Dehydration among Long-Term Care Elderly Patients with Oropharyngeal Dysphagia

The Clinical Frailty Scale as a Risk Assessment Tool for Dysphagia in Older Inpatients: A Cross-Sectional Study

BACKGROUND

Dysphagia is a common problem with potentially serious consequences including malnutrition, dehydration, pneumonia, and death. However, there are challenges in screening for dysphagia in older adults. We assessed the feasibility of using the Clinical Frailty Scale (CFS) as a risk assessment tool for dysphagia.

METHODS

This cross-sectional study was conducted at a tertiary teaching hospital from November 2021 to May 2022 and included 131 older patients (age ≥65 years) admitted to acute wards. We used the Eating Assessment Tool-10 (EAT-10), which is a simple measure for identifying individuals at risk of dysphagia, to assess the relationship between EAT-10 score and frailty status as measured using the CFS.

RESULTS

The mean age of the participants was 74.3±6.7 years, and 44.3% were male. Twenty-nine (22.1%) participants had an EAT-10 score ≥3. The CFS was significantly associated with an EAT-10 score ≥3 after adjusting for age and sex (odds ratio=1.48; 95% confidence interval [CI], 1.09-2.02). The CFS was able to classify the presence of an EAT-10 score ≥3 (area under the receiver operating characteristic [ROC] curve=0.650; 95% CI, 0. 544-0.756). The cutoff point for predicting an EAT-10 score ≥3 was a CFS of 5 according to the highest Youden index, with a sensitivity of 82.8% and a specificity of 46.1%. The positive and negative predictive values were 30.4% and 90.4%, respectively.

CONCLUSION

The CFS can be used as a tool to screen for the risk of swallowing difficulty in older inpatients to determine clinical management encompassing drug administration routes, nutritional support, prevention of dehydration, and further evaluation of dysphagia.

Evaluation of Esophageal Dysphagia in Elderly Patients

PURPOSE OF REVIEW

While guidelines exist for the evaluation and management of esophageal dysphagia in the general population, dysphagia disproportionately affects the elderly. In this article, we reviewed the literature on evaluating esophageal dysphagia in elderly patients and proposed a diagnostic algorithm based on this evidence.

RECENT FINDINGS

In older patients, dysphagia is often well compensated for by altered eating habits and physiologic changes, underreported by patients, and missed by healthcare providers. Once identified, dysphagia should be differentiated into oropharyngeal and esophageal dysphagia to guide diagnostic workup. For esophageal dysphagia, this review proposes starting with endoscopy with biopsies, given its relative safety even in older patients and potential for interventional therapy. If endoscopy shows a structural or mechanical cause, then further cross-sectional imaging should be considered to assess for extrinsic compression, and same session endoscopic dilation should be considered for strictures. If biopsies and endoscopy are normal, then esophageal dysmotility is more likely, and high-resolution manometry and additional workup should be performed following the updated Chicago Classification. Even after diagnosis of the root cause, complications including malnutrition and aspiration pneumonia should also be assessed and monitored, as they both result from and can further contribute to dysphagia. The successful evaluation of esophageal dysphagia in elderly patients requires a thorough, standardized approach to collecting a history, selection of appropriate diagnostic workup, and assessment of risk of potential complications, including malnutrition and aspiration.

Hydration Status in Older Adults: Current Knowledge and Future Challenges

Adequate hydration is essential for the maintenance of health and physiological functions in humans. However, many older adults do not maintain adequate hydration, which is under-recognized and poorly managed. Older adults are more vulnerable to dehydration, especially those living with multiple chronic diseases. Dehydration is associated with adverse health outcomes in older adults, and acts as an independent factor of the hospital length of stay, readmission, intensive care, in-hospital mortality, and poor prognosis. Dehydration is a prevalent health problem in older adults, accounting for substantial economic and social burden. This review attempts to provide current knowledge of hydration including patterns of body water turnover, the complex mechanisms behind water homeostasis, the effects of dehydration on the health of the body, and practical guidance for low-intake dehydration in older adults.

Development and validation of a nomogram for predicting dysphagia in long-term care facility residents

BACKGROUND

Dysphagia is a common problem that can seriously affect the health of elderly residents in long-term care facilities. Early identification and targeted measures can significantly reduce the incidence of dysphagia.

AIM

This study aims to establish a nomogram to evaluate the risk of dysphagia for elderly residents in long-term care facilities.

METHODS

A total of 409 older adults were included in the development set, and 109 were included in the validation set. Least absolute shrinkage selection operator (LASSO) regression analysis was used to select the predictor variables, and logistic regression was used to establish the prediction model. The nomogram was constructed based on the results of logistic regression. The performance of the nomogram was evaluated by receiver operating characteristic (ROC) curve, calibration, and decision curve analysis (DCA). Internal validation was performed using tenfold cross-validation with 1000 iterations.

RESULTS

The predictive nomogram included the following variables: stroke, sputum suction history (within one year), Barthel Index (BI), nutrition status, and texture-modified food. The area under the curve (AUC) for the model was 0.800; the AUC value for the internal validation set was 0.791, and the AUC value for the external validation set was 0.824. The nomogram showed good calibration in both the development set and validation set. Decision curve analysis (DCA) demonstrated that the nomogram was clinically valuable.

DISCUSSION

This predictive nomogram provides a practical tool for predicting dysphagia. The variables included in this nomogram were easy to assess.

CONCLUSIONS

The nomogram may help long-term care facility staff identify older adults at high risk for dysphagia.

Rheological Issues on Oropharyngeal Dysphagia

There is an increasing proof of the relevance of rheology on the design of fluids for the diagnosis and management of dysphagia. In this sense, different authors have reported clinical evidence that support the conclusion that an increase in bolus viscosity reduces the risks of airway penetration during swallowing. However, this clinical evidence has not been associated yet to the definition of objective viscosity levels that may help to predict a safe swallowing process. In addition, more recent reports highlight the potential contribution of bolus extensional viscosity, as elongational flows also develops during the swallowing process. Based on this background, the aim of this review paper is to introduce the lecturer (experts in Dysphagia) into the relevance of Rheology for the diagnosis and management of oropharyngeal dysphagia (OD). In this sense, this paper starts with the definition of some basic concepts on Rheology, complemented by a more extended vision on the concepts of shear viscosity and elongational viscosity. This is followed by a short overview of shear and elongational rheometrical techniques relevant for the characterization of dysphagia-oriented fluids, and, finally, an in-depth analysis of the current knowledge concerning the role of shear and elongational viscosities in the diagnosis and management of OD (shear and elongational behaviors of different categories of dysphagia-oriented products and contrast fluids for dysphagia assessment, as well as the relevance of saliva influence on bolus rheological behavior during the swallowing process).

