Screening for abdominal aortic aneurysm: lessons from a population-based study

Pathogenesis and management of abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) causes ∼170 000 deaths annually worldwide. Most guidelines recommend asymptomatic small AAAs (30 to <50 mm in women; 30 to <55 mm in men) are monitored by imaging and large asymptomatic, symptomatic, and ruptured AAAs are considered for surgical repair. Advances in AAA repair techniques have occurred, but a remaining priority is therapies to limit AAA growth and rupture. This review outlines research on AAA pathogenesis and therapies to limit AAA growth. Genome-wide association studies have identified novel drug targets, e.g. interleukin-6 blockade. Mendelian randomization analyses suggest that treatments to reduce low-density lipoprotein cholesterol such as proprotein convertase subtilisin/kexin type 9 inhibitors and smoking reduction or cessation are also treatment targets. Thirteen placebo-controlled randomized trials have tested whether a range of antibiotics, blood pressure-lowering drugs, a mast cell stabilizer, an anti-platelet drug, or fenofibrate slow AAA growth. None of these trials have shown convincing evidence of drug efficacy and have been limited by small sample sizes, limited drug adherence, poor participant retention, and over-optimistic AAA growth reduction targets. Data from some large observational cohorts suggest that blood pressure reduction, particularly by angiotensin-converting enzyme inhibitors, could limit aneurysm rupture, but this has not been evaluated in randomized trials. Some observational studies suggest metformin may limit AAA growth, and this is currently being tested in randomized trials. In conclusion, no drug therapy has been shown to convincingly limit AAA growth in randomized controlled trials. Further large prospective studies on other targets are needed.

The neglected association between central obesity markers and abdominal aortic aneurysm presence: A systematic review and meta-analysis

Purpose

To review the association between central obesity and abdominal aortic aneurysm (AAA).

Materials and methods

The PubMed, Web of Sciences, Embase, The China national knowledge infrastructure (CNKI), and Cochrane Library were searched up to April 30, 2022. Researches includes investigation of the relationship between central obesity markers and AAA. Included studies must use recognized measures of central obesity, i.e., waist circumference (WC) and waist-to-hip ratio (WHR), or use imaging techniques to calculate abdominal fat distribution, such as computed tomography (CT) imaging.

Results

Eleven clinical researches were identified of which eight discussed the association between physical examination and AAA, and three studies mainly focused on abdominal fat volume (AFV). Seven researches concluded that there was a positive correlation between markers of central obesity and AAA. Three studies found no significant link between markers of central obesity and AAA. One of the remaining studies reported different results for each sex. Three studies pooled in a meta-analysis identified correlation between central obesity and AAA presence (RR = 1.29; 95% confidence interval, 1.14-1.46).

Conclusion

Central obesity plays a role in the risk of AAA. Standardized central obesity markers may be predictors of AAA. However, there was no association between abdominal fat volume and AAA. Additional relevant evidence and specific mechanisms warrant further study.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?IDCRD42022332519, identifier CRD42022332519.

Identification of biomarkers and analysis of infiltrated immune cells in stable and ruptured abdominal aortic aneurysms

Objectives

The mortality rate of abdominal aortic aneurysm (AAA) is extremely high in the older population. This study aimed to identify potential biomarkers of AAA and aortic rupture and analyze infiltration of immune cells in stable and ruptured AAA samples.

Methods

Raw data of GSE47472, GSE57691, and GSE98278 were downloaded. After data processing, the co-expression gene networks were constructed. Gene Ontology and pathway enrichment analysis of AAA- and aortic rupture-related gene modules were conducted using the Database for Annotation, Visualization, and Integrated Discovery. Gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA) were used for further enrichment analysis. The CIBERSORT tool was used to analyze the relative abundance of immune cells in samples. Differentially expressed immune-related genes were analyzed between different samples. Predictive models were constructed via extreme gradient boosting, and hub genes were identified according to feature importance.

Results

Blue and yellow modules were significantly related to AAA, and genes in these modules were associated with the aortic wall and immune response, respectively. In terms of aortic rupture, the most relevant module was significantly enriched in the inflammatory response. The results of GSEA and GSVA suggested that immune cells and the inflammatory response were involved in the development of AAA and aortic rupture. There were significant differences in the infiltration of immune cells and expression levels of immune-related genes among different samples. NFKB1 might be an important transcription factor mediating the inflammatory response of AAA and aortic rupture. After the construction of a predictive model, CD19, SELL, and CCR7 were selected as hub genes for AAA whereas OAS3, IFIT1, and IFI44L were identified as hub genes for aortic rupture.

Conclusion

Weakening of the aortic wall and the immune response both contributed to the development of AAA, and the inflammatory response was closely associated with aortic rupture. The infiltration of immune cells was significantly different between different samples. NFKB1 might be an important transcription factor in AAA and aortic rupture. CD19, SELL, and CCR7 had potential diagnostic value for AAA. OAS3, IFIT1, and IFI44L might be predictive factors for aortic rupture.

