SEATTLE-- Patients with nonallergic rhinitis report significantly less sneezing and nasal congestion but greater sensitivity to cold air and temperature changes than do those with allergic rhinitis, according to data presented at the annual meeting of the American College of Allergy, Asthma, & Immunology in Seattle. Other highlights of the meeting included findings that an educational intervention can improve influenza vaccination rates among staff and that patients with severe asthma appear to be at greater risk for psychiatric morbidity.

Patients with nonallergic rhinitis appear to be older and to experience different symptoms than do patients with allergic rhinitis, according to new findings. In a Veterans Affairs population, patients with nonallergic rhinitis reported significantly less sneezing and nasal congestion than did allergic rhinitis patients. In addition, they were more likely to react to cold air, temperature changes, and strong odors or fumes (Figure 1).

To identify characteristics that could help physicians distinguish between allergic and nonallergic rhinitis during the history taking, Kumar R. Patel, MD, and fellow researchers at the University of Medicine and Dentistry of New Jersey, Newark, conducted a one-year retrospective review of patients who presented with rhinitis complaints. They found significant differences in symptoms and in response to nonspecific irritants. In addition, patients with nonallergic rhinitis were older than the other patients.

Teaching residents about the importance of vaccination for preventing the transmission of influenza can significantly improve vaccination rates among this population. In July 1998, Jeffrey M. Turnbull, MD, and colleagues developed and implemented a 10-minute educational intervention, which was given to residents at the University of Ottawa before the vaccination season. Residents who did not attend the educational session were considered controls.

One year later, subjects were asked to complete a follow-up survey. Among the residents who participated in the educational intervention, vaccination rates rose significantly from 1997 to 1998 (28% to 59%). In comparison, only 25% of the control group were vaccinated in 1998.

In addition, residents' knowledge of influenza vaccination significantly improved. For example, before the intervention, only 67% of residents knew that immunocompromised patients should be vaccinated, whereas after the intervention, 95% of residents knew this information. Similarly, residents' knowledge that family members of high-risk patients should be vaccinated improved from 42% to 91%.

Psychiatric morbidity may be more common in patients with asthma than previously thought. Although high-dose inhaled corticosteroids may improve pulmonary function and physical quality of life, they appear to have negative effects on patients' mental well-being, reported Savithri Bonala, MD, and colleagues.

The researchers assessed psychiatric symptoms and quality of life in 51 asthmatic outpatients. The patients were stratified by asthma symptom severity (mild, mild-moderate, moderate, moderate-severe, severe) and by inhaled corticosteroid dosage (none, low, medium, high). Anxiety and depressive symptoms were prevalent in this population, particularly among the patients with severe asthma. High corticosteroid doses and asthma severity were significantly related to all measurements of psychiatric morbidity. In addition, high doses correlated directly with peak flow and forced expiratory volume in one second, but they were inversely related to general quality of life.

People who own dark-colored cats are significantly more likely than those with light-colored cats or no cats to have severe or moderate allergic symptoms, according to new findings. Sumera Hussain, MD, and colleagues at Long Island College Hospital in Brooklyn, New York, conducted a case-control study to assess the association between the color of cat hair and the severity of allergic rhinitis symptoms.

Of the 321 subjects enrolled in the study, 8% reported severe allergic symptoms, 25% moderate symptoms, 38% mild symptoms, and 29% no symptoms. The researchers found that patients with dark-colored cats were two to four times more likely to report severe or moderate symptoms than were patients with light-colored or no cats; there were no significant differences in symptom severity between those with light-colored cats and those with no cats.

Interestingly, the patients who allowed their dark-colored cats in the bedroom were markedly more likely to experience moderate or severe symptoms than were those with no cats. Conversely, the patients who did not allow their dark-colored cats in the bedroom had no significant increase in the risk of moderate or severe symptoms.

Air pollution and industrial chemicals have been linked with increased airway disease, but the causes of the increased risk have been unclear. New research suggests that changes in the human airways may occur following exposure to pollution and account for the increased morbidity.

Anthony J. Frew, MD, et al in Sweden and London studied the effects of diesel exhaust particles on human airways. Volunteers were exposed to diluted diesel exhaust at concentrations comparable to those found in occupational settings, such as bus garages and North Sea ferries. Subjects were exposed to air or diesel exhaust for one hour in a specially built chamber. Six hours after exposure, they underwent fiberoptic bronchoscopy, and samples were obtained for analysis.

"No significant effect of diesel exhaust was found on lung function at this concentration. However, the exposure induced a marked neutrophilic response in normal human airways and peripheral blood, which might explain the morbidity reported in studies on particulate pollution," Dr. Frew said.

--Deborah L. O'Connor