Table 1—

Characteristics of participants in the Boston Early-Onset Chronic Obstructive Pulmonary Disease Study

Characteristics	Probands	Family members
Subjects	72	516
Age yrs	47.7±5.3	46.5±18.5
Female sex	54 (75.0)	276 (53.5)
FEV₁ % pred	17.4±6.4	83.0±20.8^¶
BMI kg·m^-2	24.4±5.9⁺	27.1±5.8^¶
Smoking pack-yrs	38.9±21.6	20.5±25.7
Ever-smoker	69 (95.8)	342 (66.3)
Current smoker	7 (9.7)	168 (32.6)
Doctor diagnosed “heart trouble”	10 (13.9)	86 (16.7)^¶
Current corticosteroid use
Inhaled	61 (84.7)	28 (5.5)^¶
Oral	26 (36.1)	6 (1.2)^¶
Current theophylline use	38 (52.8)	11 (2.2)^¶
CRP mg·L^-1#	2.87±3.29⁺	1.71±3.61^¶

Data are presented as n, mean±sd or n (%). FEV₁: forced expiratory volume in one second; % pred: % predicted; BMI: body mass index; CRP: C-reactive protein. ^#: CRP level reported as geometric mean (±sd); ^¶: n<516; ⁺: n<72.