High serum lipoprotein(a) levels are an independent risk factor for cerebral infarction

Plasma Lipoprotein(a) Levels as Determinants of Arterial Stiffening in Hypertension

Previous studies have shown that plasma lipoprotein(a) (Lp(a)) plays an important role in the development of hypertensive organ damage. The aim of the present study was to investigate the relationship of Lp(a) with markers of arterial stiffening in hypertension. In 138 essential hypertensive patients free of diabetes, renal failure and cardiovascular complications, we measured plasma lipids and assessed vascular stiffness through the use of pulse wave analysis and calculation of the brachial augmentation index (AIx), and measured the pulse wave velocity (PWV). Plasma Lp(a) levels were significantly and directly related to both AIx (r = 0.490; p < 0.001) and PWV (r = 0.212; p = 0.013). Multiple regression analysis showed that AIx was independently correlated with age, C-reactive protein, and plasma Lp(a) (beta 0.326; p < 0.001), while PWV was independently and directly correlated with age, and inversely with HDL, but not with plasma Lp(a). Logistic regression indicated that plasma Lp(a) could predict an AIx value above the median for the distribution (p = 0.026). Thus, in a highly selective group of patients with hypertension, plasma Lp(a) levels were significantly and directly related to markers of vascular stiffening. Because of the relevance of vascular stiffening to cardiovascular risk, the reduction of Lp(a) levels might be beneficial for cardiovascular protection in patients with hypertension.

Lipoprotein (a) level as a risk factor for stroke and its subtype: A systematic review and meta-analysis

The role of lipoprotein-A [Lp (a)] as a risk factor for stroke is less well documented than for coronary heart disease. Hence, we conducted a systematic review and meta-analysis for the published observational studies in order to investigate the association of Lp (a) levels with the risk of stroke and its subtypes. In our meta-analysis, 41 studies involving 7874 ischemic stroke (IS) patients and 32,138 controls; 13 studies for the IS subtypes based on TOAST classification and 7 studies with 871 Intracerebral hemorrhage (ICH) cases and 2865 control subjects were included. A significant association between increased levels of Lp (a) and risk of IS as compared to control subjects was observed (standardized mean difference (SMD) 0.76; 95% confidence interval (CIs) 0.53-0.99). Lp (a) levels were also found to be significantly associated with the risk of large artery atherosclerosis (LAA) subtype of IS (SMD 0.68; 95% CI 0.01-1.34) as well as significantly associated with the risk of ICH (SMD 0.65; 95% CI 0.13-1.17) as compared to controls. Increased Lp (a) levels could be considered as a predictive marker for identifying individuals who are at risk of developing IS, LAA and ICH.

Lipoprotein(a) predicts a new onset of chronic kidney disease in people with Type 2 diabetes mellitus

AIMS

We investigated the association between lipoprotein(a) [Lp(a)] level and new-onset chronic kidney disease (CKD) in patients with Type 2 diabetes.

METHODS

We conducted a prospective cohort study from March 2003 to December 2004 with a median follow-up time of 10.1 years. Patients aged 25-75 years with Type 2 diabetes and without CKD [estimated glomerular filtration rate (eGFR) ≥ 90 ml/min/1.73 m(2) ) were consecutively enrolled. The eGFR was measured at least twice every year , and new-onset CKD was defined as a decreased eGFR status of < 60 ml/min/1.73 m(2) using a Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.

RESULTS

Of the 862 patients who were enrolled, 560 (65.0%) completed the follow-up and 125 (22.3%) progressed to CKD. The mean age and duration of diabetes were 53.3 ± 9.6 and 7.5 ± 6.0 years, respectively. The baseline eGFR was 101.8 ± 11.3 ml/min/1.73 m(2) . After adjusting for multiple confounding factors, a Cox hazard regression analysis revealed that the third tertile of Lp(a) was significantly associated with the development of CKD during the observation period when compared with the first tertile [hazard ratio 2.12 (95% confidence interval 1.33-3.36); P = 0.001).

CONCLUSIONS

In this prospective, longitudinal, observational cohort study, we demonstrated that the Lp(a) level was an independent prognostic factor for the future development of CKD in patients with Type 2 diabetes.

Lipoprotein (a) as a risk factor for ischemic stroke: a meta-analysis

OBJECTIVE

Lipoprotein (a) [Lp(a)] harbors atherogenic potential but its role as a risk factor for ischemic stroke remains controversial. We conducted a meta-analysis to determine the relative strength of the association between Lp(a) and ischemic stroke and identify potential subgroup-specific risk differences.

METHODS

A systematic search using the MeSH terms "lipoproteins" OR "lipoprotein a" AND "stroke" was performed in PubMed and ScienceDirect for case-control studies from June 2006 and prospective cohort studies from April 2009 until December 20th 2014. Data from eligible papers published before these dates were reviewed and extracted from previous meta-analyses. Studies that assessed the relationship between Lp(a) levels and ischemic stroke and reported generic data-i.e. odds ratio [OR], hazard ratio, or risk ratio [RR]-were eligible for inclusion. Studies that not distinguish between ischemic and hemorrhagic stroke and transient ischemic attack were excluded. Random effects meta-analyses with mixed-effects meta-regression were performed by pooling adjusted OR or RR.

RESULTS

A total of 20 articles comprising 90,904 subjects and 5029 stroke events were eligible for the meta-analysis. Comparing high with low Lp(a) levels, the pooled estimated OR was 1.41 (95% CI, 1.26-1.57) for case-control studies (n = 11) and the pooled estimated RR was 1.29 (95% CI, 1.06-1.58) for prospective studies (n = 9). Sex-specific differences in RR were inconsistent between case-control and prospective studies. Study populations with a mean age of ≤55 years had an increased RR compared to older study populations. Reported Lp(a) contrast levels and ischemic stroke subtype significantly contributed to the heterogeneity observed in the analyses.

CONCLUSION

Elevated Lp(a) is an independent risk factor for ischemic stroke and may be especially relevant for young stroke patients. Sex-specific risk differences remain conflicting. Further studies in these subgroups may be warranted.

Risk factors for cerebral arteriosclerosis in Parkinson's disease

A previous study showed a lower incidence of ischemic stroke in patients with Parkinson's disease (PD) than in controls. It has been speculated that this may be related to less severe atherosclerosis in PD. In this study we examined the magnetic resonance imaging (MRI) and blood chemistry in 106 parkinsonian patients and compared the data with those from control cases. Abnormal MRI findings (état criblé, lacunar infarctions or periventricular hyperintensity) were found in 55.7% of cases. No case of cortical artery infarction was found. In comparison with a control population, the PD group showed a lower frequency of hypercholesterolemia, a higher frequency of low HDL cholesterol and a lower frequency of obesity. These results suggest that patients with PD have a reduction in risk factors for cortical artery infarction.

