Most people grow out of teenage acne (however if you acne is severe it may persist into adult life). Adult acne is more persistent, and can have a significant hormonal component to it. Factors such as stress play an important role in adult acne.
Adult acne can be defined as acne over the age of 25, and often presents as painful deep cysts along the chin and jawline areas. Some people pick at these lesions as they are blind ending. It is important treat adult acne as this type of acne tends to cause scarring.
Anti hormone treatments or a low dose of isotretinoin can be extremely effective in treating this form of acne.
More on hormone treatments for acne