title: The Relationship between Very High Levels of Serum High-Density Lipoprotein Cholesterol and Cause-Specific Mortality in a 20-Year Follow-Up Study of Japanese General Population.
abstract: OBJECTIVE
  There is no community-based cohort study to examine the effect of very high level of high-density lipoprotein cholesterol (HDL-C) on coronary heart disease (CHD) and other cause-specific mortality. Therefore, we investigated the relationship between HDL-C including very high level and cause-specific mortality in a 20-year cohort study of the representative sample of Japanese.
  
  
  METHODS
  We followed 7,019 individuals from the Japanese general population (2,946 men and 4,073 women). We defined HDL-C levels as follow: low (HDL-C ＜1.04 mmol/L), reference (1.04-1.55 mmol/L), high (1.56-2.06 mmol/L), very high (≥2.07 mmol/L). The multivariate adjusted hazard ratio (HR) for all-cause or cause-specific mortality was calculated using a Cox proportional hazards model adjusted for other traditional risk factors.
  
  
  RESULTS
  During follow-up, we observed 1,598 deaths. No significant association was observed between HDL-C and all-cause mortality. Serum HDL-C also showed no association with stroke. In contrast, the risk for CHD among high HDL-C was lower than reference, HRs were 0.51 [95% confidence interval (CI): 0.21-1.23] in men, 0.33 (95% CI: 0.11-0.95) in women, and 0.41 (95% CI: 0.21-0.81) when men and women were combined. However, very high HDL-C did not show significant association with CHD and other cause-specific mortality.
  
  
  CONCLUSIONS
  HDL-C was not associated with all-cause and stroke mortality. In contrast, high serum HDL-C levels, at least up to 2.06 mmol/L, were protective against CHD, although further high levels were not. However, sample size of cause-specific death in very high HDL-C group was not enough even in this 20-year follow-up of 7,019 Japanese; larger cohort studies should be warranted.
authors.affiliation: Department of Preventive Medicine and Public Health, Keio University School of Medicine.
authors.forename: Aya
authors.initials: A
authors.lastname: Hirata
authors.forename: Tomonori
authors.initials: T
authors.lastname: Okamura
authors.forename: Daisuke
authors.initials: D
authors.lastname: Sugiyama
authors.forename: Kazuyo
authors.initials: K
authors.lastname: Kuwabara
authors.forename: Aya
authors.initials: A
authors.lastname: Kadota
authors.forename: Akira
authors.initials: A
authors.lastname: Fujiyoshi
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Miura
authors.forename: Nagako
authors.initials: N
authors.lastname: Okuda
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ohkubo
authors.forename: Akira
authors.initials: A
authors.lastname: Okayama
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Ueshima
mesh_terms: D000328:Adult; D044466:Asian People / Q000706:statistics & numerical data*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends*; D012307:Risk Factors
chemical_list: D008075:Lipoproteins, HDL