Water intake and recurrent urinary tract infections prevention: economic impact analysis in seven countries

BACKGROUND

To estimate the economic impact of preventing urinary tract infections (UTI) by increasing water intake among women with recurrent UTI and low fluid intake across seven countries: France, United Kingdom, Spain, United States of America, Mexico, China and Australia.

METHODS

A Markov model was developed to compare costs and outcomes of UTIs associated with low fluid intake in women versus a strategy of primary prevention by increasing water intake. Model inputs were based on randomized controlled trial data which found that increasing water intake by 1.5 L/day decreased the risk of developing cystitis by 48% in women with low fluid intake and recurrent UTI. A time horizon of 10 years was used; outcomes were from the payer perspective and included both direct and indirect costs, reported in 2019 United States dollars ($). Discounting rates varied by country. Scenarios of increasing levels of compliance to the increased water intake strategy were evaluated.

RESULTS

The total cost of one UTI episode, including diagnostics, treatment and complications, ranged from $2164 (Mexico) to $7671 (Australia). Assuming 80% compliance with the increased water intake strategy over a 10-year time horizon, the number of UTIs prevented ranged from 435,845 (Australia) to 24150,272 (China), resulting in total savings of 286 million (Australia) to $4.4 billion (China). Across all countries, increased water intake resulted in lower cost and fewer UTIs compared with low water intake.

CONCLUSION

Preventing recurrent UTIs by increasing water intake would reduce both the clinical and economic burden associated with UTI. Public, healthcare professionals and patients should be made aware about the preventive positive impact of appropriate water intake on UTIs.

Fluid Intake Management in Maintenance Hemodialysis Using a Smartphone-Based Application: A Pilot Study

Rationale & Objective

Increased interdialytic weight gain (IDWG) has been associated with increased morbidity and mortality. We evaluated the usefulness and safety of a mobile application (app) that allows patients receiving maintenance hemodialysis to self-monitor their daily fluid intake.

Study Design

Within group comparison before or during intervention.

Setting & Participants

Patients receiving maintenance hemodialysis with mean IDWG of <4%.

Exposure

Participants were trained to use a smartphone-based app, FiApp that allowed them to record fluid intake and compare with individual targeted daily fluid intake determined by the nephrologist.

Outcomes

The primary study outcome was the association between IDWG and fluid intake recorded in the FiApp. Secondary outcomes included FiApp safety and usage. Patient interviews were performed at weeks 1 and 4 to collect information regarding FiApp usability and recommendations for app improvements.

Analytical Approach

Mean, median, and standard deviation.

Results

Eighteen of 25 patients completed the full 4-week study, provided all app data, and completed 2 patient interviews. The mean 4-week IDWG during app use was similar to the baseline mean 4-week IDWG before app use; however, 61% of the participants had a decrease in IDWG when using the app compared with IDWG at baseline. Of the 18 participants who completed the study, only 1 had a mean 4-week IDWG that was 20% higher than that at baseline. The app was used on ≥80% of the days by 13 (72%) of 18 participants, and was used every day in 7 (39%) of 18 participants. The mean relationship between fluid reported in the app and fluid consumed was 40%.

Limitations

This safety study recruited patients who had IDWG of <4%.

Conclusions

A smartphone-based app can be safely used to help patients receiving maintenance hemodialysis track and control fluid intake. Motivated patients were able to decrease IDWG despite baseline IDWG being <4% of the body weight.

Trial Registration

NCT03759847.

Plain-Language Summary

Patients receiving maintenance hemodialysis struggle to limit fluid intake. Excess fluid intake can lead to adverse cardiovascular events. We developed a smartphone app to help patients receiving dialysis self-monitor their fluid intake. In this safety study in patients receiving dialysis with an interdialytic weight gain of <4% of the body weight, more than half of the patients were able to decrease their interdialytic fluid intake while using the app, and only 1 patient had an increase in interdialytic weight gain of >20% while using the app. Information gleaned from structured patient interviews will be used to refine this app.

