Table 1.

Ascertaining modified Dutch Lipid Clinic Network criteria for heterozygous FH: use of structured data sets and natural language processing

Criteria	Method	Points
Family history: first-degree relative with hypercholesterolemia or premature ASCVD	NLP of PPI and clinical notes	1
Personal history of premature coronary heart disease	Two ICD-9-CM and/or CPT-4 codes	2
Personal history of premature cerebrovascular or peripheral arterial disease		1
Presence of tendon xanthomas	NLP of clinical notes	6
Presence of corneal arcus before age 45 years		4
LDL-C, >325 mg/dL	Laboratory data sets	8
LDL-C, 251–325 mg/dL		5
LDL-C, 191–250 mg/dL		3

ASCVD, atherosclerotic cardiovascular disease, including coronary heart disease (CHD), cerebral (CVD) or peripheral arterial disease (PAD); ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification; CPT, current procedural terminology codes; LDL-C, low-density lipoprotein cholesterol; NLP, Natural Language Processing; PPI, patient provided information.

Premature ASCVD cases were defined if two or more relevant diagnosis codes were present in EHR before age 55 years in men and 65 years in women. Assigned codes were evaluated at discharge from each encounter during the prevalence period. CHD was defined as angina pectoris, myocardial infarction, coronary atherosclerosis/chronic ischemic heart disease, percutaneous coronary revascularization, coronary bypass surgery, cerebrovascular disease included ischemic stroke, transient ischemic attack, carotid artery disease, carotid revascularization, and peripheral arterial disease: lower extremity arterial disease, surgical and percutaneous vascular interventions. Qualifying LDL-C was scored at the index date. Because all patients had LDL-C ≥190 mg/dL, according to the DLCN criteria, all these patients had a minimum score of 3 points. All other parameters were extracted within the prevalence period: June 21, 1993, till December 31, 2014.