Evaluation of wiping edible sesame oils in the oral cavities of hospitalised older patients who resist oral hygiene management

Context

One of the causes of aspiration pneumonia is poor oral hygiene. We need care methods that caregivers can quickly, safely and inexpensively implement for convalescents with inadequate self-care. Edible sesame oil containing sesamin or sesaminol has already been shown to inhibit bacterial and fungal growth and have a vasodilating effect.

Aims

The aim of this study is to evaluate the usefulness of using edible sesame oils for oral hygiene management.

Settings and Design

This study evaluates an oral hygiene management method using two types of sesame oils in elderly hospitalised patients resistant to oral hygiene management.

Methods and Material

The inpatients received oral care for 90 days. In the intervention groups, nurses brushed and wiped the oral cavity with roasted sesame oil (RSO) or sesame salad oil, while in the control group, care with tap water alone and brushing were done. Bacteria and Candida counts from tongue swabs, water content from the tongue's surface and cheek mucosa, oral health assessment tool (OHAT) and cytology of the cheek mucosa were assessed every 30 days before and after the intervention.

Results

RSO showed a tendency to reduce the number of bacteria and Candida. There was an improvement in the OHAT scores with both oils. The water content or cytology was not changing.

Conclusions

Sesame oils may improve oral hygiene and maintain health in older patients.

The Hydration Status of Adult Patients with Oropharyngeal Dysphagia and the Effect of Thickened Fluid Therapy on Fluid Intake and Hydration: Results of Two Parallel Systematic and Scoping Reviews

BACKGROUND

The effect of oropharyngeal dysphagia (OD) and thickened fluid (TF) therapy on hydration status has not been well defined in the literature. We aimed to assess the hydration status in patients with OD and the effect TF therapy has on it.

METHODS

Two literature reviews following PRISMA methodology (each one including a systematic and a scoping review) were performed: (R1) hydration status in adult patients with OD; (R2) effect of TF therapy on fluid intake and dehydration. Narrative and descriptive methods summarized both reviews. Quality assessment was assessed by Joanna Briggs Institute tools and GRADE.

RESULTS

(R1) Five out of twenty-two studies using analytical parameters or bioimpedance showed poorer hydration status among OD and 19-100% prevalence of dehydration; (R2) two high quality studies (total of 724 participants) showed positive effects of TF on hydration status. Among the articles included, nine out of ten studies that evaluated fluid intake reported a reduced TF intake below basal water requirements.

CONCLUSIONS

Dehydration is a highly prevalent complication in OD. There is scientific evidence on the positive effect of TF therapy on the hydration status of patients with OD. However, strict monitoring of fluid volume intake is essential due to the low consumption of TF in these patients.

Rice congee as an alternative to thickened liquids for patients with swallowing disorders

OBJECTIVES

Seeing the popularity of rice congee consumption among Asian families, the present study examined the possibility of preparing thickened liquids from rice congee of different consistency levels that are commonly prescribed for individuals with swallowing disorders.

METHODS

The two most common rice varieties in Hong Kong, indica and japonica rice grains, were used to prepare rice congee from which thickened liquids were extracted. By varying the water-to-rice ratio, cooking time, optional reheating on a frying pan, and temperature, slightly thick, mildly thick, moderately thick, and extremely thick liquids were obtained.

RESULTS

Recipes for extracting thickened liquids of different consistencies from rice congee cooked with indica and japonica rice grains were established. The consistency levels were defined with reference to although not strictly following the International Dysphagia Diet Standardization Initiative (IDDSI) framework. Results revealed that the consistency of the product varied with water-to-rice ratio, cooking time and temperature.

CONCLUSION

Recipes were established for preparing thickened liquids using rice grains at both serving and room temperatures. Findings support that thickened liquids so obtained can be used as an alternative to thickened liquids preparing using commercial thickeners.

Visual Modeling: A Socialization-Based Intervention to Improve Nutritional Intake Among Nursing Home Residents

Purpose Malnutrition is a widespread, dangerous, and costly condition among institutionalized older adults and can be both a contributor to and consequence of dysphagia for individuals with cognitive impairment. However, interventions to maximize intake in individuals with dementia are limited and frequently problematic, with negative implications for independence and quality of life. The goal of this study was to examine a novel, socialization-grounded intervention based on visual modeling, utilizing the theoretical underpinnings of motor resonance and mimicry. Method To examine the impact of environment on intake, data were collected from four nursing home residents (M _age = 83.5 years, SD = 4.2; three women) with dementia. Weight of food and liquid intake was measured across 15 meals and three different mealtime conditions: the "baseline condition" in which the individual ate alone, the "watch condition" in which the individual ate in the company of a "mealtime buddy," and the "eat" condition in which the individual consumed a meal while the "mealtime buddy" did the same. Results Data visualization supported a weak functional relation between eating environment and amount of intake consumed across participants. Log response ratio estimates suggested a trend for increased weight of food consumed during the eat condition as compared to baseline and the eat condition as compared to the watch condition for some participants. Conclusions These results preliminarily support the benefit of a visual model for increased consumption in some individuals with dementia. The presence and magnitude of the effect across conditions varied based on individual-level factors, such as cognitive status, which has implications for implementation. Overall, this study provides initial proof of concept regarding the use of visual modeling as an intervention approach, laying the foundation for larger scale future studies.

The Value of Blood Urea Nitrogen in the Prediction of Risks of Cardiovascular Disease in an Older Population

Background: High blood urea nitrogen (BUN) is associated with adverse outcomes in patients with cardiac disease risks. However, no study has explored whether BUN can predict the risk of cardiovascular disease (CVD) in the healthy older population. This study aims to explore the incidence and risk factors of CVD among a healthy older population community in China.

Design and Methods: This study was designed as a cohort study with a 4-year follow-up. We recruited 5,000 older people among 137,625 residents of the Gaohang community. In the baseline, subjects were asked to participate in medical screening and biological tests, and answered survey questions. During the follow-up period (2014–2017), the researchers regularly tested the subjects' indicators and assessment scales. We monitored the occurrence of CVD and explored the relationship between BUN and CVD via a Cox regression analysis.

Results: During the follow-up, subjects were newly diagnosed with CVD including heart failure (HF), heart disease events, atrial fibrillation, diabetes, hypertension, metabolic syndrome, and kidney disease. The Cox regression analysis found an association between baseline BUN and incident CVD in female subjects, with higher BUN associated with increased risk of AF in females and kidney disease in both male and females. No association was found between BUN and CVD in male subjects.

Conclusions: Current results indicate that BUN is a valuable predictive biomarker of CVD. A higher BUN level (>13.51 mg/dL) is associated with an increased occurrence of HF but a decreased occurrence of diabetes and metabolic symptoms in normal older females.

Suboptimal management of hypernatraemia in acute medical admissions

BACKGROUND

Hypernatraemia arises commonly in acute general medical admissions. Affected patients have a guarded prognosis with high rates of morbidity and mortality. Age-related physiology and physical/cognitive barriers to accessing water predispose older patients to developing hypernatraemia. This study sought to perform a descriptive retrospective review of hypernatraemic patients admitted under acute general medicine teams.

