This study compared obese and non-obese asthma patients to determine if obesity is associated with a distinct asthma phenotype. The study found that obese asthma patients had poorer asthma control despite similar lung function and airway responsiveness. Obese patients also had lower lung volumes and higher systemic inflammation markers. This suggests obesity may be linked to a different asthma phenotype characterized by poorer control and increased inflammation.

1. OBESITY & ASTHMA A Specific Phenotype? Andrea Lessard, BSc; Helene Turcotte, MSc; Yum Cormier, MD; and Louis-Philippe Boulet, MD, FCCP Source: CHEST – Official Publication of the American College of Chest Physician Vol.134, No.2, p317-323, 2008

13. Table 1 – Demographic & Medical Characteristics 0.78 ± 0.06 0.78 ± 0.07 σ waist-hip ratio 77.7 ± 8.9 79.0 ± 7.2 σ waist circ. 17 (77.3) 22 (100) Subj. w/ atopy 22.8 ± 2.4 23.3 ±1.8 BMI 11 (50) 7 (31.2) Ex. smokers 1 (4.5) 0 Subj. w/ GERD 0 0 Subj. w/ DM 2 2 (9) 0 Subj. w/ HPN 17.5 ± 12.1 18.6 ± 13.8 Asthma duration, yr 22 (100) 15 (68) Female gender 43.7 ± 13.3 32.5 ± 10.0 Age SABAs + ICS (n=22) SABAs (n=22) VARIABLES NON-OBESE

14. 15 (68.2) 21 (95.5) Subj. w/ atopy 107.3 ± 12.4 109.5 ± 16.2 σ waist circ. 0.88 ± 0.09 0.88 ± 0.09 σ waist-hip ratio 37.0 ± 5.8 37.2 ± 5.7 BMI 8 (36.4) 6 (27.3) Ex. smokers 3 (13.6) 2 (9) Subj. w/ GERD 2 (9) 1 (4.5) Subj. w/ DM 2 4 (18) 2 (9) Subj. w/ HPN 24.7 ± 13.6 16.7 ± 8.7 Asthma duration, yr 22 (100) 15 (68) Female gender 44.1 ± 13.5 36.5 ± 13.0 Age SABAs + ICS (n=22) SABAs (n=22) VARIABLES OBESE

18. Table 2 – Spirometry, Lung Volumes, & Methacholine Test Results 106 ± 20 108 ± 25 σ IC % predicted 117 ± 33 108 ± 44 σ ERV % predicted 1.03 (0.66-1.61) 1.32 (0.79-2.20) PC 20 mg/mL 5.7 ± 4.6 6.5 ± 7.0 σ change % predicted reversibble FEV1 119 ± 28 125 ± 33 σ RV % predicted 115 ± 15 113 ± 18 σ TLC % predicted 56 ± 24 73 ± 23 σ FEF 25-75% % predicted 88 ± 11 92 ± 10 σ FEV/FVC 101 ± 15 111 ± 15 σ FVC % predicted 90 ± 17 98 ± 13 σ FEV1 % predicted SABAs + ICS (n=22) SABAs (n=22) VARIABLES NON-OBESE

19. 0.96 (0.55-1.68) 1.36 (0.77-1.61) PC 20 mg/mL 6.3 ± 5.6 4.9 ± 5.2 σ change % predicted reversibble FEV1 127 ± 24 124 ± 24 σ IC % predicted 67 ± 61 78 ± 36 σ ERV % predicted 117 ± 25 90 ± 23 σ RV % predicted 109 ± 12 104 ± 13 σ TLC % predicted 50 ± 22 79 ± 25 σ FEF 25-75% % predicted 90 ± 12 94 ± 7 σ FEV/FVC 92 ± 13 111 ± 18 σ FVC % predicted 81 ± 16 100 ± 18 σ FEV1 % predicted SABAs + ICS (n=22) SABAs (n=22) VARIABLES OBESE

22. Table 3: Differential Cell Count in Induced Sputum 1.9 (2.1) 10.5 (17.1) Metachromatic cells 40.9 (17.1) 31.6 (21.8) Neutrophils 1.5 (1.3) 1.3 (0.9) Lymphocystes 40.6 (19.4) 54.5 (30.1) Macrophages 15.2 (19.6) 2.6 (3.7) Eosinophils SABAs + ICS SABAs VARIABLES NON-OBESE

23. 3.2 (4.1) 3.6 (3) Metachromatic cells 41.5 (26.7) 48.6 (21.3) Neutrophils 1.5 (1.0) 1.3 (1.2) Lymphocystes 48.7 (23.9) 42.1 (19.8) Macrophages 5.1 (8.8) 4.6 (12.9) Eosinophils SABAs + ICS SABAs VARIABLES OBESE

24. 2.4 ± 3.4 mg/L 4.3 ± 3.2 mg/L σ serum CRP (p=0.001) 3.1 ± 0.6 g/L 3.7 ± 0.7 g/L Serum level of Fibrinogen (p=0.0002) 219 ± 245 IU/mL 216 ± 367 IU/mL Serum IgE (p=0.96) NON-OBESE OBESE

36. thank you!