Published papers

Aim: To examine whether the inflammatory markers C-reactive protein (CRP) and fibrinogen are associated with biomarkers of atherosclerosis [carotid intima-media thickness (IMT) and coronary artery calcification (CAC)] in the general male population, including Asians. Methods: Population-based samples of 310 Japanese, 293 Japanese-American and 297 white men 40-49 years of age without clinical cardiovascular disease underwent measurement of IMT, CAC and the CRP and fibrinogen levels as well as other conventional risk factors using standardized methods. Statistical associations between the variables were evaluated using multiple linear or logistic regression models. Results: The Japanese group had significantly lower levels of inflammatory markers and subclinical atherosclerosis than the Japanese-American and white groups (P-values all <0.001). The mean level of CRP was 0.66 vs. 1.11 and 1.47 mg/L, while that of fibrinogen was 255.0 vs. 313.0 and 291.5 mg/dl, respectively. In addition, the mean carotid IMT was 0.61 vs. 0.73 and 0.68 mm, while the mean prevalence of CAC was 11.6% vs. 32.1% and 26.3%, respectively. Body mass index (BMI) showed significant positive associations with both the CRP and fibrinogen levels. Although CRP showed a significant positive association with IMT in the Japanese men, this association became non-significant following adjustment for traditional risk factors or BMI. In all three populations, CRP was not found to be significantly associated with the prevalence of CAC. Similarly, fibrinogen did not exhibit a significant association with either IMT or the prevalence of CAC. Conclusions: The associations between inflammatory markers and subclinical atherosclerosis may merely reflect the strong associations between BMI and the levels of inflammatory markers and incidence of subclinical atherosclerosis in both Eastern and Western populations.

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.

Background: Abdominal fat distribution varies across groups with different races or environments. Whether environmental factors, apart from racial differences, affect abdominal fat distribution is unknown. Methods: We compared the abdominal fat distribution of four groups; different races with similar environments (Caucasians vs. Japanese Americans), different environments with an identical race (Japanese Americans vs. Japanese), and similar races with similar environments (Japanese vs. Koreans). A population-based sample of 1212 men aged 40-49 were analyzed: 307 Caucasians and 300 Japanese Americans in the United States, 310 Japanese in Japan, and 295 Koreans in Korea. We compared the proportion of visceral adipose tissue area to total abdominal adipose tissue area (VAT%) and other factors that can affect abdominal fat distribution (smoking, alcohol use, physical activity levels, and metabolic factors). Results: VAT% was significantly higher in Japanese and Koreans than in Japanese Americans and Caucasians (50.0, 48.5, 43.2, 41.0%, respectively, P < 0.001). Even after adjustment for possible confounders, the significant VAT% difference remained in comparing groups with identical race but different environments (i.e., Japanese vs. Japanese Americans). In contrast, comparing groups with different races but similar environments (i.e., Caucasians vs. Japanese Americans), VAT% was not significantly different. Comparing groups with similar races and similar environments (i.e., Japanese vs. Koreans), VAT% did not significantly differ. Conclusions: Environmental differences, apart from racial differences, affect the difference in abdominal fat distribution across different groups in middle-aged men.

Objective: There is little evidence to support an increased risk of blood pressure (BP) elevation among elderly individuals receiving antihypertensive drug treatment. Methods: To clarify the impact on BP level and residual cardiovascular risk in treated elderly individuals, we analysed individual participant data of 26 133 residents aged 60-89 years from seven Japanese general populations and cross-classified participants by age category, 60-74 (young-old) versus 75-89 years (old-old), and by usage of antihypertensive medication at baseline survey (1980-1995). Results: During a median follow-up period of 12.7 years, 2451 cardiovascular deaths were observed. Multivariable-Adjusted hazard ratios of cardiovascular mortality in treated participants compared with untreated participants were 1.30 [95% confidence intervals, 1.16-1.46) and 1.35 (95% confidence interval, 1.16-1.56) in young-old and old-old participants, respectively. Irrespective of antihypertensive medication, the risk increase of total cardiovascular and stroke mortality with elevation of BP was significant among young-old (P ≤ 0.0013), but not significant among old-old participants (P ≥ 0.061). Conclusion: Although impact on BP was more evident among young-old than old-old individuals, clinicians who prescribe antihypertensive medication to elderly patients should consider that such patients require further monitoring.