METHODS

A retrospective cross-sectional study of a sample of acute medical in-patients with serum[sodium]>145 mmol/L was conducted. Patients were exclusively older(>69 years) and admitted from Nursing homes (NH)(41%) and non-NH pathways(59%). A comparison of management of NH /non-NH patients including clinical presentation, comorbidities, laboratory values, [sodium] monitoring, intravenous fluid regimes and patient outcomes was performed.

RESULTS

In total, 102 consecutive patients (males, n=69(67.6%)) were included. Dementia and reduced mobility were more common in NH residents and admission serum [Sodium] higher (148 vs 142 mmol/L/p=0.003). Monitoring was inadequate: no routine bloods within the first 12h in >80% of patients in both groups. No patient had calculated free water deficit documented. More NH patients received correct fluid management (60% vs 33%/p%0.015). Incorrect fluid regimes occurred in both groups (38% vs 58%/p=0.070). Length of stay in discharged patients was lower in NH, (8(4-20) vs 20.5(9.8-49.3 days)/p=0.003). Time to death for NH residents was shorter (9(5.5-11.5) vs 16 (10.25-23.5) days/p=0.011).

CONCLUSION

This study highlights suboptimal management of hypernatraemia. Implementation of hypernatraemia guidelines for general medical older inpatients are clearly required with mechanisms to confirm adherence. Health care workers require further education on diagnostic challenges of dehydration in older people and the importance of maintaining adequate hydration.

Fluid Needs in the Older Adult Receiving Tube Feedings

Fluid imbalance can occur quickly in older adults and in others who cannot express thirst or are in a setting where fluid status is not closely monitored. In tube-fed individuals receiving inadequate calories, severe malnutrition may occur in weeks to months, but improper water intake may lead to critical fluid imbalances in a matter of days. Simplistic equations frequently used to determine fluid needs in adults include milliliters per kilogram of body weight and milliliters per energy (kilocalories) consumed or per energy (kilocalories) need and variations of the Holliday-Segar formula. None of these fluid-requirement equations have been validated through evidenced-based science, and research investigations have revealed that they can grossly overestimate or underestimate fluid needs in the older adult. Clinicians need guidance to better estimate initial fluid needs for the older adult receiving tube feedings and to provide proper close monitoring afterward to avert preventable fluid imbalance-related hospital readmissions, morbidities, and mortalities in this patient population.

Tear Osmolarity in the Diagnosis of Systemic Dehydration and Dry Eye Disease

Systemic dehydration due to inadequate water intake or excessive water loss, is common in the elderly and results in a high morbidity and significant mortality. Diagnosis is often overlooked and there is a need for a simple, bedside diagnostic test in at-risk populations. Body hydration is highly regulated with plasma osmolality (pOsm) being tightly controlled over a wide range of physiological conditions. By contrast, normal tear osmolarity (tOsm) is more variable since the tear film is exposed to evaporation from the open eye. While plasma hyperosmolality is a diagnostic feature of systemic dehydration, tear hyperosmolality, with other clinical features, is diagnostic of dry eye. Studies in young adults subjected to exercise and water-deprivation, have shown that tOsm may provide an index of pOsm, with the inference that it may provide a simple measure to diagnose systemic dehydration. However, since the prevalence of both dry eye and systemic dehydration increases with age, the finding of a raised tOsm in the elderly could imply the presence of either condition. This diagnostic difficulty can be overcome by measuring tear osmolality after a period of evaporative suppression (e.g., a 45 min period of lid closure) which drives tOsm osmolality down to a basal level, close to that of the pOsm. The arguments supporting the use of this basal tear osmolarity (BTO) in the diagnosis of systemic dehydration are reviewed here. Further studies are needed to confirm that the BTO can act as a surrogate for pOsm in both normally hydrated subjects and in patients with systemic dehydration and to determine the minimum period of lid closure required for a simple, "point-of-care" test.

Tough Pill to Swallow: Postextubation Dysphagia and Nutrition Impact in the Intensive Care Unit

More than 5 million patients are admitted to US intensive care units (ICUs) each year. Many of these patients have risk factors for dysphagia. Dysphagia must be promptly addressed and appropriately treated to avoid the deleterious impacts of aspiration and malnutrition. Therefore, clinicians must be aware of ways to identify and treat dysphagia. This review will highlight the risk factors, mechanisms, and impact of dysphagia in the ICU as well as provide screening, diagnostic, and management options.

Chronic Dehydration in Nursing Home Residents

Chronic dehydration mainly occurs due to insufficient fluid intake over a lengthy period of time, and nursing home residents are thought to be at high risk for chronic dehydration. However, few studies have investigated chronic dehydration, and new diagnostic methods are needed. Therefore, in this study, we aimed to identify risk factors for chronic dehydration by measuring serum osmolality in nursing home residents and also to evaluate whether examining the inferior vena cava (IVC) and determining the IVC collapsibility index (IVC-CI) by ultrasound can be helpful in the diagnosis of chronic dehydration. A total of 108 Japanese nursing home residents aged ≥65 years were recruited. IVC measurement was performed using a portable handheld ultrasound device. Fifteen residents (16.9%) were classified as having chronic dehydration (serum osmolality ≥295 mOsm/kg). Multivariate logistic regression analysis showed that chronic dehydration was associated with dementia (odds ratio (OR), 6.290; 95% confidential interval (CI), 1.270–31.154) and higher BMI (OR, 1.471; 95% CI, 1.105–1.958) but not with IVC or IVC-CI. Cognitive function and body weight of residents should be considered when establishing a strategy for preventing chronic dehydration in nursing homes.

Predictors of Residue and Airway Invasion in Parkinson's Disease

Dysphagia is a highly prevalent disorder in Parkinson's Disease (PD) characterized by changes in swallowing kinematics, residue, and airway invasion. These changes can lead to serious medical morbidities including malnutrition, aspiration pneumonia, and death. However, little is known about the most predictive causes of residue and airway invasion in this patient population. Therefore, the aims of this study were to (1) assess how disease severity affects residue, airway invasion, and swallowing kinematics in PD; and (2) determine which swallowing kinematic variables were most predictive of residue and airway invasion. A secondary analysis of forty videofluoroscopic swallow studies (VFSS) from individuals with early through mid-stage PD was performed. Airway invasion (Penetration-Aspiration Scale 'PAS'), residue (Bolus Clearance Ratio 'BCR'), and ten spatiotemporal swallowing kinematic variables were analyzed. Statistical analyses were used to determine if disease severity predicted residue, depth of airway invasion, and swallowing kinematics, and to examine which swallowing kinematic variables were most predictive of residue and the presence of airway invasion. Results revealed that residue and the presence of airway invasion were significantly predicted by swallowing kinematics. Specifically, airway invasion was primarily influenced by the extent and timing of airway closure, while residue was primarily influenced by pharyngeal constriction. However, disease severity did not significantly predict changes to swallowing kinematics, extent of residue, or depth of airway invasion during VFSS assessment. This study comprehensively examined the pathophysiology underlying dysphagia in people with early to mid-stage PD. The results of the present study indicate that disease severity alone does not predict swallowing changes in PD, and therefore may not be the best factor to identify risk for dysphagia in PD. However, the swallowing kinematics most predictive of residue and the presence of airway invasion were identified. These findings may help to guide the selection of more effective therapy approaches for improving swallowing safety and efficiency in people with early to mid-stage PD.

