Nana Waldréus

Thirst in heart failure: a systematic literature review

Although patients with heart failure (HF) may suffer from severe thirst, this has received little attention in scientific studies. A systematic literature review was conducted to identify and analyse data on thirst in HF.

Thirst in the elderly with and without heart failure

Elderly patients with heart failure (HF) may be troubled by thirst, despite the fact that elderly have an impaired ability to sense thirst. The present study was undertaken to compare the intensity of thirst in patients with and without HF and to evaluate how this symptom relates to the health-related quality of life and indices of the fluid balance. Forty-eight patients (mean age 80 years) admitted to hospital with worsening HF (n = 23) or with other acute illness (n = 25) graded their thirst and estimated their health-related quality of life (HRQoL). Serum sodium was measured and urine samples were assessed for color and electrolyte content. The HF patients reported significantly more intensive thirst (median = 75 mm) compared with those in the control group (median = 25 mm; p < 0.0001). There was no statistically significant relationship between thirst and HRQoL, which was low overall. Serum sodium and urine color did not differ significantly between the groups, but the urine of the HF patients had a lower sodium concentration and osmolality. We conclude that elderly patients with worsening HF have considerably increased thirst and, hence, intense thirst should be regarded as a symptom of HF.

Fluid retention index predicts the 30-day mortality in geriatric care.

Abstract The incidence and medical consequences of dehydration and fluid retention in senior citizens are unclear. The present study used urine sampling to detect renal conservation of water, which is an early sign of dehydration, and assessed its relationship to mortality in elderly patients admitted for acute hospital care. A urine sample was collected from 256 patients (mean age 82 years) and analyzed for color, specific gravity and osmolality. These markers were used to calculate a composite index of fluid retention, which was indicated by urine color ≥ 4, specific gravity ≥ 1.020 and osmolality ≥ 600 mOsmol/kg as suggested from eight previous studies of exercise-induced dehydration, of which one extends to age 69. Concentrated urine consistent with dehydration was present in 39 (16%) of the patients. This finding was relatively more common among those with confusion and/or dementia, but less common in patients with medical disease, and in those taking diuretics daily. Patients with such fluid retention had a higher 30-day mortality when compared to those who were euhydrated (21% versus 8%; p < 0.03). A difference of 10% remained at three months and one year after the admission to hospital. Concentrated urine consistent with fluid retention was found in 16% of the geriatric patients admitted to hospital for acute care. In these patients the mortality within 30 days was almost tripled compared to those who were euhydrated.

Fluid restriction in patients with heart failure: how should we think?

Background/aim: Fluid restriction has long been considered one of the cornerstones in self-care management of patients with heart failure. The aim of this discussion paper is to discuss fluid restriction in heart failure and propose advice about fluid intake in heart failure patients. Results: Although there have been seven randomised studies on fluid restriction in heart failure patients, the effect of fluid restriction on its own were only evaluated in two studies. In both studies, a stringent fluid restriction compared to a liberal fluid intake was not more beneficial with regard to clinical stability or body weight. In the other studies fluid restriction was part of a larger study intervention including, for example, individualised dietary recommendations and follow-up by telephone. Thus, the effect of fluid restriction on its own has been poorly evaluated. Conclusion: Fluid restriction should not be recommended to all heart failure patients. However, temporary fluid restriction can be considered in decompensated heart failure and/or patients with hyponatremia. Tailored fluid restriction based on body weight (30 ml/kg per day) seems to be most reasonable. To increase adherence to temporary fluid restriction, education, support and planned evaluations can be recommended.

Thirst response to acute hypovolaemia in healthy women and women prone to vasovagal syncope.

The present study measured self-perceived thirst and plasma angiotensin II (ATII) concentrations during graded hypovolaemic stress, induced by lower body negative pressure (LBNP), to elucidate the dependence of thirst on haemodynamics. A total of 24 women aged between 20 and 36 (mean age, 23) years rated their thirst on a visual analogue scale, graded from 0 to 100, when LBNP of 20, 30 and 40 mmHg was applied. Half of the women had a history of vasovagal syncope (VVS). The results showed that the thirst score increased three-fold when LBNP was applied, from 11 (median; 25th-75th percentiles, 9-25) to 34 (27-53; P<0.001). The women in the VVS group had twice as great an increase as those without a history of VVS (P<0.02). The plasma ATII concentration increased significantly in response to LBNP, both in the VVS group and in the control group, but the changes did not correlate with thirst. Application of LBNP decreased systolic and mean arterial pressures, cardiac output and pulse pressure (P<0.001 for all), but thirst correlated only with increase in heart rate and, independently, with reduction of mean arterial pressure. In conclusion, thirst and ATII increase in response to hypovolaemic stress, but are not statistically related. The haemodynamic parameter that was most strongly related to thirst was tachycardia.

Changes in Thirst Intensity During Optimization of Heart Failure Medical Therapy by Nurses at the Outpatient Clinic.