Lipoprotein(a) and inflammation in patients with atrial fibrillation after electrical cardioversion

Background

Recently few studies tried to confirm the association between AF and lipoprotein(a) (Lp(a)), however the results remained conflicted. In present study we evaluated the possible interaction between Lp(a), inflammatory state and echocardiographic characteristics in patients after successful electrical cardioversion (EC) of persistent AF. We also tried to investigate the role of Lp(a) as a possible prognostic factor for AF recurrence after successful EC.

Results

Data of 79 patients admitted due to planned EC was analyzed. After successful procedure patients were monitored for 2 years. For analytical purposes patients were divided in two groups according to AF recurrence. There was no significant difference between Lp(a) levels in both groups. We also didn't find any positive correlation between Lp(a) and CRP levels, as well as between Lp(a) levels and left atrium diameter. For logistic and survival analysis optimal cut-off value of Lp(a) ≥ 0.32 (upper quartile) was used. In logistic regression model with AF recurrence as dependent variable Lp(a) didn't show any statistically significant association with AF recurrence. Survival analysis showed slightly higher AF recurrence rate in group with higher Lp(a) levels but not to the level of statistical significance (log rank test, p = 0.62).

Conclusions

We weren't able to confirm the association between Lp(a) levels and AF recurrence, inflammation and left atrium diameter in patients after successful EC of persistent AF. Further studies are needed to elucidate the role of Lp(a) in this clinical setting.

Young strokes in Sri Lanka: an unsolved problem

Stroke in young adults is more common in India and Sri Lanka and the reasons for this are not well understood. The current study was conducted to elucidate the risk factors and radiologic features in young people (age < 45 years) with ischemic stroke. Sociodemographic data, stroke risk factor information, and laboratory investigations were recorded in 41 cases with first-ever ischemic stroke. Most common risk factors for stroke in the 15- to 45-year-old age group were: hypertension, 8 (21%); family history of stroke, 7 (18%); transient ischemic attack, 6 (16%); hyperlipidemia, 3 (8.0%); and diabetes, two (5%). Age group younger than 15 years included 3 girls and one had a mass attached to the posterior mitral valve leaflet. Our observations underscore the importance of the presence of hypertension, family history of stroke, and transient ischemic attack in young adults and thus to adopt preventative strategies.

Family history and risk for ischemic stroke: sibling history is more strongly correlated with the disease than parental history

Current data concerning the association between family history and the risk for developing stroke have been controversial. There has been very little data on the influence of family history on intracranial atherosclerosis (ICAS), stroke severity, and recovery, especially among Asian populations. We evaluated the association between family history and the risk for stroke and investigated the relationships between family history and ICAS, stroke severity, and short-term stroke outcome in Korean stroke patients. In this case-control study, we recruited 400 patients with acute ischemic stroke, along with the same number of age- and gender-matched control subjects. Assessments of first-degree family history of stroke, myocardial infarction, hypertension and diabetes mellitus were obtained by structured questionnaires, followed by reviews of the clinical and neuro-radiological findings of the stroke patients. A family history of stroke was associated with an increased risk of ischemic stroke (OR, 2.65; 95% CI, 1.75 to 4.01), and the correlation remained significant after multivariate analysis. The odds ratios of paternal, maternal, and sibling history were 2.07, 2.16, and 4.21, respectively. The risk of stroke did not differ significantly with the presence of ICAS, stroke severity, and stroke outcome. Family history of stroke was an independent risk factor for ischemic stroke. A positive sibling history was more strongly correlated with the incidence of stroke than a positive parental history, and this finding may indicate the possible role of environmental factors in a shared household in addition to the genetic factors involved in family medical history.

Elevated Lp(a) with a small apo(a) isoform in children: risk factor for the development of premature coronary artery disease

BACKGROUND

levels of Lp(a) and low-molecular-weight apolipoprotein(a) isoform are strongly associated with the development of early cardiovascular disease. Certain types of apo(a) isoforms in combination with elevated levels of Lp(a) may be important in the determining of premature coronary artery disease. Therefore, we investigated the association of familial history of premature coronary artery disease and apo(a) size and Lp(a) levels in children and adolescents with hypercholesterolemia using a novel method determining apo(a) isoforms.

METHODS AND RESULTS

Isoforms were classified in six phenotype patterns: S1-S4, B, F and according to their K-IV repeats. Apo(a) isoforms were divided into two groups: low-molecular- and high-molecular apo(a) isoforms. In subjects with double-banded apo(a) isoforms containing a small- and a large-isoform Lp(a) each contribution was based on the intensity of staining of the two bands. The percentage of patients with elevated levels of Lp(a) and a small apo(a) isoform (i.e. elevated small-isoform Lp(a)) was 46% in the risk group and 20% in the control group, p < 0.05. The percentage number of children and adolescents with elevated Lp(a) levels was higher in the risk group, reaching statistical significance (p < 0.05).

CONCLUSION

Elevated levels of small-isoform Lp(a) might be a strong and independent risk factor for the development of premature coronary artery disease in children and adolescents with hypercholesterolemia.

Relationship of apoE polymorphism with lipoprotein(a), apoA, apoB and lipid levels in atherosclerotic infarct

BACKGROUND AND PURPOSE

Apolipoprotein E (apoE) polymorphism is suggested to be a risk factor in stroke in some populations, either by affecting lipid parameters or independently. Its effect on lipoprotein(a) [Lp(a)] is not known. The roles of apoE polymorphism and of high Lp(a) levels in atherosclerotic stroke (AS) in the Turkish population are unclear. Our aim was to investigate the relationship of apoE alleles and Lp(a) level with AS and the relationship of apoE alleles with Lp(a) and other lipid parameters.

METHODS

ApoE polymorphisms and lipid parameters were prospectively evaluated in 85 patients and 77 controls with normal brain imaging.

RESULTS

Only hypertension, diabetes mellitus, associated vascular diseases and decreased high-density lipoprotein cholesterol levels were found to be independent risk factors for stroke. However, in the presence of apoE/E4 allele, increased low-density lipoprotein cholesterol (LDL-chol), apolipoprotein B (apoB) and Lp(a) levels and in the presence of apo E/E3 allele, only Lp(a) levels were determined as risk factors.

CONCLUSION

This study showed that while apoE polymorphism was not a risk factor itself, high Lp(a), LDL-chol and apoB were determined to be risk factors in E3 or E4 carriers.

Different apoprotein(a) isoform proportions in serum and carotid plaque

INTRODUCTION

Cardio- and/or cerebro-vascular risk are associated with high lipoprotein (a) [Lp(a)] levels and low-molecular-weight (LMW) apo(a) isoforms. Aims of this study were to evaluate the deposition of apo(a) isoforms and apoprotein B (apo B) in atherosclerotic plaque from patients (males and females) who had carotid endarterectomy for severe stenosis, and to identify differences between patients classified by gender and divided according to the stability or instability of their plaques.