Management of Dehydration in Patients Suffering Swallowing Difficulties

Swallowing difficulties, also called dysphagia, can have various causes and may occur at many points in the swallowing process. The treatment and rehabilitation of dysphagia represent a major interdisciplinary and multiprofessional challenge. In dysphagic patients, dehydration is frequent and often accelerated as a result of limited fluid intake. This condition results from loss of water from the intracellular space, disturbing the normal levels of electrolytes and fluid interfering with metabolic processes and body functions. Dehydration is associated with increased morbidity and mortality rates. Dysphagic patients at risk of dehydration thus require close monitoring of their hydration state, and existing imbalances should be addressed quickly. This review gives an overview on dehydration, as well as its pathophysiology, risk factors, and clinical signs/symptoms in general. Available management strategies of dehydration are presented for oral, enteral, and parenteral fluid replacement.

Should the Energy Contribution of Commercial Thickeners Be Considered in the Nutrition Plan of Patients With Dysphagia?

BACKGROUND

Clinical management options for dysphagia include the use of thickeners to increase the consistency of liquids. Health professionals may not be aware of the nutrition value of these products, since there are no such recommendation in clinical guidelines. Our aim was to estimate the added nutrition value of the 2 types of commercial thickeners (starch and xanthan gum) to daily nutrition intake and compare their nutrition value for nectar, honey, and pudding consistencies. Additionally, we compared the nutrition value of both thickeners with a high-energy powder, since they share the same main ingredients.

METHODS

We collected recommended dosages for obtaining the 3 different consistencies and nutrition content from the technical food labels. Daily intake of fluids was estimated from the Portuguese National Food, Nutrition and Physical Activity Survey. Total daily amount of thickener needed was estimated, as well as their correspondent nutrition contributions.

RESULTS

Estimated daily fluid intake was 2439 mL. Starch thickeners provide significantly more energy at all consistencies than xanthan gum provides (423-846 kcal, P < 0.05, and 103-308 kcal, P < 0.05, respectively). Significantly more fiber is provided by xanthan gum thickeners (9 g in nectar and 27 g in pudding consistencies, P < 0.05). Median energy and carbohydrate values per 100 g of high-energy powder modules and starch thickeners are similar.

CONCLUSION

The nutrition value of thickeners should be routinely considered in the nutrition assessment and planning of patients with dysphagia for liquids, since they contribute significantly with energy, carbohydrate, and fiber.

Involvement of the epithelial sodium channel in initiation of mechanically evoked swallows in anaesthetized rats

KEY POINTS

Afferents carried by the superior laryngeal nerve play a primary role in the initiation of laryngeal mechanically evoked swallows in anaesthetized rats. Amiloride and its analogues inhibit swallowing evoked by mechanical stimulation, but not swallowing evoked by chemical and electrical stimulation. The epithelial sodium channel is probably involved in the initiation of laryngeal mechanically evoked swallows.

ABSTRACT

The swallowing reflex plays a critical role in airway protection. Because impaired laryngeal mechanosensation is associated with food bolus aspiration, it is important to know how the laryngeal sensory system regulates swallowing initiation. This study was performed to clarify the neuronal mechanism of mechanically evoked swallows. Urethane-anaesthetized Sprague-Dawley male rats were used. A swallow was identified by activation of the suprahyoid and thyrohyoid muscles on electromyography. The swallowing threshold was measured by von Frey filament and electrical stimulation of the larynx. The number of swallows induced by upper airway distension and capsaicin application (0.03 nmol, 3 μl) to the vocal folds was counted. The effects of topical application (0.3-30 nmol, 3 μl) of the epithelial sodium channel (ENaC) blocker amiloride and its analogues (benzamil and dimethylamiloride), acid-sensing ion channel (ASIC) inhibitors (mambalgine-1 and diminazene) and gadolinium to the laryngeal mucosa on swallowing initiation were evaluated. A nerve transection study indicated that afferents carried by the superior laryngeal nerve play a primary role in the initiation of laryngeal mechanically evoked swallows. The mechanical threshold of swallowing was increased in a dose-dependent manner by amiloride and its analogues and gadolinium, but not by ASIC inhibitors. The number of swallows by upper airway distension was significantly decreased by benzamil application. However, the initiation of swallows evoked by capsaicin and electrical stimulation was not affected by benzamil application. We speculate that the ENaC is involved in the initiation of laryngeal mechanically evoked swallows.

Treatment of Odontoid Type II Fractures in Octogenarians: Balancing Two Different Treatment Strategies

OBJECTIVE

Demographic changes have led to a higher incidence of C-2 fractures, especially in elderly patients. For patients with type II fractures, treatment remains controversial, as discussed by Anderson and D'Alonzo, due to the rising morbidity and mortality rates for any treatment. The aim of this study was to compare conservative and surgical management in patients with type II C-2 fractures regarding outcomes, complications, and the mortality rate.

METHODS

A retrospective analysis was performed of the medical records, X-rays, and/or computed tomography scans of patients ≥80 years of age with type II fractures who were admitted to our Department of Neurosurgery between January 1990 and December 2017. The success of treatment was evaluated 3 months after surgery.

RESULTS

In total, 125 patients were included, of whom 98 were treated surgically and 27 were treated conservatively. Surgical treatment was successful in 90.8% of cases, while conservative treatment was successful in 70.0%. The in-hospital mortality was 14.29% and the 3-month mortality was 27.8% in the surgical group, compared to 3.7% and 20% in the conservatively treated group. The in-hospital complication rate was 22.4% in the surgically treated patients and 7.4% in the conservatively treated patients.

CONCLUSION

Surgical treatment of type II fractures seemed to be associated with higher success and complication rates than conservative treatment. Nevertheless, 3-month mortality was comparable in both groups. Therefore, we conclude that surgical treatment for type II fractures in elderly patients is superior to conservative management, although conservative treatment remains a valuable option in elderly patients with severe comorbidities.

Surgical treatment improves survival of elderly with axis fracture-a national population-based multiregistry cohort study

BACKGROUND CONTEXT

Fractures of the axis (C2) are the most common cervical spinal injuries in the elderly population. Several authors have reported improved survival among elderly patients with C2 fractures when treated surgically.

