UPDATE 1-ResMed quarterly profit rises 32 percent

* Net income $0.51/share vs $0.48/share estimate

* Revenue rises 8 pct to $227.9 million

LOS ANGELES, May 7 (Reuters) - U.S. respiratory equipment maker ResMed Inc (RMD.N) reported a 32 percent rise in quarterly profit on Thursday, citing higher sales of its devices to assist sleep-related breathing disorders, as well as lower costs.

The company posted a net profit of $39.2 million, or 51 cents per share, for its fiscal third quarter ending in March, compared with $29.7 million, or 38 cents per share, a year earlier.

Analysts had expected a profit of 48 cents a share, according to Reuters Estimates.

Revenue jumped 8 percent to $227.9 million for the quarter, just short of the $228.6 million forecast on average by analysts.

ResMed and bigger rival Respironics Inc control about 80 percent of the $2 billion U.S. market for sleep breathing devices, a rapidly growing market as people become more aware of the links between sleep disorders and heart disease and diabetes.

Shares of ResMed, which rose 2 percent to close at $38.99 on the New York Stock Exchange, were unchanged after hours. (Reporting by Deena Beasley; Editing by Richard Chang)