MATERIALS AND METHODS

We determined lipids, apo B and Lp(a) in serum and plaque extracts from 55 males and 25 females. Apo(a) was phenotyped and isoforms were classified by number of kringle IV (KIV) repeats.

RESULTS

Lp(a) levels were higher in female serum and plaque extracts than in male samples, while apo B levels were lower. More Lp(a) than apo B deposition was observed in plaque after normalization for serum levels. Thirty-one different apo(a) isoforms were detected in our patients, with a double band phenotype in 94% of cases. In both sexes, the low/high (L/H) molecular weight apo(a) isoform expression ratio was significantly higher in plaque than in serum. Females with unstable plaques had higher Lp(a) levels in both serum and tissue extracts, and fewer KIV repeats of the principal apo(a) isoform in the serum than the other female group or males.

CONCLUSIONS

In both sexes, the same apo(a) isoforms are found in serum and atherosclerotic plaque, but in different proportions: in plaque, LMW apo(a) is almost always more strongly accumulated than HMW apo(a), irrespective of any combination of apo(a) isoforms in double band phenotypes or Lp(a) serum levels. Moreover, serum and tissue Lp(a) levels were higher in females than in males, and particularly in the group with unstable plaques.

Moya moya syndrome in a child with pyruvate kinase deficiency and combined prothrombotic factors

A 13-year-old Greek girl with pyruvate kinase deficiency and moya moya angiographic pattern is reported. She also had raised serum lipoprotein (a) concentration and was homozygous for the C677T mutation of the methylenetetrahydrofolate reductase gene. She presented with neonatal onset of anemia, hemolytic and aplastic crises, especially during infections, stroke, and also progressive motor and mental deterioration. A digital cranial angiography at 13 years revealed the typical angiographic findings of moya moya angiopathy. This is likely the first patient with pyruvate kinase deficiency and moya moya syndrome and also the combination of elevated serum lipoprotein (a) concentration and the C677T mutation of the methylenetetrahydrofolate reductase gene to be reported. In patients with pyruvate kinase deficiency and moya moya syndrome, a search for raised serum lipoprotein (a) concentrations and the C677T mutation of the methylenetetrahydrofolate reductase gene should be considered.

Lp(a) lipoprotein and plasminogen activity in patients with different etiology of ischemic stroke

BACKGROUND AND PURPOSE

Lp(a) lipoprotein plays an important part in atherothrombogenesis and is considered an independent risk factor for coronary heart disease. However, its role in cerebrovascular disease remains unclear, in particular because of the heterogeneous nature of strokes. We investigated whether elevated Lp(a) is more frequent in ischemic stroke related to atherothrombosis than in other etiologies of stroke. Because of the close structural homology between Lp(a) and plasminogen, we also studied the role of plasminogen in different stroke subtypes and whether there is a dependency on Lp(a) plasma levels.

METHODS

Lp(a) levels and plasminogen activity were measured in 253 consecutive patients with acute ischemic stroke and in 63 controls (CS). Subtypes of stroke were established according to the TOAST criteria.

RESULTS

Median Lp(a) levels were found to be higher in the total cerebral infarction group and in patients with large artery atherosclerosis (LAA) when compared with CS (20.9 and 22.0 mg/dl, respectively, vs. 16.0 mg/dl; p < 0.05). In addition, elevated Lp(a) levels >30 mg/dl were more frequent among the LAA subgroup than among CS (39.4 vs. 11.1%; p < 0.001). Mean plasminogen activity was lower in the total cerebral infarction group (110.8 vs. 120.3%; p < 0.001) and in patients with cardioembolic stroke (109.8 vs. 120.3%; p < 0.05) when compared with CS. There was no correlation between Lp(a) levels and plasminogen activity.

CONCLUSIONS

Our results support the hypothesis that elevated Lp(a) is a risk factor for ischemic stroke and especially for strokes caused by LAA. Low plasminogen activity may play a role in the pathogenesis of cerebrovascular disease, especially for the development of cardioembolic stroke.

Serum lipoprotein(a) levels and apolipoprotein(a) isoform size and risk for first-ever acute ischaemic nonembolic stroke in elderly individuals

In a population-based case-control study, we investigated the association of acute ischaemic stroke with lipoprotein(a) (Lp(a)) levels and apolipoprotein (Apo) (a) isoform size in subjects aged older than 70 years. A total of 163 patients with a first-ever-in-a-lifetime acute ischaemic/nonembolic stroke and 166 controls were included. Compared to controls, stroke patients exhibited higher Lp(a) concentrations (median value, 12.2 mg/dl versus 6.4 mg/dl, p < 0.001) and a higher frequency of small Apo(a) isoforms (44.2% versus 29.5%, p < 0.01). Multivariate logistic regression analysis showed a significant association of acute ischaemic stroke with Lp(a) levels [adjusted odds ratio (OR), 1.37, 95% CI (1.12-1.67); p = 0.002], and small Apo(a) isoform size [OR, 1.74 (1.10-3.03); p = 0.04]. Compared to subjects with Lp(a) levels in the lowest quintile, those within the highest quintile had a 3.2-times adjusted risk to suffer an acute ischaemic/nonembolic stroke (1.60-6.62, 95% CI; p < 0.001). Furthermore, analysis of interaction between lipid variables revealed that in the presence of elevated Lp(a) levels the inverse relationship between HDL-cholesterol levels and ischaemic stroke was negated [OR, 1.01 (1.00-1.03); p = 0.015]. Our study suggests that determination of Lp(a) levels and Apo(a) isoform size may be important in identifying elderly individuals at risk of ischaemic stroke independently of other risk factors and concurrent metabolic derangements.

Lipids and stroke: the opportunity of lipid-lowering treatment

Dyslipemia is a clear risk factor (RF) for ischemic heart disease and peripheral artery disease, but its relation with ischemic stroke (IS) is not so clear. HMG-CoA reductase inhibitor drugs or statins (simvastatin, atorvastatin, pravastatin) reduce the relative risk of IS by between 18 and 51% in patients with IHD, in patients with high vascular disease risk and in hypertensive patients with other RFs, acute coronary syndrome, and type 2 diabetes mellitus. According to the guidelines for use, statins are indicated in the majority of patients with IS since the risk is equivalent to that of IHD or high vascular disease risk. In view of the existing clinical evidence of benefit, it would not seem unreasonable to proceed with treatment of patients using statins while awaiting specific studies justifying their use. The non-lipid-lowering mechanisms of the statins and results of studies, such as the Heart Protection Study, provide evidence for widening the indications of statins beyond the prevention of dyslipemia, as a new therapeutic approach in the prevention of IS in patients with plasma levels of total cholesterol or low density lipoproteins currently considered within the normal distribution. The neuroprotective role, which these drugs may play in the acute phase of cerebral ischemia, remains to be clarified, but very recent evidence suggests that such patients may also benefit.