Background:Thirst can be aggravated in patients with heart failure (HF), and optimization of HF medication can have positive impact on thirst. Objectives:The aims of this study were to describe changes in thirst intensity and to determine factors associated with high thirst intensity during optimization of HF medication. Methods and Results:Patients with HF (N = 66) who were referred to an HF clinic for up-titration of HF medication were included. Data were collected during the first visit to the clinic and at the end of the treatment program. Data were dichotomized by the median visual analog scale score for thirst, dividing patients into 2 groups: low thirst intensity (0–20 mm) and high thirst intensity (>20 mm on a visual analog scale of 0–100 mm). In total, 67% of the patients reported a higher thirst intensity after the HF up-titration program. There was no difference in thirst intensity between the patients who reached target doses and those who did not. Plasma urea level (odds ratio, 1.33; 95% confidence interval, 1.07–1.65) and fluid restriction (odds ratio, 6.25; 95% confidence interval, 1.90–20.5) were independently associated with high thirst intensity in patients with HF. Conclusions:Thirst intensity increased in two-thirds of the patients during a time period of optimization of HF medication. Fluid restriction and plasma urea levels were associated with high thirst intensity.

O3.20: Non-invasive clinical and physical signs, symptoms and indications for identification of impending and current water-loss dehydration in older people: a diagnostic accuracy systematic review

Introduction Water-loss dehydration is common in older people and associated with excess morbidity and mortality, but it is unclear which signs/symptoms identify dehydration in this group. Diagnostic accuracy of possible clinical and physical signs, symptoms and indications of water-loss dehydration in older people were assessed against serum osmolality or weight change (reference standards)1. Methods Structured searches were run in seven databases. Assessment of inclusion, data extraction and assessment of validity were duplicated. Where data sets included index tests and a reference standard, but were not analysed for diagnostic accuracy, reviewers analysed the data. Diagnostic accuracy of each sign, symptom or indicator was assessed against the best reference standard, and data presented in sensitivity and specificity forest plots. Pre-set minimum sensitivity was 60%, specificity 75%. Secondary analyses created receiver operating characteristic (ROC) curves for continuous tests. Results We included 24 studies (3 using published data, 21 analysing raw data sets) reporting 67 tests. No index tests were reproducibly usefully diagnostic of water-loss dehydration in older people, but promising signs/symptoms, which need further assessment, are shown in the table. There was sufficient evidence to suggest that some signs/symptoms should not be used to indicate dehydration (table). Conclusions No single sign/symptom was diagnostic of water-loss dehydration in older people. Individual signs should not be used in this population to indicate dehydration as they will miss many with dehydration, and wrongly label those adequately hydrated. Promising signs identified by this review need to be further assessed. 1. Hooper L et al, Cochrane Library (protocol) 2011: CD009647-DOI:1002/14651858.

Effects of tap water, electrolyte solution, and spontaneous and furosemide-stimulated urinary excretion on thirst.

AIM To contrast the effects of various modifications of body fluid volumes on thirst as reported by healthy volunteers. METHODS Ten male volunteers aged between 19 and 37 years (mean 22 years) underwent four experiments each, which comprised infusion of 400-800 mL of acetated Ringers solution and intake of 600 mL of tap water. Half of the experiments were preceded by volume depletion (median 1.7 L) with furosemide. A visual analogue scale (0-100 mm) was used to assess perceived thirst during each experiment. RESULTS Volume depletion (P < 0.001) and tap water (P < 0.03) both affected thirst by 13 mm per L of fluid, whereas spontaneous diuresis and infusion of Ringers acetate did not significantly change the thirst rating (multiple regressions). More detailed analyses showed that the volume depletion increased the median (25th-75th percentiles) thirst rating from 28 mm (21-43) to 59 mm (46-72, P < 0.001) while no change occurred in those who were only slightly thirsty (< 30 mm) before the volume depletion began. Ringers solution alleviated thirst in those who were very thirsty, but tended to increase thirst in the volunteers who were not thirsty before the infusion. Similarly, hydration with tap water decreased thirst (by 24 mm, P < 0.04) in those who were thirsty (> 60 mm) while the others reported no change. CONCLUSION The change in thirst rating during volume depletion, administration of Ringers acetate, and ingestion of tap water were all dependent on the thirst rating obtained when the manipulation of the body fluid volume was initiated.

Urine measurement indicates the plasma brain natriuretic peptide concentration during optimization of heart failure treatment.

Abstract Aim: To assess the correlation between the amino-terminal pro-hormone brain natriuretic peptide (NT-proBNP) concentration in blood and urine during a period when actively adjusting the treatment of heart failure (HF). Methods: Plasma and urine analyses of NT-proBNP were compared in 51 patients on admission to and discharge from a nurse-led outpatient clinic where HF treatment was optimized. The median time between the two measurements was 42 days. Correlations were analyzed using linear regression, where R2 is the degree of variability in the plasma NT-proBNP concentration that can be accounted for by the urinary NT-proBNP. Results: There was a statistically significant linear relationship between the urine and plasma concentrations of NT-proBNP on both occasions, but R2 varied greatly depending on how the data were presented. The correlation between the raw data showed an R2 of only 30%, and it almost doubled upon logarithm transformation, which shows that the variability (error) was concentration-dependent. Correction of the urinary NT-proBNP for urinary creatinine further increased R2 for the logarithm-transformed correlation to 68% on admission and 76% on discharge. The highest R2 (77%) was obtained when the relative changes in urinary NT-proBNP/creatinine between admission and discharge were compared with the corresponding relative changes in the plasma concentration. The sensitivity and specificity of the urine in indicating plasma concentration changes > 10% were 82% and 86%, respectively. Conclusion: Relative changes in plasma NT-proBNP could be reliably estimated from urine samples during a period of optimization of HF treatment.