Facing increasing demand for information and services, the Alzheimer’s Association, New York City Chapter, has doubled its space at 360 Lexington Ave., at 40th Street.

The nonprofit has signed a 15-year lease and expansion with Boston-based AEW Capital Management for 30,411 square feet. The organization added 15,201 square feet, the entire third floor, to its existing 15,210 square feet on the fourth floor.