Even low blood lead levels linked to gout risk

Yasuyoshi Chiba, AFP/Getty Images

In an interview, Sehgal said that many people with elevated lead levels are exposed to the metal at work - in industries like mining, construction and battery making.

If you've ever worked with lead, tell your doctor and ask whether a blood test is a good idea, said Sehgal, a professor of community health improvement at Case Western Reserve University in Cleveland, Ohio.

"I don't think that everyone should have their lead levels checked," Sehgal said.

Krishnan agreed. He also noted that while the average blood lead level in the U.S. is 3 mcg/dL, "that would include a large number of people with zero or near-zero levels."

But Krishnan said that if a person has gout and no known risk factors for it, like obesity, doctors could consider lead testing.

Typically, if someone's lead levels are elevated, it would be important to reduce any known exposure to it.

Besides job exposure, Krishnan said that people can inhale lead through cigarette smoke or lead-containing dust; deteriorating lead-based paint in an older home, for example, can contaminate household dust.

Lead can also be in drinking water, especially in older homes with lead-based pipes. And some people are exposed through hobbies, like working on cars, or making glazed pottery or stained glass.

When a person's lead levels are particularly high, a treatment called chelation therapy might be recommended. That involves giving certain drugs that bind to lead and allow it to be excreted in the urine.

But no one knows if that therapy can ease symptoms of gout in people with mildly elevated lead levels

"There are medications that can leach lead out of the blood," Krishnan said. "But they are not approved to treat gout. And they are not without risks."

Chelation therapy can, for instance, damage the kidneys permanently.

So even if someone with gout were found to have relatively elevated lead levels, no specific treatment recommendations can be made, Krishnan said.

Both he and Sehgal said the findings' main importance have to do with bigger-picture public health.

"I think policymakers should consider these data" in any future review of the lead threshold for adults, Krishnan said.

The U.S. Centers for Disease Control and Prevention recently lowered the maximum acceptable lead level for children - from 10 mcg/dL to 5 mcg/dL. The threshold for children is lower because their developing brains are particularly vulnerable to damage from lead.

Sehgal said he thinks lower thresholds for adults are feasible. He noted that in Germany, the standards are 7 mcg/dL for women and 9 mcg/dL for men.

SOURCE: http://bit.ly/MnBiCA Annals of Internal Medicine, August 21, 2012.