Evaluation of the Small Airways in Patients with Chronic Obstructive Pulmonary Disease and Alpha-1 Antitrypsin Deficiency

Figures & data

Table 1 Variations of Mutations of the SERPINA1 Gene of Patients Included in the Study

Gene Mutation Variations of SERPINA1	Number of Patients
PiMS	8
PiMZ	3
PiZZ	4
PiNull	1

Notes: SERPINA, serine protease inhibitor; Pi, protease inhibitor; Null, null mutation, which is characterized by the absence of production of any amount of alpha-1 antitrypsin.

Figure 1 Recruitment flowchart.

Table 2 Evaluation of Clinical and Functional Differences Between Groups of Patients with COPD with and without Mutation of the Alpha-1 Antitrypsin Gene

Variables	Mutation	N	Average	Standard Deviation	P value
Age (years)	With	16	65.56	7.55	0.586
	Without	45	66.78	7.65
Packs/year	With	16	28.06	25.10	0.001
	Without	44	75.57	56.11
FEV1/FVC	With	16	50.96	12.43	0.412
	Without	45	53.55	10.14
FEV1%	With	16	56.81	21.49	0.486
	Without	45	61.71	19.09
FVC%	With	16	86.31	16.64	0.408
	Without	45	91.60	19.58
TLC%	With	14	124.86	31.75	0.670
	Without	42	122.57	46.02
RV%	With	14	179.07	72.39	0.264
	Without	42	166.90	109.00
RV/TLC%	With	14	140.79	33.22	0.272
	Without	42	131.71	26.42
DLCO%	With	15	85.53	30.29	0.141
	Without	45	72.76	18.65
KCO%	With	16	96.63	19.95	0.235
	Without	45	88.56	24.09

Abbreviations: FEV1/FVC, forced expiratory volume in the first second/forced vital capacity; FEV1%, forced expiratory volume in the first second percentage of predicted; FVC%, forced vital capacity percentage of predicted; TLC%, total lung capacity percentage of predicted; RV%, residual volume percentage of predicted; DLCO%, diffusing capacity of the lungs for carbon monoxide percentage of predicted; KCO%, Krogh’s constant the value calculated from DLCO/VA (diffusing capacity of the lungs for carbon monoxide/alveolar volume).

Table 3 Relationship Between Closure Volume (%) and Smoking Load in Patients with Alpha-1 Antitrypsin Mutation

Number of Packs/Year	Closure Volume (%)	P value
5	7.42	<0.001
10	7.01	<0.001
15	6.60	<0.001
20	6.19	<0.001
25	5.78	0.001
30	5.37	0.002
40	4.54	0.026
60	2.90	0.524

Figure 2 Ability of the phase III slope to predict differences in severity between those with mild, moderate, and severe/very severe COPD. *p<0.01 **p<0.001.

Figure 3 Ability of ΔN2 750–1250 mL (%) to predict differences in severity between those with mild and moderate COPD. *p<0.01.

Figure 4 Inverse correlations between number of packs/year and closure volume (%) in patients with a mutation of the alpha-1 antitrypsin deficiency gene. Coefficient of determination (R2) = 24.9%.