Background: The effect of very high or extremely high levels of high-density lipoprotein cholesterol (HDL-C) on cardiovascular disease (CVD) is not well described. Although a few recent studies have reported the adverse effects of extremely high levels of HDL-C on CVD events, these did not show a statistically significant association between extremely high levels of HDL-C and cause-specific CVD mortality. In addition, Asian populations have not been studied. Objective: We examine the impact of extremely high levels of HDL-C on cause-specific CVD mortality using pooled data of Japanese cohort studies. Methods: We performed a large-scale pooled analysis of 9 Japanese cohorts including 43,407 participants aged 40-89 years, dividing the participants into 5 groups by HDL-C levels, including extremely high levels of HDL-C ≥2.33 mmol/L (≥90 mg/dL). We estimated the adjusted hazard ratio of each HDL-C category for all-cause death and cause-specific deaths compared with HDL-C 1.04-1.55 mmol/L (40-59 mg/dL) using a cohort-stratified Cox proportional hazards model. Results: During a 12.1-year follow-up, 4995 all-cause deaths and 1280 deaths due to overall CVD were identified. Extremely high levels of HDL-C were significantly associated with increased risk of atherosclerotic CVD mortality (hazard ratio = 2.37, 95% confidence interval: 1.37-4.09 for total) and increased risk for coronary heart disease and ischemic stroke. In addition, the risk for extremely high HDL-C was more evident among current drinkers. Conclusion: We showed extremely high levels of HDL-C had an adverse effect on atherosclerotic CVD mortality in a pooled analysis of Japanese cohorts.

BACKGROUND: The structure and risk factors for cardiovascular diseases (CVD) in Japan may change because lifestyle, particularly nutrition, socioeconomic status, and medical care, which affect CVD, may markedly change over time. Therefore, a new prospective cohort study on a representative general Japanese population based on national surveys is required.METHODS: In November 2010, the baseline survey of the National Integrated Project for Prospective Observation of Non-communicable Disease and its Trends in the Aged 2010 (NIPPON DATA2010) was performed with the National Health and Nutrition Survey of Japan (NHNS2010) in 300 randomly selected districts throughout Japan. The survey included a questionnaire, electrocardiogram, urinalysis, and blood biomarkers added to the NHNS2010 examinations. Physical measurements, blood biomarkers, and dietary data were also obtained in NHNS2010. Socioeconomic factors were obtained by merging with the Comprehensive Survey of Living Conditions 2010 (CSLC2010) dataset. Participants are followed annually for the incidence of diabetes mellitus, CVD events (acute coronary events, heart failure, atrial fibrillation, and stroke), and cause-specific mortality. The activities of daily living are followed every 5 years.RESULTS: A total of 2,898 individuals aged 20 years or older agreed to participate in the baseline survey of NIPPON DATA2010. The participation rate was 74.6%. Of these, data from NHNS2010 was merged for 2,891 participants (1,236 men and 1,655 women). The data of 2,807 participants were also merged with CSLC2010 data.CONCLUSIONS: We established NIPPON DATA2010 as a cohort study on a representative general Japanese population that covers all of Japan.

Background: Advancing school-based education is a promising means to spread knowledge pertaining to stroke. The aim of the current study was to clarify whether stroke lessons provided by schoolteachers could deliver stroke knowledge to children (aged 9-11 years) and their parents, at a similar level to when taught by medical staff. Methods: Schoolteachers conducted lessons on stroke for school children using the educational materials we prepared (i.e., the teacher group; 1051 children and 719 parents). This was compared with our previous data from Akashi city and Tochigi prefecture, in which the stroke lessons were conducted by medical staff (i.e., the medical group; 1031 children and 756 parents). Three campaigns were conducted between September 2014 and May 2016. Each child was given education materials to take home to discuss stroke with their parents. The children and their parents answered questionnaires on stroke knowledge, at baseline, immediately after the lesson, and at 3 months after the lesson. Results: Compared with the time point before the lesson, both children and parents instructed by the teacher group showed significant increases in the scores about stroke symptoms and risk factors, immediately and at 3 months after the lesson (P < .001). The combined analysis for the group instructed by medical personnel showed no significant differences in the stroke knowledge scores between the 2 groups at 3 months. Conclusions: Teacher-led lessons, using our educational material, adequately delivered knowledge of stroke to children and parents, in a manner that was similar to when medical staff delivered this information.