D-Dimer Is a Diagnostic Biomarker of Abdominal Aortic Aneurysm in Patients With Peripheral Artery Disease

Background

Etiology and risk factors of peripheral artery disease (PAD) include age, smoking, and hypertension, etc. , which are shared by an abdominal aortic aneurysm (AAA). Concomitance with AAA in patients with PAD is not rare but is easily overlooked in the clinical situation, though management strategies are altered totally. This study aims to investigate diagnostic biomarkers for the prediction of AAA in patients with PAD.

Methods

A total of 684 patients diagnosed with AAA and/or PAD were enrolled and analyzed retrospectively. Each patient with PAD and AAA was gender and age-matched. Demographic data, medical history, and serum laboratory test profiles were obtained. Statistical analysis was performed to determine diagnostic biomarkers of AAA in patients with PAD.

Results

Firstly, 320 patients with PAD-only and 320 patients with AAA-only were compared. Levels of bilirubin and D-Dimer were decreased, while the incidence of diabetes mellitus, levels of fibrinogen, and platelet count were increased significantly in patients with PAD-only compared with those in patients with AAA-only (P &lt; 0.001). Next, 364 patients with PAD (44 patients with AAA) and 364 patients with AAA (44 patients with PAD) were compared. Multivariate logistic regression analysis confirmed the differential distribution of bilirubin, D-dimer, fibrinogen, and platelet count between patients with AAA and patients with PAD (P &lt; 0.05). Receiver operator curves (ROC) showed that the area under the curve (AUC) of total bilirubin, direct bilirubin, D-dimer, fibrinogen, and platelet count was 0.6113, 0.5849, 0.7034, 0.6473, and 0.6785, respectively. Finally, to further validate the predictive efficacy of mentioned markers, a multivariable logistics regression analysis was performed between the PAD only group and the PAD with AAA group. The results suggested increased levels of D-dimer in the PAD with AAA group compared to the PAD only group (OR: 2.630, 95% CI:1.639–4.221; P &lt; 0.001). In particular, the Youden index suggested that the cut-off value of D-dimer for predicting AAA in patients with PAD was 0.675 mg/L with a sensitivity of 76.9% and a specificity of 84.9% (AUC = 0.8673; 95% CI, 0.8106–0.9240, P &lt; 0.001). In all 364 patients with PAD, 41.46% patients were diagnosed AAA when D-dimer is &gt;0.675 mg/L, while only 3.55% patients were diagnosed AAA when D-dimer ≤ 0.675 mg/L.

Conclusions

PAD and AAA exert different clinical and serum profiles; D-dimer (&gt;0.675 mg/L) is a reliable biomarker for the prediction of AAA in patients with PAD.

Abdominal aorta measurements by a handheld ultrasound device compared with a conventional cart-based ultrasound machine

BACKGROUND

Ultraportable or pocket handheld ultrasound devices (HUD) may be useful for large-scale abdominal aortic aneurysm screening. However, the reproducibility of measurements has not been compared with conventional cart-based ultrasound machines.

OBJECTIVES

Investigate the intra- and inter-operator reproducibility of a HUD compared with a conventional ultrasound machine for aortic screening.

DESIGN

Analytical, cross-sectional.

SETTING

Ultrasound department at a large tertiary care hospital in Riyadh.

PATIENTS AND METHODS

Eligible male participants aged ≥60 years were invited to participate upon arriving for a non-vascular ultrasound appointment. Three repeated anteroposterior measurements of the transverse aorta were made at the proximal and distal locations for each machine before repeating the measurements on a subset of participants by a second blinded operator. Intraclass correlation coefficients (ICC) and the Bland-Altman method were used to analyze reproducibility.

MAIN OUTCOME MEASURE

Inter-system and intra- and inter-operator ICCs.

SAMPLE SIZE

114 males with repeated measurements by second operator on a subset of 35 participants.

RESULTS

The median age (interquartile range) of participants was 68 years (62-74 years). The intra- and inter-operator ICCs were all >0.800 showing almost perfect agreement except for the inter-operator reproducibility at the proximal location using a conventional machine (ICC= 0.583, P=.007) and the Butterfly device (ICC=0.467, P=.037). The inter-system ICCs (95% CI) were 0.818 (0.736-0.874) and 0.879 (0.799-0.924) at the proximal and distal locations, respectively. The mean difference in aortic measurement between the ultrasound systems was 0.3 mm (1.7%) in the proximal location and 0.6 mm (3.6%) in the distal location. In total, >91% of the difference in measurements between the machines was <3 mm. The mean scanning time was 4:16 minutes for the conventional system and 3:53 minutes for the HUD (P=.34).

CONCLUSIONS

Abdominal aortic screening using a HUD was feasible and reliable compared with a conventional ultrasound machine. A pocket HUD should be considered for large-scale screening.