PURPOSE

We aimed to analyze whether surgery improves survival of elderly with C2 fractures.

STUDY DESIGN/SETTING

An observational population-based longitudinal multi-registry study was carried out.

PATIENT SAMPLE

Swedish Patient Registry 1997 to 2014 and Swedish Cause of Death Registry 1997 to 2014 served as source of patient sample.

OUTCOME MEASURES

Survival after C2 fracture according to non-surgical and surgical treatment was the outcome measure.

METHODS

We included all patients treated for the primary diagnosis of C2 fracture (10th revision of the International Statistical Classification of Diseases and Related Health Problems or ICD-10: S12.1) at an age ≥70 years and receiving treatment at a health-care facility. Non-surgical treatment comprises cervical collar or halo-vest treatment. Surgical treatment was identified in the Swedish patient registry extract using the Swedish classification of procedural codes. Survival was determined using the Kaplan-Meier method. Comorbidity was determined using the Charlson Comorbidity Index.

RESULTS

Of the included 3,375 elderly patients with C2 fractures (43% men, aged 83±7 years), 22% were treated surgically. Surgical treatment was assigned based on age, gender, and year of treatment. The 1-year survival of 2,618 non-surgically treated patients was 72% (n=1,856), and 81% (n=614) for the 757 surgically treated (p<.001, relative risk reduction=11%). Adjusted for age, gender, comorbidity, and year of injury, surgically treated patients had greater survival than non-surgically treated patients (hazard ratio=0.88, 95% confidence interval: 0.79-0.97). Among those above 88 years of age (95% confidence interval: 85-92), surgical treatment lost its effect on survival.

CONCLUSIONS

Despite the frailty of elderly patients, the morbidity of cervical external immobilization with a rigid collar seemingly weighs greater than surgical morbidity, even in octogenarians. For those above 88 years of age, non-surgical treatment should be primarily attempted.

Use of modified diets to prevent aspiration in oropharyngeal dysphagia: is current practice justified?

BACKGROUND

Although modifying diets, by thickening liquids and modifying the texture of foods, to reduce the risk of aspiration has become central to the current management of dysphagia, the effectiveness of this intervention has been questioned. This narrative review examines, and discusses possible reasons for, the apparent discrepancy between the widespread use of modified diets in current clinical practice and the limited evidence base regarding the benefits and risks of this approach.

DISCUSSION

There is no good evidence to date that thickening liquids reduces pneumonia in dysphagia and this intervention may be associated with reduced fluid intake. Texture-modified foods may contribute to undernutrition in those with dysphagia. Modified diets worsen the quality of life of those with dysphagia, and non-compliance is common. There is substantial variability in terminology and standards for modified diets, in the recommendations of individual therapists, and in the consistency of diets prepared by healthcare staff for consumption. Although use of modified diets might appear to have a rational pathophysiological basis in dysphagia, the relationship between aspiration and pneumonia is not clear-cut. Clinical experience may be a more important determinant of everyday practice than research evidence and patient preferences. There are situations in the management of dysphagia where common sense and the necessity of intervention will clearly outweigh any lack of evidence or when application of evidence-based principles can enable good decision making despite the absence of robust evidence. Nevertheless, there is a significant discrepancy between the paucity of the evidence base supporting use of modified diets and the beliefs and practices of practitioners.

CONCLUSION

The disconnect between the limited evidence base and the widespread use of modified diets suggests the need for more careful consideration as to when modified diets might be recommended to patients. Patients (or their representatives) have a choice whether or not to accept a modified diet and must receive adequate information, about the potential risks and impact on quality of life as well as the possible benefits, to make that choice. There is an urgent need for better quality evidence regarding this intervention.

Use of Textured Thin Liquids in Patients With Dysphagia

PURPOSE

The goals of this article are to explore the use of textured thin liquids for dysphagic patients who require thickened liquids and to illustrate their impact on hydration and patient satisfaction.

METHOD

A retrospective evaluation of textured thin liquids was completed using patient data looking at laboratory values relevant to the detection of dehydration (blood urea nitrogen, creatinine, sodium) and patient satisfaction (using a clinician-generated questionnaire) on different modified liquid textures. In addition, the viscosity for all liquids was tested using a rheometer.

RESULTS

Measurements show that the viscosity of the textured thin liquids examined in this pilot study are significantly lower than the viscosity of nectar-thick liquids and fall within the "thin" category as defined by the National Dysphagia Diet guidelines. Patients on honey- and nectar-thick liquids had laboratory values signifying dehydration, whereas those receiving the textured thin liquid consistency were within the normal range for all laboratory values. Importantly, when consuming textured thin liquids, patients reported significant improvement in their satisfaction related to their thirst.

CONCLUSION

The results of this pilot study highlight the consequences of common thickened liquid dietary recommendations and of the potentially beneficial clinical application of textured thin liquids for patients with dysphagia as well as the need for future prospective research.

Basal Tear Osmolarity as a metric to estimate body hydration and dry eye severity

The osmolarities of various bodily fluids, including tears, saliva and urine, have been used as indices of plasma osmolality, a measure of body hydration, while tear osmolarity is used routinely in dry eye diagnosis, the degree of tear hyperosmolarity providing an index of disease severity. Systemic dehydration, due to inadequate water intake or excessive water loss is common in the elderly population, has a high morbidity and may cause loss of life. Its diagnosis is often overlooked and there is a need to develop a simple, bedside test to detect dehydration in this population. We hypothesize that, in the absence of tear evaporation and with continued secretion, mixing and drainage of tears, tear osmolarity falls to a basal level that is closer to that of the plasma than that of a tear sample taken in open eye conditions. We term this value the Basal Tear Osmolarity (BTO) and propose that it may be measured in tear samples immediately after a period of evaporative suppression. This value will be particular to an individual and since plasma osmolarity is controlled within narrow limits, it is predicted that it will be stable and have a small variance. It is proposed that the BTO, measured immediately after a defined period of eye closure, can provide a new metric in the diagnosis of systemic dehydration and a yardstick against which to gauge the severity of dry eye disease.

