They may be among the affluent, but preretirees—those aged 50and up—cite health care costs in retirement as atop fear.

According to an annual survey from the Nationwide Retirement Institute, 69 percent ofaffluent preretirees—those with an annual household income of$150,000 or more—are afraid that their health care costs willescalate beyond their control.

Despite that, it’s not a fear they’re talking about: 52 percentsay they haven’t addressed the subject with anyone—not spouse, notchildren, and not their financial advisor.

While 63 percent of those affluent preretirees said they’re“terrified” of what health care costs will do to theirretirement plans, they’re keepingtheir mouths shut about it.

More than half of older adults who have a significant other (53percent) aren’t discussing the matter with their spouse, notwanting them to worry.

Twenty percent regard it as a personal issue, so they’re keepingmum; slightly less than that—19 percent—say they don’t know enoughabout health care costs in retirement. And in true ostrich style,10 percent say they just don’t want to think about it—as if itmight go away if ignored long enough.

Two out of three older Americans—66 percent—said they’d ratherdie than have to live in a nursing home, while 59 percent areworried that they’ll become a burden to their families.

Overall, 37 percent of adults age 50 or older and currently notretired who took part in the survey expect to never retire, and thefear isn’t limited to those with limited means. Nearly one in four(23 percent) older adults with a household income of $150,000 orhigher said the same.

Among respondents who aren’t retired, 74 percent said they’reworried about having enough money to last through theirretirement.

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The same percentage was concerned about not receiving enoughthrough government benefits, such as Social Security and/orMedicare. Others in that group said they won’t retire becausethey’re worried about having enough money to cover unplannedmedical expenses (72 percent) or health care costs eating up whatthey planned to leave for their children (55 percent).

Some are so worried about not being able to leave the kids thegoods—45 percent—that they’re actually relying on so-called“Medicaid planning”: giving all their money to their kids so thatMedicaid will pick up the tab for long-term care.