Kalamazoo County Sheriff Richard Fuller said Wednesday the cause of death will only be determined when toxicology tests are complete. But he said there were no signs of foul play and Patrick, 30, appeared to have drowned.
Patrick was fully dressed with her car keys, a pager and $100 in her pockets, Fuller said at a news conference.
Lake Charles, 15 miles east of Gary, had been searched several times since Patrick's car was found nearby on Interstate 94. The lake was covered with ice for weeks, and search teams attempted to break the ice and used sonar in an effort to find the body.
A fisherman reported the body Sunday, only a few days after the last search.
Patrick was a first-year resident in psychiatry at Western Michigan University in Kalamazoo. Fuller said she had a history that suggested emotional problems.
In September 2013, gospel singer Marvin Sapp filed court documents seeking an order of protection and accusing Patrick of stalking him. He said she moved to Michigan to be close to him, joined his church and sent him "400 pages of correspondence" that he did not answer.
[Detroit Free Press]
Notable deaths of 2014 [PHOTOS]