Involvement of hypoglossal and recurrent laryngeal nerves on swallowing pressure

Swallowing pressure generation is important to ensure safe transport of an ingested bolus without aspiration or leaving residue in the pharynx. To clarify the mechanism, we measured swallowing pressure at the oropharynx (OP), upper esophageal sphincter (UES), and cervical esophagus (CE) using a specially designed manometric catheter in anesthetized rats. A swallow, evoked by punctate mechanical stimulation to the larynx, was identified by recording activation of the suprahyoid and thyrohyoid muscles using electromyography (EMG). Areas under the curve of the swallowing pressure at the OP, UES, and CE from two trials indicated high intrasubject reproducibility. Effects of transecting the hypoglossal nerve (12N) and recurrent laryngeal nerve (RLN) on swallowing were investigated. Following bilateral hypoglossal nerve transection (Bi-12Nx), OP pressure was significantly decreased, and time intervals between peaks of thyrohyoid EMG bursts and OP pressure were significantly shorter. Decreased OP pressure and shortened times between peaks of thyrohyoid EMG bursts and OP pressure following Bi-12Nx were significantly increased and longer, respectively, after covering the hard and soft palates with acrylic material. UES pressure was significantly decreased after bilateral RLN transection compared with that before transection. These results suggest that the 12N and RLN play crucial roles in OP and UES pressure during swallowing, respectively. We speculate that covering the palates with a palatal augmentation prosthesis may reverse the reduced swallowing pressure in patients with 12N or tongue damage by the changes of the sensory information and of the contact between the tongue and a palates. NEW & NOTEWORTHY Hypoglossal nerve transection reduced swallowing pressure at the oropharynx. Covering the hard and soft palates with acrylic material may reverse the reduced swallowing function caused by hypoglossal nerve damage. Recurrent laryngeal nerve transection reduced upper esophageal sphincter negative pressure during swallowing.

Elevated Blood Urea Nitrogen/Creatinine Ratio Is Associated with Venous Thromboembolism in Patients with Acute Ischemic Stroke

Objective

Although venous thromboembolism (VTE) is frequently related to dehydration, the impact of dehydration on VTE in acute ischemic stroke (AIS) is not clear. This study investigated whether dehydration, as measured by blood urea nitrogen (BUN)/creatinine (Cr) ratio, influences the occurrence of VTE in patients with AIS.

Methods

This is a retrospective study of patients with AIS between January 2012 and December 2013. Patients with newly diagnosed AIS who experienced prolonged hospitalization for at least 4 weeks were included in this study.

Results

Of 182 patients included in this study, 17 (9.3%) suffered VTE during the follow-up period; in two cases, VTE was accompanied by deep vein thrombosis and pulmonary embolism. Patients with VTE were more frequently female and had higher National Institutes of Health Stroke Scale (NIHSS) score, more lower limb weakness, and elevated blood urea nitrogen BUN/Cr ratio on admission. In a multivariate analysis, BUN/Cr ratio >15 (odds ratio [OR] 8.75) and severe lower limb weakness (OR 4.38) were independent risk factors for VTE.

Conclusion

Dehydration on admission in cases of AIS might be a significant independent risk factor for VTE.

Indicators of Dysphagia in Aged Care Facilities

PURPOSE

The current cross-sectional study aimed to investigate risk factors for dysphagia in elderly individuals in aged care facilities.

METHOD

A total of 878 individuals from 42 aged care facilities were recruited for this study. The dependent outcome was speech therapist-determined swallowing function. Independent factors were Eating Assessment Tool score, oral motor assessment score, Mini-Mental State Examination, medical history, and various functional status ratings. Binomial logistic regression was used to identify independent variables associated with dysphagia in this cohort.

RESULTS

Two statistical models were constructed. Model 1 used variables from case files without the need for hands-on assessment, and Model 2 used variables that could be obtained from hands-on assessment. Variables positively associated with dysphagia identified in Model 1 were male gender, total dependence for activities of daily living, need for feeding assistance, mobility, requiring assistance walking or using a wheelchair, and history of pneumonia. Variables positively associated with dysphagia identified in Model 2 were Mini-Mental State Examination score, edentulousness, and oral motor assessments score.

CONCLUSIONS

Cognitive function, dentition, and oral motor function are significant indicators associated with the presence of swallowing in the elderly. When assessing the frail elderly, case file information can help clinicians identify frail elderly individuals who may be suffering from dysphagia.

Traumatic cervical spinal cord injury: a prospective clinical study of laryngeal penetration and aspiration

STUDY DESIGN

Prospective cohort study.

OBJECTIVES

Dysphagia is a relatively common secondary complication in patients with traumatic cervical spinal cord injuries (TCSCI). The purpose of this study was to determine the incidence of aspiration and penetration in patients with acute TCSCI.

SETTING

Tampere University Hospital, Tampere, Finland.

METHODS

A total of 46 patients with TCSCI were evaluated with a videofluoroscopic swallowing study (VFSS). Rosenbek's penetration-aspiration scale (PAS) was used to classify the degree of penetration or aspiration. The medical records of each patient were systematically reviewed.

RESULTS

Of the 46 patients, 85% were male. The mean age at the time of the injury was 62.1 years. Most patients had an incomplete injury (78%), and most of them due to a fall (78%). In the VFSS 19 (41%) patients penetrated and 15 (33%) aspirated. Only 12 (26%) of the patients had a PAS score of 1 indicating that swallowed material did not enter the airway. Of the patients who aspirated, 73% had silent aspiration.

CONCLUSION

The incidence of penetration or aspiration according to VFSS is high in this cohort of patients with TCSCI. Therefore, the swallowing function of patients with acute TCSCI should be routinely evaluated before initiating oral feeding. VFSS is highly recommended, particularly to rule out the possibility of silent aspiration and to achieve information on safe nutrition consistency.

Goal-Directed Drinking Behaviors Can Be Modified Through Behavioral Mimicry

PURPOSE

This study tested whether behavioral mimicry can alter drinking behavior. It was hypothesized that participants would increase drinking behaviors given increased confederate drinking but not cup touching.

METHODS

Nineteen healthy adults (Mage = 20.32 years) completed 2 picture description tasks; during 1 task, a confederate frequently sipped water (complete drinking gesture), and during the other, the confederate touched her cup but did not drink (partial gesture). Outcome measures included number of drinks per minute, number of cup touches per minute, percentage of time spent drinking, and percentage of time spent touching the cup.

RESULTS

Participants spent more time drinking and had an increased drinking rate during the drinking condition versus the cup-touching condition. For a majority of participants, drinking rate increased during the drinking condition versus baseline. Drinking, but not cup touching, rate also increased given increased confederate cup touching for many.

CONCLUSIONS

Mimicry likely contributes to social modeling of drinking behaviors. This effect appears more robust given a complete target gesture (full drink); however, a partial goal-directed drinking gesture may also yield a mimicked response. Beyond the theoretical implications, these results provide directions for research investigating more naturalistic mechanisms for increasing dietary intake in various patient populations (e.g., individuals with dysphagia).

