Bloomberg

Shares of both American Airlines (AAL) and Delta Airlines (DAL - Get Report)  were lower on Thursday after Deutsche Bank analyst Michael Linenberg issued a downgrade on both airlines, and also lowered his price targets.

In a research note to clients, Linenberg downgraded both American and Delta to hold from buy and lowered his price targets on both companies' shares - to $40 from $47 for American and to $55 from $66 for Delta - mainly due to both airlines' exposure to what he sees as a potentially slowing global economy.

As of mid-afternoon, both American and Delta were down by a little more than 2% each, along with other airlines' shares.

"The stream of global macro data points have been less encouraging of late, suggesting to us that the industry risks are now more biased to the downside. That said, we are finding it more difficult to advocate 'new money' positions in names with the most exposure to global markets."

However, Linenberg also noted that American and Delta will "respond quickly to address any possible fall-off in demand," and also pointed to more domestic-focused names including Alaska Air (ALK - Get Report) , Southwest Airlines (LUV - Get Report)   and Spirit Airlines (SAVE - Get Report) as being "supported by a U.S. economy that continues to perform relatively well."

Linenberg also adjusted his price targets on several other airlines, including Alaska, which he cut to $73 from $75; JetBlue (JBLU - Get Report) , lowered to $20 from $22; SkyWest (SKYW - Get Report)  , cut to $68 from $75; Spirit, down to $75 from $79; and United Continental (UAL - Get Report) , which he reduced to $105 from $109.