Hydration Marker Diagnostic Accuracy to Identify Mild Intracellular and Extracellular Dehydration.
Int J Sport Nutr Exerc Metab
; 29(6): 604-611, 2019 Nov 01.
Article
in En
| MEDLINE
| ID: mdl-31141419
ABSTRACT
Identifying mild dehydration (≤2% of body mass) is important to prevent the negative effects of more severe dehydration on human health and performance. It is unknown whether a single hydration marker can identify both mild intracellular dehydration (ID) and extracellular dehydration (ED) with adequate diagnostic accuracy (≥0.7 receiver-operating characteristic-area under the curve [ROC-AUC]). Thus, in 15 young healthy men, the authors determined the diagnostic accuracy of 15 hydration markers after three randomized 48-hr trials; euhydration (water 36 ml·kg-1·day-1), ID caused by exercise and 48 hr of fluid restriction (water 2 ml·kg-1·day-1), and ED caused by a 4-hr diuretic-induced diuresis begun at 44 hr (Furosemide 0.65 mg/kg). Body mass was maintained on euhydration, and dehydration was mild on ID and ED (1.9% [0.5%] and 2.0% [0.3%] of body mass, respectively). Urine color, urine specific gravity, plasma osmolality, saliva flow rate, saliva osmolality, heart rate variability, and dry mouth identified ID (ROC-AUC; range 0.70-0.99), and postural heart rate change identified ED (ROC-AUC 0.82). Thirst 0-9 scale (ROC-AUC 0.97 and 0.78 for ID and ED) and urine osmolality (ROC-AUC 0.99 and 0.81 for ID and ED) identified both dehydration types. However, only the thirst 0-9 scale had a common dehydration threshold (≥4; sensitivity and specificity of 100%; 87% and 71%, 87% for ID and ED). In conclusion, using a common dehydration threshold ≥4, the thirst 0-9 scale identified mild intracellular and ED with adequate diagnostic accuracy. In young healthy adults', thirst 0-9 scale is a valid and practical dehydration screening tool.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Saliva
/
Tears
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Thirst
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Urine
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Exercise
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Dehydration
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Heart Rate
Type of study:
Clinical_trials
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Diagnostic_studies
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Prognostic_studies
Limits:
Adolescent
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Adult
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Humans
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Male
Language:
En
Journal:
Int J Sport Nutr Exerc Metab
Journal subject:
CIENCIAS DA NUTRICAO
/
MEDICINA ESPORTIVA
/
METABOLISMO
Year:
2019
Document type:
Article