Table S2.

Methods for stratifying subjects by symptom status

Symptomatic patients defined by the presence of any of these secondary ICD-9 codes
413.xx	Angina
780.2x	Syncope
780.4	Dizziness and giddiness
785.1	Palpitations
786.0	Dyspnea and respiratory abnormalities
786.02	Orthopnea
786.03	Apnea
786.05	Shortness of breath
786.07	Wheezing
786.5x	Chest pain

Notes: Results also stratified by asymptomatic and symptomatic disease status; asymptomatic patients defined by not having an ICD-9 code listed above.

Abbreviation: ICD, International Classification of Diseases.