DETROIT — A former patient has told a Detroit newspaper that a late University of Michigan doctor accused of sexual abuse wrote letters certifying students were gay so they could avoid military service during the Vietnam War in exchange for sexual contact. The Detroit Free Press reports that Ed Glazier said he saw Dr. Robert E. Anderson in 1969. Glazier, who is gay, said friends had told him that Anderson was willing to write letters certifying students as gay in exchange for “personal contact.” The university's president apologized last week to anyone hurt by Anderson. The school announced it was investigating complaints of abuse from five former patients.