This depends heavily on the specific policy and insurer, so there's no single universal answer. Many UAE health insurance plans apply a waiting period or specific exclusions for pre-existing conditions, particularly for chronic or serious conditions disclosed at application, while some policies, especially certain employer-provided group plans, may offer more inclusive coverage from day one. Reading the policy's specific pre-existing condition clause, rather than assuming coverage either way, is the only reliable way to know what applies to you.
Check your own exact figures with the Insurance Comparison Tool - free, in under a minute, no sign-up required.