Dietary Fibers and Proteins Modulate Behavior via the Activation of Intestinal Gluconeogenesis

INTRODUCTION

Several studies have suggested that diet, especially the one enriched in microbiota-fermented fibers or fat, regulates behavior. The underlying mechanisms are currently unknown. We previously reported that certain macronutrients (fermentable fiber and protein) regulate energy homeostasis via the activation of intestinal gluconeogenesis (IGN), which generates a neural signal to the brain. We hypothesized that these nutriments might control behavior using the same gut-brain circuit.

METHODS

Wild-type and IGN-deficient mice were fed chow or diets enriched in protein or fiber. Changes in their behavior were assessed using suited tests. Hippocampal neurogenesis, extracellular levels of serotonin, and protein expression levels were assessed by immunofluorescence, in vivo dialysis, and Western blotting, respectively. IGN was rescued by infusing glucose into the portal vein of IGN-deficient mice.

RESULTS

We show here that both fiber- and protein-enriched diets exert beneficial actions on anxiety-like and depressive-like behaviors. These benefits do not occur in mice lacking IGN. Consistently, IGN-deficient mice display hallmarks of depressive-like disorders, including decreased hippocampal neurogenesis, basal hyperactivity, and deregulation of the hypothalamic-pituitary-adrenal axis, which are associated with increased expression of the precursor of corticotropin-releasing hormone in the hypothalamus and decreased expression of the glucocorticoid receptor in the hippocampus. These neurobiological alterations are corrected by portal glucose infusion mimicking IGN.

CONCLUSION

IGN translates nutritional information, allowing the brain to finely coordinate energy metabolism and behavior.

Anxiolytic- and Antidepressant-Like Effects of Fish Oil-Enriched Diet in Brain-Derived Neurotrophic Factor Deficient Mice

Despite significant advances in the understanding of the therapeutic activity of antidepressant drugs, treatment-resistant depression is a public health issue prompting research to identify new therapeutic strategies. Evidence strongly suggests that nutrition might exert a significant impact on the onset, the duration and the severity of major depression. Accordingly, preclinical and clinical investigations demonstrated the beneficial effects of omega-3 fatty acids in anxiety and mood disorders. Although the neurobiological substrates of its action remain poorly documented, basic research has shown that omega-3 increases brain-derived neurotrophic factor (BDNF) levels in brain regions associated with depression, as antidepressant drugs do. In contrast, low BDNF levels and hippocampal atrophy were observed in animal models of depression. In this context, the present study compared the effects of long-lasting fish oil-enriched diet, an important source of omega-3 fatty acids, between heterozygous BDNF^+/- mice and their wild-type littermates. Our results demonstrated lower activation of Erk in BDNF^+/- mice whereas this deficit was rescued by fish oil-enriched diet. In parallel, BDNF^+/- mice displayed elevated hippocampal extracellular 5-HT levels in relation with a local decreased serotonin transporter protein level. Fish oil-enriched diet restored normal serotonergic tone by increasing the protein levels of serotonin transporter. At the cellular level, fish oil-enriched diet increased the pool of immature neurons in the dentate gyrus of BDNF^+/- mice and the latter observations coincide with its ability to promote anxiolytic- and antidepressant-like response in these mutants. Collectively, our results demonstrate that the beneficial effects of long-term exposure to fish oil-enriched diet in behavioral paradigms known to recapitulate diverse abnormalities related to the depressive state specifically in mice with a partial loss of BDNF. These findings contrast with the mechanism of action of currently available antidepressant drugs for which the full manifestation of their therapeutic activity depends on the enhancement of serotoninergic and BDNF signaling. Further studies are warranted to determine whether fish oil supplementation could be used as an add-on strategy to conventional pharmacological interventions in treatment-resistant patients and relevant animal models.

