藤井 亮輔

Although previous studies reported that BP PRS is associated with CVD, it is less explored whether BP PRS and BP are jointly associated with CVD, especially among non-European populations. Therefore, we examined joint associations of BP control and BP polygenic risk score (PRS) with CVD mortality in a Japanese population. Data were obtained from the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study, the multi-centered cohort study with 14 study areas throughout Japan. Of which, we analyzed ~35,000 Japanese individuals (Mean age: 55 years old, Men: 44%) with measured BP data (11,242 and 23,904 participants in subgroup #1 and #2). We developed PRS for systolic blood pressure (SBP) and diastolic blood pressure (DBP) in each subgroup. Participants were followed up from the baseline survey (2005-2014) to the end of 2020. Not elevated BP was defined as SBP ≤ 140 mmHg or DBP ≤ 90 mmHg regardless of antihypertensive medications. During the follow-up period, a total of 381 CVD deaths were observed. Compared with not elevated BP, HRs (95% CI) of CVD mortality were 1.98 (1.37-2.88) for elevated SBP and 2.41 (1.66-3.49) for elevated DBP. Compared to not elevated BP in the lowest PRS tertile, HRs (95% CI) of CVD mortality in the highest PRS tertile were 2.28 (1.17-4.43) for SBP and 3.08 (1.61-5.91) for DBP even though BP was not elevated. These associations in the subgroup #1 were replicated in the subgroup #2. Our findings highlighted the importance of BP PRS to detect a hidden CVD risk strata in addition to laboratory BP measurements.

BACKGROUND: Although utility of composite trait-specific polygenic risk score (multi-trait PRS) has been examined among European ancestries, few studies investigated among East Asians and incorporated modifiable risk factors. We examined the associations of multi-trait PRS for cardiometabolic factors with cardiovascular disease mortality by integrating nongenetic determinants. METHODS: A total of 14 086 Japanese participants (mean age, 55±9; 55.8% women) of the J-MICC (Japan Multi-Institutional Collaborative Cohort) study were analyzed in this study. We calculated 6 PRSs for cardiometabolic traits (systolic blood pressure, body mass index, triglycerides, low-density lipoprotein cholesterol, estimated glomerular filtration rate, and hemoglobin A1c). Based on these PRSs, we developed multi-trait PRS and considered as a primary exposure. Three nongenetic factors (smoking, alcohol drinking, and educational attainment) from the self-reported questionnaire were also examined. RESULTS: During a median 12.1-year follow-up period, a total of 472 all-cause and 79 cardiovascular disease mortality cases were documented. Compared with 0% to 90% of multi-trait PRSs, an adjusted hazard ratio (HR) among the top 10% of multi-trait PRSs was 1.32 (95% CI, 1.00-1.73) for all-cause death and 2.63 (95% CI, 1.48-4.67) for cardiovascular disease death. Incorporation of educational attainment with multi-trait PRSs showed null associations in those who went beyond high school (HR, 2.07 [95% CI, 0.44-9.66]) even in the top 10% of multi-trait PRS. CONCLUSIONS: Our analysis combining both genetic and nongenetic determinants highlighted that lifestyle factors and educational attainment can slightly reduce an individual's composite genetic risk for cardiovascular disease death.