Estimating the Prevalence of AATD Patients in the UK to Identify Underdiagnosis and Determine the Eligibility for Potential Augmentation Therapy

Figures & data

Table 1 Characteristics of Patients from the THIN Database

Characteristic	Category	Control N=473095	COPD N=254911	AATD N=1754
Age (years)		68 [59–76]	69 [60–77]	59 [50–68]
Age (years)	16–25	989 (0.2)	494 (0.2)	1 (0.1)
	26–36	2997 (0.6)	1427 (0.6)	42 (2.4)
	36–45	16,850 (3.6)	7568 (3.0)	205 (11.7)
	46–55	59,845 (12.6)	28,356 (11.1)	445 (25.4)
	56–65	123,679 (26.1)	62,572 (24.5)	518 (29.5)
	>65	268,735 (56.8)	154,494 (60.6)	543 (31.0)
Sex	Female	230,423 (48.7)	124,043 (48.7)	889 (50.7)
	Male	242,672 (51.3)	130,868 (51.3)	865 (49.3)
Ethnicity	White	218,084 (98.4)	116,622 (97.4)	750 (97.4)
	South Asian	2015 (0.9)	1584 (1.3)	14 (1.8)
	Black	797 (0.4)	699 (0.6)	2 (0.3)
	Mixed race	536 (0.2)	553 (0.5)	2 (0.3)
	Others	154 (0.1)	278 (0.2)	2 (0.3)
COPD	Yes	NA	254911 (100.0)	1255 (71.6)
AATD code type	AAT genotype	NA	NA	53 (3.0)
	AAT hepatitis	NA	NA	31 (1.8)
	AAT phenotype	NA	NA	1136 (64.8)
	AATD	NA	NA	534 (30.4)
Smoking status	Current	70,686 (15.8)	93,561 (37.4)	484 (27.9)
	Ex	128,531 (28.7)	116,416 (46.6)	685 (39.5)
	Never	248,165 (55.5)	40,045 (16.0)	563 (32.5)
Pack years smoked		23 [10–38]	34 [19–50]	16 [11–35]
FEV1 (litres)		2.25 [1.78–2.79]	1.59 [1.15–2.10]	1.66 [1.18–2.27]
FEV1 (% predicted)		89 [76–101]	62 [48–77]	60 [42–77]
FEV1/FVC		0.77 [0.71–0.83]	0.63 [0.53–0.73]	0.62 [0.48–0.72]

Notes: Data is shown as median [interquartile range] or n (%).

Abbreviations: AAT(D), alpha-1 antitrypsin (deficiency); COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity.

Table 2 Characteristics of Patients from the Birmingham Registry

Characteristic	Category	Value
Age (years)		51 [42–59]
Age (years)	16–25	17 (2.0)
	26–36	60 (7.1)
	36–45	207 (24.6)
	46–55	265 (31.4)
	56–65	211 (25.0)
	>65	83 (9.8)
Sex	Female	426 (45.2)
	Male	516 (54.8)
Ethnicity	White	748 (99.7)
	South Asian	0 (0)
	Black	1 (0.1)
	Mixed race	0 (0)
	Others	1 (0.1)
COPD	Yes	728 (88)
Pack years smoked		19 (11–28)
Smoking status	Current	69 (7.8)
	Ex	601 (68.4)
	Never	99 (13.5)
FEV1 (litres)		1.52 [1.01–2.33]
FEV1% predicted		46 [33–73]
FEV1/FVC		0.39 [0.30–0.56]
TLCO (mmol/min/kPa)		5.68 [4.20–7.36]
KCO (mmol/min/kPa/L)		1.02 [0.81–1.32]
mMRC score	0	128 (17.5)
	1	137 (18.7)
	2	180 (24.6)
	3	188 (25.7)
	4	99 (13.5)

Notes: Data is shown as median [interquartile range] or n (%).

Abbreviations: see Table 1 and in addition, TLCO, diffusing capacity for carbon monoxide; KCO, transfer coefficient for carbon monoxide; mMRC, Modified Medical Research Council Dyspnea Scale.

Figure 1 Prevalence of symptoms and lung disease according to age in the Birmingham AATD registry.

Figure 2 Prevalence of smoking status according to age and index status in the Birmingham AATD registry. (a) Symptomatic index lung (n=585); (b) Asymptomatic index lung (n=71); (c) Symptomatic non-index lung (n=74); (d) Asymptomatic non-index lung (n=58).

Table 3 Age Distribution of Patients in the UK Population, THIN & Birmingham (Bham) Cohorts After Exclusion of Liver Index Cases

Age	AATD Bham Cohort	AATD THIN Cohort	COPD THIN Cohort	UK Census 2011
16–25	0	0	0	12
26–36	4	2	1	13
36–45	22	12	3	14
46–55	35	25	11	14
56–65	28	30	25	12
>65	12	31	61	16

Notes: The table shows % of patients in each population falling into each age category. Note that UK census does not sum to 100% because patients aged<16 were excluded.