THURSDAY, March 4 (HealthDay News) -- Asthma may affect more than your ability to breathe, it may also make you more prone to developing psychological problems, new research suggests.

People with asthma are more than twice as likely to have depression or anxiety as people who don't have the chronic airway disease, according to a report in the March issue of the journal Chest.

To make matters worse, the study authors found that when rates of serious psychological distress went up, health-related quality-of-life scores went down.

"The prevalence of serious psychological distress was 2.5 times higher among adults with asthma, and as serious psychological distress increased, health-related quality went down. So, asthma makes quality of life worse and serious psychological distress makes quality of life worse, and together they synergistically make quality of life even worse," said study senior author Dr. David Callahan, a medical epidemiologist at the U.S. Centers for Disease Control and Prevention and the U.S. Public Health Service in Atlanta.

Study author Emeka Oraka said these findings may apply to other chronic diseases, such as diabetes, and that serious psychological distress may make it harder for people to manage these diseases properly.

"Any kind of mental distress impedes your ability to manage the disease well, whether it's asthma, diabetes or something else," said Oraka, who's an Oak Ridge Institute for Science and Education fellow at the CDC.

Oraka noted that the findings should raise a red flag for clinicians. "Serious psychological distress is a powerful predictor of quality of life, and even more so in the presence of chronic illness," he said. "Don't disregard the importance of mental health in the quality of life of patients with chronic illness."

For the study, the researchers reviewed data from 186,738 adults who had participated in the U.S. National Health Interview Survey between 2001 and 2007. From this database, they discovered that the rate of asthma was 7 percent.

Among all of the study participants, the average prevalence of serious psychological distress was 3 percent, but in people with asthma, the rate of serious psychological distress was 7.5 percent, the researchers found.

Adults with asthma who had other chronic conditions, a history of smoking or alcohol use, and those with a lower socioeconomic background had a greater risk of having serious psychological distress, according to the study.

Oraka said that the study wasn't able to tease out whether asthma is a cause of serious psychological distress or whether asthma medications may make serious psychological distress more likely, or whether people with serious psychological distress may be more likely to have asthma or to report having asthma.

"This study found an association, but no causation," Oraka said.

Dr. Jennifer Appleyard, chief of allergy and immunology at St. John Hospital and Medical Center in Detroit, said it was troubling to see that "the prevalence of anxiety or mental distress is higher in asthmatics than normal, and this is something we need to look for and try to prevent and address it."

She said the subject definitely warrants further study, and that she would like to see a study that assesses asthma more objectively. In the current study, asthma was identified by the study participants, who were asked if a doctor had ever told them they had asthma, and if they still had asthma.

But, "even if you have mild asthma, it's definitely an anxiety-provoking diagnosis," Appleyard added.

"As with any chronic disease, asthma needs to be managed carefully by the patients, and serious psychological distress can get in the way of people managing their own asthma," explained Callahan. "Clinicians need to ask about psychological symptoms in people with asthma, and they need to treat both psychological distress and asthma."

More information

To read more on asthma and depression, visit the American Academy of Allergy, Asthma & Immunology  .

MONDAY, March 1 (HealthDay News) -- The rise in temperatures associated with climate change might have an unexpected consequence: more allergies among more people.

New research from Italy suggests that higher temperatures are lengthening the pollen season for some plants and trees, increasing the pollen load they produce and causing a rise in the number of people who are developing allergies to certain pollens.

"The increase of global radiation determines an advance [of pollen season] and an increased period of exposure to the pollens," said study author Dr. Renato Ariano, director of the allergy service at Bordighera Hospital in Italy. Ariano said the increased exposure to pollen can cause more people who are susceptible to allergy to actually develop pollen allergies.

Ariano was scheduled to present the findings Monday in New Orleans at the annual meeting of the American Academy of Allergy, Asthma & Immunology.

For nearly 30 years, Ariano and his colleagues have been recording pollen counts, the length of pollen seasons and the prevalence of people sensitized to five major pollens in the Bordighera region of Italy -- birch, cypress, olive, grass and parietaria, a common plant in that region.

The Bordighera region is in western Liguria, on the Mediterranean Sea at the border of Italy and France, said study author Dr. Giovanni Passalacqua, an assistant professor of allergy and respiratory diseases at Genoa University in Italy. Bordighera "has a very mild Mediterranean climate and is surrounded by a rural landscape where flowers and olives are cultivated," he said.

Between 1981 and 2007, the researchers noted an earlier start for pollen season. In the case of parietaria, the pollen season began about 80 days sooner at the end of the study period than it did at the beginning. For olive trees, the pollen season began about 30 days sooner, Passalacqua said.

At the same time, the researchers also tested area residents, using skin prick testing to assess the levels of sensitization to the five pollens. If someone reacts on a skin prick test, they're said to be sensitized to that substance. However, being sensitized to a substance in an allergy test doesn't always translate to noticeable symptoms, though there's often a correlation between the two.

"We observed a constant increase of the percentage of subjects sensitized to olive, parietaria and cypress, whereas the percentage of subjects sensitized to dust mites remained unchanged over 27 years," Passalacqua said.

Estelle Levetin, a professor of biology who chairs the biological sciences faculty at the University of Tulsa in Oklahoma said that "the data already show that pollen seasons could be longer and pollen levels could be higher, and although this needs more study, it may be that the pollen grain is becoming more allergenic when plants are grown with higher carbon dioxide levels."

This means that people with allergies might need to start taking allergy medications earlier and continue them for a longer period of time, Levetin said. Anyone who feels that their allergies are starting earlier should discuss this with their doctor, she said.

More information

The American Academy of Allergy, Asthma and Immunology offers a city by city look at pollen levels  .