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Aim: Higher winter mortality in elderly has been associated with augmented systolic blood pressure (SBP) response and with impaired defense of core temperature. Here we investigated whether the augmented SBP upon mild cold exposure remains after a rewarming period, and whether SBP changes are linked to thermoregulation. Therefore, we tested the following hypotheses: cold-induced increase in SBP a) remains augmented after rewarming in elderly compared to young adults b) is related to non-shivering thermogenesis upon mild cold c) is related to vasoconstriction upon mild cold. Methods: BP, energy expenditure (EE), skin and core temperature, skin perfusion (abdomen, forearm, both sides of hand) and % body fat were measured in 12 young adults (Y) and 12 elderly (E). Supine subjects were exposed to a thermoneutral baseline 0.5h (T(air) =30.1 degrees C), 1h mild cold (T(air) =20.7 degrees C), 1h rewarming (T(air) =34.8 degrees C) and 1h baseline (T(air) =30.5 degrees C). Results: Upon mild cold only the young adults showed significant non-shivering thermogenesis (NST) (Y:+2.5+/-0.6W/m(2) ,p |
