According to a media advisory as posted on the University of Colorado Boulder News Center:
The Office of Tibet in Washington, D.C., today informed the University of Colorado Boulder that the Dalai Lama will not be able to attend any of his planned events in the United States next month for medical reasons.
The UCB News Center shared this statement from the Office of Tibet:
His Holiness arrived in the United States earlier this week for a medical evaluation. Upon completion of the evaluation, the doctors have advised that His Holiness take complete rest. As a result, His Holiness will be returning to Dharamsala, India, next week and will not be able to visit the United States next month. We deeply regret cancellation of the visit.
Read the full UCB News Center post, which includes details on refunds for ticketed events, here.
Update – September 28: Multiple news outlets have confirmed that the Dalai Lama was at the Mayo Clinic for a medical checkup on Thursday. Read more.
UMASS has released a similar statement about the cancellations; UMASS Amherst was a planned stop in the Dalai Lama’s autumn 2015 travels.
The Dalai Lama had planned a visit to Naropa University on October 21. Naropa President Charles G. Lief offered Lion’s Roar this statement:
The Naropa University community was very sorry to hear of His Holiness’ illness. We are of course disappointed that we will not be able to share time with His Holiness in Boulder but are most focused on urging him to rest and regain his strength. The world needs to hear the Dalai Lama’s message of Compassion in Action for years to come.
Naropa will do what we can to assist our friends at the Tibetan Association of Colorado in recovering the costs already incurred in planning for the visit.