This is my first ever Ask Historians answer, and I'm not really a historian so if this isn't up to snuff I apologize. I'm also a terrible writer.

King Alfred the Great (849-899), famous for driving the danelaw Vikings out of Wessex and becoming king of much of England by the end of his life, was also rather famously known to have had a major indigestion disease of some sort, thought now to most likely be Crohn's Disease.

Our source on his disease comes mostly from Asser, a Welsh monk who knew him and began to write a (probably) uncomplete biography of him during his life time called "Life of King Alfred". Because Asser was a monk and knew him personally, "Life" can begin to border on Hagiography at times but is the best source we have for many of the smaller details of Alfred's life, including his disease, known variously as "ficus" or "piles" within text.

Asser tells us that Alfred had this disease because he was prone to temptation to "carnal desires" and prayed to God to give him some sort of minor disease that would strengthen his resolve and holiness. He does specify minor, because he doesn't want to be viewed as useless and infirm by others:

Almighty God would exchange the torments of the malady which then afflicted him for some other lighter disease, provided that such disease should not show itself outwardly in his body, lest he should be useless and despised — for he had great dread of leprosy or blindness, or any such complaint as instantly makes men useless and despised at its coming.

Asser goes on to tell us how much torment Alfred was in nearly constantly, and although he doesn't say what other people's opinion of him was, we do get this small fragment that may answer your question (emphasis mine):

a worse one seized him, as I have said, at his marriage, and this incessantly tormented him, night and day, from the twentieth to the forty -fifth year of his life. But if ever, by God's mercy, he was relieved from this infirmity for a single day or night, or even for the space of one hour, yet the fear and dread of that terrible malady never left him, but rendered him almost useless, as he thought, in every affair, whether human or divine.

So we know at least that Alfred himself worried what others would think of him because of his disease.

Overall the disease didn't seem to be much of a problem for him as he feared, he's still one of the most famous Kings in English history and participated in a few decisive battles, and Asser mentions elsewhere that he was still able to hunt, govern, and perform his other duties pretty much unabated, which he attributes to his holiness and strong resolve/character.

Sources: Assers "Life of King Alfred", section 74, pages 36 & 37.

"Alfred the Great: A Diagnosis" Journal of the Royal Society of Medicine

EDIT: Formatting fixes

EDIT 2: Corrected citation to reflect PDF version of the book rather than the jumbled plaintext version.

EDIT 3: Grammer