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Long COVID is wrecking our IQs

This effect may or may not be permanent, but a team of researchers in England has found that long COVID significantly reduces cognitive ability—and the longer the COVID the more it hurts:

Six IQ points is no joke, though this loss is found only in the most extreme cases. On the other hand, these are averages, which means a significant fraction of even the less severe cases are seeing cognitive declines of 4-5 IQ points.

For the most severe cases, which required ICU admission, IQ declines were 9 points or more, with a few cases showing declines of 20-30 points.

This effect on cognition was highest with the original COVID strain and has waned with the more recent variants. Vaccination helps a little bit. The worst effects were on short-term memory and verbal accuracy, while the mildest effects were on spatial planning.

33 thoughts on “Long COVID is wrecking our IQs

  1. D_Ohrk_E1

    And the risk of PASC increases the more times you are infected. But hey, y'all folks without masks you go on and live your fullest life, yeah?

    As they (Jesus) say, the meek shall inherit the Earth.

        1. MattBallAZ

          Yes, me too re: masks.
          Doesn't this explain a lot about supporters of TFG and why the right-wing wants more infections?
          Not joking.

          1. realrobmac

            I'm not joking either. I haven't worn a mask at all since early 2023 and only intermittently wore one after my initial vaccination in 2021. I did get covid in 2022 but it was mild and I felt no long term effects.

            The night is dark and full of terrors I know but IMO there are much greater things to fear out there at this point than COVID.

            Very few people, right wing or not, are regularly masking at this point, so this is not a political thing.

            1. D_Ohrk_E1

              Cost of compliance < Cost of long-COVID treatment

              Seems to me, everyone who has gotten Long-COVID has expressed regret for not taking the simple, inexpensive step of compliance.

              1. bmore

                I agree. I'm not masking much, but I avoid indoor events with more than a few people, or in crowded spaces. A family member was vaxxed, masked, but worked in health care field, and has long covid. They have had extensive neuropathy for almost 2 years now. I have a lot of respect for covid.

            2. MattBallAZ

              I 100% do not understand the aversion to masking. It is really not a big deal at all. How is it in any way worst than having covid once a year?
              Sorry - I'm truly baffled.

      1. iamr4man

        Yes, also have had all of the vaccines, also have avoided most crowded events. I don’t mask outdoors but my nephew’s wife caught it at a crowded outdoor event. I’m 71. I might feel differently if I was younger. My adult children almost never mask.

    1. D_Ohrk_E1

      Hope springs eternal.

      But the mechanism of this neurological problem is inflammation in the brain. You know what else is marked (literally, by bio-markers) by inflammation? Alzheimer's, Dementia, and CTE, aka traumatic brain injury.

      1. golack

        They're seeing evidence of a leaky blood-brain barrier. If that holds, there are treatments available--then we'll have to see if those treatments work. It also means a blood test could be available to diagnose long covid.

        1. D_Ohrk_E1

          Well, if you're of the mindset that the amyloid beta plaque is the cause of ALZ and the class of drugs which remove said plaque is the solution, then sure, the blood-brain barrier can be breached and therefore, an effective treatment should be found one day.

          My personal theory is that stopping cognitive decline (from such diseases and effects of inflammation) has more to do with epigenetic changes to the immune system caused by infections.

          1. golack

            Different issues with immune system. It could be hyperactive, therefore leads to swelling and problems. Alternatively, with Alzheimer's, it might not be active enough and the plaques are just an innate immune response to keep things in check until the antibodies ramp up. For the latter, there's evidence that yearly flu vaccines help prevent Alzheimer's disease and possibly the TB vaccine could help. Note: though interesting, more studies are needed to see if these hold up--so maybe in 5 or 10 years we'll know....
            see also:
            https://www.theguardian.com/society/2024/feb/22/long-covid-brain-fog-may-be-due-to-leaky-blood-brain-barrier-study
            https://www.medicalnewstoday.com/articles/bcg-vaccine-treatment-could-protect-against-alzheimers-and-other-dementias

    1. lower-case

      yup, i don't see solving any partial differential equations in my future

      but i've got 150 bottles of liquor in my 'library' and no corporate boss to answer to so life is good

  2. Altoid

    Cue the obvious jokes about how anyone could tell, but since a) "brain fog" is a known post-covid phenomenon, and b) trump had a particularly bad case back in the early days of covid and therefore with the original virus, I've been wondering for a quite a while whether his increasing confusion (like Nancy Pelosi for Nikki Haley) and higher rate of disjointed non sequiturs might be covid aftereffects. (Or maybe I'm just wish-casting for poetic justice, or something.)

    1. Jasper_in_Boston

      I'd be shocked if a man with his BMI doesn't suffer from metabolic syndrome, but yeah, a bad case of covid wouldn't have helped.

  3. jambo

    Ironically the reverse is also true. Low cognitive ability (drinking bleach, thinking vaccines are a deep state plot) is associated with a higher likelihood of Covid.

  4. Jim Carey

    A lower IQ is to life what a slower car is to a journey. Higher IQs and faster cars are assets if you're heading in the right direction and otherwise liabilities.

    Wisdom is to life what heading in the right direction is to a journey. Wisdom is an asset and willful ignorance (aka naivete, aka cynicism) is a liability.

    Translation: worry more about a loss of wisdom and less about a loss of IQ.

  5. Heysus

    Still masking around here and must mask up at clinics and hospitals. I have been fortunate to not have had Covid but many family members, friends, and neighbours have.
    At my age, I can’t afford to lose even one point!

  6. geordie

    The problem I have with this is I am not sure that the lowering of IQ is all that COVID specific. A cold or the flu always made me feel dumber than usual. Heck my allergies do too. Maybe being sick takes mental energy.

    I also wonder how many people had long “X” before COVID but we never acknowledged it. It certainly seems more common now but I recall people having a cold they couldn’t quite get rid of for weeks or months since forever.

    I’m not trying to downplay COVID. I just think being sick has always been terrible and with the passage of time we tend to forget that..

  7. smallteams

    From the study:

    "Longer-term persistence of cognitive deficits and any clinical implications remain uncertain."

    I mention this because I clearly suffered from brain fog while I had Covid (I was hospitalized with Delta, and had about 23 other symptoms as well ... it was bad). I had trouble controlling fine-motor movements, trouble completing easy crossword puzzles ... those were the most noticeable to me.

    I'm back to NYT Sunday puzzles, and my guitar-playing has never been better.

    My point is: when did they measure the loss? The amount of time after recovery certainly mattered in my case, and may matter quite a bit in the larger population. In other words, it might not be permanent, at least permanent to the measured degree.

    1. smallteams

      If any typos remain in my post, it's not fog. It's the lack of contrast with this amber typeface when I enter comments. I can't necessarily type (never could .. I'm fast but hardly mistake-free), but I can edit if I can see the issues!

      1. emjayay

        The dark amber/burnt orange type is just a weird choice. The lack of a thumbs up (or down) feature is just frustrating. Ability to post photos or graphics would be nice particularly since Kevin is so graph and stats oriented. I've wanted to post some econ stats graph several times and then realized I couldn't.

        SHAPE UP WORDPRESS (or Kevin move to a different service).

  8. AlHaqiqa

    I just skimmed the article - so I apologize if I misread. They looked at demographic factors for comparison, but did they look at the treatments that people had for COVID? In particular, I was wondering about the impact of the ventilators. Since there was a lot more impact in the early days, and that's when ventilators were being used...

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