People with emphysema or chronic bronchitis may be at higher than average risk for a painful rash known as shingles, a study published Tuesday suggests.
The shingles rash is caused by the same virus that causes chickenpox. After a person has had chickenpox, the virus hides in the body's nerve tissue, where it can become active again later in life.
Shingles is most common after the age of 50, and in those whose body can't fight off illness as well as usual because their immune system isn't working properly. Many cases occur in patients taking immune-suppressing medications or who have cancer.
But it has not been clear whether the risk is elevated for people with chronic obstructive pulmonary disease (COPD), a group of serious lung diseases - such as emphysema and chronic bronchitis -- that make it hard to breathe.
In the new study, researchers in Taiwan kept track of nearly 8,500 COPD patients, age 50 and up. They found that on average, every year for 10 years, 16 of every thousand patients developed shingles. But among nearly 34,000 COPD-free adults the same age, only 9 of every thousand developed shingles every year.
When the researchers considered other factors -- like people's overall health and income -- COPD itself was linked to a two-fold increase in the risk of shingles.
While COPD is a lung disease, it also involves widespread inflammation in the body and disruption of some parts of the immune system, explained Dr. Ya-Wen Yang of Taipei Medical University, the lead researcher on the study.
That, Yang told Reuters Health in an email, may explain the higher vulnerability to shingles.
The findings, reported in the Canadian Medical Association Journal, are also in line with past studies that have linked other inflammatory conditions -- like rheumatoid arthritis and inflammatory bowel disease -- to a higher than average shingles risk.
Shingles has no cure, but there are antiviral drugs that can lessen symptoms and speed recovery, especially if they're taken soon after the rash appears.
There is a one-time vaccine against shingles that reduces the risk of developing the condition in the first place. It is recommended for all adults age 60 and older -- the only group so far in which the vaccine has been tested adequately.
"Because shingles is frequently complicated with chronic pain, leading to reduced quality of life, we suggest COPD patients discuss with their doctor if they are appropriate for shingles vaccination," Yang said.
The vaccine, called Zostavax, was approved by the U.S. Food and Drug Administration in 2006, but the majority of eligible patients have not received it. Expense might be a large factor: the vaccine is covered by Medicare Part D prescription drug plans but not by regular Medicare policies that cover only doctor visits and hospital stays. For people whose insurance doesn't cover it, the vaccine can cost up to $200.
Another possible reason for under-use of the vaccine is that while doctors who treat children are accustomed to prescribing immunizations, doctors treating adults are not. In an interview with Reuters Health last month, Dr. Michael Oxman at the University of California, San Diego, who has been involved in studies of the vaccine, said, "The human cost of (shingles) is enormous." But, he added, "Adult medicine is really geared toward diagnosis and treatment of existing diseases. The adult medical community is just not as attuned to preventing disease ... as pediatricians are." (See Reuters Health story of January 11, 2011.)
According to the U.S. Centers for Disease Control and Prevention, about one-third of people with shingles develop complications, most commonly long-lasting nerve pain - called post-herpetic neuralgia - that can go on for months or even years after the rash has healed.
In the U.S. it's estimated that one-quarter to one-third of adults will develop shingles at some point.