Studies by health insurance trade group America's Health Insurance Plans (AHIP) and Information Strategies, Inc.(ISI) in the first part of this year reveal interesting trends in Health Savings Accounts (HSAs) participants.

While Health Savings Accounts have grown to more than 12 million covered lives, some, interesting trends are surfacing refuting critics claims they are discriminatory as to age and income

According to AHIP, the age group 0-19 had the highest percentage of insured covered by HSAs, at 26%. Most were enrollees covered under family plans. The second-highest percentage was those ages 50-59, at 21%. The lowest percentage was those 60 and older, 9%. Those ages 20-29 and 30-39 each was at 13%, and those 40-49 were at 19%.

This statistic alone bears evidence of the wide-spread acceptance and usage of HSAs particularly amongst younger individuals.  The data tracks with ISI’s research findings that individuals with families are most likely to choose an HSA. This trend is particularly strong if they have children. Employer-sponsored plans also reflect this trend with families more often opting for HSAs if multiple-options are available.

However, experts are concerned that enrollees don't understand the limitations of their coverage.

For instance, recent research has shown that enrollees in high-deductible plans tend to use less preventive care and that some people don't understand their coverage.

A RAND Corp. study released in March found that people with high-deductible plans saved money during the first year they were enrolled, but mostly because they received less preventive care. This was puzzling to researchers, because many high-deductible plans cover at least one annual preventive visit with no out-of-pocket cost.

Experts say employers and health plans need to make sure they do a good job explaining coverage to their employees and members.

AHIP, meanwhile, called on the government to protect high-deductible plans and HSAs on the grounds that so many people have chosen them. The group is worried that the Patient Protection and Affordable Care Act will threaten the business because health plans will face medical spending minimums.

Other statistics from AHIP's report:

• Minnesota, at 14.9%, had the highest percentage of enrollment in high-deductible plans paired with an HSA of any state. The percentage covers those younger than 65 who have private insurance. Following Minnesota were Vermont, 11.4%; Colorado, 11.3%; Montana, 10.8%; and Ohio and Indiana, each at 10.6%.
• Hawaii had the lowest percentage of enrollment in HSAs paired with a high-deductible plan -- 0.2% -- among those younger than 65 with private insurance. Following Hawaii were West Virginia, 2.1%; Mississippi, 2.4%; New Mexico, 2.6%; and Massachusetts, 2.7%.
• California had the greatest number of enrollees of any state, with 1,073,319. It was followed by Texas, 844,832; Ohio, 728,868; Illinois, 690,509; and Florida, 656,243.

Preferred provider organizations, at 92%, were by far the most popular health plan type to be paired with an HSA.