Plasma lipoprotein(a) [Lp(a)] concentrations and cardiovascular events in the elderly: evidence from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER)

Using analyses of the large cohort (n=5732) from the prospective study of pravastatin in the elderly at risk (PROSPER), we tested the hypothesis that Lp(a) concentration is an independent predictor of major vascular events and cognitive impairment in the elderly. Baseline Lp(a) levels were measured on fresh samples from 5732 subjects aged 70-82, who were followed for 3.2 years on average. Lp(a) levels were not significantly different across the age range in PROSPER, but were significantly higher in women (geometric mean 14.8 versus 12.4 mg/dl, P<0.0001). Those with a history of vascular disease had significantly higher Lp(a) levels, which remained after adjustment (P<0.0001). There was no statistically significant association between baseline Lp(a) and the risk of the primary endpoint (CHD death, non-fatal MI and fatal or non-fatal stroke) (hazard ratio 1.05, 95% CI 1.00-1.11, P=0.077), but after adjustment for baseline risk factors this did achieve statistical significance (1.06, 1.005-1.12, P=0.032). Finally, there was no statistically or clinically significant association between any adjusted baseline or dynamic cognition variables and Lp(a), and nor was there any significant association between Lp(a) and indices of disability throughout the study. This is the first study of the association between Lp(a) and a range of cardiovascular endpoints including cognitive and disability indices in the elderly. The main finding is that Lp(a) level, while influenced by a number of baseline characteristics, is not a significant predictor of cognitive function or levels of disability, but is a predictor of combined cardiovascular events over an average 3.2 year follow-up.

Long-Term Effects of Lipoprotein(a) on Carotid Atherosclerosis in Elderly Japanese

BACKGROUND

Serum level of lipoprotein(a) [Lp(a)] is hereditarily constant throughout life within an individual, but the relationship between Lp(a) and atherosclerosis in elderly people is still controversial.

METHODS

Serum Lp(a) levels were studied in 208 elderly Japanese participants aged 80 years with a variety of diseases, using carotid ultrasonography (US), brain computerized tomography (CT), electrocardiography (ECG), and ankle brachial pressure index (ABPI). Carotid plaque lesions were divided into 3 types based on the US echogenicity assessed by a computer-assisted system: L type (hypoechoic plaque), H type (hyperechoic plaque), and M type (heterogeneous plaque).

RESULTS

The frequency of the L type and occlusion was significantly higher in the high Lp(a) group (n = 38) than in the normal Lp(a) group (n = 170). The mean height of the plaque was also greater in the high Lp(a) group than in the normal Lp(a) group. There was no difference in CT findings between the two groups. Myocardial ischemia on ECG and low ABPI (<0.9) were both frequently, but not significantly, seen in the high Lp(a) group. Among factors influencing US findings, multiple regression analysis showed that high Lp(a) correlated markedly to L type and cigarette smoking correlated to M type.

CONCLUSIONS

These findings indicate that, in Japanese elderly patients aged 80, serum Lp(a) strongly correlates with hypoechoic carotid lesions, which correspond histologically to lipid-rich, unstable atherosclerosis. This suggested that Lp(a) could promote the formation of atherosclerosis throughout life, and play a role as an independent risk factor for circulatory disturbance of the organ later in life.

Lp(a) lipoprotein, vascular disease, and mortality in the elderly

BACKGROUND

As compared with what is known about predictors of vascular events in middle-aged persons, less is known about these events in the elderly. Lp(a) lipoprotein, which plays an important part in atherothrombogenesis, has been associated with an increased risk of vascular disease. We investigated this relation among older U.S. adults.

METHODS

In a prospective study of 5888 community-dwelling older adults (65 years of age or older) in the United States, 2375 women and 1597 men who were free of vascular disease provided base-line serum samples for analysis for levels of Lp(a) lipoprotein. These 3972 subjects were followed for a median of 7.4 years to evaluate the development of stroke and to track deaths from vascular causes and all causes. The men and women were divided into quintile groups according to the Lp(a) lipoprotein level at base line.

RESULTS

Using Cox proportional-hazards models, we determined the risk associated with each quintile level of Lp(a) lipoprotein, with the lowest quintile serving as the reference group. As compared with those in the lowest quintile, men in the highest quintile had three times the unadjusted risk of stroke (relative risk, 3.00; 95 percent confidence interval, 1.59 to 5.65), almost three times the risk of death associated with vascular events (relative risk, 2.54; 95 percent confidence interval, 1.59 to 4.08), and nearly twice the risk of death from all causes (relative risk, 1.76; 95 percent confidence interval, 1.31 to 2.36). Adjustment for age; sex; the levels of total cholesterol, low-density lipoprotein cholesterol, and triglycerides; carotid-wall thickness; smoking status; the presence or absence of diabetes and systolic and diastolic hypertension; body-mass index; and other traditional risk factors had little effect on the final assessments. Similar analyses for women, which also included adjustment for estrogen use or nonuse, revealed no such relation.

CONCLUSIONS

Among older adults in the United States, an elevated level of Lp(a) lipoprotein is an independent predictor of stroke, death from vascular disease, and death from any cause in men but not in women. These data support the use of Lp(a) lipoprotein levels in predicting the risk of these events in older men.

Lipoprotein (a) in childhood: correlations with family history of cardiovascular disease

The association between lipoprotein (a) [Lp(a)] and cardiovascular diseases is well known. Lp(a) is an independent risk factor for the development of atherosclerosis. Little information concerning Lp(a) during childhood is available. The aim of the present investigation was to determine the Lp(a) concentration in a cohort of children aged between 4 and 15 yr and to correlate Lp(a) with: a) overweight status; b) body fat distribution; c) family history of vascular diseases in their parents and grandparents. Six hundred and eighty-nine children (350 males, 339 females), were enrolled in the study. BMI as index of being overweight was calculated; the waist-to-hip ratio (WHR) and the waist-to-thigh ratio (WTR) were calculated to obtain two anthropometric indexes for the pattern of body fat distribution. The areas of visceral (VAT) and subcutaneous adipose tissue (SAT) were evaluated by MRI at the L4-L5 level in only 30 overweight subjects. The serum of Lp(a), total cholesterol (TC), HDL-cholesterol, LDL-cholesterol and triglycerides were evaluated in the whole population. Moreover, the same biochemical study was performed in 70 children's parents randomly chosen. A structured questionnaire was administered to the children's parents to investigate the presence of cardiovascular disease (CVD) in family stories. Our data show no Lp(a) serum differences between children according to sex, age and body composition. The strong correlation between the children's and the parents' Lp(a) concentrations and the occurrence of CVD in their grandparents suggests that Lp(a) represents an important independent early risk factor for the development of CVD in adulthood. Measurements of Lp(a) in childhood may help to evaluate this risk in subjects with family history of cardiovascular diseases.

