(REUTERS) -- Nasdaq OMX Group Inc.'s quarterly profit fell , due in part to expenses associated with debt refinancing, the impairment of an available-for-sale investment security and merger and strategic initiatives.

The Nasdaq Stock Market parent earned $82 million, or 45 cents per diluted share, in the fourth quarter, down from $137 million, or 69 cents per share, a year ago.

(Reporting By John McCrank in New York; Editing by Derek Caney)