Could very hot weather or recent surgery/general anaesthetic affect a fingerprick home blood test?

[TaraJR]

I sent a T4/T3/TSH fingerprick test back to Medichecks. It was the very hot week in early September... 29C degrees here in Norfolk. Medichecks received it the next day. Test done per our recommended conditions. Results were:

T4 19.0 (12 - 22)

T3 6.1 (3.1 - 6.8)

TSH 0.008 (0.27 - 4.2)

My T4 and T3 are consistently less than this (approx t5 15, T3 4.8, and TSH 0.01)

I'd also had a 3 hour general anaesthetic for feet surgery 4 weeks before, and was very inactive (had my feet elevated for 23 hours a day!)

Does anyone know if either very hot weather or a general anaesthetic/surgery can affect results?

Thanks!

[HealthStarDust]

Temperature of the testing or sample environment probably does.

[Lalatoot]

Your life was not as normal for you so it could be expected that your results might not be.It was hotter than normal so you weren't using hormones to heat your body

You were inactive so again hormones were not being used in the buzz of daily life .

Your body was in recovery mode and was healing so it's resources were focused on that .

I'd retest in 6 weeks.

[Anthea55 in reply to Lalatoot]

Dr Peatfield recommended reducing your thyroid meds when the weather is hot and / or you are inactive. I remembered that during the recent hot spell - definitely helped.

[SlowDragon Administrator]

also aesthetic can drastically reduce B12

What vitamin supplements do you take

[Lily905]

I had all of my thyroid removed in 2008 & I've noticed when the weather (UK) is either Very cold or Very hot the changes are always noticed in my blood test results - the GP always accepts my explanation that the extremes in weather are reflected in my blood. Since I've had my thyroid removed I now find it very difficult to cope with extremely hot or cold weather.