Serum lipoprotein(a) concentrations and alcohol consumption in hypertension: possible relevance for cardiovascular damage

OBJECTIVES

To evaluate the relationships between alcohol intake and serum lipoprotein(a) [Lp(a)], a powerful predictor of organ damage, in patients with essential hypertension with a wide range of alcohol intake, and to investigate whether the association between alcohol intake and serum Lp(a) concentrations occurs over the entire spectrum of apo(a) phenotypes.

DESIGN

Cross-sectional study of a case series.

SETTING

University medical centre.

PATIENTS

Four hundred and two patients with untreated essential hypertension recruited at a hypertension clinic.

MAIN OUTCOME MEASURES

Serum Lp(a) concentrations, apo(a) isoforms, alcohol consumption, smoking habits and cardiovascular status.

RESULTS

No difference in Lp(a) concentrations was observed between teetotalers and occasional drinkers. Light drinkers (1-20 g/day ethanol), moderate drinkers (21-50 g/day), and heavy drinkers (> 50 g/day) had, respectively, 21, 26 and 57% lower median Lp(a) concentrations than teetotalers and occasional drinkers. Similar findings were obtained when male and female patients were analysed separately. Log Lp(a) concentrations were inversely and independently correlated with alcohol consumption in both men and women with hypertension. The frequency distributions of apo(a) isoforms and liver function parameters were comparable across the different alcohol intake groups. Patients with evidence of cardiovascular damage had greater concentrations of serum Lp(a) and higher frequency of low-molecular weight apo(a) isoforms as compared with patients without such evidence.

CONCLUSIONS

Serum Lp(a) is inversely and dose-dependently related with alcohol intake in patients with hypertension, and this relationship is independent of the size distribution of apo(a) isoforms. Reduction of Lp(a) concentrations by regular consumption of alcohol might favourably affect the atherosclerotic risk profile of patients with hypertension and thereby decrease cardiovascular morbidity.

Stroke: a review with an African perspective

The frequency of stroke and stroke-associated mortality are higher in Blacks than in other races. Several of the known risk factors for stroke, such as hypertension, diabetes and obesity, are more common in Blacks than Whites, and sickle-cell disease and HIV infection are stroke risk factors with particular relevance to Africans. Although the facilities for accurate stroke diagnosis and classification are unavailable in most parts of Africa, careful analysis of the clinical features can minimize the rates of misdiagnosis and misclassification. The high levels of stroke-attributable morbidity and mortality observed in Africans could be markedly reduced by instituting primary and secondary preventive measures and by educating health-care professionals on stroke-management strategies.

Relation of lipid and lipoprotein(a) to ischaemic stroke

The relationship of lipids and Lp(a) to ischemic stroke hasn't been established yet. Our aim was to determine lipid profile and vascular risk factors in stroke patients and compare them with control subjects. Seventy-nine consecutive patients with ischemic stroke were analyzed by total cholesterol, HDL-C, LDL-C, triglyceride, Lp(a) and doppler ultrasonography and vascular risk factors were recorded. Thirty control subjects of same ages were compared with the patient group. Lp(a) and lipids were correlated with stroke subtype and carotid atherosclerosis. There was no statistical significance between patients and control subjects related to total cholesterol, triglyceride, HDL-C, LDL-C and Lp(a) (P>0.05). Atherotrombotic and lacunar strokes didn't show any difference correlated with lipids and Lp(a). Hypertension and diabetes mellitus were important risk factors with (OR=4.50, 95% CI=1.25-16.22) and (OR=4.43, 95% CI=1.79-10.93) respectively. These results were statistically significant (P<0.05). Total cholesterol (308.67+/-85.82) and Lp(a) (32.10+/-17.30) values showed statistical significance (P<0.05) in patients with marked stenosis when compared with patients of normal doppler ultrasonography. Hypertension and diabetes mellitus were found as independent risk factors for ischemic stroke. Lipids and Lp(a) were not independent for atherotrombotic and lacunar stroke. Lp(a) concentration and carotid atherosclerosis in ultrasonography were associated significantly.

Stimulation of interleukin-8 production in human THP-1 macrophages by apolipoprotein(a). Evidence for a critical involvement of elements in its C-terminal domain

In the vessel wall, macrophages are among the cells that upon activation contribute to the atherosclerotic process. Low density lipoproteins (LDL) can mediate this activation but only after enzymatic or oxidative modification. Lipoprotein(a) (Lp(a)) is an LDL variant that has been shown to have an atherogenic potential by no clearly established mechanisms. In the present study we examined whether native Lp(a) can activate macrophages and, if so, identify the structural elements involved in this action. For this purpose, we utilized human THP-1 macrophages, prepared by treating THP-1 monocytes with phorbol ester, and we exposed them to Lp(a) and its two derivatives, apo(a)-free LDL (Lp(a-)) and free apo(a). We also studied apo(a) fragments, F1 (N terminus) and F2 (C terminus) and subfragments thereof, obtained by leukocyte elastase digestion. By Northern blot analyses, Lp(a), but not Lp(a-), caused up to a 12-fold increase in interleukin 8 (IL-8) mRNA as compared with untreated cells. Free apo(a) also induced the production of IL-8 mRNA; however, the effect was 3-4-fold higher than that of Lp(a). The increase in mRNA was associated with the accumulation of IL-8 protein in the culture medium. F1 had only a minimal effect, whereas F2 was 1.5-2-fold more potent than apo(a), an activity mostly contained in the Kringle V-protease region. A monoclonal antibody specific for Kringle V inhibited the apo(a)-mediated effect on IL-8. We conclude that Lp(a) via elements contained in the C-terminal domain of apo(a) causes in THP-1 macrophages an increased production of IL-8, a chemokine with pro-inflammatory properties, an event that may be relevant to the process of atherosclerosis.

Detection of lipoprotein(a) in intraparenchymal cerebral vessels: correlation with vascular pathology and clinical history

Serum levels of lipoprotein(a), Lp(a), have been shown to be associated with increased risk of atherosclerosis (AS) and AS-related diseases such as myocardial and ischemic cerebral infarcts (ICI). Lp(a) has been detected in the vascular wall of the aorta and coronary vessels, and we documented the presence of apo(a) in cerebral vessels of the Circle of Willis, associated with AS changes. In this study we further investigated and characterized the biochemical nature of Lp(a) detected in both large and small cerebral parenchymal vessels. Autopsy specimens of cerebral vessels of 51 patients were examined by immunohistochemistry with monoclonal antibodies against apo(a), apoB, and plasminogen. Lp(a) was detected in cerebral capillaries and arterioles. All of the 8 patients with ICI expressed Lp(a) in parenchymal vessels, generally (6/8) in both capillaries and arterioles. Of 43 patients without ICI only 25 had Lp(a) detected. Among the patients without ICI, there was a slightly increased incidence of parenchymal Lp(a) in those patients who had severe hypoxic brain damage (12/20) compared to those patients without severe hypoxic damage (9/23). Thus, the presence of Lp(a) in small cerebral parenchymal vessels may reflect the role of Lp(a) in ICI.

