Arthritis is commonly first diagnosed in older cats during the winter months. This is due to the lower temperatures in winter can seize up the limbs and make symptoms of Arthritis and stiffness more painful. There are various things that you can do to make their lives more comfortable. When you first notice it they will have pain so anti-inflammatory and medications will help with immediate relief. Long term you will need to research for joint supplements which can be purchased on line as well as from your vet. Glucosamine can be purchased from Holland and Barrett or from the internet which can be of great help to your cat once it gets into their system which can take up to several weeks to show a difference. This is a long term treatment and tablets can be crushed and simply sprinkled onto their food. Soft beds /blankets, pet friendly hot water bottles or heaters, or simply being able to curl up next to a radiator will make them more comfortable.