So perhaps PH doesn´t and will not suffer physically from dementia, "only" memory/intellectual wise. And THAT I believe is something we see with his constant "I want to be king." The court can´t control him/his disease anymore. It´s been in the pipeline with the flu at QMII´s birthday as the drop that maked the glass run over.
Perhaps a better phrase is: Senile dementia
But dementia is a physical condition. It is a progressive deterioration of the brain and it affects memory, thinking, language, understanding, and judgment. Eventually it affects movement and the ability to speak and swallow. If the person lives long enough, the deterioration in brain function will eventually cause their body to stop working completely. But it can take over ten years to reach that stage.
And it can take a long time to diagnose because in the early stages the afflicted person's behaviour can change very slowly, and the symptoms can be consistent with a number of things. In the early to moderate stages the person can live a relatively normal life as long as they have people around to watch them constantly, and indeed they can take great pleasure in life. It's only when they are left on their own that they get into trouble because, for example, they have forgotten how to make a cup of tea. Apparently that simple task actually involves several brain processes, and if the brain isn't working they way it should, those processes are interrupted and the afflicted individual will stand in the kitchen staring at the cupboards having no idea what to do next. And they might call their house a boat. But they are friendly and happy and can hold a conversation and enjoy their meals someone else cooks for them. And, of course, there is the safety issue of hotplates and gas being left on, etc.
People with moderate stage dementia can even function in an ostensibly normal manner even though they have forgotten precisely who you are. Not what your name is, just who you are in relation to them. You can, for example, take them out to an agricultural show and be sitting with them watching the woodchopping and having an ostensibly normal conversation with them and then they suddenly drop a clanger like, "That old woman I'm living with, that I call Mum, why does she have our mother's dressing table?" And they are deadly serious, and you are left feeling very unsettled for a few days, until they say or do something that unsettles you even more. Which they will, you can bet on that.
So I have no trouble believing that Henrik could - I stress "could", since we don't know - have early stage dementia and still be able to enjoy travel very much, as long as he has people with him who are familiar to him and who can keep an eye on him and make sure he has what he needs, when he needs it.
And if he does indeed have this condition, it was best that he retire now. For everyone's sake. If. There are a lot of ifs.