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Clinical validation of controlled grass pollen challenge in the Environmental Exposure Unit (EEU).

Ellis AK, Steacy LM, Hobsbawn B, Conway CE, Walker TJ - Allergy Asthma Clin Immunol (2015)

Bottom Line: Two separate groups allowed for the exploration of lower vs. higher pollen concentrations and subsequent effects on symptoms. 78 participants were screened, of whom 39 were eligible and attended the 2x3h EEU visits, plus 8 non-atopic controls.In comparison, mean TSS, TNSS and PNIF values in the lower pollen concentration (2500 grains/m3) group were only 13.3, 7.6, and 82 L/min, respectively.This study provides clinical validation of the ability to generate allergic rhinoconjunctivitis symptoms amongst grass-allergic individuals in the EEU.

View Article: PubMed Central - PubMed

Affiliation: Division of Allergy & Immunology, Department of Medicine, Queen's University, Kingston, ON Canada ; Allergy Research Unit, Kingston General Hospital, 76 Stuart Street, Kingston, ON K7L 2 V7 Canada.

ABSTRACT

Rationale: The Environmental Exposure Unit (EEU), a controlled allergen exposure model of allergic rhinitis (AR), has traditionally utilized ragweed pollen. We sought to clinically validate the use of grass pollen in the EEU.

Methods: Healthy volunteers with a history of AR symptoms during grass pollen season and supportive skin test responses attended the EEU for 3 hrs of rye grass pollen exposure (Lolium Perenne). Non-atopic controls were also recruited. Participants assessed individual rhinoconjunctivitis symptoms to generate Total Nasal Symptom Score (TNSS; max 12) and Total Symptom Score (TSS; max 24) and recorded Peak Nasal Inspiratory Flow (PNIF) q30min while in the EEU. Participants returned the following day for an additional 3 hrs of pollen exposure. Two separate groups allowed for the exploration of lower vs. higher pollen concentrations and subsequent effects on symptoms.

Results: 78 participants were screened, of whom 39 were eligible and attended the 2x3h EEU visits, plus 8 non-atopic controls. Mean TSS, TNSS and PNIF values amongst participants in the higher pollen concentration group (target 3500 grains/m3) after the first 3 hr exposure were 18.9, 9.7 and 68 L/min, respectively. In comparison, mean TSS, TNSS and PNIF values in the lower pollen concentration (2500 grains/m3) group were only 13.3, 7.6, and 82 L/min, respectively. The subsequent day of pollen exposure did not appreciably alter the maximal TSS/TNSSs, but rather resulted in a more rapid onset of symptomatology, with higher mean scores at the 30 min, 60 min and 90 min timepoints. The non-atopic controls remained asymptomatic.

Conclusions: This study provides clinical validation of the ability to generate allergic rhinoconjunctivitis symptoms amongst grass-allergic individuals in the EEU.

No MeSH data available.


Related in: MedlinePlus

Total Symptom Scores (TSS) were higher in the higher pollen concentration group (HPC) than the lower pollen concentration group (LPC) after three hours of pollen exposure. The second day of pollen exposure in both groups resulted in similar peak TSSs after 3 hours of exposure as the day previous, but generated a more rapid increase in TSS.
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Fig3: Total Symptom Scores (TSS) were higher in the higher pollen concentration group (HPC) than the lower pollen concentration group (LPC) after three hours of pollen exposure. The second day of pollen exposure in both groups resulted in similar peak TSSs after 3 hours of exposure as the day previous, but generated a more rapid increase in TSS.

Mentions: Mean TSS and TNSS scores obtained in both the higher (target 3500 grains/m3) and lower (2500 grains/m3) pollen concentration groups over both days of exposure are summarized in Figures 3 and 4. Mean TSS and TNSS amongst allergic participants in the higher pollen concentration group after the first 3 hr exposure (i.e. at hour 3) were 18.9 (SD = 2.7) and 9.7 (SD = 5.1), respectively. In comparison, mean TSS and TNSS values in the lower pollen concentration group were only 13.3 (SD = 5.9) and 7.6 (SD = 2.6), respectively.Figure 3


Clinical validation of controlled grass pollen challenge in the Environmental Exposure Unit (EEU).

