Ethnic trends in lipid tests in general practice

The impact of multiple blood donations on the risk of cardiovascular diseases: Insight of lipid profile

OBJECTIVES

The reduction in blood viscosity and iron store were proposed to be connected to the reduction in the risk of cardiovascular disease (CVD) among multiple blood donors. Herein, we evaluated the modulation of serum lipids levels in accordance with donation events. Furthermore, atherogenic impacts on the risk of CVD were investigated.

MATERIALS AND METHODS

A total of 100 voluntarily male donors were included in the study. Fifty donors were multiple time donors (MTD) and 50 were single time donors (STD). Levels of serum lipids were determined and atherogenic indices including TG/HDL and CHO/HDL ratios were calculated. QRISK2 parameters were determined to evaluate the 10-years risk of developing CVD.

RESULTS

Among MTD, there were significantly higher serum levels of triglycerides (TG) and very low-density lipoproteins (VLDL) combined with significantly lower HDL level. These modulations were significantly correlated to the extent of donation. Both CHO/HDL and TG/HDL ratios were also significantly higher among MTD. However, only TG/HDL ratio was strongly correlated to the donation extent even when controlled for age, BMI and smoking status. Despite the significant difference in QRISK2 parameters between study groups, none of these parameters was correlated to the extent of donation when controlling for age, BMI and smoking status.

CONCLUSION

We demonstrate that multiple blood donation is associated with an unfavorable modulation of serum levels of lipids that is influenced by donation extent. This modulation is not associated with an increased risk of CVD but may weakly contribute in a higher risk for coronary heart disease (CHD).

Association of anthropometric measures with cardiovascular risk factors and metabolic syndrome in normal-weight children and adolescents: the CASPIAN III study

OBJECTIVE

This nationwide study was conducted to determine the association of anthropometric measures with cardiovascular risk factors and metabolic syndrome (MetS) in Iranian normal-weight children and adolescents.

METHODS

We analyzed the data of 3,565 children and adolescents (50.3% boys), aged 10-18 years, with a normal BMI (5th-84th percentile) obtained from the third survey of 'Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Disease' (CASPIAN III) study. The diagnostic criteria for MetS were defined by the International Diabetes Federation consensus.

RESULTS

The prevalence of MetS for 10- to 13.9-year-old boys, 14- to 18-year-old boys, 10- to 13.9-year-old girls, and 14- to 18-year-old girls were 1.4, 2.8, 2.3, and 3.3%, respectively. After adjustment for age and sex, each unit increase in BMI (within normal range) and waist circumference increased the odds of MetS from 6 to 72% and from 1 to 20%, respectively. The dominant pattern of dyslipidemia among the participants was high triglycerides and low high-density lipoprotein cholesterol.

CONCLUSION

This study complements recent research about the high frequency of metabolic risk factors among normal-weight individuals in the pediatric age group.

Prevalence of dyslipidemia and goal attainment after initiating lipid-modifying therapy: a Thai multicenter study

Previous studies focused on attaining low-density lipoprotein cholesterol (LDL-C) goals after lipid-modifying therapy (LMT), but data on achieving normal levels of triglyceride and high-density lipoprotein cholesterol (HDL-C) are limited. We reviewed medical records of patients initiated on LMT. High risk was defined as patients with coronary heart disease, diabetes, or 10-year Framingham risk >20%. Among 806 patients enrolled, 429 were at high risk. Prior to initiation of LMT, 66%, 35%, and 44% overall and 69%, 35%, and 45% in the high-risk group had elevated LDL-C, elevated triglyceride, and low HDL-C, respectively. After 12 months of LMT, 21%, 32%, and 39% overall and 26%, 25%, and 43% in the high-risk group still had elevated LDL-C, elevated triglyceride, and low HDL-C, respectively. Approximately 1 of 5 patients continued to experience elevated LDL-C coupled with elevated triglyceride and/or low HDL-C. In conclusion, a substantial proportion of patients initiated on LMT continued to have lipid abnormalities.

