title: High-density lipoprotein subclasses and risk of stroke and its subtypes in Japanese population: the Circulatory Risk in Communities Study.
abstract: OBJECTIVE
  High-density lipoprotein (HDL) cholesterol is an established protective factor for ischemic stroke. However, the contribution of HDL subclasses to stroke risk and its subtypes is uncertain.
  
  
  METHODS
  A prospective nested case-control study of 40- to 85-year-old Japanese was undertaken using frozen serum samples collected from 5280 men and 7524 women. They participated in cardiovascular risk surveys from 1985 to 1999 (1 community) and 1989 to 1998 (2 communities) under Circulatory Risk in Communities Study. HDL cholesterol subclasses were classified by high-performance liquid chromatography into 3 subgroups: S-HDL (very small or small HDL), M-HDL (medium HDL), and L-HDL (large or very large HDL) cholesterol. One control subject per case was matched by sex, age, community, serum storage year, and fasting status.
  
  
  RESULTS
  In 2005, we identified 241 strokes (155 ischemic and 86 hemorrhagic). S-HDL and M-HDL cholesterol levels were inversely associated with total stroke risk, ischemic stroke, specifically lacunar infarction, and hemorrhagic stroke. After adjustment for cardiovascular risk factors, these associations remained statistically significant. Multivariable conditional odds ratios (95% confidence interval) for 1 SD (0.12 mmol/L) increment of S-HDL cholesterol levels were 0.34 (0.23-0.52) for total stroke, 0.38 (0.23-0.63) for ischemic stroke, 0.33 (0.18-0.61) for lacunar infarction, 0.30 (0.14-0.65) for hemorrhagic stroke, and 0.30 (0.12-0.77) for intraparenchymal hemorrhage. The respective multivariable odds ratios for 1SD (0.10 mmol/L) increment of M-HDL cholesterol levels were 0.56 (0.41-0.75), 0.63 (0.45-0.88), 0.59 (0.40-0.87), 0.41 (0.21-0.80), and 0.38 (0.16-0.90). No associations were found between L-HDL cholesterol levels and risk of total stroke and its subtypes.
  
  
  CONCLUSIONS
  Small- to medium-sized HDL, not large HDL, cholesterol levels were inversely associated with total stroke risk.
authors: Department of Public Health Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors: Choy-Lye
authors: CL
authors: Chei
authors: Kazumasa
authors: K
authors: Yamagishi
authors: Akihiko
authors: A
authors: Kitamura
authors: Masahiko
authors: M
authors: Kiyama
authors: Hironori
authors: H
authors: Imano
authors: Tetsuya
authors: T
authors: Ohira
authors: Renzhe
authors: R
authors: Cui
authors: Takeshi
authors: T
authors: Tanigawa
authors: Tomoko
authors: T
authors: Sankai
authors: Yoshinori
authors: Y
authors: Ishikawa
authors: Shinichi
authors: S
authors: Sato
authors: Shinichi
authors: S
authors: Hitsumoto
authors: Hiroyasu
authors: H
authors: Iso
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000208:ethnology*; D015415:Biomarkers / Q000097:blood; D001775:Blood Circulation / Q000502:physiology*; D002545:Brain Ischemia / Q000097:blood / Q000208:ethnology; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood* / Q000145:classification*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012111:Residence Characteristics; D012307:Risk Factors; D020521:Stroke / Q000097:blood* / Q000208:ethnology*
chemical_list: D015415:Biomarkers; D008075:Lipoproteins, HDL