BACKGROUND: Although socioeconomic status (SES) may affect food and nutrient intakes, few studies have reported on sodium (Na) and potassium (K) intakes among individuals with various SESs in Japan. We investigated associations of SES with Na and K intake levels using urinary specimens in a representative Japanese population.METHODS: This was a cross-sectional study of 2,560 men and women (the NIPPON DATA2010 cohort) who participated in the National Health and Nutrition Survey Japan in 2010. Casual urine was used to calculate estimated excretion in 24-hour urinary Na (E24hr-Na) and K (E24hr-K). The urinary sodium-to-potassium (Na/K) ratio was calculated from casual urinary electrolyte values. An analysis of covariance was performed to investigate associations of aspects of SES, including equivalent household expenditure (EHE), educational attainment, and job category, with E24hr-Na, E24hr-K, and the Na/K ratio for men and women separately. A stratified analysis was performed on educational attainment and the job category for younger (<65 years) and older (≥65 years) participants.RESULTS: In men and women, average E24hr-Na was 176.2 mmol/day and 172.3, average E24hr-K was 42.5 and 41.3, and the average Na/K ratio was 3.61 and 3.68, respectively. Lower EHE was associated with a higher Na/K ratio in women and lower E24hr-K in men and women. A shorter education was associated with a higher Na/K ratio in women and younger men, and lower E24hr-K in older men and women.CONCLUSION: Lower EHE and a shorter education were associated with a lower K intake and higher Na/K ratio estimated from casual urine specimens in Japanese men and women.

BACKGROUND: The relationship between socioeconomic status (SES) and knowledge of cardiovascular risk factors remains unknown in a general Japanese population.METHODS: Of 8,815 participants from 300 randomly selected areas throughout Japan, 2,467 participants who were free of cardiovascular disease and who provided information on SES in the National Health and Nutrition Survey of Japan 2010 were enrolled in this cross-sectional analysis. SES was classified according to the employment status, length of education, marital and living statuses, and equivalent household expenditure (EHE). Outcomes were ignorance of each cardiovascular risk factor (hypertension, diabetes, hypercholesterolemia, low high-density lipoprotein [HDL] cholesterol, arrhythmia, and smoking) and insufficient knowledge (number of correct answers <4 out of 6).RESULTS: A short education and low EHE were significantly associated with a greater ignorance of most cardiovascular risk factors. A short education (<10 years) was also associated with insufficient knowledge of overall cardiovascular risk factors: age- and sex-adjusted odds ratios (OR) were 1.92 (95% confidence interval [CI], 1.51-2.45) relative to participants with ≥13 years of education. Low EHE was also associated with insufficient knowledge (age- and sex-adjusted OR 1.24; 95% CI, 1.01-1.51 for the lowest quintile vs the upper 4 quintiles). These relationships remained significant, even after further adjustments for regular exercise, smoking, weekly alcohol consumption, body mass index, hypertension, diabetes mellitus, hypercholesterolemia, and low HDL cholesterol.CONCLUSION: Participants with a short education and low EHE were more likely to have less knowledge of cardiovascular risk factors.

