, water intake increased (P &lt; 0.001) by period with an average water intake per calf of 21 L/day in calves with 241 d of age in February, to 51 L/day in calves with 409 d of age in August. Sexual and agonistic behaviors such as grooming, oral non-nutritive behaviors, fighting and mounting did not differ between treatments. The provision of an extra water trough per pen did not improve calf performance nor increase water intake even in summer month.

“I know it's just pouring it from the tap, but it's not easy”: Motivational processes that underlie water drinking

Water drinking behaviour is under-researched despite the prevalence and adverse health consequences of underhydration. We conducted a qualitative exploration into the motivational processes that affect water drinking. We interviewed and analysed data from 60 participants using thematic analysis. Our findings suggest that participants form and maintain situated water drinking habits, so that within certain situations they report regularly drinking water. However, the way participants situated their water drinking had consequences on the amount and consistency of their water intake. Participants who situated their water intake in one key situation (e.g., drinking water during their work routine), had low and inconsistent intake when they left this situation. Some situations happened so infrequently during the day (e.g., drinking before bed) that participants’ daily water intake was low. Many participants reported drinking water in reaction to thirst cues, but these were easily suppressed or went unnoticed, so that water drinking was inconsistent. Participants who saw drinking water as part of their self-identity had consistent and high water intake across a variety of internal and external situations. Few participants perceived water as positive or understood the importance of hydration. Many participants also lacked insight into strategies to increase water intake, which lead to ineffective attempts at behavioural change. Participants’ mentions of cues of dehydration and their responses to a urine colour chart further suggested that many participants were possibly underhydrated. Our findings suggest that health interventions and practitioners attempting to increase water intake need to increase knowledge about the importance of hydration, and encourage individuals to develop effective situated water drinking habits.

Harmonized Cross-Sectional Surveys Focused on Fluid Intake in Children, Adolescents and Adults: The Liq.In7 Initiative

Objective: To assess the intake of water and all other beverages in children, adolescents and adults. Methods: Three thousand six hundred eleven children (8 ± 2 years), 8,109 adolescents (13 ± 2 years) and 16,276 adults (40 ± 14 years) (47% men) were recruited in 15 cross-sectional surveys (liquid intake across 7 days, Liq.In7 study) and completed a 7-day fluid-specific record to assess total fluid intake (TFI), where TFI was defined as the sum of drinking water and other type of beverages. Results: The median TFI was 1.2, 1.2 and 1.8 liters/day in children, adolescents and adults respectively, with important differences observed between countries. Only 39% of children, 25% of adolescents and 51% of adults met the European Food Safety Authority adequate intake (AI) recommendations of water from fluids. In the surveys of Spain, France, Belgium, Germany, Turkey, Iran, Indonesia and China, water was the major contributor (47-78%) to TFI. In the adult surveys of UK, Poland, Japan and Argentina, hot beverages were the highest contributor to TFI. The fluid intake of children and adolescents in Mexico, Brazil, Argentina and Uruguay was characterized by a contribution of juices and sweet beverages that was as important as the contribution of water to TFI. Conclusion: Given that a relatively high proportion of subjects, especially children and adolescents, failed to meet the recommended AI of water from fluids and that water intake was not the highest contributor to TFI in all countries, undertaking actions to increase water intake are warranted.