History of cardiovascular disease and cardiovascular biomarkers are associated with 30-day mortality in patients with hip fracture.

Hip fractures are associated with increased mortality and it is important to identify risk factors. This study demonstrates that preexisting cardiovascular disease as well as cardiovascular biomarkers that are associated with increased 30-day mortality. These findings can be used to identify high-risk patients who might benefit from specialized care. INTRODUCTION: This study investigates the association between cardiovascular disease (CVD), cardiovascular biomarkers, and 30-day mortality following a hip fracture. METHODS: The Danish National Patient Registry was used to investigate the association between CVD and mortality following hip fracture in a nationwide population-based cohort study. In a subset of the included patients (n = 355), blood samples were available from a local biobank. These samples were used for analyzing the association between specific biochemical markers and mortality. The primary outcome was 30-day mortality. RESULTS: A total of 113,211 patients were included in the population-based cohort study. Among these, heart failure was present in 9.4%, ischemic heart disease in 15.9%, and ischemic stroke in 12.0%. Within 30 days after the hip fracture, 11,488 patients died, resulting in an overall 30-day mortality of 10.1%. The 30-day mortality was significantly increased in individuals with preexisting CVD with multivariably adjusted odds ratios of 1.69 (95% confidence interval, 1.60-1.78) for heart failure, 1.23 (1.17-1.29) for ischemic heart disease, and 1.06 (1.00-1.12) for ischemic stroke. In the local database including 355 patients, 41 (11.5%) died within 30 days. The multivariably adjusted odds ratio for 30-day mortality increased with increasing NT-proBNP (2.36 [1.53-3.64] per quartile) and decreased with increasing HDL cholesterol (0.58 [0.41-0.82] per quartile). On this basis, we established a model for predicting the probability of death based on the biochemical markers. CONCLUSION: Preexisting CVD was associated with increased 30-day mortality after a hip fracture. Furthermore, high levels of NT-proBNP and low levels of HDL cholesterol were associated with increased 30-day mortality.

A longitudinal study of the effect of GSTT1 and GSTM1 gene copy number on survival.

Deletions of the glutathione S-transferase superfamily genes GSTT1 and GSTM1 has been associated with oxidative stress related diseases and recently explored as factors implicated in longevity as well. Reported results have been conflicting, which may partially be caused by the traditional use of assays unable to discriminate between carriers of one or two functional genes. Using a quantitative realtime PCR method facilitating quantification of gene copy number, we evaluated the influence of GSTT1 and GSTM1 gene deletions on longevity in a longitudinal study of 681 elderly Danish twins. The mean follow-up time was 7.6 years and during this time a total of 294 deaths occurred. The results demonstrated a non-significant trend for carriage of two copies of the GSTM1 functional gene to be a protective factor, whereas both heterozygosity and homozygosity for the GSTT1 functional gene was associated with a moderate but significant increased mortality in women (hazard rate 2.46 (CI95: 1.43-4.23) and 2.22 (CI95: 1.25-3.94) for one and two alleles, respectively). To our knowledge, this is the first longitudinal study exploring the influence of GST gene polymorphisms on longevity and these data implies that GST gene copy numbers do affect mortality risk in the elderly.

Genetic influence on thrombotic risk markers in the elderly--a Danish twin study.

OBJECTIVE: Several hemostatic variables are identified as cardiovascular risk markers. In young and middle-aged individuals, plasma concentrations of these variables are partly determined by genetic factors. The genetic contribution to cardiovascular disease (CVD) decreases with increasing age, and it is therefore important to determine the heritability of hemostasis also in the elderly. METHODS: The heritability of plasma levels of factor VII, fibrinogen, tissue factor, tissue factor pathway inhibitor, von Willebrand factor, thrombin activatable fibrinolysis inhibitor (TAFI), and D-dimer was determined in 130 monozygotic and 155 dizygotic same-sex twin pairs, aged 73-94 years, who participated in the Longitudinal Study of Aging of Danish Twins. Furthermore, we determined the influence of promoter polymorphisms in corresponding genes on the plasma level variation. RESULTS: Genetic factors accounted for 33% (D-dimer) to 71% (TAFI) of the variation in plasma levels. Polymorphisms were associated with concentrations of FVII and TAFI in sib-pair based analyses, but in linkage analyses the polymorphisms did not explain a significant part of the genetic variation for any of the variables. CONCLUSIONS: Concentrations of hemostatic variables have a substantial genetic variation in the elderly, but in this study the promoter polymorphisms only explained a minimal part of this variation.

