S&P Global Ratings lowered the rating to "AA-" from "AA" on Toledo, Ohio-based ProMedica Healthcare Obligated Group's series 2015A, 2015B, 2011A, 2011D, 2008D, 2011B and 2011E bonds.
"The rating action reflects our view of ProMedica's expected weaker operating performance over the next couple of years and an expectation of potentially lighter-than-historical margins over the medium term," said S&P analyst Suzie Desai.
The outlook is stable, reflecting S&P's view of ProMedica's leading business position and ongoing strategic investments.