Paul had the right idea with this, although if you actually had to go to court on this it wouldn't be the ideal resolution of this. Generally, tenants can get out of residential leases in New York in one of several ways. First, the landlord might be willing to simply let you out of the lease, if there's a ready market for re-letting the premises, particularly if you're willing to pay for the interregnum in the lease. So if you're willing to pay for a month or two of extra rent, you can probably terminate the lease amicably. Given your personal medical situation, I would think that most landlords would be understanding and try to work it out with you.
Second, if you want to go in the opposite direction, some tenants just give their landlord notice and leave. You'll lose your security, but it's generally easier for the landlord to simply re-let the premises, keep your security, and move on, than to try to pursue you for the lost rent. The court costs are just too high. This has some danger to it, though, because the landlord could pursue you, and at the very least you would have a little difficulty in the future if landlords want to know the circumstances of your past rentals.
I would suggest you talk to your landlord, see if there's any accommodation he or she is willing to do. If you get some difficulty, you should consult with a lawyer about your options with regard to breaking your lease based on your potential disability. Good luck.