Platelet count is associated with cardiovascular disease, cancer and mortality: A population-based cohort study.

INTRODUCTION: Platelet count is used to determine bleeding risk and monitoring thrombopoiesis. While abnormal platelet counts are associated with mortality and morbidity, it is unclear whether it also apply to platelet counts within reference range. We investigated the relationship between platelet count (100-450×109/L) and mortality, development of future cardiovascular disease (myocardial infarction, ischaemic stroke, or peripheral vascular disease), venous thromboembolism, bleeding or cancer in the general population. MATERIAL AND METHODS: We conducted a register-based cohort study of 21,252 adults (≥20years) from the Danish General Suburban Population Study (GESUS). Laboratory results from GESUS were linked to information from national registers regarding morbidity and death. Cox proportional hazard regression was conducted with adjustment for age, sex, smoking status, haemoglobin, leukocyte count, C-reactive protein and Charlson comorbidity index. RESULTS: We found a U-shaped relationship between mortality and platelet count. Mortality was significantly increased for platelet count <175×109/L or >300×109/L. When categorizing platelet count using the interval 201-250×109/L as reference group, platelet count 301-450×109/L was associated with mortality, adjusted hazard ratio (HR)=1.42(95% CI 1.06-1.90) and cardiovascular disease, adjusted HR=1.32 (95% CI 1.03-1.69). Platelet count 100-200×109/L was associated with future cancer, adjusted HR=1.28(95% CI 1.05-1.57), but not with future bleeding or venous thromboembolism. CONCLUSIONS: Platelet count is associated with mortality, future cardiovascular disease, and future cancer.

Association of mutations in the hemochromatosis gene with shorter life expectancy.

BACKGROUND: To investigate whether the frequency of carriers of mutations in the HFE gene associated with hereditary hemochromatosis diminishes with age as an indication that HFE mutations are associated with increased mortality. It is of value in the debate concerning screening for hereditary hemochromatosis to determine the significance of heterozygosity. METHODS: Genotyping for mutations in exons 2 and 4 of the HFE gene using denaturing gradient gel electrophoresis in 1784 participants aged 45 to 100 years from 4 population-based studies: all 183 centenarians from the Danish Centenarian Study, 601 people aged 92 to 93 years from the Danish 1905 Cohort, 400 aged 70 to 94 years from the Longitudinal Study of Aging Danish Twins, and 600 aged 45 to 67 years from a study of middle-aged Danish twins. RESULTS: All participants (N=1784) were screened for mutations in exon 4, and a trend toward fewer heterozygotes for the C282Y mutation-the mutation most often associated with hereditary hemochromatosis-was found. This was significant for the whole population (P=.005) and for women (P=.004) but not for men (P=.26). A group of 599 participants was screened for mutations in exon 2, and there was no variation in the distribution of mutations in exon 2 in the different age groups. CONCLUSIONS: In a high-carrier frequency population like Denmark, mutations in HFE show an age-related reduction in the frequency of heterozygotes for C282Y, which suggests that carrier status is associated with shorter life expectancy.

Ultrarapid metabolism of sparteine: frequency of alleles with duplicated CYP2D6 genes in a Danish population as determined by restriction fragment length polymorphism and long polymerase chain reaction.

CYP2D6 is a polymorphically expressed enzyme with two phenotypes. Poor metabolizers lack the enzyme caused by inactivating mutations in the CYP2D6 gene and extensive metabolizers have at least one active CYP2D6 gene. Extensive metabolizers with very high capacity for CYP2D6 dependent drug metabolisms are termed ultrarapid metabolizers and carry alleles with duplicated, multi duplicated or amplified CYP2D6 genes. In the present study, we examined the frequency of CYP2D6 gene duplications in a Danish population and validated a long polymerase chain reaction method for identification of ultrarapid metabolizers. Sixty individuals having a metabolic ratio for sparteine at or below 0.15 were selected and a control group of 53 individuals with a metabolic ratio between 0.16 and 12.4 was used. Based on EcoRI restriction fragment length polymorphism analysis, eight individuals were found with a duplicated CYP2D6 gene, whereas using a long polymerase chain reaction method, nine individuals with a 3.6 kb fragment indicative of two CYP2D6 genes in tandem were found among the 60 individuals with a low metabolic ratio. No gene duplication was found in the control group or in any individuals with a metabolic ratio > 0.14. Based on these results, we estimate the frequency of individuals with CYP2D6 duplication in the Danish population to be 0.8%, which is comparable to the frequency in the Swedish and the German populations, but considerably lower than in Spanish or African populations. We conclude that the long polymerase chain reaction assay is simple and reliable for detection of duplications of the CYP2D6 gene.

