However, the doctors did not report their concerns to Andreas Lubitz’s employers, because of German patient privacy laws, the Marseille prosecutor Brice Robin told reporters in Paris.
Robin could not confirm if Lubitz’s vision troubles were real or imagined.
Robin met with families of victims yesterday and updated reporters on the status of the investigation into the March 24 crash, which killed all 150 people on board.
Families are just starting to receive remains of their loved ones and will start holding burials in the coming days and weeks.
Robin said the investigation so far “has enabled us to confirm without a shadow of a doubt... Mr Andreas Lubitz deliberately destroyed the plane and deliberately killed 150 people, including himself”.
Investigators say Lubitz locked the pilot out of the cockpit and flew the plane into a French mountainside, after having researched suicide methods and cockpit door rules and practiced an unusual descent.
In a new development, Robin said information from his tablet PC showed Lubitz had also investigated vision problems, and “feared going blind” — a career-ending malady for a pilot. Lubitz had suffered depression in the past.
Lubitz had seven medical appointments within the month before the March 24 crash, including three with a psychiatrist, said Robin.
Some of the doctors felt Lubitz was psychologically unstable, and some felt that he was unfit to fly, but “unfortunately that information was not reported because of medical secrecy requirements,” said the Marseille prosecutor.
Robin said that Lubitz sent an email to one doctor just two weeks before the crash, saying he had doubled his dose of an antidepressant he was on in a failed attempt to end near-sleepless nights as a result of worries about his vision.
In Germany, doctors risk prison if they disclose information about their patients to anyone unless there is evidence they intend to commit a serious crime or harm themselves.