Lipoprotein(a) serum levels and vascular diseases in an older Caucasian population cohort. Italian Longitudinal Study on Aging (ILSA)

OBJECTIVE

To investigate elevated lipoprotein(a) [Lp(a)] levels as a risk factor for stroke, myocardial infarction, angina, intermittent claudication, and combination of the above in a cohort of unselected older individuals.

DESIGN

Population cohort from one of the eight centers participating in the Italian Longitudinal Study on Aging (ILSA).

SETTING

General community.

PARTICIPANTS

A subsample of 446 subjects (M/F: 231/ 215, mean age: 74.5 +/- 5.7 years) of the original, randomly selected, population cohort of 704 individuals, 65 to 84 years of age, free-living or institutionalized in the Impruneta Municipality, area of Florence, Italy.

MEASUREMENTS

Conventional vascular risk factors and vascular diseases defined following a two-step procedure (screening phase and confirmation on positives) using standard and validated criteria. Lp(a) levels determined by an ELISA method.

RESULTS

No association was observed between elevated Lp(a) levels alone and any of the examined vascular diseases (stroke, myocardial infarction, angina, and intermittent claudication). In contrast, examining the interactions between elevated Lp(a) and conventional vascular risk factors, when elevated Lp(a) was combined with a history of smoking, a marked increase in the risk of vascular diseases combined (odds ratio [OR]: 4.12; 95% confidence interval [CI]: 1.27-13.40) was observed, much higher than that expected based on the additive effect of smoking and elevated Lp(a) alone.

CONCLUSIONS

With the cautions due to the cross-sectional design of the study and the limited statistical power, these results suggest a possible synergistic effect between elevated Lp(a) levels and other pro-atherogenic factors such as smoking on the risk of vascular diseases in older individuals.

Relationship of lipoprotein(a) to variables of coagulation in hypertensive subjects

BACKGROUND

Coagulation factors are independent predictors of cardiovascular damage in the general population. The purpose of this study was to investigate the relationships between general cardiovascular risk factors, lipoprotein(a) (Lp(a)), and some hemostatic variables, and to characterize the isoforms of apolipoprotein(a) (apo(a)) in hypertensive subjects.

METHODS

Plasma lipids, apolipoproteins, Lp(a), apo(a) isoforms, fibrinogen, and parameters that directly reflect the coagulation activation were measured in 389 untreated essential hypertensive patients recruited at a hypertension clinic. Hypertensive patients were compared with 323 normotensive controls.

RESULTS

In normotensive subjects, Lp(a) concentrations were significantly correlated with fibrinogen (r = 0.138; P < 0.02) but not D-dimer (r = 0.074; not significant). In hypertensive subjects, log Lp(a) concentrations were significantly correlated with age (r = 0.127; P < 0.02), apo-B (r = 0.128; P < 0.02), plasma fibrinogen (r = 0.193; P < 0.001), and fibrin D-dimer (r = 0.200; P < 0.001) levels, but not with body mass index, blood pressure, cholesterol, triglycerides, apo-AI, prothrombin fragment 1 + 2, and antithrombin III. The relationship of Lp(a) with fibrinogen (male: r = 0.198, P < 0.002; female: r = 0.177, P < 0.01) and D-dimer (male: r = 0.211, P < 0.002; female: r = 0.188, P < 0.01) was significant in both sexes, whereas the relationship of Lp(a) with age and apo-B was found only in males. Multivariate analysis showed that both fibrinogen and D-dimer were independently related with Lp(a). Elevated fibrinogen, D-dimer, and Lp(a) levels were significantly and independently associated with clinical evidence of atherosclerotic disease. Apo(a) phenotypes were analyzed to investigate the genetic background of the relationships between Lp(a) and coagulation parameters. In both hypertensive and normotensive subjects, Lp(a) levels were inversely correlated with apo(a) isoform protein size, whereas fibrinogen and D-dimer concentrations were comparable in patients with apo(a) isoforms of different size.

CONCLUSIONS

The relationship between Lp(a) and clotting variables is significantly stronger in hypertensive than in normotensive subjects, providing a compelling argument for accelerated progression of atherothrombosis in these patients.

Apolipoprotein (a) fragments in relation to human carotid plaque instability

PURPOSE

An elevated plasma level of lipoprotein (a) is an independent risk factor for atherothrombotic cardiovascular disease by yet undefined mechanisms. We have previously reported that matrix metalloproteinases cleave apolipoprotein (a) into 2 main fragments, F1 and F2, the latter (the C-terminal domain) exhibiting in vitro a high-affinity binding to extracellular matrix components, including fibrin(ogen). We therefore tested the hypothesis that the lipoprotein (a) matrix metalloproteinase-derived F2 is localized in potentially or morphologically unstable human carotid plaque at regions of increased matrix metalloproteinase activity.

METHODS

Carotid plaques removed after endarterectomy (n = 18) were evaluated for structural features indicative of instability (thin fibrous cap, inflammation, and proximity of the necrotic core to the lumen); each plaque was classified as unstable (n = 10) or stable (n = 8). Western blot analysis was performed to quantitate apolipoprotein (a) and its fragments F1 and F2 in plaque extracts. Immunohistochemical staining was used to localize apolipoprotein (a) and its fragments within the atherosclerotic plaque. In situ zymography was used to determine regions of gelatinase (matrix metalloproteinase 2 and matrix metalloproteinase 9) activity.

RESULTS

Western blot analyses demonstrated a 2.5-fold higher density of F2 in unstable plaques than in stable plaques (3.07 +/- 1.9 vs 1.18 +/- 0.8; P <.05). In morphologically unstable plaques, there was preferential distribution of F2 within regions of fibrous cap inflammation and/or foam cell accumulation and within abluminal necrotic cores. In morphologically stable plaques, however, localization was predominantly found in the medial smooth muscle cells. Regions of enhanced matrix metalloproteinase 2 and matrix metalloproteinase 9 activity co-localized with the transmural distribution of F2 within the plaque.

CONCLUSIONS

These findings suggest that F2 in regions of increased matrix metalloproteinase activity is a potential mechanism for superimposed thrombotic events in morphologically unstable human carotid plaques. The relationship between plasma lipoprotein (a) levels and accumulation of F2 and the potential correlation of F2 to human plaque disruption and thrombosis warrant further study.