Distinct ethnic differences in lipid profiles across glucose categories

CONTEXT

Dyslipidemia coexists with hyperglycemia. However, little is known about the ethnic differences in lipid profiles at comparable glucose tolerance status.

OBJECTIVE

The aim was to study ethnic differences in lipid profiles stratified by glucose levels.

DESIGN AND SETTING

Data from 31 study cohorts of 12 countries, consisting of 24,760 men and 27,595 women aged 25-74 yr, were compared. The odds ratio for having dyslipidemia was estimated for each ethnic group stratified by glucose categories.

RESULTS

Compared with central and northern Europeans, multivariable adjusted odds ratios (95% confidence intervals) for having lower high-density lipoprotein-cholesterol were 4.74 (4.19-5.37), 5.05 (3.88-6.56), 3.07 (2.15-4.40), and 2.37 (1.67-3.35) in Asian Indian men, but 0.12 (0.09-0.16), 0.07 (0.04-0.13), 0.11 (0.07-0.20), and 0.16 (0.08-0.32) in Chinese men who had normoglycemia, prediabetes, and undiagnosed and diagnosed diabetes, respectively. Similar results were obtained for women. The prevalence of low high-density lipoprotein-cholesterol remained higher in Asian Indians (62.8% of the nondiabetic and 67.4% of the diabetic) than in central and northern Europeans (20.3 and 37.3%), Japanese (25.7 and 34.1%), or Qingdao Chinese (15.7 and 17.0%), even in individuals with low-density lipoprotein-cholesterol of less than 3 mmol/liter.

CONCLUSION

There are distinct patterns of lipid profiles associated with ethnicity regardless of the glucose levels, suggesting that ethnic-specific strategies and guidelines on risk assessment and prevention of cardiovascular disease are required.

Admixture mapping of quantitative trait loci for blood lipids in African-Americans

Blood lipid levels, including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG), are highly heritable traits and major risk factors for atherosclerotic cardiovascular disease (CVD). Using individual ancestry estimates at marker locations across the genome, we present a novel quantitative admixture mapping analysis of all three lipid traits in a large sample of African-Americans from the Family Blood Pressure Program. Regression analysis was performed with both total and marker-location-specific European ancestry as explanatory variables, along with demographic covariates. Robust permutation analysis was used to assess statistical significance. Overall European ancestry was significantly correlated with HDL-C (negatively) and TG (positively), but not with LDL-C. We found strong evidence for a novel locus underlying HDL-C on chromosome 8q, which correlated negatively with European ancestry (P = .0014); the same location also showed positive correlation of European ancestry with TG levels. A region on chromosome 14q also showed significant negative correlation between HDL-C levels and European ancestry. On chromosome 15q, a suggestive negative correlation of European ancestry with TG and positive correlation with HDL-C was observed. Results with LDL-C were less significant overall. We also found significant evidence for genome-wide ancestry effects underlying the joint distribution of HDL-C and TG, not fully explained by the locus on chromosome 8. Our results are consistent with a genetic contribution to and may explain the healthier HDL-C and TG profiles found in Blacks versus Whites. The identified regions provide locations for follow-up studies of genetic variants underlying lipid variation in African-Americans and possibly other populations.

Lipid testing among patients beginning statin therapy in general practice in the United Kingdom

OBJECTIVES

To determine the frequency of lipid testing and to identify the factors predictive of lipid-testing frequency over a 1-year period in patients beginning statin treatment.

METHODS

Retrospective cohort study performed using the UK General Practice Research Database. The patients were selected if they were > or = 35 years of age, received first-ever statin between January 2000 and December 2004, had at least one total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), or triglyceride (TG) test conducted in the 1-year period before statin initiation, and had at least 1 year of follow-up data. The main outcome measures were TC, HDL-C, and TG testing frequencies in the year after initiating statins. Poisson regression was used to assess baseline factors associated with testing frequency for each lipid.

