OBJECTIVE: The role of social support in bipolar disorder is poorly understood. It is known that young and middle-aged patients with impaired social support are more likely to be treatment resistant and have increased hospitalization. However, the role of social support in elderly patients with bipolar disorder has not been studied. Our purpose was to evaluate social support in older adults with bipolar disorder compared with peer controls and younger bipolar patients. In addition, we looked at the role of social support in the age of illness onset. METHODS: We evaluated social support of 29 older subjects with bipolar disorder (age 50 or older) and 56 younger subjects with bipolar disorder using the Duke Social Support Index, comparing them to non-psychiatric, peer controls. Using logistic regression we then examined the relationship of demographic, social support factors, and age of onset. RESULTS: Both older and younger bipolar subjects perceived their social support as inadequate (OR = 14.98; OR = 9.05) compared with similar aged controls. Younger bipolar subjects also had less social interactions than younger controls (OR = 4.63). These findings remained significant when controlled for gender, marital status, race, and education. No significant differences were noted between early-onset and late-onset bipolar subjects. CONCLUSIONS: Older and younger bipolar patients have decreased perceptions of social support than older controls. No effect was found based on the age of illness onset. In addition, younger subjects had less social interactions than peer controls.