They may not be confident their plan can handle their changing needs. At the same time, they have a number of different reasons as to why they're reluctant to make a change. For example, many people find the process of comparing Medicare plans too confusing and difficult, especially since there could be dozens available."

Other barriers to change:

• Too confusing given the many different Medicare options.
• Too hard to find information or to compare different plans.
• Concerns about keeping doctors and securing treatment.
• Concerned a pre-existing condition would not be covered under a new plan.
• Concerned the health provider they wanted to use would not be a part of the new plan.
• Have traditional Medicare with a group health plan through a former employer.
• Are unaware they could switch plans.
• Believe they were unable to afford other options.

"It can appear safer to stick with your existing Medicare plan because of some of these unknown factors," Gada said. "But there is a greater risk that–as your health changes and healthcare costs continue to rise–your current plan won't provide what you need. You may miss out on valuable benefits from re-evaluating your Medicare options during annual enrollment season."

Reasons to Switch

Although only 5 percent of seniors surveyed have switched plans, the most common reasons for switching were to save money and receive better service. Specifically, reasons for switching included the new plan:

• Costs less (4 of 10 respondents);
• Offered better service and customer support (3 of 10);
• Offered better prescription drug coverage (1 of 10); and
• Offered coverage for healthcare/procedures not covered under the old plan (1 of 10).

The Allsup survey also found that 25 percent of seniors report their health had declined since enrolling in Medicare.

"During annual enrollment, you have a very important window to evaluate and make changes to your Medicare coverage," Gada said. "It's particularly important to do so when your health condition changes to make sure you have the best plan to support your new needs."

Limited Support

Most seniors have limited support in choosing Medicare coverage or enrolling in a Medicare plan, according to the survey:

• Two-thirds of respondents (67 percent) reported they select their Medicare plan with no help.
• Twenty-five percent say they look for support from a spouse, adult child or other family member.
• Eight percent from others, including their doctor, a Medicare office, friends or a financial advisor.
• More than three in four seniors (76 percent) receive no support when it came to enrolling in Medicare
• Thirteen percent receive support from a family member and 11 percent from others, including social services and financial advisors.

"Before retiring, most seniors looked to their employers' benefits administrators for help in selecting healthcare coverage. Now, their health may be changing and good healthcare coverage is even more critical," said Gada. "However, they no longer have the support of their employer. Too many rely on their own limited knowledge, rather than seeking experienced, objective support to make sure they receive the quality of coverage they need."