SECRET BEHIND LINDA RONSTADT’S VEGAS MELTDOWN

Linda Ronstadt suffers from a chronic, debilitating disease — and friends believe it triggered her bizarre headline-making meltdown in Las Vegas.

Irate fans stormed out of her July 17 performance at the Aladdin hotel when she lashed out at President Bush during her concert — but they didn’t know she suffers from Hashimoto’s disease, which medical experts say can lead to extreme behavior.

The singer — whose hits include “You’re No Good,” “Blue Bayou” and “It’s So Easy” — was diagnosed with the chronic thyroid disorder in 1997.

SYMPTOMS

Symptoms can range from mild to severe — from chronic fatigue and lack of concentration to clinical depression, confusion, hallucinations and even psychotic episodes.

What’s more, patients treated with thyroid hormone must get precise dosages and be carefully monitored or they can suffer bouts of fear, hostility and agitation.

Some of Ronstadt’s friends are worried her condition has gotten so severe she may have become unstable.

And it’s not just because the entertainer holds strong political views, but because she goes to extremes, expressing them at the wrong time and going so far as to compare the President to Adolf Hitler.

“Linda’s battled this glandular disease for a while now and it had really taken a toll on her,” Mark Bego — author of the Ronstadt biography “It’s So Easy” — told The ENQUIRER.

“She was very debilitated and had gained a lot of weight, but the irony is she’d recently gotten it under control. When I saw her in concert in June in New York City, she looked a lot better than she had in a while. She had lost some weight and was in good spirits.

“I understand that when she was in Las Vegas, though, she’d been suffering from a severe sinus infection and her ears were completely clogged up.

“Linda clearly wasn’t feeling well and it caused her to blow up onstage.”

STAGE FRIGHT

The 58-year-old singer admits to a long-running battle with stage fright and she’s been loud and clear about hating Las Vegas. Add to that volatile mix her illness, and it all combined to push her over the top — she gave a performance that got her banned from the Aladdin.

Astonishingly, in an interview she gave to the Las Vegas Review-Journal before the show, the star said with a laugh:

“I keep hoping that if I’m annoying enough to them, they won’t hire me back.”

An old friend told The ENQUIRER: “Linda has become unhinged . . . and it’s got to have something to do with her longtime sickness.”

The singer has always been outspoken politically but now “she’s gone over the edge,” said another source, who believes that “her thyroid disease contributed to these outbursts.”

Some 4,500 people had been enjoying Ronstadt’s performance at the Aladdin and she planned to perform “Desperado” as an encore. She dedicated the song to a “great American patriot” — filmmaker Michael Moore.

ANTI-BUSH

Then she urged the audience to see his controversial anti-Bush movie “Fahrenheit 9/11.” Some audience members got so upset they flung their drinks into the air and walked out amidst loud boos.

“It was a very ugly scene,” said Aladdin president Bill Timmins. “She praised him (Moore) and all of a sudden all bedlam broke loose.”

The furious executive did not allow the singer back into her suite and she was escorted off the property.

Friends say Linda feels she’s been targeted by the right wing for her political views.

But hotel spokeswoman Tyri Squyres said it wasn’t the singer’s message per se that infuriated the management.

“She wanted to incite the audience, and she incited them to the point where they were very upset . . . She was hired to entertain — not to preach.” — MICHAEL GLYNN