NEW YORK, April 7 (Reuters) - The National Transportation Safety Board is expected to reveal this week that the driver of the train that derailed in December in New York City, killing four passengers, had an undiagnosed sleep disorder, the New York Times reported on Monday.
William Rockefeller, the engineer at the controls of the Metro-North commuter train that derailed in the Bronx on Dec. 1, suffered from sleep apnea, which can cause drowsiness, the paper said, citing an unnamed person with knowledge of the impending announcement.
The disorder, characterized by shallow or interrupted breathing during sleep, often goes undiagnosed, according to the National Institutes of Health.
Rockefeller's condition appeared to have been aggravated by his switching to an early-morning shift about two weeks before the crash, the Times reported.
A spokesman for the safety board declined to address the report, but said "factual information" regarding the accident may be released later on Monday.
Investigators said the seven-car train was traveling nearly three times faster than the speed limit as it approached a curve in the track just outside the Spuyten Duyvil station in the Bronx. Besides the four deaths, more than 70 people were injured.
A lawyer representing Rockefeller did not immediately respond to a request for comment. The engineer's representatives had earlier said that Rockefeller appeared to have dozed off before the derailment. (Reporting by Jonathan Allen; Editing by Scott Malone and Bernadette Baum)