LIMITATIONS

No cases of abdominal aortic aneurysm in the sample and lack of blinding.

CONFLICT OF INTEREST

None.

Lack of an effective drug therapy for abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) rupture is a common cause of death in adults. Current AAA treatment is by open surgical or endovascular aneurysm repair. Rodent model and human epidemiology, and genetic and observational studies over the last few decades have highlighted the potential of a number of drug therapies, including medications that lower blood pressure, correct dyslipidaemia, or inhibit thrombosis, inflammation or matrix remodelling, as approaches to managing small AAA. This review summarizes prior AAA pathogenesis data from animal and human studies aimed at identifying targets for the development of drug therapies. The review also systematically assesses past randomized placebo-controlled drug trials in patients with small AAAs. Eleven previously published randomized-controlled clinical trials testing different drug therapies aimed at slowing AAA progression were identified. Five of the trials tested antibiotics and three trials assessed medications that lower blood pressure. Meta-analyses of these trials suggested that neither of these approaches limit AAA growth. Allocation to blood pressure-lowering medication was associated with a small reduction in AAA rupture or repair, compared to placebo (relative risk 0.94, 95% confidence intervals 0.89, 1.00, P = 0.047). Three further trials assessed the effect of a mast cell inhibitor, fibrate or platelet aggregation inhibition and reported no effect on AAA growth or clinical events. Past trials were noted to have a number of design issues, particularly small sample sizes and limited follow-up. Much larger trials are needed to properly test potential therapeutic approaches if a convincingly effective medical therapy for AAA is to be identified.

Association between metformin and abdominal aortic aneurysm in diabetic and non-diabetic US veterans

We sought to examine the progression from abdominal aortic aneurysm (AAA) diagnosis to surgery and death among diabetics with and without exposure to metformin as well as non-diabetics. We conducted a retrospective cohort study (January 2000 to July 2019) comparing 3 transitions (AAA surgery, death, and death after AAA surgery) among propensity score-matched metformin-exposed and unexposed diabetic veterans and non-diabetic veterans using the VA Informatics and Computing Infrastructure database. We fit an adjusted Cox proportional hazards model with transition-specific effects. There were 43,073 metformin-unexposed diabetics, 24,361 metformin-exposed diabetics and 56,006 non-diabetics. Compared with the non-diabetic cohort, both diabetic cohorts have a lower risk of surgery (no metformin (HR=0.740, 95% CI 0.706 to 0.776); with metformin (HR=0.770, 95% CI 0.730 to 0.813)). However, the non-metformin diabetic cohort has a higher risk of death (HR=1.024, 95% CI 1.004 to 1.045) and death after surgery (HR=1.086, 95% CI 1.013 to 1.165). The metformin-exposed diabetic cohort has a lower risk of death in the first 10 years after AAA diagnosis (HR=0.877, 95% CI 0.855 to 0.899), yet a higher risk of death 10 years after AAA diagnosis (HR=1.177, 95% CI 1.092 to 1.270) compared with non-diabetic cohort. Non-diabetics have the highest rate of AAA surgery compared with both diabetic cohorts. However, diabetics without metformin have the highest risk of death prior to, and after surgery. This research provides novel findings for patients diagnosed with AAA. The use of metformin after both AAA diagnosis and surgery should be further investigated.

Matrix Metalloproteinase in Abdominal Aortic Aneurysm and Aortic Dissection

Abdominal Aortic Aneurysm (AAA) affects 4–5% of men over 65, and Aortic Dissection (AD) is a life-threatening aortic pathology associated with high morbidity and mortality. Initiators of AAA and AD include smoking and arterial hypertension, whilst key pathophysiological features of AAA and AD include chronic inflammation, hypoxia, and large modifications to the extra cellular matrix (ECM). As it stands, only surgical methods are available for preventing aortic rupture in patients, which often presents difficulties for recovery. No pharmacological treatment is available, as such researchers are attempting to understand the cellular and molecular pathophysiology of AAA and AD. Upregulation of matrix metalloproteinase (MMPs), particularly MMP-2 and MMP-9, has been identified as a key event occurring during aneurysmal growth. As such, several animal models of AAA and AD have been used to investigate the therapeutic potential of suppressing MMP-2 and MMP-9 activity as well as modulating the activity of other MMPs, and TIMPs involved in the pathology. Whilst several studies have offered promising results, targeted delivery of MMP inhibition still needs to be developed in order to avoid surgery in high risk patients.

Sex hormones and incident dementia in older men: The health in men study

BACKGROUND

Low circulating testosterone has been associated with dementia in older men but existing evidence from prospective studies is inconsistent.

METHODS

We conducted a prospective longitudinal study of 4069 community-dwelling older men free of dementia aged 71-88 years at baseline. The main objective of the study was to determine if men with low circulating sex hormones were more likely to develop dementia over time. The main biochemical exposures of interest were collected at baseline between 2001 and 2004 and men were assessed for incident dementia via an electronic health records database to the 31 st of December 2013.

