Published papers

OBJECTIVES: To evaluate the impact of dietary sodium and potassium (Na-K) ratio on mortality from total and subtypes of stroke, cardiovascular disease (CVD) and all causes, using 24-year follow-up data of a representative sample of the Japanese population.SETTING: Prospective cohort study.PARTICIPANTS: In the 1980 National Cardiovascular Survey, participants were followed for 24 years (NIPPON DATA80, National Integrated Project for Prospective Observation of Non-communicable Disease And its Trends in the Aged). Men and women aged 30-79 years without hypertensive treatment, history of stroke or acute myocardial infarction (n=8283) were divided into quintiles according to dietary Na-K ratio assessed by a 3-day weighing dietary record at baseline. Age-adjusted and multivariable-adjusted HRs were calculated using the Mantel-Haenszel method and Cox proportional hazards model.PRIMARY OUTCOME MEASURES: Mortality from total and subtypes of stroke, CVD and all causes.RESULTS: A total of 1938 deaths from all causes were observed over 176 926 person-years. Na-K ratio was significantly and non-linearly related to mortality from all stroke (p=0.002), CVD (p=0.005) and total mortality (p=0.001). For stroke subtypes, mortality from haemorrhagic stroke was positively related to Na-K ratio (p=0.024). Similar relationships were observed for men and women. The observed relationships remained significant after adjustment for other risk factors. Quadratic non-linear multivariable-adjusted HRs (95% CI) in the highest quintile versus the lowest quintile of Na-K ratio were 1.42 (1.07 to 1.90) for ischaemic stroke, 1.57 (1.05 to 2.34) for haemorrhagic stroke, 1.43 (1.17 to 1.76) for all stroke, 1.39 (1.20 to 1.61) for CVD and 1.16 (1.06 to 1.27) for all-cause mortality.CONCLUSIONS: Dietary Na-K ratio assessed by a 3-day weighing dietary record was a significant risk factor for mortality from haemorrhagic stroke, all stroke, CVD and all causes among a Japanese population.

BACKGROUND: C-reactive protein (CRP) and many fatty acids (FAs) have been linked to cardiovascular disease. Associations of serum CRP with FAs in different populations have not been established.METHODS: Participants were 926 men aged 40-49 (2002-2006) from a population-based sample; 310 Whites from Pennsylvania, U.S., 313 Japanese from Shiga, Japan, and 303 Japanese Americans from Hawaii, U.S. Serum CRP (mg/L) was measured using immunosorbent assay while serum FAs (%) were measured using capillary-gas-liquid chromatography.RESULTS: Whites had CRP (mg/L) levels higher than Japanese with Japanese Americans in-between (age-adjusted geometric mean "GM" 0.96, 0.38, 0.66, respectively). Whites had also higher levels of total n-6 FAs (%) and trans fatty acids (TFAs) but lower levels of marine-derived n-3 FAs compared to Japanese (41.78 vs. 35.05, 1.04 vs. 0.58, and 3.85 vs. 9.29, respectively). Japanese Americans had FAs levels in-between the other two populations. Whites had significant inverse trends between CRP and tertiles of total n-6 FAs (GM 1.20, 0.91 and 0.80; p=0.002) and marine-derived n-3 FAs (GM 1.22, 1.00 and 0.72; pCONCLUSIONS: With the exception of consistent inverse association of CRP with total n-6 FAs, there are considerable variations across the three populations in the associations of CRP with different FAs.

Background: C-reactive protein (CRP) and many fatty acids (FAs) have been linked to cardiovascular disease. Associations of serum CRP with FAs in different populations have not been established. Methods: Participants were 926 men aged 40-49 (2002-2006) from a population-based sample; 310 Whites from Pennsylvania, U.S., 313 Japanese from Shiga, Japan, and 303 Japanese Americans from Hawaii, U.S. Serum CRP (mg/L) was measured using immunosorbent assay while serum FAs (%) were measured using capillary-gasliquid chromatography. Results: Whites had CRP (mg/L) levels higher than Japanese with Japanese Americans in-between (age-adjusted geometric mean “GM” 0.96, 0.38, 0.66, respectively). Whites had also higher levels of total n-6 FAs (%) and trans fatty acids (TFAs) but lower levels of marine-derived n-3 FAs compared to Japanese (41.78 vs. 35.05, 1.04 vs. 0.58, & 3.85 vs. 9.29, respectively). Japanese Americans had FAs levels in-between the other two populations. Whites had significant inverse trends between CRP and tertiles of total n-6 FAs (GM 1.20, 0.91 & 0.80; p=0.002) and marine-derived n-3 FAs (GM 1.22, 1.00 & 0.72; p

Aims: Lectin-like oxidized low-density lipoprotein (LDL) receptor-1 ligands containing apolipoprotein B (LAB) and lectin-like oxidized LDL receptor-1 (LOX-1) are known as LOX-1-related modified LDL indicators. These indicators play an important role in the early phase atherosclerosis, but the relationship between these indicators and subclinical atherosclerosis, as represented by the cardioankle vascular index (CAVI), has not been assessed. We herein investigated the association of LOX-1- related modified LDL indicators and the CAVI in healthy, Japanese urban community inhabitants who were considered to be at low risk for cardiovascular disease (CVD). Methods: The participants were 515 healthy Japanese (310 men and 205 women) without a history of CVD, cancer or the use of medication for hypertension, diabetes or dyslipidaemia. To estimate the association between LOX-1-related modified LDL indicators (LAB, soluble form of LOX-1 (sLOX- 1)) and the CAVI, we performed multivariable linear regression analyses with possible confounders such as the serum LDL cholesterol level. Results: The plasma LAB showed a positive association with the CAVI in men (standardized coefficient: 0.11, p= 0.04). This relationship was not observed in women. On the other hand, no clear association was observed between the CAVI and the plasma sLOX-1 level in either sex. Conclusions: The plasma LAB levels may represent a useful marker for detecting potential atherosclerosis in healthy individuals considered to be at low risk for atherosclerosis and CVD. Further studies are needed to confirm the present findings.

Background/Objectives: Serum polyunsaturated fatty acid (PUFA) composition reflects dietary intake and is related to risks for cardiovascular diseases. We hypothesized that serum n-3 PUFA composition, especially including long-chain n-3 PUFA such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is associated with inflammatory status, which is related to increased risk for cardiovascular diseases. Subjects/Methods: We investigated the relationship between serum PUFA composition and high-sensitivity C-reactive protein (hs-CRP) levels in a cross-sectional study among 1,102 healthy men and women aged 40–74 years who reside in Kobe City. Multiple linear regression models that predict hs-CRP level were prepared to confirm the contribution of serum total n-3 PUFA, long-chain n-3 PUFA, EPA and DHA compositions after adjusting for other PUFAs and atherosclerotic risk factors. Results: The serum n-3 PUFA, particularly long-chain n-3 PUFA, compositions were inversely associated with the hs-CRP levels. The standardized regression coefficient was −0.089 (p < 0.01) for total n-3 PUFA, −0.091 (p < 0.01) for long-chain n-3 PUFA, −0.071 (p = 0.03) for EPA, and −0.068 (p = 0.04) for DHA. The n-6 PUFA compositions were also inversely associated with the hs-CRP levels (−0.169 [p < 0.01] for total n-6 PUFA and −0.159 [p < 0.01] for linoleic acid). Conclusions: The serum n-3 PUFA compositions were inversely related with the hs-CRP levels, similar associations were also observed in n-6 PUFA compositions. Our results suggest that dietary PUFA intake was inversely associated with attenuated inflammation in healthy Japanese population.