Health insurer Aetna ( AET) Thursday reported a higher first-quarter profit and reaffirmed 2004 guidance, as it managed to boost membership in its plans by 2.6% during the period. The Hartford, Conn.-based company said net income rose 11% to $365.8 million, or $2.28 a share, vs. $330 million, or $2.12 a share, in the year-ago period. Excluding items, the company earned $1.75 a share, vs. $1.34 a year ago. The consensus estimate was for $1.72 a share, according to Thomson First Call. Revenue rose to $4.82 billion from $4.66 billion a year ago. The company said medical membership rose 342,000 in the quarter to 13.3 million, compared to the end of 2003. The company reaffirmed full-year EPS of $6.60 to $6.75. The consensus estimate is for $6.81 per share. Shares closed at $87.85 Wednesday.