RESULTS

In the year after initiating statins, the patients received a mean (+/-SD) of 1.3 (+/-1.0) TC tests, 0.9 (+/-1.0) HDL-C tests, and 0.9 (+/-1.0) TG tests; however, 22.7%, 44.3%, and 39.1% of the patients did not receive any TC, HDL-C, and TG tests, respectively. In multivariate analyses, a high coronary heart disease (CHD) risk (odds ratio [OR] 1.04; 95% confidence interval [CI] 1.01-1.07) and elevated baseline TC (> or = 6.2 vs. < 5.0 mmol/L; OR 1.12; 95% CI 1.06-1.18) were significantly associated with greater TC testing frequency.

CONCLUSIONS

High risk of CHD and elevated baseline TC were associated with greater rates of TC testing in the year after statin initiation. Lack of TC testing in approximately one in five patients, and infrequent HDL-C and TG testing may be barriers to comprehensive lipid management.

Patients' acceptance of antihypertensive therapy to prevent cardiovascular disease: a comparison between South Asians and Caucasians in the United Kingdom

BACKGROUND

The importance of patients' involvement in decision-making is because of their right to know the risks and benefits they accept in undertaking treatment and the as yet unproven hope that this will improve compliance. The aim of this study was to establish local people's willingness to receive antihypertensive treatment for primary prevention of cardiovascular disease (CVD) and to explore the role of ethnicity.

METHODS

In a cross-sectional study with face-to-face interview South Asian and Caucasian men and women aged 35-74, with and without history of CVD, were interviewed. Minimal clinically important differences were measured for three different baseline CVD risks (10, 20, and 40% in 10 years) using a standard method with risks presented both graphically and numerically and expressed in positive and negative terms.

RESULTS

A total of 262 (110 South Asians) participants were interviewed. Overall, South Asians expressed smaller median minimal clinically important differences than Caucasians, 1 and 4%, respectively. Up to 17% of participants in both ethnic groups indicated that they would not take medication regardless of the benefits. The proportion of South Asian men unwilling to take medication regardless of benefit was higher than Caucasian men for all scenarios, 17.2 versus 10.7% for scenario 1 and 12.1 versus 5.6% for scenario 2, respectively. South Asians of both sexes who would consider therapy required less benefit for acceptance in all three scenarios compared with the Caucasians.

CONCLUSION

South Asian participants were at least likely as Caucasians to accept antihypertensive treatment as the primary prevention therapy and they should be targeted for this type of therapy.

Simultaneous genotyping of the three lactose tolerance-linked polymorphisms LCT -13907C>G, LCT -13910C>T and LCT -13915T>G with Pyrosequencing technology

BACKGROUND

We required a new genotyping method for the diagnosis of adult hypolactasia, which would allow the simultaneous genotyping of three known polymorphic loci linked to lactose tolerance (LCT -13907C>G, LCT -13910C>T and LCT -13915T>G) in a single PCR/pyrosequencing test run.

METHOD

We utilized Pyrosequencing technology, a DNA-sequence-by-synthesis technique.

RESULTS

The developed Pyrosequencing method allowed genotyping of the three loci LCT -13907C>G, LCT -13910C>T and LCT -13915T>G in a single PCR/pyrosequencing test run. A separate Pyrosequencing assay was developed for genotyping of the LCT -14010G>C mutation. The methods were evaluated in 116 clinical samples from patients of non-European descent, sent to the laboratory for diagnosis of adult hypolactasia. The "African" mutations LCT -13907C>G and LCT -13915T>G were found in subjects originating not only from Somalia, Ethiopia and Eritrea but also in Arabs and Iranians. Several compound heterozygotes LCT -13907CG/-13915TG were found among Ethiopian, Eritrean and Somalian subjects. No subject with the LCT -14010G>C mutation was found among the studied subjects. Advantages compared to the other genotyping methods are less staff hands-on time than, e.g., restriction fragment length polymorphism (RFLP) analyses, avoiding radioactivity as in the originally described isotope-minisequencing and in addition, Pyrosequencing is a direct DNA sequencing technique which gives unambiguous genotyping results as well as some redundant sequence information beyond the single nucleotide polymorphism (SNP) position, which serves as a valuable internal control obtained for each sample.

