[Summary: Travel insurance ensures financial coverage against emergencies that may arise during travel. Most policies exclude certain situations which you can have covered for an additional premium. You need to know what is covered under your policy.]
Travel insurance is very important as it insures you against unforeseen circumstances you may encounter when you are on a trip. A travel insurance policy may or may not include pre-existing medical conditions and every policy will vary according to the travel insurance company and the insured person. You may have difficulty obtaining travel insurance if you have a high-risk, pre-existing condition such as heart disease, or have been diagnosed with contributing factors towards disease. If asked, you may be required to disclose information about major, existing conditions in your medical history to your insurer, even if you are not seeking coverage for pre-existing conditions.
Some travel insurance policies may cover you generally, but with pre-existing conditions excluded. This is obviously undesirable if your existing condition causes you significant problems or leaves you at risk. Some travel insurance policies will cover pre-existing conditions if you buy coverage within a short time after booking your travel. It's worth some research to find such policies. Failing that, if even possible to have your pre-existing condition covered, you may need to undergo a medical assessment and pay an extra premium for medical travel insurance or an extra-cost option in the travel policy.
Some pre-existing conditions will cause travel insurance companies to completely refuse all medical coverage, even for seemingly unrelated events. This will vary by insurer, but include conditions like terminal illness, being an organ donation recipient, having AIDS, and similar systemic risky conditions. Such people may not be able to travel secure of receiving affordable medical treatment for any condition at all. When medical cover is refused, typically the other provisions of the travel insurance policy still apply.
Travel insurance becomes increasingly difficult to get after age 55, with your age alone being considered something of a pre-existing condition. The precise cutoff for receiving travel insurance without an addition premium and/or medical examinations varies from 55 to over 70 for some insurers. As you age, you will face increasingly higher premiums and perhaps excess charges or deductibles on claims, and your existing medical conditions may be partly or totally excluded.
A medical evacuation is often a chartered trip for a patient who is not well enough to return home by other means to better facilities or to their home country. Though the need is rare, its costs can be devastating to most peoples' savings. On-balance, the cost of coverage for it is not terribly great. It typically involves traveling with medical personnel looking after you throughout return home, along with any needed equipment, medications, etc. Although some people have worldwide medical travel insurance coverage as part of their everyday health insurance, it almost never comes with international medical evacuation. Even if you are willing to forgo all other types of international travel insurance, no one should ignore medical evacuation coverage.