Lipoprotein (a) and the risk of ischemic stroke in young women

BACKGROUND AND PURPOSE

lipoprotein (a) (lp (a)) is a lipid-containing particle similar to LDL which has been found in atherosclerotic plaque. The role of lp (a) in ischemic stroke remains controversial, but some studies suggest lp (a) is particularly important as a risk factor for stroke in young adults. We investigated the role of lp (a) as a risk factor for stroke in young women enrolled in the Stroke Prevention in Young Women Study.

METHODS

subjects were participants in a population-based, case-control study of risk factors for ischemic stroke in young women. Cases were derived from surveillance of 59 regional hospitals in the central Maryland, Washington DC, Pennsylvania and Delaware area. Lp (a) was measured in 110 cases and 216 age-matched controls. Demographics, risk factors, and stroke subtype were determined by interview and review of medical records.

RESULTS

lp (a) values were higher in blacks than whites, but within racial groups, the distribution of lp (a) values was similar between cases and controls. After adjustment for age, race, hypertension, diabetes, cigarette smoking, coronary artery disease, total cholesterol and HDL cholesterol, the odds ratio for an association of lp (a) and stroke was 1.36 (95% CI 0.80-2.29). There was no dose-response relationship between lp (a) quintile and stroke risk. Among stroke subtypes, only lacunar stroke patients had significantly elevated lp (a) values compared to controls.

CONCLUSIONS

we found no association of lp (a) with stroke in a population of young women with ischemic stroke. Small numbers of patients limit conclusions regarding risk in ischemic stroke subtypes, but we could not confirm previous suggestions of an association of lp (a) with atherosclerotic stroke in young adults.

Lipoprotein (a), haemostatic variables and cardiovascular damage in hypertensive patients

OBJECTIVE

Lipoproteins and coagulation factors are independent predictors of atherothrombotic events in the general population and their interaction may contribute to the development of cardiovascular damage. This study was designed to assess relationships between lipoproteins, haemostatic variables, and atherosclerotic complications in hypertensive patients.

METHODS

In 389 untreated essential hypertensive patients recruited at a hypertension clinic, we measured plasma lipids, apolipoproteins, lipoprotein (a), apolipoprotein (a) isoforms, fibrinogen, and parameters that directly reflect the coagulation activation. Hypertensive patients were compared to 92 normotensive controls.

RESULTS

Univariate analysis showed log lipoprotein (a) concentrations to be significantly correlated with age (P< 0.02), apolipoprotein B (P< 0.02), plasma fibrinogen (P< 0.001), and fibrin D-dimer (P< 0.001) levels, but not with body mass index, blood pressure, dietary fat intake, cholesterol, triglycerides, apolipoprotein Al, prothrombin fragment 1 + 2, and antithrombin III. The relationship of lipoprotein (a) with fibrinogen and D-dimer was present in both sexes, whereas the relationship of lipoprotein (a) with age and apolipoprotein B was found only in males. Multiple regression analysis showed that both fibrinogen and D-dimer were independently related with lipoprotein (a). Elevated fibrinogen, D-dimer, and lipoprotein (a) levels were significantly and independently associated with clinical evidence of atherosclerotic disease. To investigate whether the relationships of lipoprotein (a) with coagulation parameters are genetically determined, we analysed apolipoprotein (a) phenotypes in a subset of 188 hypertensive patients. While lipoprotein (a) levels were inversely correlated with apolipoprotein (a) isoform protein size, both fibrinogen and D-dimer concentrations were comparable in patients with apolipoprotein (a) isoforms of different size.

CONCLUSIONS

This study demonstrates a relationship between lipoprotein (a) and clotting variables in hypertensive patients that may contribute to atherosclerotic damage in these patients. There is no evidence of a genetic background for this relationship.

Effects of apolipoprotein A gene polymorphisms on lipoprotein (a) concentrations in Japanese

1. Elevated plasma lipoprotein (a) (Lp(a)) concentrations have been correlated with an increased risk of premature cardiovascular disease. The plasma Lp(a) concentration is quantitatively heritable and the apolipoprotein (Apo) A gene is known as a major locus-determining Lp(a) concentration. 2. The aim of the present study was to evaluate the genetic effect of polymorphisms in the 5'-untranslated region (UTR) of the ApoA gene on plasma concentrations of Lp(a). 3. We analysed two sequence variations in the 5'-UTR, a pentanucleotide repeat (PNR) polymorphism and haplotypes composed of three single base substitutions, in 325 Japanese subjects. The ApoA size polymorphism was also analysed by western blotting. 4. The plasma Lp(a) concentration was inversely correlated with the size of the ApoA molecule. Both PNR and the haplotype polymorphisms had significant effects on serum Lp(a) concentrations (P = 0.001 and 0.004, respectively) when the effects were evaluated by ANCOVA using the ApoA size polymorphism as a covariate. 5. When a stratified subpopulation with a larger ApoA size was analysed, both variations influenced or tended to influence the serum Lp(a) concentration, confirming the results of the ANCOVA. 6. Pentanucleotide repeat showed a tight linkage disequilibrium with the haplotypes. This disequilibrium may account for the apparent effects of PNR on Lp(a) concentrations.

Genetics of stroke--a review

Evidence from twin and family shows that genetic factors contribute to the risk of stroke and that their role may be at least as important in stroke as in coronary heart disease. Additional support for the significance of genetic factors comes from other findings such as epidemiological data showing phenotypic heterogeneity of stroke, genetic influence on many of the risk factors for stroke, and racial and geographic differences in morbidity and mortality in stroke victims. Yet, apart from the reported associations of a small number of cases with Mendelian cerebrovascular diseases, only a few studies have directly investigated gene markers or molecular genetics of stroke. This review presents the existing evidence on the genetic background of stroke and discusses results from the genetic studies of stroke published to date.

Tracking of serum lipoprotein (a) concentration and its contribution to serum cholesterol values in children from 7 to 36 months of age in the STRIP Baby Study. Special Turku Coronary Risk Factor Intervention Project for Babies

We investigated the tracking phenomenon of serum lipoprotein (a) concentrations and assessed the impact of serum concentration of lipoprotein (a) cholesterol on total cholesterol concentrations in children from 7 to 36 months of age. Serum samples for lipoprotein (a) and cholesterol determinations at 7, 13, 24 and 36 months were prospectively obtained from 430 children. Serum lipoprotein (a) was determined using immunoradiometric assay. A strong correlation was observed between lipoprotein (a) concentrations at 7 and 36 months of age (r = 0.88, P < 0.001). Seventy-eight per cent to 86% of the children in the lowest and highest lipoprotein (a) quintiles at 13 months remained in the respective quintiles at 36 months. The average contribution of lipoprotein (a) cholesterol to total cholesterol varied from 0.5% to 3.2% (individual variation 0.13-32.39%) depending on the type of milk received and the age of the children. At 7 months the contribution was 0.44% in breast-fed and 0.93% in formula-fed infants (P < 0.0001). The tracking phenomenon of serum lipoprotein (a) concentrations is strong already in early childhood. The contribution of lipoprotein (a) cholesterol to serum total cholesterol concentration should be taken into account when the changes in serum cholesterol levels are interpreted in the first year of life.

