This study will explore the effects of cognitive behavioral therapy for insomnia (CBTI) compare to health educations in patients with type 2 diabetes (T2DM) with insomnia symptoms.

This study will recruit participants with T2DM with insomnia symptoms and randomize them to weekly CBTI or health education for 8 weeks. Outcomes will be measured at baseline and 8 week, and 16 weeks (8 weeks post intervention).

Primary outcome will be subjective sleep quality as assessed by Pittsburgh Sleep Quality Index Secondary outcomes will be fasting glucose, hemoglobin A1C, insulin levels, high sensitivity c-reactive protein, objective sleep parameters from accelerometer, depressive symptoms, daytime sleepiness, quality of life, anxiety symptoms and stress symptoms.

Inclusion Criteria:

• Type 2 diabetes mellitus age 30 to 65 years old
• Hemoglobin A1C ≥ 6.5 but ≤ 10 %
• Have poor sleep quality as assessed by Insomnia Severity Index ≥ 15
• Receive the same hypoglycemic treatments 3 months before the intervention
• If using sleep aid, the dose needs to be stable for 3 months prior to the enrollment
• Ability to use the electronic devices (computer, tablet) and assess the internet
• Willing to attend all of the 8 sessions activities

Exclusion Criteria:

• Type 1 diabetes mellitus
• Night shift work
• Insulin therapy
• Severe hypoglycemia who required hospitalization or emergency department visit in the past 6 months
• History of diabetic ketoacidosis in the past 6 months
• Medically unstable conditions eg. renal replacement therapy, liver failure, heart failure, active cancer, epilepsy, unstable cerebrovascular disease
• Psychosis, uncontrolled depression
• Untreated obstructive sleep apnea or STOP-BANG ≥ 5
• Language/communication/hearing/sight disability
• Pregnancy or lactation
• Care giver of infant
• Harmful alcohol/smoking (≥15 standard-drink in men and ≥8 standard-drink in women)