RESULTS

Dementia developed in 499 men over a median of 10.5 years (range 9.4-12.2 years). The risk of developing dementia increased with decreasing total (hazard ratio [HR] 1.14, 95% confidence interval [95%CI] 1.03-1.26 per standard deviation decrease) and calculated free testosterone (HR 1.18, 95%CI 1.06-1.31 per standard deviation decrease) after adjustment for age, baseline cognitive function, depression, body mass, hypertension, cardiovascular disease and total plasma homocysteine. Men in the lowest quartiles of total (adjusted HR 1.39, 95%CI 1.04-1.85) and calculated free testosterone (adjusted HR 1.43, 95%CI 1.08-1.90) had increased risk of developing dementia compared to those in the highest quartiles.

CONCLUSIONS

Lower plasma total and calculated free testosterone were associated with increased risk of developing dementia independent of relevant measured clinical and biochemical factors and was not explained due to differential mortality in those with lower testosterone levels. The association between low testosterone and dementia is biologically plausible but data on the role of testosterone treatment in preventing dementia is lacking and adequately powered trials in men at risk would be welcome.

Sex differences in national rates of repair of emergency abdominal aortic aneurysm

BACKGROUND

The aim of this study was to assess the sex differences in both the rate and type of repair for emergency abdominal aortic aneurysm (AAA) in England.

METHODS

Hospital Episode Statistics (HES) data sets from April 2002 to February 2015 were obtained. Clinical and administrative codes were used to identify patients who underwent primary emergency definitive repair of ruptured or intact AAA, and patients with a diagnosis of AAA who died in hospital without repair. These three groups included all patients with a primary AAA who presented as an emergency. Sex differences between repair rates and type of surgery (endovascular aneurysm repair (EVAR) versus open repair) over time were examined.

RESULTS

In total, 15 717 patients (83·3 per cent men) received emergency surgical intervention for ruptured AAA and 10 276 (81·2 per cent men) for intact AAA; 12 767 (62·0 per cent men) died in hospital without attempted repair. The unadjusted odds ratio for no repair in women versus men was 2·88 (95 per cent c.i. 2·75 to 3·02). Women undergoing repair of ruptured AAA were older and had a higher in-hospital mortality rate (50·0 versus 41·0 per cent for open repair; 30·9 versus 23·5 per cent for EVAR). After adjustment for age, deprivation and co-morbidities, the odds ratio for no repair in women versus men was 1·34 (1·28 to 1·40). The in-hospital mortality rate after emergency repair of an intact AAA was also higher among women.

CONCLUSION

Women who present as an emergency with an AAA are less likely to undergo repair than men. Although some of this can be explained by differences in age and co-morbidities, the differences persist after case-mix adjustment.

Abdominal Aortic Aneurysm: Evolving Controversies and Uncertainties

Abdominal aortic aneurysm (AAA) is defined as a permanent dilatation of the abdominal aorta that exceeds 3 cm. Most AAAs arise in the portion of abdominal aorta distal to the renal arteries and are defined as infrarenal. Most AAAs are totally asymptomatic until catastrophic rupture. The strongest predictor of AAA rupture is the diameter. Surgery is indicated to prevent rupture when the risk of rupture exceeds the risk of surgery. In this review, we aim to analyze this disease comprehensively, starting from an epidemiological perspective, exploring etiology and pathophysiology, and concluding with surgical controversies. We will pursue these goals by addressing eight specific questions regarding AAA: (1) Is the incidence of AAA increasing? (2) Are ultrasound screening programs for AAA effective? (3) What causes AAA: Genes versus environment? (4) Animal models: Are they really relevant? (5) What pathophysiology leads to AAA? (6) Indications for AAA surgery: Are surgeons over-eager to operate? (7) Elective AAA repair: Open or endovascular? (8) Emergency AAA repair: Open or endovascular?

Investigation of TGFβR2 SNP rs4522809, Osteopontin, TGF β1 and their association with dilatative pathology of ascending thoracic aorta

BACKGROUND

Dilatative pathology of the ascending thoracic aorta (DPATA) is characterized by the aortic wall expansion more than 1.5 and could be accompanied by aortic wall rupture. Mutations of TGFBR2 gene demonstrated an association with syndromic DPATA and altered pathway of transforming growth factor beta (TGF-β). Elevated TGF-β1 level has been found in blood samples in DPATA group. Moreover, elevated osteopontin (OPN) level was associated with mutations of TGFBR2 gene. Based on recently published findings, we aimed to evaluate genotyping results of TGFBR2 rs4522809 and the association with circulating OPN and TGF-β1 concentrations within DPATA patients.

