Health insurer Humana Inc. said on Wednesday that its second-quarter profit rose 18 percent, helped by growth in both its direct-to-customer division and the unit that markets plans to employers.

The company, which specializes in private Medicare plans for the elderly, reported net income of $420 million, or $2.63 per share, up from $356 million, or $2.16 per share, a year earlier.

Revenue rose to $9.7 billion from $9.2 billion, below analysts' expectations of $10.3 billion, according to Thomson Reuters I/B/E/S.

The company raised its full-year earnings forecast to a range of $8.65 to $8.75 per share to reflect the second-quarter results. Analysts were expecting $8.68 per share.

Humana said it had spent 83.4 percent of premiums it took in on medical benefits, down from 83.5 percent a year earlier. It had 12.37 million medical members at the end of the quarter, and another 8.27 million people were in dental, vision and other supplemental benefit plans.