As a person of somewhat advanced years, I'm wondering why there is no fiction category for older adults. There are any number of categories for children's books (middle-grade, picture books, early readers, YA), but then there is just this great expanse of fiction called 'adult'. Why isn't there a category for us older adults?
Dear Aged Reader,
You're right. There are a lot of different categories that sit under the banner of children's books and none once you hit the adult market. That's because children are learning to read, and these categories are helpful in identifying both the reading level of the book, and the content. Someone who is reading early readers is likely around six to eight years old and not totally confident with reading yet. Therefore both the language used in the book, and the subject matter, will be targeted toward people of this age group.
Adult books are targeted toward people who can read and rather than being categorized by age group, are cateogrized by genre (mystery, sci-fi, historical fiction, romance etc). There are certainly books within any one of these genres that feature older characters and their struggles and concerns, but these books are not specifically targeted only at readers of more advance years. Just as books about characters in their thirties aren't targeted only at readers in this age group. It is expected that adults will have developed their tastes and have preferences already for the kind of books they read.
That said, the population in the western world is aging, and the number of older readers is growing. Publishers are taking note of this, and romance readers especially will find there is an increase in the number of 'second-chance' romance novels featuring characters of more advanced years available. A number of books featuring older protagonists have featured on bestseller lists in recent years too (A Man Called Ove, The One Hundred Year Old Man Who Climbed Out the Window and Disappeared to name a couple). A quick look at Goodreads shows there are a number of lists featuring books with more mature protagonists.
So to answer your question more succinctly, no, there is no category for older readers, but there are certainly books out there that feature older characters and storylines that will resonate with an older audience. It just might take a bit of searching within your preferred genre to find them.