Sanitoa was 21. No cause of death was released.
University spokesman Derek Inouchi said the death did not happen on campus and that Sanitoa was not involved in any athletic department activities at the time of his death.
According to Matlin, the football team met Friday to discuss Sanitoa's death. Campus counselors were present at the meeting and will continue to be available to the team, Matlin said.
"Scheyenne was a tremendous young man, and we are devastated by this news," Matlin said in the statement released Friday. "It's always heartbreaking to lose a member of our UH ohana, particularly when it's one of our young student-athletes. Our deepest thoughts and prayers are with his family, his friends, his teammates and to all those who knew and loved him."
A redshirt junior from Fagatogo, American Samoa, Sanitoa appeared in 12 games last season, including two starts, and finished with 30 tackles.
The Associated Press contributed to this report.