BACKGROUND: Most studies on socioeconomic inequalities in oral health have not considered the effects of behavioral and biological factors and age differences. Furthermore, the nationwide status of inequalities remains unclear in Japan.METHODS: We analyzed data from 2,089 residents aged ≥40 years throughout Japan. The lowest quartile of the number of remaining teeth for each 10-year age category was defined as poor oral health. Behavioral and biological factors included smoking status, obesity, diabetes mellitus, high-sensitivity C-reactive protein, and the use of dental devices. Multiple logistic regression analyses were conducted to examine the associations of educational attainment and equivalent household expenditure (EHE) with oral health, and stratified analyses by age category were also conducted (40-64 years and ≥65 years).RESULTS: Lower education and lower EHE were significantly associated with an increased risk of poor oral health after adjusting for age, sex, employment status, marital and living statuses, and EHE/education; the odds ratio for junior high school education compared with ≥college education was 1.84 (95% confidence interval [CI], 1.36-2.49), and the odds ratio of the lowest compared with the highest EHE quartile was 1.91 (95% CI, 1.43-2.56). Further adjustments for behavioral and biological factors attenuated but did not eliminate these associations. EHE was significantly associated with oral health among elderly adults only, with a significant interaction by age category.CONCLUSIONS: Those with a lower education and those with lower EHE had a significantly higher risk of poor oral health, even after adjustments for behavioral and biological factors.

BACKGROUND: A lower socioeconomic status (SES) may be related to the intake of unhealthy food; however, this relationship has not been examined in detail. This study was undertaken to examine relationships among food group intakes and SES in a representative Japanese population.METHODS: This was a cross-sectional study using the baseline data of NIPPON DATA2010, which is a prospective cohort study of the National Health and Nutrition Survey in Japan. A total of 2,898 participants were included in the baseline survey in 2010. The effects of age (<65 years and ≥65 years), equivalent household expenditure (EHE), and education attainment on food group intakes (gram per 1,000 kcal) were analyzed using a two-way analysis of variance.RESULTS: When EHE was lower, cereal intake was higher in men and women. Among men, fish, milk, and alcohol intakes were reduced with lower EHE. Among women, vegetable intake was reduced with lower EHE. In men and women, cereal intake was higher with lower education attainment. In contrast, meat intake was reduced with lower education attainment.CONCLUSIONS: Lower SES was associated with a higher cereal intake and lower vegetable, fish, meat, and milk intakes in a representative Japanese population. Socioeconomic discrepancies need to be considered in order to promote healthier dietary habits.

BACKGROUND: Socioeconomic status (SES) imbalances in developed and developing countries may result in individuals being overweight and obese. However, few studies have investigated this issue in Japan. We herein examined the relationship between SES and being underweight, overweight or obese according to sex and age groups (20-64 or ≥65 years) in Japan.METHODS: In 2010, we established a cohort of participants in the National Health and Nutrition Survey of Japan. We divided 2,491 participants (1,081 men and 1,410 women) according to the WHO definitions of underweight, overweight or obesity and performed multinomial logistic analyses using BMI <18.5 kg/m2 (underweight), BMI 25.0-29.9 kg/m2 (overweight), and BMI ≥30.0 kg/m2 (obese) versus BMI 18.5-24.9 kg/m2 (normal) as the outcome, with SES groups as the main explanatory variables.RESULTS: In adult men, a lower education level relative to a higher education level was inversely associated with obesity after adjustments for other SESs (odds ratio [OR] 0.41; 95% confidence interval [CI], 0.18-0.96). However, in adult women, lower education level was positively associated with being overweight and obese (OR 1.67; 95% CI, 1.07-2.49 for overweight and OR 2.66; 95% CI, 1.01-7.01 for obese). In adult women, a lower household income was positively associated with being overweight and obese (obese: OR 4.84; 95% CI, 1.36-17.18 for those with a household income <2 million JPY relative to those with ≥6 million JPY).CONCLUSIONS: In adult women, a lower education level and lower household income were positively associated with being overweight or obese. In contrast, in adult men, a lower education level was inversely associated with obesity. Gender and age differences in SESs affect the prevalence of being overweight or obese.