Ellis AK, Steacy LM, Hobsbawn B, Conway CE, Walker TJ - Allergy Asthma Clin Immunol (2015)

Total Symptom Scores (TSS) were higher in the higher pollen concentration group (HPC) than the lower pollen concentration group (LPC) after three hours of pollen exposure. The second day of pollen exposure in both groups resulted in similar peak TSSs after 3 hours of exposure as the day previous, but generated a more rapid increase in TSS.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4316395&req=5

Fig3: Total Symptom Scores (TSS) were higher in the higher pollen concentration group (HPC) than the lower pollen concentration group (LPC) after three hours of pollen exposure. The second day of pollen exposure in both groups resulted in similar peak TSSs after 3 hours of exposure as the day previous, but generated a more rapid increase in TSS.
Mentions: Mean TSS and TNSS scores obtained in both the higher (target 3500 grains/m3) and lower (2500 grains/m3) pollen concentration groups over both days of exposure are summarized in Figures 3 and 4. Mean TSS and TNSS amongst allergic participants in the higher pollen concentration group after the first 3 hr exposure (i.e. at hour 3) were 18.9 (SD = 2.7) and 9.7 (SD = 5.1), respectively. In comparison, mean TSS and TNSS values in the lower pollen concentration group were only 13.3 (SD = 5.9) and 7.6 (SD = 2.6), respectively.Figure 3

Bottom Line: Two separate groups allowed for the exploration of lower vs. higher pollen concentrations and subsequent effects on symptoms. 78 participants were screened, of whom 39 were eligible and attended the 2x3h EEU visits, plus 8 non-atopic controls.In comparison, mean TSS, TNSS and PNIF values in the lower pollen concentration (2500 grains/m3) group were only 13.3, 7.6, and 82 L/min, respectively.This study provides clinical validation of the ability to generate allergic rhinoconjunctivitis symptoms amongst grass-allergic individuals in the EEU.

View Article: PubMed Central - PubMed

Affiliation: Division of Allergy & Immunology, Department of Medicine, Queen's University, Kingston, ON Canada ; Allergy Research Unit, Kingston General Hospital, 76 Stuart Street, Kingston, ON K7L 2 V7 Canada.

ABSTRACT

Rationale: The Environmental Exposure Unit (EEU), a controlled allergen exposure model of allergic rhinitis (AR), has traditionally utilized ragweed pollen. We sought to clinically validate the use of grass pollen in the EEU.

Methods: Healthy volunteers with a history of AR symptoms during grass pollen season and supportive skin test responses attended the EEU for 3 hrs of rye grass pollen exposure (Lolium Perenne). Non-atopic controls were also recruited. Participants assessed individual rhinoconjunctivitis symptoms to generate Total Nasal Symptom Score (TNSS; max 12) and Total Symptom Score (TSS; max 24) and recorded Peak Nasal Inspiratory Flow (PNIF) q30min while in the EEU. Participants returned the following day for an additional 3 hrs of pollen exposure. Two separate groups allowed for the exploration of lower vs. higher pollen concentrations and subsequent effects on symptoms.

Results: 78 participants were screened, of whom 39 were eligible and attended the 2x3h EEU visits, plus 8 non-atopic controls. Mean TSS, TNSS and PNIF values amongst participants in the higher pollen concentration group (target 3500 grains/m3) after the first 3 hr exposure were 18.9, 9.7 and 68 L/min, respectively. In comparison, mean TSS, TNSS and PNIF values in the lower pollen concentration (2500 grains/m3) group were only 13.3, 7.6, and 82 L/min, respectively. The subsequent day of pollen exposure did not appreciably alter the maximal TSS/TNSSs, but rather resulted in a more rapid onset of symptomatology, with higher mean scores at the 30 min, 60 min and 90 min timepoints. The non-atopic controls remained asymptomatic.

Conclusions: This study provides clinical validation of the ability to generate allergic rhinoconjunctivitis symptoms amongst grass-allergic individuals in the EEU.

No MeSH data available.


Related in: MedlinePlus