Paraoxonase 1 polymorphisms and survival.

The antioxidant enzyme paraoxonase 1 (PON1) has previously been suggested to confer protection against coronary heart disease (CHD), one of the main causes of death in the Western world. Two coding polymorphisms, 55M/L and 192Q/R, and a promoter variant, -107C/T, has been extensively studied with respect to susceptibility to CHD. In this study, we have investigated the impact of these three polymorphisms on mortality using a sample of 1932 Danish individuals aged 47-93 years, previously used in gene-longevity studies. A cross-sectional study comparing the genotype distribution of the three polymorphisms separately as well as the haplotype distribution in different age groups did not reveal any difference. However, a longitudinal follow-up study on survival in the same sample indicated that 192RR homozygotes have a poorer survival compared to QQ homozygotes (hazard rate: 1.38, P = 0.04). We hereafter used an independent sample of 541 Danish individuals from the oldest cohort and confirmed the initial findings (hazard rate: 1.38, P = 0.09). In both samples, the effect was most pronounced in women. Using self-reported data on ischemic heart disease to evaluate the impact of the PON 192Q/R polymorphism on susceptibility to CHD, we found only a nonsignificant trend of 192RR homozygosity in women being a risk factor. Our results thus indicates that PON1 192RR homozygosity is associated with increased mortality in women in the second half of life and that this increased mortality is possibly related to CHD severity and survival after CHD rather than susceptibility to development of CHD.

Metabolic gene polymorphism frequencies in control populations.

Using the International Project on Genetic Susceptibility to Environmental Carcinogens (GSEC) database containing information on over 15,000 control (noncancer) subjects, the allele and genotype frequencies for many of the more commonly studied metabolic genes (CYP1A1, CYP2E1, CYP2D6, GSTM1, GSTT1, NAT2, GSTP, and EPHX) in the human population were determined. Major and significant differences in these frequencies were observed between Caucasians (n = 12,525), Asians (n = 2,136), and Africans and African Americans (n = 996), and some, but much less, heterogeneity was observed within Caucasian populations from different countries. No differences in allele frequencies were seen by age, sex, or type of controls (hospital patients versus population controls). No examples of linkage disequilibrium between the different loci were detected based on comparison of observed and expected frequencies for combinations of specific alleles.

Modest implication of interleukin-6 promoter polymorphisms in longevity.

The multifunctional interleukin-6 has been suggested to contribute to a chronic low-grade inflammatory status, thereby conferring susceptibility to age-related pathological conditions as well as functional decline and increased mortality. Several polymorphisms have been identified in the interleukin-6 promoter, but investigation of the effect of these on interleukin-6 levels and disease susceptibility have led to contradictory results. This study investigates the significance of the three single-point polymorphisms (-597G/A, -572G/C and -174G/C) and the AT-stretch polymorphism (-373(A)n(T)m) in ageing, by comparison of the frequency of each single polymorphism separately as well as the entire promoter haplotype in a total of 1710 Danish subjects ranging in age from 47 to 100 years. We found a modest, but significant, increase in the frequency of interleukin-6 -174GG homozygotes with age suggesting that this genotype is advantageous for longevity.

The Danish 1905 cohort: a genetic-epidemiological nationwide survey.

OBJECTIVES: The authors studied nonagenarians, a rapidly growing age group whose cognitive and physical abilities have yet to be investigated systematically. METHODS: All Danes born in 1905 were invited to participate in a home-based 2-hour multidimensional interview, including cognitive and physical performance tests and collection of DNA, carried out by lay interviewers. Population-based registers were used to evaluate representativeness. RESULTS: There were 2,262 participants. A total of 1,632 (72%) gave a DNA sample. Participants and nonparticipants were highly comparable with regard to marital status, institutionalization, and hospitalization patterns, but men and rural area residents were more likely to participate. Six months after the survey began, 7.2% of the participants and 11.8% of the nonparticipants had died. DISCUSSION: Despite the known difficulties of conducting surveys among the extremely old, it was possible to conduct a nationwide survey, including collection of DNA, among more than 2,000 fairly nonselected nonagenarians using lay interviewers.

