No effect of smoking on progression


Javizian O, Metz LM, Deighton S, Koch MW.Smoking does not influence disability accumulation in primary progressive multiple sclerosis. Eur J Neurol. 2017 Feb 26. doi: 10.1111/ene.13262. [Epub ahead of print]

BACKGROUND AND PURPOSE:The modifiable risk factor cigarette smoking has been associated with an increased risk of developing multiple sclerosis (MS) and with disease activity in relapsing-remitting MS. However, less is known about the effect of smoking on disease progression in progressive MS. Here the association between cigarette smoking and disability accumulation in primary progressive MS (PPMS) is investigated.
METHODS:Kaplan-Meier survival analyses and Cox proportional hazard modelling were used to investigate the influence of cigarette smoking on the risk of reaching Expanded Disability Status Scale (EDSS) 4 and 6 as well as the time from EDSS 4 to 6 in patients with PPMS.
RESULTS: In all, 416 patients with PPMS and available smoking history were identified. Median time to EDSS 4 was 4 years in ever-smokers and 5 years in never-smokers (P = 0.27), and it was 9 years to EDSS 6 in both ever-smokers and never-smokers (P = 0.48). Smokers were not at increased risk of faster progression to EDSS 4, 6 and from EDSS 4 to 6. Age at disease onset was the strongest risk factor for progression to EDSS 4, 6 and from EDSS 4 to 6.
CONCLUSIONS: Our investigation of a large and well-characterized population based PPMS cohort suggests that cigarette smoking does not influence disability accumulation in PPMS. Our findings support the idea that PPMS is driven by different underlying pathomechanisms than relapsing-remitting MS.

So we are generally anti-smoking but every now and again you get the contrary view. This is the smoking has no effect.

This is what was also said by others

Risk factors associated with the onset of relapsing-remitting and primary progressive multiple sclerosis: a systematic review.
McKay KA, Kwan V, Duggan T, Tremlett H. Biomed Res Int. 2015;2015:817238.

However, you can read the blog and there are plenty of papers arguing it is not good. We know it is is not good for your health or your pocket, 

However, response to smoking does not convince me that PPMS is a dissease disease to RRMS. 

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  • Hmm… remember MD2 and his salt calculation :-)? Dose-effect is everything here. "Ever smoking" could be "I smoked every now and then at parties when I was 16" or "I have been smoking 40 a day for 50 years now". And people often lie about smoking and alcohol. Even to themselves. 🙂
    The thing is: smoking is not good for the heart – that we know. What is not good for the heart is not good for the brain either – that we know. So if I am sounding like Mr Rumsfeld now lets try the other side…

    My epidemiological conundrum case: They smoke like chimneys in Japan (more than in the US) and still they have much lower prevalence of MS and RA. What protects them?

    • people often lie about smoking and alcohol. Even to themselves …

      My brother told me that at med school in the U.K. He was told to multiple how much the patient says they drink or smoke by 2 and divide the frequency of sex by 2. Is that right, my doctors here in the USA think that's not true.

    • An intersting question could be: in Austria people smoke the double than people in Finland – is there the prevalence of MS the double too? I don't know.

    • I think they are in the same range of values (high , over >100 per 100,000) in both countries, I guess the Finns should be worse off because of the north-south gradient and low sun exposure levels. I'll try to look for more specific values. 🙂
      I think Canada is currently on top of the MS prevalence mountain.

    • Yes it is higher in Austria! 140 per 100,000 in Austria and 105 per 100,000 in Finland… although this is not exact science and there may be underreporting and so on.

  • If we assume that progressive MS is MS that has used up its "cognitive reserve" then this finding is not surprising – the damage is done, the repair mechanism is not there (for whatever reason).
    Then again, as with salt and the mice… the dose-effect in smoking is also there. "Ever smokers" could be "I smoked different things at parties when I was 17, I have not seen a cigarette since" or "I smoke 40 a day and have been doing it for 50 years now".

  • Dear MD, I cannot see unrelated blogger comments for March… it is the 1st today 🙂
    I have a question: what is in ATX-MS-1467 and how did they choose the peptides? ( cannot be random stuff and things, can it? 🙂

    • ts up, thanks for reminding me.

      ATX-MS-1467 is a mix of different myelin basic protein peptides.
      These are picked so that most people are able to respond to them.

      They are then injected under the skin and your MS goes away, that is the logic.

      Hope it works, I have my thoughts on this approach. You can read them in the blog

  • I don't care about this weird study – I have PPMS and I know that if I had smoked, I would not be as well as I am today.

    Lies, damned lies, and "scientific" studies.

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