Dyslipidemia is a major determinant of systemic atherosclerosis in the elderly: An autopsy study

Age and Gender-Specific Pattern of Cardiovascular Disease Risk Factors in Saudi Arabia: A Subgroup Analysis from the Heart Health Promotion Study

OBJECTIVE

To investigate gender and age-specific distribution patterns of cardiovascular disease risk factors in the Saudi population for tailored health policies.

METHODS

From the heart health promotion study, 3063 adult Saudis were included in this study. The study cohort was divided into five age groups (less than 40 years, 40-45 years, 46-50 years, 51-55 years and ≥56 years). The prevalence of metabolic, socioeconomic, and cardiac risk was compared between the groups. Anthropometric and biochemical data were gathered using the World Health Organization stepwise approach to chronic disease risk factors. The cardiovascular risk (CVR) was determined using the Framingham Coronary Heart Risk Score.

RESULTS

The prevalence of CVR risk increased with age in both genders. Both Saudi men and women exhibit similar propensities for sedentary lifestyles and unhealthy food habits. The prevalence of tobacco smoking was significantly higher and from an early age in males compared to females (28% and 2.7%, respectively, at age 18-29 years). There is no significant difference in either the prevalence of diabetes, hypertension, or metabolic syndrome between men and women before the age of 60 years. Old Saudi females (≥60 years) have a higher prevalence of diabetes (50% vs. 38.7%) and metabolic syndrome (55.9% versus 43.5%). Obesity was more prevalent in females aged 40-49 years onwards (56.2% vs. 34.9% males), with 62.9% of females aged ≥60 years being obese compared to 37.9% of males. Dyslipidaemia prevalence increased with the progression of age, significantly more in males than females. Framingham high-risk scores showed that 30% of males were at high risk of cardiovascular diseases at the age group of 50-59 years, while only 3.7% of the females were considered as such.

CONCLUSIONS

Both Saudi men and women exhibit similar propensities for sedentary lifestyles and unhealthy food habits, with a marked increase in cardiovascular and metabolic risk factors with age. Gender differences exist in risk factor prevalence, with obesity as the main risk factor in women, while smoking and dyslipidaemia were the main risk factors in men.

Change of carotid intima-media thickness is associated with age in elderly Japanese patients without a history of cardiovascular disease

AIM

The present study aimed to evaluate the relationship between the change of carotid intima-media thickness (CIMT) and clinical characteristics in Japanese patients without a history of cardiovascular disease.

METHODS

The study participants were 149 Japanese patients without a history of cardiovascular disease treated in our outpatient department. The in all participants CIMT was measured with ultrasonography at baseline and after a mean interval of 2.4 years. Study participants were divided into a middle-aged group (younger than 65 years: n = 59) and an elderly group (65 years or older: n = 90). The annual CIMT change (ΔCIMT) was calculated, and the associations between ΔCIMT and clinical characteristics, including age, were evaluated in both groups.

RESULTS

The ΔCIMT was significantly correlated with age in all participants (r = 0.222; P < 0.05) and in elderly participants (r = 0.234; P < 0.05), but was not correlated with other risk factors. The annual ΔCIMT was significantly higher in elderly participants (0.015 ± 0.096 mm) than in middle-aged participants (-0.018 ± 0.088 mm; P < 0.05). Multivariate linear regression analysis with ΔCIMT as a dependent variable and risk factors as independent variables showed that ΔCIMT was significantly associated with age in all participants (β = 0.002; P < 0.05) and in elderly participants (β = 0.004; P < 0.05), but not with other risk factors.

CONCLUSIONS

Annual CIMT change is associated with age, rather than with other clinical characteristics, including traditional cardiovascular risk factors, such as diabetes and hypertension, in elderly Japanese patients without a history of cardiovascular disease.

Dyslipidemia and the risk of incident hypertension in a population of community-dwelling Brazilian elderly: the Bambuí cohort study of aging

This study aimed to examine the prognostic value of lipid parameters for incident hypertension in elderly living in a community. The study included 306 (81% from total) persons aged > 60 years who were free of hypertension and of cardiovascular diseases at the baseline survey of the Bambuí Cohort Study of Aging. The cumulative incidence of hypertension over three years was 37.3%. The relative risk (RR) of incident hypertension decreased 0.92 for each unit of HDL-cholesterol (95%CI: 0.86-0.99) independent of several potential confounding factors. Individuals with HDL-cholesterol in the top tercile (> 55mg/dL) had a risk of hypertension halve that those in the bottom tercile (RR = 0.54; 95%CI: 0.33-0.90). Other lipid parameters had no significant effect on the outcome. High HDL-cholesterol showed an independent protective effect on subsequent development of hypertension in the elderly.

Mitochondrial haplogroups A and M7a confer a genetic risk for coronary atherosclerosis in the Japanese elderly: an autopsy study of 1,536 patients

AIM

We previously reported significant associations between mitochondrial single nucleotide polymorphisms (mtSNPs) and myocardial infarction, atherothrombotic cerebral infarction, metabolic syndrome and type 2 diabetes. Here, we assessed the hypothesis that mtSNPs may confer a risk for atherosclerosis, the most important intermediate phenotype of ischemic cardiovascular events.