[Carbohydrate deficient transferrin--a reliable marker of alcohol abuse?]. / Carbohydratdeficiant transferrin--en plidelig alkoholmarkør?

Carbohydrate deficient transferrin (CDT) is an isoform of transferrin with a reduced carbohydrate content, especially the negatively charged sialic acid. This alters the pI value and allows the separation of CDT from normal transferrin. CDT has a higher sensitivity and specificity than other currently known markers of alcoholism. Increased CDT values are found in patients with non-alcoholic liver disease. The cost of the analysis is high and the benefit of this marker is still uncertain.

[Percutaneous endoscopic gastrostomy]. / Perkutan endoskopisk gastrostomi.

Tube feeding is commonly used in providing enteral nutrition to the patient with dysphagia. The percutaneous endoscopic gastrostomy (PEG) is an alternative to the nasogastric tube (NG) and the surgical gastrostomy. The advantages of PEG are short procedure time, the avoidance of using an operating theatre and general anaesthesia and reduced cost. The main indication for PEG is dysphagia due to neurological disease and cancer in the pharynx and oesophagus. A gastrostomy is cosmetically more acceptable than NG, self extubation is more difficult for the confused patient, tube diameter is larger and therefore the tube is not so easily blocked. The patient with a gastrostomy tube is more mobile and is able to start oral nutrition at the same time as receiving enteral nutrition through the gastrostomy tube.

Anti-inflammatory heat shock protein 70 genes are positively associated with human survival.

A positive relationship between stress tolerance and longevity has been observed in several model systems. That the same correlation is applicable in humans and that it may be open to experimental manipulation for extending human lifespan requires studies on association of stress genes with longevity. The involvement of heat shock protein 70 (Hsp70) in cellular maintenance and repair mechanisms, including its role as an anti-inflammatory protein, makes it a suitable candidate for studying such associations. We have studied the association of three single nucleotide polymorphisms, HSPA1A (-110A>C), HSPA1B (1267A>G), and HSPA1L (2437T>C), present in the three HSP70 genes, with human survival, in a cohort of individuals born in the year 1905. This population cohort is a part of the longitudinal study of Danish nonagenarians. Since DNA samples were already collected in 1998, this gave us the opportunity to perform survival analysis on these subjects. Haplotype relative risk, and genotype relative risk were calculated to measure the effects of haplotypes and genotypes on human survival in a sex-specific manner. A significant association of HSPA1A-AA (RR=3.864; p=0.016) and HSPA1B-AA (RR=2.764; p=0.039) genotypes with poor survival was observed in female subjects. Also the female carriers of haplotype G-C-T had longer survival than the non-carriers (HRR=0.550; p=0.015). On an average, female carriers of the G-C-T haplotype live about one year longer than non-carriers. This result corroborates our previous observations from heat shock response (HSR) study where we had shown that after heat stimulation, mononuclear cells from the carriers of genotype HSPA1L-TT had better HSR than cells with the HSPA1L-CC genotype.

Polymorphisms in the low-density lipoprotein receptor-related protein 5 (LRP5) gene are associated with peak bone mass in non-sedentary men: results from the Odense androgen study.

PURPOSE: To investigate the impact of the Ala1330Val (rs3736228, exon 18) and Val667Met (rs4988321, exon 9) polymorphisms of the low-density lipoprotein receptor-related protein 5 (LRP5) gene on peak bone mass in young men. METHODS: The Odense Androgen Study (OAS) is a population-based study comprising 783 Caucasian men aged 20-30 years. Genotyping was performed using real-time polymerase chain reaction (PCR) or fluorescence polarization. Bone mineral density (BMD) measurements were performed using dual-energy X-ray absorptiometry. RESULTS: The CC, CT, and TT genotypes in Ala1330Val were found in 75.6%, 21.8%, and 2.6% of the participants, respectively. Similarly, the GG, GA, and AA genotypes of Val667Met were found in 89.7%, 9.8%, and 0.5%, respectively. For the Ala1330Val polymorphism, no significant differences between the genotypes were found regarding BMD in the overall study population. However, when analysis was restricted to non-sedentary men (n = 589), a significant association between the number of T-alleles and BMD in the spine and whole body were found. Each copy of the T-allele changed the Z-score of the spine by (median and 95% confidence interval) -0.21 [95% CI: -0.40; -0.03] (p < 0.02). Analysis suggested an association between the AA genotype in the Val667Met polymorphism and increased body height and decreased BMD of the femoral neck; however, no significant gene-dose effect of the A-allele could be demonstrated in the whole population. When the analysis was restricted to non-sedentary subjects, however, each number of A-alleles was associated with a change in Z-score of -0.26 [95% CI: -0.51; -0.01] (p = 0.04). No further significant results emerged with haplotype analysis. CONCLUSION: The Ala1330Val and Val667Met polymorphisms in the LRP5 gene are significantly associated with peak bone mass in physically active men.