High-fat diet-induced metabolic disorders impairs 5-HT function and anxiety-like behavior in mice

BACKGROUND AND PURPOSE

The link between type 2 diabetes mellitus (T2DM) and depression is bidirectional. However, the possibility that metabolic disorders may elicit anxiogenic-like/depressive-like symptoms or alter the efficacy of antidepressant drugs remains poorly documented. This study explored the influence of T2DM on emotionality and proposed a therapeutic strategy that might be used in depressed diabetic patients.

EXPERIMENTAL APPROACH

Mice were fed a high-fat diet (HFD) and subjected to a full comprehensive metabolic and behavioural analysis to establish correlations between metabolic and psychiatric disorders. In vivo intra-hippocampal microdialysis was also applied to propose a mechanism underpinning the phenotype of mice fed the HFD. Finally, we tested whether chronic administration of the selective 5-HT reuptake inhibitor escitalopram or HFD withdrawal could reverse HFD-induced metabolic and behavioural anomalies.

KEY RESULTS

The increased body weight, hyperglycaemia and impaired glucose tolerance in response to HFD were correlated with anxiogenic-like/depressive-like symptoms. Moreover, this phenotype was associated with decreased extracellular 5-HT levels in the hippocampus which may result from increased sensitivity of the dorsal raphe 5-HT1A autoreceptor. Interestingly, the beneficial effect of prolonged administration of escitalopram was abolished in HFD-fed mice. On the contrary, HFD withdrawal completely reversed metabolic impairments and positively changed symptoms of anxiety, although some behavioural anomalies persisted.

CONCLUSIONS AND IMPLICATIONS

Our data provide clear-cut evidence that both pathologies are finely correlated and associated with impaired 5-HT mediated neurotransmission in the hippocampus. Further experiments are warranted to define the most adequate strategy for the treatment of such co-morbidity.

LINKED ARTICLES

This article is part of a themed section on Updating Neuropathology and Neuropharmacology of Monoaminergic Systems. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.13/issuetoc.

Co-activation of VTA DA and GABA neurons mediates nicotine reinforcement

Smoking is the most important preventable cause of mortality and morbidity worldwide. This nicotine addiction is mediated through the nicotinic acetylcholine receptor (nAChR), expressed on most neurons, and also many other organs in the body. Even within the ventral tegmental area (VTA), the key brain area responsible for the reinforcing properties of all drugs of abuse, nicotine acts on several different cell types and afferents. Identifying the precise action of nicotine on this microcircuit, in vivo, is important to understand reinforcement, and finally to develop efficient smoking cessation treatments. We used a novel lentiviral system to re-express exclusively high-affinity nAChRs on either dopaminergic (DAergic) or γ-aminobutyric acid-releasing (GABAergic) neurons, or both, in the VTA. Using in vivo electrophysiology, we show that, contrary to widely accepted models, the activation of GABA neurons in the VTA plays a crucial role in the control of nicotine-elicited DAergic activity. Our results demonstrate that both positive and negative motivational values are transmitted through the dopamine (DA) neuron, but that the concerted activity of DA and GABA systems is necessary for the reinforcing actions of nicotine through burst firing of DA neurons. This work identifies the GABAergic interneuron as a potential target for smoking cessation drug development.

Differential diagnosis of common female genitourinary complaints

The symptoms and diagnosis of the three most common female bladder-urethral dysfunctions (infection, stress incontinence, and irritable bladder syndrome) are examined so that the practitioner may better differentiate between these problems and some of their counterparts. Cystitis cystica, urethritis, and radiation cystitis are among the less common infections and are frequently missed. Other conditions can be mistaken for infections: urethral diverticulum, Hunner's ulcer, atrophic vaginitis, urethral stenosis. Stress urinary incontinence, arising from abnormal bladder-urethral unit physiology or from obesity, can benefit from Kegel's exercise to strengthen the external sphincter and pubococcygeus muscles. For irritable bladder syndrome, which is often misdiagnosed, a bladder drill with increasing voiding intervals is useful. Patient understanding of bladder function and the need for retraining is also important.