METHODS AND FINDINGS

TGFBR2 SNP genotyping assay was performed by quantitative real-time PCR, TGF-β1 and OPN concentrations were measured using enzyme-linked immunosorbent assay. Genotyping results showed G allele to be associated with DPATA (p = .01), the presence of G allele significantly increased the possibility of DPATA by 1.67 times (OR = 1.67, 95%, CI = 1.12-2.47). TGF-β1 concentration was significantly higher in DPATA subjects compared with Reference group (p = 0,001). Finally, we found moderate inverse correlation (r = -0,524) between circulating TGF-β1 and OPN levels within DPATA subjects (p = 0,002), as increasing levels of TGF-β1 cytokine significantly decrease concentration of OPN.

CONCLUSIONS

This is the first report on the association between previously defined TGFβR2 SNP rs4522809 linked with dilatation of ascending thoracic aorta. Also, for the first time we report the inversed correlation between circulating TGF-β1 and OPN concentrations in DPATA subjects indicating the possible biomarkers for DPATA.

Identification of the main determinants of abdominal aorta size: a screening by Pocket Size Imaging Device

Background

Ultrasound exam as a screening test for abdominal aorta (AA) can visualize the aorta in 99% of patients and has a sensitivity and specificity approaching 100% in screening settings for aortic aneurysm. Pocket Size Imaging Device (PSID) has a potential value as a screening tool, because of its possible use in several clinical settings. Our aim was to assess the impact of demographics and cardiovascular (CV) risk factors on AA size by using PSID in an outpatient screening.

Methods

Consecutive patients, referring for a CV assessment in a 6 months period, were screened. AA was visualized by subcostal view in longitudinal and transverse plans in order to determine the greatest anterior-posterior diameter. After excluding 5 patients with AA aneurysm, 508 outpatients were enrolled. All patients underwent a sequential assessment including clinical history with collection of CV risk factors, physical examination, PSID exam and standard Doppler echoc exam using a 2.5 transducer with harmonic capability, both by expert ultrasound operators, during the same morning. Standard echocardiography operators were blinded on PSID exam and viceversa.

Results

Diagnostic accuracy of AA size by PSID was tested successfully with standard echo machine in a subgroup (n = 102) (rho = 0.966, p < 0.0001). AA diameter was larger in men than in women and in ≥50 -years old subjects than in those <50 -years old (both p < 0.0001). AA was larger in patients with coronary artery disease (CAD) (p < 0.0001). By a multivariate model, male sex (p < 0.0001), age and body mass index (both p < 0.0001), CAD (p < 0.01) and heart rate (p = 0.018) were independent predictors of AA size (cumulative R² = 0.184, p < 0.0001).

Conclusion

PSID is a reliable tool for the screening of determinants of AA size. AA diameter is greater in men and strongly influenced by aging and overweight. CAD may be also associated to increased AA diameter.

Everyday Impact of Cognitive Interventions in Mild Cognitive Impairment: a Systematic Review and Meta-Analysis

Cognitive interventions in Mild Cognitive Impairment (MCI) seek to ameliorate cognitive symptoms in the condition. Cognitive interventions may or may not generalize beyond cognitive outcomes to everyday life. This systematic review and meta-analysis sought to assess the effect of cognitive interventions compared to a control group in MCI on generalizability outcome measures [activities of daily living (ADLs), mood, quality of life (QOL), and metacognition] rather than cognitive outcomes alone. PRISMA guidelines were followed. MEDLINE and PsychInfo were utilized as data sources to locate references related to cognitive interventions in individuals with MCI. The cognitive intervention study was required to have a control or alternative treatment comparison group to be included. Thirty articles met criteria, including six computerized cognitive interventions, 14 therapist-based interventions, and 10 multimodal (i.e., cognitive intervention plus an additional intervention) studies. Small, but significant overall median effects were seen for ADLs (d = 0.23), mood (d = 0.16), and metacognitive outcomes (d = 0.30), but not for QOL (d = 0.10). Computerized studies appeared to benefit mood (depression, anxiety, and apathy) compared to controls, while therapist-based interventions and multimodal interventions had more impact on ADLs and metacognitive outcomes than control conditions. The results are encouraging that cognitive interventions in MCI may impact everyday life, but considerably more research is needed. The current review and meta-analysis is limited by our use of only PsychInfo and MEDLINE databases, our inability to read full text non-English articles, and our reliance on only published data to complete effect sizes.

Association of diabetes mellitus with presence, expansion, and rupture of abdominal aortic aneurysm: "Curiouser and curiouser!" cried ALICE

Both coronary artery and peripheral artery disease are representative atherosclerotic diseases that are positively associated with presence of abdominal aortic aneurysm (AAA). Diabetes mellitus, which is one of major risk factors of coronary artery and peripheral artery diseases, however, has been curiously suggested to be negatively associated with AAA, despite the positive associations of coronary artery and peripheral artery diseases with presence of AAA. In the present article, we overviewed epidemiologic evidence (meta-analyses) regarding the associations of diabetes mellitus with presence, expansion, and rupture of AAA through a systematic literature search. Our exhaustive search identified seven meta-analyses. Main results of almost all meta-analyses (except for the two earliest ones) apparently found that diabetes mellitus is negatively associated with presence, expansion, and rupture of AAA.