Energy expenditure, body composition and insulin response to glucose in male twins discordant for the Trp64Arg polymorphism of the beta3-adrenergic receptor gene.

AIM: The tryptophan to arginine change in position 64 (Trp64Arg) polymorphism of the beta3-adrenergic receptor (beta3AR) gene has been associated with an increased prevalence of obesity, insulin resistance and type 2 diabetes. In this, decreased rates of energy expenditure and impaired insulin secretion could play a role. METHODS: In 10 male twin pairs discordant for the Trp64Arg polymorphism, we examined insulin response to glucose by an oral glucose tolerance test (OGTT), a frequently sampled intravenous glucose tolerance test (FSIGT), body composition by the bioimpedance method, dual-energy X-ray absorptiometry scanning and energy expenditure by indirect and direct calorimetry. RESULTS: Twins heterozygous for the Trp64Arg polymorphism showed significantly lower fat mass independent of the method used, and significantly lower fasting insulin and glucose concentrations compared with their homozygous wild-type co-twins. Correspondingly, insulin resistance and insulin secretion determined by homeostasis model assessment were significantly lower in twins carrying the Trp64Arg polymorphism. However, there were no significant differences in adiponectin levels, insulinogenic index assessed by OGTT, or insulin sensitivity, acute insulin response to glucose, glucose effectiveness or insulin disposition index assessed by minimal modelling of the FSIGT. Furthermore, there were no differences in sleeping, resting or post-prandial energy expenditure. CONCLUSIONS: In male twins with a high similarity in genetic and environmental background, the Trp64Arg polymorphism of the beta3AR gene is associated with lower fat mass, fasting insulin levels and an appropriate insulin response to glucose. Thus, heterozygosity for the Trp64Arg variant is unlikely to increase the risk of obesity, insulin resistance or type 2 diabetes.

Haplotype effects on human survival: logistic regression models applied to unphased genotype data.

Haplotype based linkage disequilibrium (LD) mapping exhibits higher power than the single locus approach because it makes use of the LD information contained in the flanking markers. New statistical methods have been proposed to help to infer haplotype effects on human diseases using multi-locus genotype data collected from unrelated individuals. In this paper, we introduce a statistical procedure for measuring haplotype effects on human survival using the popular logistic regression model with haplotype based parameterizations. By modeling haplotype frequency as a function of age, our model infers haplotype effects by estimating and testing the slope parameters under different genetic mechanisms (multiplicative, dominant, or recessive). In addition, by estimating the sex-specific slope parameters, our model allows the detection of sex-specific haplotype effects or haplotype-sex interactions. As an example, we apply our model to an empirical dataset on a stress related gene, interleukin-6, to look for haplotypes that affect individual survival and for haplotype-sex interactions. We show that our logistic regression based haplotype model can be a helpful tool for researchers interested in the genetics of human aging and longevity.

Mephenytoin and sparteine oxidation: genetic polymorphisms in Denmark.

The oxidation of mephenytoin was polymorphic in 358 healthy Danish volunteers. The ratio between the chromatographic peak areas of (S)- and (R)-mephenytoin (S/R) in 12 h urine was less than or equal to 0.48 in 349 extensive metabolizers (EM) and greater than or equal to 1 in 9 (2.5%) poor metabolizers (PM). Concomitant intake of mephenytoin and sparteine and subsequent assay by gas chromatography had no influence on the test results (mephenytoin S/R ratio or sparteine metabolic ratio). Among ten parents and seven siblings to six unrelated PM of mephenytoin only one (1/17 = 5.9%) was a PM. The pedigrees were compatible with an autosomal recessive mode of inheritance.