DiSesa headed up the agency's flagship New York creative department until 2004 when she left to write a book about her experiences in the ad business.
Joyce King-Thomas, executive vice-president and chief creative officer, took over the chief creative role when DiSesa left.
DiSesa said: "Although I like the chairman job and being an author has its moments, my heart is with the creative department. When Joyce asked me to think about taking on this responsibility, the opportunity to partner with her on J&J was too wonderful to resist."
King-Thomas said: "For both Nina and McCann, the timing of this responsibility is perfect. Nina's book has been turned in to Random House, allowing her to devote her considerable energies to J&J, and we get to deploy one of the best creative talents in the business against this important client's expanding business."
Irwin Warren has recently retired from heading the Johnson & Johnson account but will remain a consultant to McCann Erickson. The agency handles $200m (£100m) in worldwide advertising revenue for the brand, which includes the Acuvue and Band-Aid brands.
Before joining McCann Erickson in 1994, DiSesa worked as executive creative director at JWT in Chicago.