Here’s something that has gotten lost in the drive to institute universal health insurance: Health insurance doesn’t automatically lead to health care. And with more and more doctors dropping out of one insurance plan or another, especially government plans, there is no guarantee that you will be able to see a physician no matter what coverage you have.

Consider that the Medicare Payment Advisory Commission reported in 2008 that 28% of Medicare beneficiaries looking for a primary care physician had trouble finding one, up from 24% the year before. The reasons are clear: A 2008 survey by the Texas Medical Association, for example, found that only 38% of primary-care doctors in Texas took new Medicare patients. The statistics are similar in New York state, where I practice medicine.

More and more of my fellow doctors are turning away Medicare patients because of the diminished reimbursements and the growing delay in payments. I’ve had several new Medicare patients come to my office in the last few months with multiple diseases and long lists of medications simply because their longtime provider — who they liked — abruptly stopped taking Medicare. One of the top mammographers in New York City works in my office building, but she no longer accepts Medicare and charges patients more than $300 cash for each procedure. I continue to send my elderly women patients downstairs for the test because she is so good, but no one is happy about paying.

The problem is even worse with Medicaid. A 2005 Community Tracking Physician survey showed that only 50% of physicians accept this insurance. I am now one of the ones who doesn’t take it. I realized a few years ago that it wasn’t worth the money to file the paperwork for the $25 or less that I received for an office visit. HMOs are problematic as well. Recent surveys from New York show a 10% yearly dropout rate from the state’s largest HMO, the Health Insurance Plan of New York (HIP), and a 14% drop-out rate from Health Net of New York, another big HMO.

The dropout rate is less at major medical centers such as New York University’s Langone Medical Center where I work, or Mount Sinai Medical Center, because larger physician networks have more leverage when choosing health plans. Still, I am frequently hamstrung as I try to find a good surgeon or specialist to refer one of my patients to.

Overall, 11% of the doctors at NYU Langone don’t participate in at least two insurance plans — Aetna or Blue Cross, for instance — so I end up not being able to refer my patients to some of our top specialists. This problem, in addition to the mass of paperwork and diminishing reimbursements, is enough of a reason for me to consider dropping out as well.

Bottom line: None of the current plans, government or private, provide my patients with the care they need. And the care that is provided is increasingly expensive and requires a big battle for approvals. Of course, we’re promised by the Obama administration that universal health insurance will avoid all these problems. But how is that possible when you consider that the medical turnstiles will be the same as they are now, only they will be clogged with more and more patients? The doctors that remain in this expanded system will be even more overwhelmed than we are now.

I wouldn’t want to be a patient when that happens.

Dr. Siegel, an internist and associate professor of medicine at the NYU Langone Medical Center, is a Fox News medical contributor.