Employees are worrying about the cost impact of changes that employers have been making to insurance coverage in employee benefit plans, Colonial Life & Accident Insurance Company reports

Among full-time employees, 86% are at least somewhat concerned about unexpected medical expenses, says Colonial Life, Columbia, S.C., citing from an April 2009 survey it has just released.

In addition, 83% are concerned about increased premiums and expenses no longer covered by their plan; 81% about the addition of or increase in deductible amount; and 79% about the addition of or increase in their copay.

Conducted by Harris Interactive, the survey sampled more than 1,000 U.S. adults age 18 and over who were enrolled in an insurance program that has changed in the last year. The insurance plans were provided by employers or by spouses’ coverage.

Nearly half report seeing changes in their coverage since 2008, Colonial says. Of these, 65% report increased premiums; 56%, the addition of/increase in co-pay amounts; and 48%, the addition of or increases in deductibles.

However, only 13% say that one or more types of coverage (life, health, disability) have been eliminated.

Another worry for employees is whether their current coverage is adequate, Colonial says.

For instance, 35% thought their plans may not adequately cover their ability to earn an income for an extended time due to illness or injury, the company says.

Employees also are concerned about adequacy of coverage for serious illness (28%), unexpected emergency room visit (19%); death of a primary wage earner (19%); and basic medical care including preventive care (13%).

As for solutions, the survey found that over three-fourths (78%) of surveyed employees are at least somewhat interested in purchasing supplemental coverage or voluntary benefits to help pay for some of the expenses not currently covered by their insurance plans.