(Image credit: Getty Images) When planning for retirement, most people focus on the risks they can measure: Market volatility, inflation, withdrawal rates and how long their savings need to last. Healthcare is usually handled differently. It's often treated as a number to estimate, not something to actively manage, which can fall short of how these costs actually develop. Many of the largest healthcare costs in retirement don't come from a single emergency. They develop over time, especially when chronic conditions aren't addressed early or managed in a way patients can realistically follow. From just $107.88 $24.99 for Kiplinger Personal Finance Become a smarter, better informed investor. Subscribe from just $107.88 $24.99, plus get up to 4 Special Issues CLICK FOR FREE ISSUE Sign up for Kiplinger’s Free Newsletters Profit and prosper with the best of expert advice on investing, taxes, retirement, personal finance and more - straight to your e-mail.…