Prospective longitudinal study of testosterone and incident depression in older men: The Health In Men Study

BACKGROUND

Depression in older men has been associated with low circulating testosterone concentration but data from prospective studies are limited.

METHODS

We conducted a prospective longitudinal study in a community representative cohort of 3179 older men free of clinically significant depressive symptoms at baseline. The main objective of this study was to determine if low serum testosterone, dihydrotestosterone and estradiol concentrations are associated with the development of depressive symptoms. Incident depression was assessed with the Patient Health Questionnaire and via an electronic health record database (The West Australian Data Linkage System). The main exposures of interest were serum testosterone, dihydrotestosterone and estradiol measured by liquid chromatography-mass spectrometry and calculated free testosterone in baseline blood samples (collected between 2001 and 2004).

RESULTS

One hundred and thirty five men (4.2%) developed depression over a median follow up time of 9.4 years (range 8.4-10.9). Men with incident depression were older (median age 77.7 vs 76.1 years, z=-3.82, p=0<0.001) and were more likely to have cardiovascular disease (43.0% vs 32.6%, χ(2)=6.32, p=0.012) and diabetes (22.2% vs 13.2%, χ(2)=8.95, p=0.003). Low serum total testosterone (<6.4 nmol/L) was associated with incident depression (HR 2.07, 95%CI 1.17-3.68) and this remained significant after adjustment for relevant potential confounding factors (HR 1.86, 95%CI 1.05-3.31). Low serum dihydrotestosterone, estradiol and calculated free testosterone were not associated with risk of depression.

CONCLUSIONS

Low serum total testosterone, but not calculated free testosterone, was associated with incident depression in this sample of older men.

Calculating when elective abdominal aortic aneurysm repair improves survival for individual patients: development of the Aneurysm Repair Decision Aid and economic evaluation

BACKGROUND

Abdominal aortic aneurysm (AAA) repair aims to prevent premature death from AAA rupture. Elective repair is currently recommended when AAA diameter reaches 5.5 cm (men) and 5.0 cm (women). Applying population-based indications may not be appropriate for individual patient decisions, as the optimal indication is likely to differ between patients based on age and comorbidities.

OBJECTIVE

To develop an Aneurysm Repair Decision Aid (ARDA) to indicate when elective AAA repair optimises survival for individual patients and to assess the cost-effectiveness and associated uncertainty of elective repair at the aneurysm diameter recommended by the ARDA compared with current practice.

DATA SOURCES

The UK Vascular Governance North West and National Vascular Database provided individual patient data to develop predictive models for perioperative mortality and survival. Data from published literature were used to model AAA growth and risk of rupture. The cost-effectiveness analysis used data from published literature and from local and national databases.

METHODS

A combination of systematic review methods and clinical registries were used to provide data to populate models and inform the structure of the ARDA. Discrete event simulation (DES) was used to model the patient journey from diagnosis to death and synthesised data were used to estimate patient outcomes and costs for elective repair at alternative aneurysm diameters. Eight patient clinical scenarios (vignettes) were used as exemplars. The DES structure was validated by clinical and statistical experts. The economic evaluation estimated costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) from the NHS, social care provider and patient perspective over a lifetime horizon. Cost-effectiveness acceptability analyses and probabilistic sensitivity analyses explored uncertainty in the data and the value for money of ARDA-based decisions. The ARDA outcome measures include perioperative mortality risk, annual risk of rupture, 1-, 5- and 10-year survival, postoperative long-term survival, median life expectancy and predicted time to current threshold for aneurysm repair. The primary economic measure was the ICER using the QALY as the measure of health benefit.

RESULTS

The analysis demonstrated it is feasible to build and run a complex clinical decision aid using DES. The model results support current guidelines for most vignettes but suggest that earlier repair may be effective in younger, fitter patients and ongoing surveillance may be effective in elderly patients with comorbidities. The model adds information to support decisions for patients with aneurysms outside current indications. The economic evaluation suggests that using the ARDA compared with current guidelines could be cost-effective but there is a high level of uncertainty.

LIMITATIONS

Lack of high-quality long-term data to populate all sections of the model meant that there is high uncertainty about the long-term clinical and economic consequences of repair. Modelling assumptions were necessary and the developed survival models require external validation.

CONCLUSIONS

The ARDA provides detailed information on the potential consequences of AAA repair or a decision not to repair that may be helpful to vascular surgeons and their patients in reaching informed decisions. Further research is required to reduce uncertainty about key data, including reintervention following AAA repair, and assess the acceptability and feasibility of the ARDA for use in routine clinical practice.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Insulin resistance and depressive symptoms in older men: the health in men study

OBJECTIVE

A positive association between depression and diabetes has been reported, but the direction and nature of this association is unclear. Insulin resistance is a state of reduced responsiveness of target tissues to normal circulating levels of insulin and predisposes to diabetes in the presence of beta cell dysfunction.