CONCLUSIONS

Pyrosequencing is a robust genotyping modality suitable for clinical genotyping of patients not only of European, but also of African or Middle Eastern descent, who may harbor any combination of the three LCT mutations, LCT -13907C>G, LCT -13910C>T, LCT -13915T>G.

Prevalence and trends in adult-type hypolactasia in different age cohorts in Central Sweden diagnosed by genotyping for the adult-type hypolactasia-linked LCT -13910C > T mutation

OBJECTIVE

Adult-type hypolactasia (AtH) can be diagnosed by genotyping in addition to functional tests or intestinal biopsy. The aims of this study were to estimate the prevalence of AtH by genotyping and to investigate whether AtH prevalence has changed in Sweden during the 20th century.

MATERIAL AND METHODS

Schoolchildren (n=690) born in 1983 and 1989, and elderly individuals (n=392) born between 1920 and 1932 were genotyped for AtH using Pyrosequencing technology.

RESULTS

The overall prevalence of AtH among children was 14.1%. The majority of children (92%, n=635) were Caucasians with genotype prevalences: CC, 61 (10%); CT, 259 (41%); TT, 307 (49%). The frequency of the mutated allele q was 0.300 in this cohort. The prevalence of AtH estimated from the Hardy-Weinberg equilibrium (HWE) (q 2), was 9.0% (95% CI: 6.7-11.2%). Eight percent (n=55) of the children were non-Caucasian; genotype prevalences were CC, 36 (66%); CT, 15 (27%); TT, 4 (7%). The prevalence of AtH in these children estimated from HWE was 62.5% (95% CI: 49.7-75.3%). The elderly subjects were all Caucasians. Their genotype prevalences were: CC, 20 (5%); CT, 166 (42%); TT, 206 (53%); the frequency of the mutated allele q was 0.262 and their AtH prevalence estimated from HWE was 6.8% (95% CI: 4.3-9.2%).

CONCLUSIONS

The overall prevalence of AtH in children (14%) was higher than previously thought. Among Caucasians, higher figures were seen in children than in the elderly (9% versus 6.8%). The prevalence thus seems to be increasing and this may be due to the immigration of both non-Caucasian and Caucasian groups with a higher prevalence of AtH.

Comparative levels and time trends in blood pressure, total cholesterol, body mass index and smoking among Caucasian and South-Asian participants of a UK primary-care based cardiovascular risk factor screening programme

Background

Individuals of South-Asian origin have a comparatively higher cardiovascular disease burden, but there is uncertainty about whether this is due to differences in risk factor levels and trends. We therefore studied comparative levels and time trends in blood pressure (BP), total cholesterol, body mass index (BMI) and current smoking among UK Caucasian and South-Asian individuals.

Methods

Repeatable cross-sectional survey of men and women aged 35–60 attending for first screening as part of a primary-care based cardiovascular risk factor screening programme 1989 and 1999.

Results

Of 34,122 men and 37,294 women participants, 499 men (1.5%)and 381 women (1%) were of South-Asian origin. South-Asian men had lower systolic [(-4.91 mmHg (95% Confidence Iterval (CI): -3.58 to -6.23)] and diastolic BP [-2.87 mmHg (-2.02 to -3.72)], with no significant differences in cholesterol and BMI. South-Asian women had lower systolic BP [-1.77 mmHg, 95% (-0.21 to -3.33)], diastolic BP [-1.87 mmHg (-0.92 to -2.82)], cholesterol [-0.24 mmol/l (-0.08 to -0.39)]; and higher BMI [+0.78 kg/m² (0.25 to 1.3)]. South-Asian men and women had significantly lower prevalence of self-reported current smoking (29.0% and 1.8% respectively). With the exception of self-reported current smoking, between ethnic group risk factor trends were not converging.

Conclusion

With the exception of women's BMI, South-Asian individuals had either lower or similar levels of the examined cardiovascular risk factors, compared with Caucasian individuals. Although time trends in smoking were converging, other risk factors trends were similar between the two ethnic groups. Overall the findings do not support the hypothesis that the relatively high cardiovascular disease burden in UK South-Asians is due to higher levels exposure to the examined risk factors. Other hypotheses, such as higher frequency of diabetes and increased genetic predisposition, require further exploration.

