title: Prevalence, clinical features, and prognosis of patients with extremely low high-density lipoprotein cholesterol.
abstract: Little data exist on the clinical features of patients with an extremely low level of high-density lipoprotein (HDL) cholesterol (<20 mg/dL).
  
  
  
  To assess the clinical characteristics of Japanese patients with extremely low HDL cholesterol levels.
  
  
  
  In this observational study of 429 patients with extremely low HDL cholesterol levels among 43,368 subjects whose HDL cholesterol was measured for any reason at Kanazawa University Hospital from April 2004 to March 2014, we investigated the presence of coronary artery disease, chronic kidney disease, the potential causes of reduced HDL cholesterol, their prognosis, and the cause of death.
  
  
  
  Most patients (n = 425, 99%) exhibited secondary causes, including malignancies (n = 157, 37%), inflammatory diseases (n = 219, 51%), or other critical situations, such as major bleeding (n = 58, 14%). During the median 175-day follow-up period, 106 patients died. The causes of death in 80 (75%) patients were malignancies, inflammatory diseases, or major bleeding, in contrast to a relatively low incidence of death from atherosclerotic cardiovascular disease (n = 10, 10%). Multiple regression analysis showed that the presence of malignancy and HDL cholesterol was independently associated with death, in addition to age. The cumulative survival curve revealed that patients with an HDL cholesterol of <15 mg/dl, determined using the receiver-operating characteristic curve, had significantly higher mortality than those whose HDL cholesterol level was ≥15 mg/dL.
  
  
  
  Extremely low HDL cholesterol levels could be a useful marker for poor prognosis, not necessarily related to cardiovascular diseases.
authors.affiliation: Division of Cardiovascular Medicine, Kanazawa University Graduate School of Medicine, Kanazawa, Japan. Electronic address: ht240z@sa3.so-net.ne.jp.
authors.forename: Hayato
authors.initials: H
authors.lastname: Tada
authors.affiliation: Division of Cardiovascular Medicine, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
authors.forename: Masa-Aki
authors.initials: MA
authors.lastname: Kawashiri
authors.affiliation: Division of Cardiovascular Medicine, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Konno
authors.affiliation: Department of Advanced Research in Community Medicine, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nohara
authors.affiliation: Department of Clinical Laboratory Science, Faculty of Health Sciences Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Inazu
authors.affiliation: Department of Advanced Research in Community Medicine, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Mabuchi
authors.affiliation: Division of Cardiovascular Medicine, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yamagishi
authors.affiliation: Division of Cardiovascular Medicine, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
authors.forename: Kenshi
authors.initials: K
authors.lastname: Hayashi
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002423:Cause of Death; D008076:Cholesterol, HDL / Q000097:blood*; D003324:Coronary Artery Disease / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000209:etiology / Q000401:mortality; D015995:Prevalence; D011379:Prognosis; D016016:Proportional Hazards Models; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D012189:Retrospective Studies
chemical_list: D008076:Cholesterol, HDL
keywords: Coronary artery disease; HDL cholesterol; Lipids