Pin down where and how the coat has changed
Run your hands slowly over her whole body in good light and note exactly what you find. Is the thinning even along her back and sides, or concentrated in patches — over her hips, along her spine, behind her ears, on her belly? Does the remaining fur feel dry and brittle, greasy, or fine but sparse, and is there more dandruff, matting, or loose hair on her bedding than there used to be? A coat that is dull everywhere tells a different story from one bald patch she licks constantly. Take a clear photo of the most affected areas in natural light, and another of her whole body from above, so you can repeat the same shots later and compare honestly rather than relying on memory.
Track her grooming, because senior coats often reflect effort
A glossy coat is partly manufactured by the cat herself: regular grooming spreads oils, removes loose fur, and keeps the skin stimulated. Senior cats with stiff necks, sore hips, or extra weight often cannot reach their back, sides, and hindquarters, and those are exactly the areas that turn dull, flaky, or matted first. Note which parts of herself she still washes, whether grooming sessions have shortened, and whether she has started licking one spot obsessively instead — overgrooming a sore joint or an itchy patch can thin the coat locally while the rest looks normal.
Log the whole-cat changes that travel with coat changes
Coat quality rarely changes alone. Keep a short daily or weekly note of her appetite and how much of each meal she finishes, her drinking, her litter box habits, her weight as you feel it along her ribs and spine, and her energy — whether she still seeks her usual spots and company or sleeps more and interacts less. Note any vomiting, loose stools, or increased shedding around the house. These parallel details matter because a dulling coat alongside weight loss and bigger thirst points your vet in a different direction than a dull coat in a cat who eats well, holds her weight, and simply cannot reach her back anymore. Write dates beside entries; a six-week trend is far more useful than an impression.
Note diet, home changes, and anything new on her skin
Record what she actually eats now, including any recent food change, treats, or a drop in how much of her usual food she finishes, because a coat reflects nutrition over weeks. Note new stresses at home — a move, building work, a new pet, a changed routine — since stress can show up as shedding or overgrooming. When you part the fur in the thinned areas, look at the skin itself: redness, scabs, flakes, bumps, or a musty smell are all worth describing to the vet, as is any flea dirt you find even on an indoor cat. Do not apply oils, supplements, or skin products while you wait for the check unless your vet advises them; they can blur what the coat and skin are trying to show.
Bring a timeline, not just a worry, to the appointment
At the check, lead with the sequence: when you first noticed the thinning, where it started, how it has spread, and what else changed in the same period. Show the dated photos, the grooming observations, and the appetite and weight notes, and mention any area she overgrooms or cannot reach. Ask what your vet wants you to monitor between visits and how quickly they want to hear if the thinning accelerates, her weight drops, or new skin lesions appear. If she stops eating, develops sores, or seems unwell in herself, do not wait for the routine appointment — call sooner, because in a senior cat a coat change plus feeling unwell deserves prompt attention.
Keeping those dated photos, grooming notes, and appetite records together in her KinsLe Pet Passport means the coat change arrives at the vet check as a clear history your vet can act on straight away.