New approach for analyzing self-reporting of insomnia symptoms reveals a high rate of comorbid insomnia across a wide spectrum of chronic diseases.

•Seventy-eight percent of US-based PatientsLikeMe respondents were at risk for National Sleep Foundation (NSF)-defined insomnia.•Trouble falling asleep was the sleep symptom most likely to result in self-reporting insomnia.•Forty-four percent awaken during the night and 42% awake unrefreshed, but these symptoms receive less attention.•Insomnia was worse in fibromyalgia (92%), Crohn's disease (88%), depression (85%), and rheumatoid arthritis (RA) (85%).•Only 34% of patients reporting severe insomnia had ever received an insomnia diagnosis.