MS symptoms and heat

Epub: Leavitt VM, Sumowski JF, Chiaravalloti N, Deluca J. Warmer outdoor temperature is associated with worse cognitive status in multiple sclerosis Neurology 2012 March 7.

OBJECTIVE: Patients with multiple sclerosis (MS) have more clinical exacerbations and T2 lesion activity during warmer weather. The current study is the first to investigate whether outdoor temperature is related to cognitive status across patients with MS (cross-sectional analysis), and whether cognitive status fluctuates with changes in outdoor temperature within patients with MS (longitudinal analysis).

METHODS: For the cross-sectional analysis, 40 patients with MS and 40 healthy control (HC) subjects were recruited throughout the calendar year. Cognitive status (processing speed, memory) and outdoor temperature were recorded for the day of testing. We calculated partial correlations between cognitive status and temperature for patients with MS and HCs, controlling for demographic and disease variables. For the longitudinal analysis, cognitive status and outdoor temperature were recorded at baseline and 6-month follow-up in a separate sample of 45 patients with MS. We calculated the partial correlation between temperature and cognitive status at follow-up, controlling for baseline temperature and cognitive status (i.e., whether temperature changes are related to cognitive changes within patients with MS).

RESULTS: Cross-sectionally, warmer temperature was related to worse cognitive status in patients with MS (r(p) = -0.45, p = 0.006), not in HCs (r(p) = 0.00, p = 0.984). Longitudinally, increased outdoor temperature from baseline to follow-up was related to a decline in cognitive status within patients with MS (r(p) = -0.39, p = 0.010).

CONCLUSIONS: Cognitive status in patients with MS is worse on warmer days, consistent with a previously established link between heat and lesion activity. Our findings have implications for clinical trial planning, treatment, and lifestyle decisions. We discuss cognitive status as a potential marker of quiescent exacerbations

Temperature has been shown to influence some signs of multiple sclerosis previously. Uhthoff’s phenomenon is the worsening of neurologic symptoms in multiple sclerosis (MS) and other neurological, demyelinating conditions when the body gets overheated from hot weather, exercise, fever, or saunas and hot tubs. It is possibly due to the effect of increased temperature on nerve conduction. With an increased body temperature, nerve impulses are either blocked or slowed down in a damaged nerve but once the body temperature is normalized, signs and symptoms may disappear or improve. Therefore it may not be surprising that heat can affect MS behaviours of cognitive function similar to Uhthoffs phenomenon.

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  • Is there any risk of permanently causing further damage to my nerve cells and axons by going to a sauna or sitting in a hot tub? I get tired of these things for an hou or so but enjoy them so much that i am willing to take the fatigue.

  • Prof G would be better placed to answer this comment but I suspect that the answer is not known

    There was one study of MS and Sauna that I found

    Mult Scler. 2011 Sep 13. [Epub] The effects of heat stress on cognition in persons with multiple sclerosis. Hämäläinen P et al.
    A significant increase in core body temperature during heat stress is associated with a mild and REVERSIBLE worsening of the some tests, while visual vigilance performance seems to remain almost unaffected.

    It is better to feel life than feel it is a lifetime

  • why is it there's no mri s and ultrasounds of deep and neck veins cerebral veins and neck same day one being reg nomal and one with a heat stress to see what's happen in the brain during the corse of ms is it possible swelling accrues and continue to swell to cause progression

    • This most likely has nothing to do with CCSVI and so there is not point in looking at veins and has more to do with demyelinated nerves and how they transmit. This is afftered by temperature.

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