METHODS

The subjects were 1,536 consecutive autopsy cases (827 men and 709 women). The average age at death was 80 years. The severity of coronary atherosclerosis was semi-quantitatively examined on cut sections. We examined 149 mtSNPs using the PCR-Luminex method, with a success rate of 97%. Phylogenetic tree analysis yielded 36 haplogroups. Multiple logistic regression analysis was performed after adjustments for sex, age, and conventional cardiovascular risk factors.

RESULTS

Among the 45 mtSNPs with minor genotype frequencies >0.05, 6 mtSNPs were associated with coronary atherosclerosis. Among 10 haplogroups with frequencies >0.04, haplogroups A and M7a were significantly associated with coronary atherosclerosis, with odds ratios (95% confidence intervals) of 1.80 (1.09-2.97; p=0.023) and 1.92 (1.23-3.01; p=0.004), respectively. Haplogroup D4a, which was previously reported to be associated with extreme longevity in a Japanese population, was associated with pathological myocardial infarction in men with an odds ratio of 2.05 (1.01-4.14; p=0.046).

CONCLUSIONS

The mitochondrial haplogroups A and M7a confer a significant risk for coronary atherosclerosis in the Japanese. The mitochondrial haplogroup may contribute some genetic risk for coronary heart disease.

Vascular aging: from molecular mechanism to clinical significance

The large and medium-sized arteries in elderly people show varying degrees of intimal and medial change. The medial change is known as age-related medial degeneration and sclerosis (ARMDS). The ARMDS results in systolic hypertension and left ventricular hypertrophy of the heart as a result of loss of arterial elasticity. It also causes aortic dilatation, or even aortic aneurysm. The ARMDS and atherosclerosis are distinct entities, but are often overlapped and confused with each other. The present review mainly focuses on ARMDS and briefly addresses atherosclerosis, and aging of arterioles, capillaries and veins. The smooth muscle cells in the inner half of the aortic media of elderly people degenerate and undergo apoptosis. This causes degradation of elastin fibers and the accumulation of collagen fibers in the media, but the inflammatory infiltrates are scarce. Biochemical studies showed an age-related decrease of elastin and its crosslinks, and an increase of collagen and its crosslink. Because the turnover of elastin is very long, it likely suffers from glycation (Maillard reaction) and glyco-oxidative reaction. The advanced glycation end-products accumulate in the aortic media with increasing age. Alcian-blue positive mucin accumulates in aortic media in elderly people. The major component of the increase of aortic mucin is chondroitin-6-sulfate. Microcalcification is frequent in the inner acellular portion of the aortic media in elderly people. Calcium contents increase with age. In conclusion, the ARMDS is a distinct pathological entity with clinical significance. The pathogenesis of ARMDS is unclear; the mechanical stress of elastin, endothelial dysfunction, and glycation of elastin are proposed.

Systematic review of statins for the prevention of vascular dementia or dementia

AIM

Non-hypolipidemic effects of statins, known as pleiotropic effects, are likely to explain the effect of statins on dementia. Results of the relationship between statins and dementia in previous studies are conflicting. There is no systematic review investigating the effect of statins on vascular dementia (VaD). This systematic review evaluates the role of statins in the prevention of VaD or dementia. The possible causes of conflicting results in the existing published work will be explored.

METHODS

Relevant studies were systematically identified and reviewed. The Cochrane Controlled Trials and three electronic databases (MEDLINE, EMBASE and PsycInfo) were searched. The selection criteria were defined a priori. Included studies were rated by quality assessment checklists and two independent reviewers.

RESULTS

Six studies in dementia, two studies in VaD (one study reported both dementia and VaD) and two meta-analyses met the selection criteria. The studies covered 1372 cases of dementia from 14 430 participants and 116 cases of VaD from 4924 participants from the USA and UK. There was no association between statin use and risk of VaD. The protective effect of statins on dementia was demonstrated only in a nested case-control study of lower quality and one recently published cohort study. In most other cohort and high quality studies, statin use did not show a beneficial effect.

CONCLUSION

Study design differences among the studies and methodological shortcomings may have resulted in different outcomes. On the basis of these conflicting results, statins could not be recommended as a preventative treatment for dementia.

Elderly patients with minimal common carotid atherosclerosis not infrequently have severe coronary atherosclerosis and myocardial infarction

BACKGROUND

The presence of discordances between common carotid and coronary atherosclerosis in the same individual has not been previously reported.

METHODS AND RESULTS

The subjects of the present study were 1,518 consecutive autopsy cases at a general geriatric hospital. All were aged 60 years or older (821 men, 697 women) with an average age of 80 years. The atherosclerotic index of the common carotid artery (CC-AI) and coronary stenotic index (CSI) were semi-quantitatively evaluated. The simple correlation coefficient between the CC-AI and CSI was 0.456 (p<0.0001). Among 689 cases with minimal common carotid atherosclerosis (CC-AI < or =2), 74 (11%) had severe coronary atherosclerosis (CSI > or =12), 68 (10%) had coronary heart disease, and 80 (12%) had pathologically-verified myocardial infarction (MI). Among those with minimal common carotid atherosclerosis, the serum total cholesterol level, diabetes mellitus, and history of smoking were significantly higher or more frequent in cases with a CSI > or =12 than in the patients with a CSI <12.

CONCLUSIONS

A considerable proportion of cases with minimal common carotid atherosclerosis had severe coronary atherosclerosis and MI. This discordance can potentially lead to an underestimation of coronary risks if normal common carotid morphology is obtained by ultrasound.