While no significant associations between cytokines and ASD without ID or ADHD were observed, elevated levels of the pro-inflammatory cytokines IL-1β and MCP-1, the hematopoetic growth factor IL-7, the inhibitory IL-10, and the Th2-cytokine IL-13, were associated with ASD with co-occurring ID. Here, IL13 is linked to attention deficit-hyperactivity disorder.