title: Effects of hydration and dehydration on blood rheology in sickle cell trait carriers during exercise.
abstract: This study compared the hemorheological responses of a group of sickle cell trait (SCT) carriers with those of a control (Cont) group in response to 40 min of submaximal exercise (exercise intensity, 55% aerobic peak power) performed in two conditions: one with water offered ad libitum, i.e., the hydration (Hyd) condition, and one without water, i.e., the dehydration (Dehyd) condition. Blood and plasma viscosities, as well as red blood cell rigidity, were determined at rest, at the end of exercise, and at 2 h recovery with a cone plate viscometer at high shear rate and 37 degrees C. The SCT and Cont groups lost 1 +/- 0.7 and 1.6 +/- 0.6 kg of body weight, respectively, in the Dehyd condition, indicating a significant effect of water deprivation compared with the Hyd condition, in which body weight remained unchanged. Plasma viscosity increased with exercise and returned to baseline during recovery independently of the group and condition. As previously demonstrated, resting blood viscosity was greater in the SCT carriers than in the Cont group. Blood viscosity increased by the end of exercise and returned to baseline at 2 h recovery in the Cont group in both conditions. The blood viscosity of SCT carriers did not change in response to exercise in the Dehyd condition and remained elevated at 2 h recovery. This extended hyperviscosity, in association with other biological changes induced by exercise, could be considered as a risk factor for exercise-related events in SCT carriers, similar to vasoocclusive crises, notably during the recovery. In contrast, the Hyd condition normalized the hyperviscosity and red blood cell rigidity of the SCT carriers, with blood viscosity values reaching the same lower values as those found in the Cont group during the recovery. Adequate hydration of SCT carriers should be strongly promoted to reduce the clinical risk associated with potential hyperviscosity complications.
authors.affiliation: Laboratoire Acclimation au Climat Tropical, Exercice et Santé (EA 3596), Département de Physiologie, Université des Antilles et de Guyane, Pointe-à-Pitre, Guadeloupe.
authors.forename: Julien
authors.initials: J
authors.lastname: Tripette
authors.forename: Gylna
authors.initials: G
authors.lastname: Loko
authors.forename: Abdoulaye
authors.initials: A
authors.lastname: Samb
authors.forename: Bertin Doubi
authors.initials: BD
authors.lastname: Gogh
authors.forename: Estelle
authors.initials: E
authors.lastname: Sewade
authors.forename: Djibril
authors.initials: D
authors.lastname: Seck
authors.forename: Olivier
authors.initials: O
authors.lastname: Hue
authors.forename: Marc
authors.initials: M
authors.lastname: Romana
authors.forename: Saliou
authors.initials: S
authors.lastname: Diop
authors.forename: Mor
authors.initials: M
authors.lastname: Diaw
authors.forename: Karine
authors.initials: K
authors.lastname: Brudey
authors.forename: Pascal
authors.initials: P
authors.lastname: Bogui
authors.forename: Fallou
authors.initials: F
authors.lastname: Cissé
authors.forename: Marie-Dominique
authors.initials: MD
authors.lastname: Hardy-Dessources
authors.forename: Philippe
authors.initials: P
authors.lastname: Connes
mesh_terms: D001809:Blood Viscosity / Q000502:physiology; D003681:Dehydration / Q000097:blood* / Q000503:physiopathology; D015444:Exercise / Q000502:physiology*; D005260:Female; D018056:Hemorheology / Q000502:physiology*; D006801:Humans; D008297:Male; D012805:Sickle Cell Trait / Q000097:blood* / Q000503:physiopathology