Central inhibition of initiation of swallowing by systemic administration of diazepam and baclofen in anaesthetized rats

Dysphagia is caused not only by neurological and/or structural damage but also by medication. We hypothesized memantine, dextromethorphan, diazepam, and baclofen, all commonly used drugs with central sites of action, may regulate swallowing function. Swallows were evoked by upper airway (UA)/pharyngeal distension, punctate mechanical stimulation using a von Frey filament, capsaicin or distilled water (DW) applied topically to the vocal folds, and electrical stimulation of a superior laryngeal nerve (SLN) in anesthetized rats and were documented by recording electromyographic activation of the suprahyoid and thyrohyoid muscles and by visualizing laryngeal elevation. The effects of intraperitoneal or topical administration of each drug on swallowing function were studied. Systemic administration of diazepam and baclofen, but not memantine or dextromethorphan, inhibited swallowing evoked by mechanical, chemical, and electrical stimulation. Both benzodiazepines and GABA_A receptor antagonists diminished the inhibitory effects of diazepam, whereas a GABA_B receptor antagonist diminished the effects of baclofen. Topically applied diazepam or baclofen had no effect on swallowing. These data indicate that diazepam and baclofen act centrally to inhibit swallowing in anesthetized rats.NEW & NOTEWORTHY Systemic administration of diazepam and baclofen, but not memantine or dextromethorphan, inhibited swallowing evoked by mechanical, chemical, and electrical stimulation. Both benzodiazepines and GABA_A receptor antagonists diminished the inhibitory effects of diazepam, whereas a GABA_B receptor antagonist diminished the effects of baclofen. Topical applied diazepam or baclofen was without effect on swallowing. Diazepam and baclofen act centrally to inhibit swallowing in anesthetized rats.

Clinical aspects of changes in water and sodium homeostasis in the elderly

The population of elderly individuals is increasing worldwide. With aging, various hormonal and kidney changes occur, both affecting water homeostasis. Aging is a risk factor for chronic kidney disease (CKD) and many features of CKD are reproduced in the aging kidney. Dehydration and hyperosmolarity can be triggered by diminished thirst perception in this population. Elderly with dementia are especially susceptible to abnormalities of their electrolyte and body water homeostasis and should be (re-)assessed for polypharmacy. Hypo- and hypernatremia can be life threatening and should be diagnosed and treated promptly, following current practice guidelines. In severe cases of acute symptomatic hyponatremia, a rapid bolus of 100 to 150 ml of intravenous 3% hypertonic saline is appropriate to avert catastrophic outcomes; for asymptomatic hyponatremia, a very gradual correction is preferred. In summary, the body sodium (Na+) balance is regulated by a complex interplay of environmental and individual factors. In this review, we attempt to provide an overview on this topic, including dehydration, hyponatremia, hypernatremia, age-related kidney changes, water and sodium balance, and age-related changes in the vasopressin and renin-angiotensin-aldosterone system.

Tube Feeding among Elder in Long-Term Care Facilities: A Systematic Review and Meta-Analysis

OBJECTIVE

The use of tube feeding for elderly patients with poor nutritional intake is a ubiquitous method of feeding. This systematic review and meta-analysis were carried out to compare nutritional benefits of enteral feeding versus oral feeding in long-term care facilities.

SETTING

Databases including the Cochrane Library, ProQuest, PubMed, EMBASE, EBSCO, Web of Science and Google Scholar through April 2014 using keywords including enteral feeding, tube feeding or oral feeding combined with long term care facilities or nursing home.

PARTICIPANTS

Eight articles, with 841 participants were included in meta-analysis and 13 articles were included in systematic review. The elderly had to live in long-term care institutions and could not be on any mechanically assisted ventilation systems or be in any type of post-operative status.

MEASUREMENTS

The three investigators extracted and appraised data using the same study design, baseline characteristics, and outcomes, independently.

RESULTS

Following a systematic review, 13 articles out of 8218 original research articles were selected for this analysis. Meta-analysis of tube-fed patients found lower levels of hemoglobin (Weighted Mean Difference (WMD -0.21g/dl; 95% CI -0.42 to -0.01; p=0.04) and creatinine (WMD -0.08g/dl; 95% CI -0.17 to 0.00, p=0.05). Moreover, the results showed that there were no benefits regarding body mass index (BMI), albumin, dietary intake of proteins, total calories and fat.

CONCLUSIONS

The results show that tube feeding does not increase patients' nutrients absorption to improve nutritional status. Instead, these results indicate that oral feeding is better regarding some nutritional biochemical parameters.

Water-loss (intracellular) dehydration assessed using urinary tests: how well do they work? Diagnostic accuracy in older people

BACKGROUND

Water-loss dehydration (hypertonic, hyperosmotic, or intracellular dehydration) is due to insufficient fluid intake and is distinct from hypovolemia due to excess fluid losses. Water-loss dehydration is associated with poor health outcomes such as disability and mortality in older people. Urine specific gravity (USG), urine color, and urine osmolality have been widely advocated for screening for dehydration in older adults.

OBJECTIVE

We assessed the diagnostic accuracy of urinary measures to screen for water-loss dehydration in older people.

DESIGN

This was a diagnostic accuracy study of people aged ≥65 y taking part in the DRIE (Dehydration Recognition In our Elders; living in long-term care) or NU-AGE (Dietary Strategies for Healthy Ageing in Europe; living in the community) studies. The reference standard was serum osmolality, and index tests included USG, urine color, urine osmolality, urine cloudiness, additional dipstick measures, ability to provide a urine sample, and the volume of a random urine sample. Minimum useful diagnostic accuracy was set at sensitivity and specificity ≥70% or a receiver operating characteristic plot area under the curve ≥0.70.

RESULTS

DRIE participants (women: 67%; mean age: 86 y; n = 162) had more limited cognitive and functional abilities than did NU-AGE participants (women: 64%; mean age: 70 y; n = 151). Nineteen percent of DRIE participants and 22% of NU-AGE participants were dehydrated (serum osmolality >300 mOsm/kg). Neither USG nor any other potential urinary tests were usefully diagnostic for water-loss dehydration.

CONCLUSIONS

Although USG, urine color, and urinary osmolality have been widely advocated for screening for dehydration in older adults, we show, in the largest study to date to our knowledge, that their diagnostic accuracy is too low to be useful, and these measures should not be used to indicate hydration status in older people (either alone or as part of a wider tranche of tests). There is a need to develop simple, inexpensive, and noninvasive tools for the assessment of dehydration in older people. The DRIE study was registered at www.researchregister.org.uk as 122273. The NU-AGE trial was registered at clinicialtrials.gov as NCT01754012.

Oropharyngeal dysphagia: manifestations and diagnosis

Swallowing disorders (dysphagia) have been recognized by the WHO as a medical disability associated with increased morbidity, mortality and costs of care. With increasing survival rates and ageing of the population, swallowing disorders and their role in causing pulmonary and nutritional pathologies are becoming exceedingly important. Over the past two decades, the study of oropharyngeal dysphagia has been approached from various disciplines with considerable progress in understanding its pathophysiology. This Review describes the most frequent manifestations of oropharyngeal dysphagia and the clinical as well as instrumental techniques that are available to diagnose patients with dysphagia. However, the clinical value of these diagnostic tests and their sensitivity to predict outcomes is limited. Despite considerable clinical research efforts, conventional diagnostic methods for oropharyngeal dysphagia have limited proven accuracy in predicting aspiration and respiratory disease. We contend that incorporation of measurable objective assessments into clinical diagnosis is needed and might be key in developing novel therapeutic strategies.