METHODS

We conducted this cross-sectional and prospective study in a community representative sample of 3,140 older men free of diabetes to determine if insulin resistance was associated with prevalent and incident depressive symptoms.

RESULTS

Men with insulin resistance had increased odds of depression cross-sectionally (odds ratio [OR]: 1.61; 95% confidence interval [CI]: 1.08-2.40), although this was not significant after adjustment for possible confounding (OR: 1.32; 95% CI: 0.85-2.03). In the longitudinal analysis, men with insulin resistance were more likely to develop clinically significant depressive symptoms (adjusted risk ratio [RR]: 2.33; 95% CI: 1.17-4.62), and this risk was greatest for men in the highest quartile of insulin resistance compared with those in the lowest quartile (adjusted RR: 2.54; 95% CI: 1.04-6.18).

CONCLUSION

Older men with clinically significant depressive symptoms were more likely to have higher markers of insulin resistance. Additionally, the odds of depression increased with increasing levels of insulin resistance, and insulin resistance increased the risk of developing depression over 5 years later. Because depression is now a leading cause of disability worldwide, addressing the rising challenge of insulin resistance may prove important in improving the future health of our communities.

Screening for abdominal aortic aneurysm

Guidelines are systematically developed statements to assist patients and providers in choosing appropriate health care for specific clinical conditions. Consensus exists across guidelines on one-time screening of elderly men to detect and treat abdominal aortic aneurysm (AAA) ≥5.5 cm. However, the recommendations regarding other age groups, imaging intervals for small AAAs, inclusion of women, and cost-effectiveness have not been universally adopted. As many countries are considering the initiation of an AAA screening program, this is an overview on the current status of such programs.

The PACE study: a randomized clinical trial of cognitive activity strategy training for older people with mild cognitive impairment

OBJECTIVE

The role of cognition-focused interventions in reducing cognitive decline in older people remains uncertain. This study aimed to clarify whether a group cognitive activity (CA) strategy-training program would decrease the 2-year rate of cognitive decline of people with mild cognitive impairment (MCI).

DESIGN

Randomized controlled trial.

SETTING

One study site.

PARTICIPANTS

160 older adults with MCI ≥65 years of age (mean: 75, SD: 5.8).

INTERVENTION

Five-week CA strategy training or a control nonspecific educational program. The primary outcome measure was change from baseline in the total score on the Cambridge Cognitive Examination-Revised (CAMCOG-R). Secondary outcomes of interest included changes in memory, attention, executive functions, mood, and quality of life. Endpoints were collected 10, 52, and 104 weeks post baseline.

RESULTS

Intention to treat analysis identified no significant difference in CAMCOG-R scores over time between the two groups (mean difference: -0.36, 95% CI: -1.02,0.29) or across secondary outcome measures. The exceptions were better performance of the CA group on immediate attention (Digit Span Forwards, adjusted mean difference: 0.15, 95% CI: 0.01,0.30) and better quality of life (adjusted mean difference: 0.57, 95% CI: 0.10,1.04) compared with controls.

CONCLUSION

The devised program of CA did not improve general cognitive performance of older adults with MCI over a period of 2 years. Although favorable, the beneficial effects of the intervention on attention and quality of life were small, and of uncertain significance.

Advanced complicated diabetes mellitus is associated with a reduced risk of thoracic and abdominal aortic aneurysm rupture: a population-based cohort study

BACKGROUND

Studies have associated diabetes mellitus (DM) with the reduced risk of abdominal aortic aneurysm and thoracic aortic aneurysm and dissection. We used the national insurance data of Taiwan to examine these correlations for an Asian population. The association was also evaluated by DM severity.

METHODS

We identified 160,391 patients with type 2 DM diagnosed from 1998 to 2008 and 646,710 comparison subjects without DM, frequency matched by diagnosis date, sex and age (mainly the elderly). The DM severity was partitioned into advanced and uncomplicated status according to DM-related comorbidities.

RESULTS

By the end of 2010, the overall pooled incidence rate of thoracic aortic aneurysm and abdominal aortic aneurysm was 15% lower in the type 2 DM cohort than in non-DM cohort, with an adjusted hazard ratio of 0.64 [95% confidence interval (CI) 0.56-0.74] in the multivariable Cox model. Patients with advanced type 2 DM were significantly associated with reduced thoracic aortic aneurysm rupture and abdominal aortic aneurysm without rupture, with adjusted hazard ratios of 0.50 (95% CI 0.35-0.71) and 0.53 (95% CI 0.40-0.69), respectively. Uncomplicated type 2 DM was also associated with reduced abdominal aortic aneurysm without rapture (aHR = 0.58, 95% CI 0.45-0.74).

CONCLUSIONS

Our results demonstrate that patients with diabetes in this Asian population have reduced prevalence of thoracic and abdominal aortic aneurysms. The observed paradoxical inverse relationship between severity of DM and aortic aneurysms is clear. Further research is required to investigate the underlying mechanisms for the reduced risk of aortic aneurysms associated with diabetes.

