The presenter told her co-host Ben Shephard and Dr Hilary Jones that the virus has "undoubtedly" impacted his "brain connections to his body".
WATCH: Kate Garraway breaks down in tears after winning an NTA for Finding Derek
The trio were discussing the latest news about the coronavirus pandemic when Kate spoke about her husband ahead of the release of a new documentary, Caring For Derek, which follows Derek's return to the family home after being critically ill in hospital.
"Obviously he is still terribly affected by Covid, and undoubtedly it has had an effect on certainly brain connections to his body," she said.
Ben asked: "So not just physical wellbeing, but mental wellbeing as well?"
Kate replied: "I don't know about mental wellbeing if I'm absolutely honest because he is still so affected in terms of communication and mobility that I wouldn't feel qualified to say whether it had had an impact in terms of depression and anxiety.
Kate revealed that Derek is "still terribly affected" after contracting coronavirus in 2020
"I mean it must be I would have thought, because if you are still unable to communicate and very challenged mobility wise, and lung, and all the other things, then that is going to affect anxiety."
She continued: "It's interesting isn't it that now at last, you and I have talked about this a lot Dr Hilary, that everything was very much focused on the lungs, and then people were understanding there is fatigue, which is actually a neurological problem anyway, and now more and more we are realising the wider impact."
Kate documented Derek's health battle in the award-winning programme Finding Derek
Kate's husband Derek, 54, was first admitted to hospital in March 2020 after he contracted coronavirus. He stayed in intensive care for months before being discharged one year later and now requires round-the-clock care at home.
The couple share children Darcey, 15, and Billy, 12, and chronicled much of Derek's battle with the virus in the award-winning documentary, Finding Derek, which aired in March last year.
Kate Garraway: Caring For Derek airs on ITV and ITV Hub on Tuesday, February 22 at 9pm.
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