Malnutrition and Dysphagia in long-term care: a systematic review

Determining the co-occurrence of malnutrition and dysphagia is important to understand the extent to which swallowing impairment contributes to poor food intake in long-term care (LTC). This review investigated the impact of dysphagia on malnutrition in LTC by synthesizing the results of published literature. Seven electronic databases were used to search for English-language publications reporting malnutrition and dysphagia in LTC facilities from 1946 to 2013. Fourteen studies were eligible for inclusion. Overall, the literature on the co-occurrence of malnutrition and dysphagia in LTC shows a paucity of high-quality evidence. Articles reviewed lacked consistent definitions for both conditions. Methods used to confirm each diagnosis also differed and were of questionable validity. Based on a review of the literature, evidence of the existence of concurrent concerns with respect to malnutrition and dysphagia emerges. The reported frequency of participants in LTC with dysphagia ranges from 7% to 40%, while the percentage of those who were malnourished ranges from 12% to 54%. Due to discrepancies used to describe and measure these conditions, it is difficult to determine the exact prevalence of either condition separately, or in combination. Consequently, the impact of dysphagia on malnutrition must be considered and studied using valid definitions and measures.

Clinical symptoms, signs and tests for identification of impending and current water-loss dehydration in older people

BACKGROUND

There is evidence that water-loss dehydration is common in older people and associated with many causes of morbidity and mortality. However, it is unclear what clinical symptoms, signs and tests may be used to identify early dehydration in older people, so that support can be mobilised to improve hydration before health and well-being are compromised.

OBJECTIVES

To determine the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs and tests to be used as screening tests for detecting water-loss dehydration in older people by systematically reviewing studies that have measured a reference standard and at least one index test in people aged 65 years and over. Water-loss dehydration was defined primarily as including everyone with either impending or current water-loss dehydration (including all those with serum osmolality ≥ 295 mOsm/kg as being dehydrated).

SEARCH METHODS

Structured search strategies were developed for MEDLINE (OvidSP), EMBASE (OvidSP), CINAHL, LILACS, DARE and HTA databases (The Cochrane Library), and the International Clinical Trials Registry Platform (ICTRP). Reference lists of included studies and identified relevant reviews were checked. Authors of included studies were contacted for details of further studies.

SELECTION CRITERIA

Titles and abstracts were scanned and all potentially relevant studies obtained in full text. Inclusion of full text studies was assessed independently in duplicate, and disagreements resolved by a third author. We wrote to authors of all studies that appeared to have collected data on at least one reference standard and at least one index test, and in at least 10 people aged ≥ 65 years, even where no comparative analysis has been published, requesting original dataset so we could create 2 x 2 tables.

DATA COLLECTION AND ANALYSIS

Diagnostic accuracy of each test was assessed against the best available reference standard for water-loss dehydration (serum or plasma osmolality cut-off ≥ 295 mOsm/kg, serum osmolarity or weight change) within each study. For each index test study data were presented in forest plots of sensitivity and specificity. The primary target condition was water-loss dehydration (including either impending or current water-loss dehydration). Secondary target conditions were intended as current (> 300 mOsm/kg) and impending (295 to 300 mOsm/kg) water-loss dehydration, but restricted to current dehydration in the final review.We conducted bivariate random-effects meta-analyses (Stata/IC, StataCorp) for index tests where there were at least four studies and study datasets could be pooled to construct sensitivity and specificity summary estimates. We assigned the same approach for index tests with continuous outcome data for each of three pre-specified cut-off points investigated.Pre-set minimum sensitivity of a useful test was 60%, minimum specificity 75%. As pre-specifying three cut-offs for each continuous test may have led to missing a cut-off with useful sensitivity and specificity, we conducted post-hoc exploratory analyses to create receiver operating characteristic (ROC) curves where there appeared some possibility of a useful cut-off missed by the original three. These analyses enabled assessment of which tests may be worth assessing in further research. A further exploratory analysis assessed the value of combining the best two index tests where each had some individual predictive ability.

MAIN RESULTS

There were few published studies of the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs or tests to be used as screening tests for detecting water-loss dehydration in older people. Therefore, to complete this review we sought, analysed and included raw datasets that included a reference standard and an index test in people aged ≥ 65 years.We included three studies with published diagnostic accuracy data and a further 21 studies provided datasets that we analysed. We assessed 67 tests (at three cut-offs for each continuous outcome) for diagnostic accuracy of water-loss dehydration (primary target condition) and of current dehydration (secondary target condition).Only three tests showed any ability to diagnose water-loss dehydration (including both impending and current water-loss dehydration) as stand-alone tests: expressing fatigue (sensitivity 0.71 (95% CI 0.29 to 0.96), specificity 0.75 (95% CI 0.63 to 0.85), in one study with 71 participants, but two additional studies had lower sensitivity); missing drinks between meals (sensitivity 1.00 (95% CI 0.59 to 1.00), specificity 0.77 (95% CI 0.64 to 0.86), in one study with 71 participants) and BIA resistance at 50 kHz (sensitivities 1.00 (95% CI 0.48 to 1.00) and 0.71 (95% CI 0.44 to 0.90) and specificities of 1.00 (95% CI 0.69 to 1.00) and 0.80 (95% CI 0.28 to 0.99) in 15 and 22 people respectively for two studies, but with sensitivities of 0.54 (95% CI 0.25 to 0.81) and 0.69 (95% CI 0.56 to 0.79) and specificities of 0.50 (95% CI 0.16 to 0.84) and 0.19 (95% CI 0.17 to 0.21) in 21 and 1947 people respectively in two other studies). In post-hoc ROC plots drinks intake, urine osmolality and axillial moisture also showed limited diagnostic accuracy. No test was consistently useful in more than one study.Combining two tests so that an individual both missed some drinks between meals and expressed fatigue was sensitive at 0.71 (95% CI 0.29 to 0.96) and specific at 0.92 (95% CI 0.83 to 0.97).There was sufficient evidence to suggest that several stand-alone tests often used to assess dehydration in older people (including fluid intake, urine specific gravity, urine colour, urine volume, heart rate, dry mouth, feeling thirsty and BIA assessment of intracellular water or extracellular water) are not useful, and should not be relied on individually as ways of assessing presence or absence of dehydration in older people.No tests were found consistently useful in diagnosing current water-loss dehydration.

AUTHORS' CONCLUSIONS

There is limited evidence of the diagnostic utility of any individual clinical symptom, sign or test or combination of tests to indicate water-loss dehydration in older people. Individual tests should not be used in this population to indicate dehydration; they miss a high proportion of people with dehydration, and wrongly label those who are adequately hydrated.Promising tests identified by this review need to be further assessed, as do new methods in development. Combining several tests may improve diagnostic accuracy.