Relationship between lipoprotein (a) and both stroke and carotid atheroma

In vitro studies provide mechanisms by which elevated lipoprotein (a) [Lp(a)] concentrations may promote both thrombosis and atherogenesis. Case-control studies have reported raised Lp(a) concentrations in patients with stroke, but prospective studies have failed to confirm the association. A potential confounding factor is that Lp(a) may rise acutely after stroke. We determined Lp(a) concentrations in 164 patients studied at least 21 days after stroke or transient ischaemic attack, and in 91 controls. In the patient group we correlated Lp(a) concentrations with both the degree of carotid stenosis estimated on duplex ultrasonography, and with stroke subtype (large vessel disease, lacunar infarction, and cardioembolic and unknown pathogenesis). There was no difference between Lp(a) concentration in cases and controls [median (quartiles) 0.10 (0.04, 0.39) versus 0.12 (0.04, 0.30) g/L, P = 0.34]. There was no difference in the proportion of cases compared with controls with a markedly elevated Lp(a) of > 0.4 g/L (21.3 versus 16.5%, P = 0.34). There was non-significant trend towards higher median Lp(a) concentrations in women [median (quartiles) 0.16 (0.04, 0.32) g/L versus 0.12 (0.04, 0.28) g/L, P = 0.3]. In view of this trend we analysed the differences between cases and controls for each sex separately. Lp(a) concentrations in men were median (quartiles) 0.08 (0.04, 0.26) g/L in the 101 cases and 0.12 (0.04, 0.28) g/L in the 43 controls (P = 0.6). Lp(a) concentrations in women were median (quartiles) 0.25 (0.04, 0.44) g/L in the 63 cases, and 0.16 (0.04, 0.32) g/L in the 48 controls (P = 0.16). Within the patient group there was no difference between Lp(a) concentrations in the different stroke subgroups. There was no relationship between Lp(a) concentrations and mean percentage carotid stenosis (rs = 0.14, P = 0.07). Our results suggest that in an unselected population of men studied more than 3 weeks post event there is no relationship between lipoprotein(a) concentrations and either stroke/transient ischaemic attack, or carotid atheroma. The relationship in women requires further study.

Lipoprotein(a) in Korean children and a history of coronary or cerebral vascular events in their older family members

The purpose of this study was to determine the relationships between serum apolipoprotein concentration and family history of coronary or cerebral events in schoolchildren. In 269 primary schoolchildren aged 6-11 years (145 boys and 124 girls) we measured the blood concentrations of total cholesterol, apolipoproteins B and A-1, and lipoprotein(a), and questioned their parents about coronary or cerebral vascular events. Serum concentrations of apo B, A-1 and Lp(a) significantly increased with age. In children with serum cholesterol concentration > 5.18 mmol/L the concentrations of apo B, A-1, Lp(a) and apo B/apo A-1 ratio were significantly higher. The concentrations of total cholesterol, apo B, Lp(a), and apo B/apo A-1 ratio in the obese group (body weight 20% above the median body weight for age and height) differed significantly from those in the non-obese group. Serum concentrations of Lp(a) in the children who had positive family histories of coronary or cerebral events (geometric mean = 0.174 x/divided by 0.036g/L) and was significantly higher than that in the children with negative history (geometric mean = 0.086 x/divided by 0.36g/L). Family history was an independent and major contributor to high Lp(a). In evaluating children's lipid profiles, measurement of Lp(a) may help to identify children and their families at increased risk and this may facilitate the targeting of preventive measures.

Plasma lipoprotein(a) distribution in the Framingham Offspring Study as determined with a commercially available immunoturbidimetric assay

The purpose of our research was to evaluate a commercially available, automated, immunoturbidimetric assay for lipoprotein(a) (Lp(a)), to determine the distribution of Lp(a) in the Framingham Offspring Study population, and to determine Lp(a) levels that may be useful for assessing coronary heart disease risk. The mean between-run coefficient of variation for this assay was 5.65%. Lp(a) concentration was slightly, but significantly, higher in 1949 white women (mean +/- S.D. 214 +/- 195 mg/l, median 150 mg/l) than in 1884 white men (mean +/- S.D. 200 +/- 193 mg/l, median 130 mg/l) participating in Cycle 4 of the Framingham Offspring Study (P = 0.0015). Lp(a) values of 300 mg/l and 500 mg/l corresponded to approximately the 75th and 90th percentiles, respectively, for both men and women, and subjects with concentrations greater than or equal to 500 mg/l were more likely to have coronary heart disease than subjects with an Lp(a) concentration less than 300 mg/l (P < 0.05 for men).

Lipoprotein(a) is an independent risk factor for multiple cerebral infarctions

In an attempt to ascertain whether Lp(a) is a risk factor for multiple cerebral infarctions (MCI), we have studied 83 patients with proven MCI and 39 subjects without MCI by computed tomography (CT). Seventy-one patients with non-insulin-dependent diabetes mellitus (NIDDM) were included: 52 with and 19 without MCI. Serum Lp(a) levels were significantly higher in patients with MCI than in subjects without MCI. There were no differences in serum Lp(a) levels between NIDDM and non-diabetic patients with MCI. The logistic regression analysis revealed that Lp(a) and hypertension were independent risk factors for the cerebral event. The current study demonstrated that Lp(a) and hypertension are significant risk factors for multiple cerebral infarctions.

Correlation of toddlers' serum lipoprotein(a) concentration with parental values and grandparents' coronary heart disease: the STRIP baby study

The correlation between lipoprotein(a) (Lp(a)) concentrations in children aged 7-24 months and their family members was determined and the association between the Lp(a) values of the children and a family history of coronary heart disease (CHD) was assessed. The Lp(a) values of the children correlated strongly with midparent Lp(a) values as early as at 7 months of age (r = 0.54 to 0.59, p < 0.0001). This correlation was stronger than the correlation of serum total cholesterol and total cholesterol corrected for Lp(a)-cholesterol between children and parents. None of the parents had CHD. The median Lp(a) concentration of the parents with a family history of CHD was significantly higher than that of parents with no such history (111 vs 87 mg/1, p = 0.024). However, the children's Lp(a) levels were not associated with CHD in their grandparents. The genetic dependence of the Lp(a) concentration is already evident in infancy. The Lp(a) concentration in young parents, but not in their 24-month-old children, is associated with CHD in grandparents. This may be explained by a dilution of the genetic influence on Lp(a) over two generations.