BACKGROUND: This study examined the relationships among household income, other SES indicators, and macronutrient intake in a cross-sectional study of a representative Japanese population.METHODS: In 2010, we established a cohort of participants in the National Health and Nutrition Survey (NHNS) from 300 randomly selected areas throughout Japan. A total of 2,637 participants (1,145 men and 1,492 women) were included in the study. Data from NHNS2010 and the Comprehensive Survey of Living Conditions 2010 (CSCL2010) were merged, and relationships among macronutrient intake and SES were evaluated. Additionally, socioeconomic factors associated with a risk of a higher carbohydrate/lower fat intake beyond dietary recommendations were evaluated.RESULTS: Household income was positively associated with fat intake (P = 0.001 for men and <0.001 for women) and inversely associated with carbohydrate intake (P = 0.003 for men and <0.001 for women) after adjustments for age and other SES variables. Similar relationships were observed between equivalent household expenditure (EHE) and macronutrient intake; however, these relationships were weaker than those of household income. Older age was the factor most strongly associated with a high carbohydrate/low fat intake, followed by household income, EHE, education levels, and occupation type.CONCLUSIONS: Older age was the factor most strongly associated with a high carbohydrate/low fat intake, and some aspects of SES, such as household income, EHE, education levels, and occupation type, were independently associated with an imbalanced macronutrient intake. SES may affect the health status of individuals through the intake of macronutrients.

BACKGROUND: This study investigated relationships among socioeconomic factors and participation in health examinations for Japanese National Health Insurance (NHI) using a representative Japanese population.METHODS: We used the linkage database of NIPPON DATA2010 and Comprehensive Survey of Living Conditions 2010. Participants with NHI aged 40-74 years were included in the analysis. Prevalence ratios (PRs) for participation in health examinations in the past year were set as an outcome. Participant characteristics, including sex, age, socioeconomic factors (educational attainment, employment, equivalent household expenditure [EHE], house ownership, and marital status), laboratory measures, and lifestyle were included in an age-stratified modified Poisson regression analysis to examine relationships.RESULTS: The number of study participants was 812, and 564 (69.5%) participated in health examinations in the past year. Among those aged 40-64 years, there was no significant PR for socioeconomic factors. Among those aged 65-74 years, high (≥13 years) educational attainment (adjusted PR, 1.22; 95% confidence interval [CI], 1.05-1.41) and house ownership (PR 1.40; 95% CI, 1.11-1.77) were positively associated with participation, while high (4th quartile) EHE (PR 0.84; 95% CI, 0.73-0.97) was negatively associated.CONCLUSION: These results suggest that high educational attainment, house ownership, and low EHE were positive factors for participation in health examinations among those aged 65-74 years.

BACKGROUND: The relationships among socioeconomic status and lifestyle improvements have not yet been examined in a representative Japanese population.METHODS: We analyzed data from 2,647 participants (1,087 men and 1,560 women) who participated in NIPPON DATA2010. This survey inquired about lifestyle improvements and socioeconomic status. Education was categorized as low (≤9 years), middle (10-12 years), and high (≥13 years). Marital status was categorized as married, divorced, widowed, and never married/other. A multivariable logistic regression model was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of lifestyle improvements with the intention of preventing cardiovascular diseases for educational attainment and marital status, with adjustments for age and awareness of cardiovascular disease risk factors.RESULTS: Overall, 1,507 (56.9%) participants practiced prevention and improvements in hypertension, diabetes, elevated cholesterol, and metabolic syndrome, and the OR of lifestyle improvements was significantly higher with a high education than with a low education in men (OR 2.86; 95% CI, 1.96-4.17) and women (OR 2.36; 95% CI, 1.67-3.33). The number of participants who practiced prevention and improvements in hypertension, diabetes, elevated cholesterol, and metabolic syndrome was significantly lower in divorced than in married men (OR 0.46; 95% CI, 0.22-0.95) and women (OR 0.53; 95% CI, 0.33-0.86).CONCLUSIONS: Specific differences caused by educational attainment and marital status may exist in lifestyle improvements.

