It depends on the type of policy you have. If you have a non-cancelable policy, the insurance company can't increase the premium or cancel your policy.We advise younger purchasers of disability to get a non-cancelable policy to "lock in" their rate.
If you don't have a non-cancelable policy, as you get olderyour premiums can increase. This is because risk of a disability increases with age and thus the cost to insure you increases. Also,insurance companies in some instances may increase the premiums for all their members. This is due to the change in the underlying risk of the insured group, which has resulted in higher payouts than premiums they are taking in. But raising rates requires regulatory approval (meaning the insurer can't do this arbitrarily or on a specific person). Again, a non-cancelable policy will enable you to avoid these premium hike situations.