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

Aims: there is no community-based cohort study to examine the effect of very high level of highdensity 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. © 2016,japan atherosclerosis society. all rights reserved.