The asymmetric dimethylarginine level is associated with the predicted stroke risk in Japanese women

Intima-Media Thickness in the Carotid Bifurcation is Related to Silent Brain Infarction: A Cross-Sectional Study

AIMS

Carotid intima-media thickness (IMT) measurement is used to assess subclinical atherosclerosis. We aimed to examine the association between the maximum IMT by location and the occurrence of silent brain infarction (SBI).

METHODS

Overall, 280 Japanese individuals (92 females, 52.6±5 years old) underwent a medical check-up at our hospital in Tokyo in 2015. Carotid IMT was measured at each site on ultrasound images (common carotid artery [CCA], internal carotid artery, or bifurcation). The risk factors for arterial dysfunction were evaluated. SBI was assessed using magnetic resonance imaging (MRI). The cross-sectional relationship between carotid maximum IMT and SBI was evaluated.

RESULTS

Of the 280 individuals, 18 (6.4%) were diagnosed with SBI on MRI. The mean age of the SBI(-) and SBI(+) groups was 51.9±10.6 and 63.6±18.6 years, respectively. The correlation coefficients between the carotid maximum IMT at each location were very weak (correlation coefficient range: 0.180-0.253). The percentage of participants with SBI increased significantly with increasing maximum CCA and bIMT values. After adjusting for confounders, SBI was found to be significantly associated with the maximum bIMT (per 0.1-mm increase) (adjusted odds ratio [aOR], 1.10; 95% confidence interval [CI]: 1.03-1.17). When bIMT was categorized according to three groups (＜1.0 mm, 1.0-＜2.0 mm, and ≥ 2.0 mm), a significant SBI risk was also observed with an increase by each category of bIMT (aOR: 3.96, 95% CI: 1.63-9.52, P=0.002).

CONCLUSION

The maximum bIMT was found to be the main determinant of SBI. A significant SBI risk was associated with an increase in each category of the maximum bIMT. Therefore, the maximum bIMT might be a useful predictor of future stroke in Japanese stroke-free medical check-up participants.

Elevated cardio-ankle vascular index may be related to future stroke risk in Japanese subjects

BACKGROUND

The cardio-ankle vascular index (CAVI) has been proposed as a useful parameter for arteriosclerotic diseases. However, whether it is associated with stroke risk in Japanese subjects remains unclear.

METHODS

In total, 280 Japanese subjects (92 females, 52.6 ± 5 years old) underwent a medical check-up. CAVI value and risk factors for arterial dysfunction were evaluated; the predicted 10-year stroke risk was measured by the Japan Public Health Center study.

RESULTS

Age, sex, body mass index, and systolic blood pressure were significant independent predictors of CAVI. CAVI values were significantly elevated in the high, compared with the medium-low and low predicted risk groups. A significant odds ratio (OR) for the high-risk group was noted in the highest quartile of CAVI values (OR, 14.67; 95% confidence interval [CI], 3.17-68.0), compared with the lowest quartile, after adjusting for potential confounders. A significant OR for very high predicted stroke risk was also found for each quartile increase (OR, 3.04; 95% CI, 1.87-4.94) and 1-standard deviation increase (OR, 2.24; 95% CI, 1.52-3.30) in CAVI value.

CONCLUSION

Elevated CAVI values were related to an elevated predicted stroke risk, suggesting that CAVI could be a suitable surrogate marker for finding subjects at an increased risk of first-ever stroke.

Risk Factors for Stroke among Young-Old and Old-Old Community-Dwelling Adults in Japan: The Ohasama Study

AIM

Few studies have addressed stroke risk factors in older populations, particularly among the old-old. We examined differences in traditional risk factors for stroke among the old-old compared with the young-old in community-dwelling Japanese adults.

METHODS

We followed 2,065 residents aged ≥ 60 years who had no history of stroke. Traditional risk factors for stroke were obtained from a self-administered questionnaire at baseline. We classified participants into two age categories, 60-74 years (n=1,502) and ≥ 75 years (n=563), and assessed whether traditional risk factors were differentially associated with stroke incidence according to age category. Hazard ratios were calculated by the Cox proportional hazards model, adjusting for confounding factors and competing risk of death.

RESULTS

During a median follow-up of 12.8 and 7.9 years, 163 and 111 participants aged 60-74 and ≥ 75 years, respectively, developed a first stroke. Hypertension was consistently associated with increased risk of stroke, regardless of age category. Diabetes mellitus was associated with increased risk of stroke in those aged 60-74 years (hazard ratio, 1.50; 95% confidence interval, 1.00-2.25), but not in those aged ≥ 75 years (hazard ratio, 0.65; 95% confidence interval, 0.33-1.29), with significant interaction by age (P=0.035). No traditional risk factor other than hypertension was associated with stroke among those aged ≥ 75 years.

CONCLUSION

Those with hypertension had significantly higher stroke risk among old people, while diabetes mellitus was differentially associated with stroke according to age category. Our findings indicate the importance of different prevention strategies for stroke incidence according to age category.