Excessive salt intake is an established risk factor for hypertension. We conducted a cross-sectional study to examine the association between salty taste recognition and estimated salt intake and masked hypertension in a healthy Japanese normotensive population. The participants were 892 apparently healthy community residents (246 men and 646 women) aged between 40 and 74 years with blood pressure below 140/90 mm Hg. Salty taste recognition was assessed using a salt-impregnated taste strip. Daily salt intake was calculated as estimated 24 h urinary sodium excretion using spot urine tests. Each participant performed home blood pressure measurements for a minimum of 5 days per week. The participants were classified into three groups according to their salty taste recognition threshold evaluated by the salt concentrations of the taste strips (0.6%, 0.8%, and ≥ 1.0%). In women, the multivariate odds ratio (95% confidence interval) for masked hypertension (≥ 135/85 mm Hg) was 2.98 (1.16–7.64) in the ≥ 1.0% group compared with that in the 0.6% group. In men, the proportion of masked hypertension in the ≥ 1.0% group did not differ from that in the 0.6% group, and no correlation was identified between estimated daily salt intake and the salty taste recognition threshold. In conclusion, impairment of salty taste recognition was associated with masked hypertension in women even with normal blood pressure in the clinical setting.

Background: The relative and absolute risks of stroke and heart failure attributable to atrial fibrillation (AF) have not been sufficiently examined. Methods: A prospective study of 23,731 community-dwelling Japanese individuals was conducted. Participantswere divided into two groups based on the presence or absence of prevalent AF (n = 338 and n = 23,393, respectively). Excess events (EE) due to AF and relative risks (RRs) determined using the non-AF group as the reference for incident stroke and heart failurewere estimated using Poisson regression stratified by age groups (middle-aged: 40-69 years old; elderly: 70 years of age or older) after adjustment for sex and age. Results: There were 611 cases of stroke and 98 cases of heart failure during the observation period (131,088 person-years). AF contributed to a higher risk of stroke both in middle-aged individuals (EE 10.4 per 1000 person-years;RR4.88;95%confidenceinterval [CI],2.88-8.29) andelderlyindividuals (EE18.3per1000 personyears; RR 3.05; 95% CI, 2.05-4.54). AFalso contributed to a higher risk of heart failure in middle-aged individuals (EE 3.7 per 1000 person-years; RR 8.18; 95% CI, 2.41-27.8) and elderly individuals (EE 15.4 per 1000 personyears; RR 7.82; 95% CI, 4.11-14.9). Results obtained from multivariate-adjusted analysis were similar (stroke: EE 8.9 per 1000 person-years; RR 4.40; 95% CI, 2.57-7.55 inmiddle-aged and EE 17.4 per 1000 person-years; RR 2.97; 95% CI, 1.99-4.43 in elderly individuals; heart failure: EE 3.1 per 1000 person-years; RR 7.22; 95% CI, 2.06-25.3 in middle-aged and EE 14.1 per 1000 person-years; RR 7.41; 95% CI, 3.86-14.2 in elderly individuals). Conclusions: AF increased the risk of stroke by the same magnitude as that reported previously in Western countries. AF increased the RR of heart failure more than that in Western populations.

We investigated the relationship between smoking and the risk of nonnormal (≤0.99) ankle-brachial index (ABI) at rest and after ankle plantar flexion exercise in healthy male community dwellers. A cross-sectional study was performed including 228 Japanese men aged 40 to 64 years without a history of cardiovascular diseases. Participants were classified as never, ex-, and current smokers. We estimated the multivariate-adjusted odds ratios (ORs) for nonnormal ABI of ex- and current smokers in relation to never smokers after adjusting for age and other confounding factors. At rest, the prevalence of nonnormal ABI was not significantly different by smoking status. After exercise, the prevalence of nonnormal ABI increased from 1.8% to 11.5% in ex-smokers and from 3.8% to 17.0% in current smokers, while the prevalence did not significantly change in never smokers. The multivariate-adjusted OR for nonnormal ABI after ankle plantar flexion exercise, in relation to never smokers, was 3.85 (95% confidence interval [CI]: 0.79-18.9) for ex-smokers and 6.97 (95% CI: 1.32-36.7) for current smokers. Our results suggest that ABI after ankle plantar flexion exercise is useful for early detection of subclinical peripheral artery ischemia in male smokers without typical symptoms.