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.

Association among sickle cell trait, fitness, and cardiovascular risk factors in CARDIA

“…10,13,[27][28][29][30][31] In contrast, our results do not demonstrate differences in baseline or longitudinal changes in fitness by SCT status, which is consistent with other studies that have also shown no difference in maximal oxygen uptake or key determinants of fitness, including lactate production and ventilatory threshold, in individuals with and without SCT. [32][33][34][35] We also found no difference in autonomic nervous system function by SCT status, using our measure of heart rate recovery after exercise.…”

“…[7][8][9] Growing evidence suggests SCT carriers may exhibit abnormal physiologic responses to cardiopulmonary exercise testing when compared with controls without SCT. [10][11][12][13] More recently, SCT status was also shown to be associated with a significantly higher risk for exertional rhabdomyolysis among black soldiers on active duty in the US Army.…”

“…[7][8][9] Growing evidence suggests SCT carriers may exhibit abnormal physiologic responses to cardiopulmonary exercise testing when compared with controls without SCT. [10][11][12][13] More recently, SCT status was also shown to be associated with a significantly higher risk for exertional rhabdomyolysis among black soldiers on active duty in the US Army.14 However, findings relating to the relationship between SCT status and cardiopulmonary fitness in these studies have been equivocal, in part limited by small sample sizes. Also, the effect of SCT on the development of other cardiovascular risk factors, as well as how this relationship is influenced by fitness, has not been previously examined despite growing evidence for an increased risk for chronic kidney disease in SCT carriers.…”

Coronary Artery Ectasia in Atherosclerotic Coronary Artery Disease, Inflammatory Disorders, and Sickle Cell Disease

“…Therefore, this population should be encouraged to maintain a physically active lifestyle and a moderate exercise prescription, cautiously, and gradually increased to reach goal, may be warranted. More importantly, those patients should be instructed to maintain good hydration and avoid dehydration and high ambient temperature because they can increase the risk of hyperviscosity complications in response to exercise [80,81].…”

ACSM and CHAMP Summit on Sickle Cell Trait

“…As such, several investigations have monitored these biological factors in response to exercise. To date, the main findings include the following: 1) SCT carriers at rest have increased blood viscosity (19,86,90), slightly decreased RBC deformability (19,87), somewhat inereased RBC disaggregation threshold (87), and increased plasma eoncentration of the adhesion molecule vascular cell adhesion molecule 1 (4,67,68); 2) exercise results in a greater decrease in RBC deformability in SCT carriers than that in controls during late exercise recovery (89), but adequate hydration normalizes the hemorheological abnormalities of SCT carriers (90); 3) exercise results in a greater activation of leucocytes and platelets in SCT carriers than that in non-SCT controls (88); and 4) SCT carriers and controls exhibit very few differenees in eoagulation processes (7,24,100).…”