Comparative levels and time trends in blood pressure, total cholesterol, body mass index and smoking among Caucasian and South-Asian participants of a UK primary-care based cardiovascular risk factor screening programme

Background

In the UK, obesity is associated with a clear socioeconomic gradient, with individuals of lower socioeconomic status being more likely to be obese. Several previous studies, using individual measures of soecioeconomic status, have shown a more rapid increase in Body Mass Index (BMI) over time among adults of lower socioeconomic status. We conducted a study to further examine whether ecologically defined deprivation status influences within-individual BMI change during middle life, as the answer to this question can help determine optimal preventive strategies both for obesity per se, and its' associated socioeconomic disparities.

Methods

Anonymised records of participants to the Stockport population-based cardiovascular disease risk factor screening programme were analysed. Individuals aged 35–55 who had a first screening episode between 1989 and 1993, and a subsequent screening episode were included in the study. Deprivation status was defined using quintiles of the Townsend score. Mean annual BMI change by deprivation group was calculated using linear regression. Subsequently, deprivation group was included in the model as an ordinal variable, to test for trend. The modelling was repeated separately for individuals who were obese (BMI < 30) and non-obese at the time of first screening. In supplementary analysis, regression models were also adjusted for baseline BMI.

Results

Of 21,976 women and 19,158 men initially screened, final analysis included just over half of all individuals [11,158 (50.8%) women and 9,831 (51.3%) men], due to the combined effect of loss to follow-up and incomplete BMI ascertainment. In both sexes BMI increased by 0.19 kg/m² annually (95% Confidence Intervals 0.15–0.24 for women and 0.16–0.23 for men). All deprivation groups had similar mean annual change, and there was no evidence of a significant deprivation trend (p = 0.801, women and 0.892, men). Restricting the analysis to individuals who were non-obese at baseline did not alter the results in relation to the lack of a deprivation effect. When restricting the analysis to individuals who were obese at baseline however, the findings were suggestive of an association of BMI increase with higher deprivation group, which was further supported by a significant association when adjusting for baseline BMI.

Conclusion

In the study setting, the BMI of non-obese individuals aged 35–55 was increasing over time independently of deprivation status; among obese individuals a positive association with higher deprivation was found. The findings support that socioeconomic differences in mean BMI and obesity status are principally attained prior to 35 years of age. Efforts to tackle inequalities in mean BMI and obesity status should principally concentrate in earlier life periods, although there may still be scope for focusing inequality reduction efforts on obese individuals even in middle life.

Comparison of processes and intermediate outcomes between South Asian and European patients with diabetes in Blackburn, north-west England

BACKGROUND

Diabetes and its complications are more prevalent among South Asians than people of European origin and there is some evidence that patients of South Asian origin with diabetes receive poorer quality care.

METHODS

Longitudinal study of patients with diabetes in Blackburn, UK. Processes of care indicators [measurement of blood pressure (BP), cholesterol and glycosolated haemoglobin (HbA1c)] and values of these intermediate outcomes were extracted for all patients registered on a diabetes information system for the period 1995-2001. Differences in processes of care indicators and intermediate outcomes between ethnic groups were estimated after adjusting for the potential confounding factors of sex, age and socioeconomic status (SES). Generalized estimating equations were used to model trends and to test for differences in trends over time.

RESULTS

Process of care was similar in South Asian and European patients. Mean BP and cholesterol concentration fell during the study period. South Asians had a higher level of HbA1c throughout the study period. South Asians had lower levels of BP and cholesterol in 1995 but the differences diminished or were abolished over time. SES did not explain differences between ethnic groups. Analyses stratified by baseline levels of intermediate outcomes (above or within target) demonstrated improvements among above target patients were greater among European patients.

CONCLUSIONS

Processes of care indicators are similar in diabetic patients of South Asian and European origin, irrespective of SES. However, there are worrying differences in improvements over time in the intermediate outcomes, and glycaemic control remained poorer among patients of South Asian origin patients throughout.