Aortic aneurysm screening in a high-risk population: a non-contrast computed tomography study in korean males with hypertension

BACKGROUND AND OBJECTIVES

Screening strategies for aortic aneurysm (AA) according to risk factors and ethnicity are controversial. This study explored the prevalence of AA and determined whether screening is necessary in a population of multiple risk factors.

SUBJECTS AND METHODS

From June, 2012 to April, 2013, 542 consecutive elderly (≥65 years) male hypertensive patients without a history of AA were prospectively enrolled. After excluding 15 patients (2.8%) with aortic valve surgery, 30 patients (5.5%) with suboptimal computed tomography (CT) images, the remaining 496 patients (age 73±5 years) comprised the study population. Maximal diameters of the thoracic and abdominal aorta were measured using non-contrast CT.

RESULTS

The prevalence of thoracic AA (TAA, diameter ≥40 mm) and abdominal AA (AAA, diameter ≥30 mm) was 36.5% (181/496) and 6.0% (30/496), respectively. In the multivariate logistic regression analysis, determinants for TAA were age {odds ratio (OR) 1.059, 95% confidence interval (CI) 1.018-1.101, p=0.005}, dyslipidemia (OR 0.621, 95% CI 0.418-0.923, p=0.018), body surface area (OR 11.92, 95% CI 2.787-50.97, p=0.001), diastolic blood pressure (OR 1.029, 95% CI 1.009-1.049, p=0.004) and AAA (OR 3.070, 95% CI 1.398-6.754, p=0.005). In contrast, AAA was independently associated with dysplipidemia (OR 2.792, 95% CI 1.091-7.143, p=0.032), current/past smokerfs (OR 4.074, 95% CI 1.160-14.31, p=0.028), and TAA (OR 3.367, 95% CI 1.550-7.313, p=0.002).

CONCLUSION

The prevalence of AA was significant and TAA was more prevalent than AAA in elderly Korean males with hypertension. Future research should establish distinct screening strategies for TAA and AAA according to risk factors and ethnicity.

Influence of apolipoprotein E, age and aortic site on calcium phosphate induced abdominal aortic aneurysm in mice

OBJECTIVE

To assess relevant features of abdominal aortic aneurysms (AAA) induced by calcium phosphate within a mouse model. Specifically we investigated: (1) whether apolipoprotein E deficiency and older age promoted AAA formation, and (2) whether the local application of calcium phosphate affected the size of distant aortic segments.

METHODS

AAA was induced by application of calcium phosphate to the infra-renal aortas of 3 and 7 month old male mice. AAA induction was assessed by calculating expansion of the infra-renal aortic diameter over 1-4 weeks. Aortic samples were assessed to quantify calcification, macrophages infiltration, elastic lamellar degradation and apoptosis. Blood pressure was measured by the tail cuff method, and plasma concentrations of total cholesterol, low density lipoprotein and very low density lipoprotein cholesterol, and pro-inflammatory cytokines were measured using commercially available kits. The maximum diameters of the aortic arch, thoracic and supra-renal aorta at sacrifice were measured by morphometry and the mean maximal diameter of these three aortic segments was calculated.

RESULTS

The median expansion of the infra-renal aorta 2 weeks after AAA induction was significantly greater in apolipoprotein E deficient (ApoE(-/-)) mice than in age- and gender-matched wild type controls [275.8% (IQR 193.8%-348.5%) versus 94.7% (IQR 47.8%-163.4%), P = 0.02]. The greater aortic expansion in ApoE(-/-) mice was associated with aortic calcification, macrophage infiltration, elastic lamellar degradation and apoptosis of cells in the media and adventitia. The plasma low density lipoprotein/very low density lipoprotein cholesterol concentrations 2 weeks after AAA induction were positively correlated with the expansion of the infra-renal aorta induced by calcium phosphate. The median expansion of the infra-renal aorta 2 weeks after AAA induction was similar in 3 and 7 month old wild type mice. The local administration of calcium phosphate was associated with an increase in the mean maximal diameter of distant aortic segments, but not associated with changes in the concentrations of pro-inflammatory markers in either the plasma or the spleen.

CONCLUSION

This study suggests that apolipoprotein E deficiency, but not age, predisposes to AAA induced within the calcium phosphate model. Increased AAA expansion in ApoE(-/-) mice was associated with calcification, macrophage infiltration, elastic lamellar degradation, and cell apoptosis. Local application of calcium phosphate also promoted dilation of distant aortic segments.

Low vitamin D status is an independent predictor of increased frailty and all-cause mortality in older men: the Health in Men Study

CONTEXT AND OBJECTIVE

Hypovitaminosis D and frailty are common in the older population. We aimed to determine whether 25-hydroxyvitamin D [25(OH)D] concentrations are associated with frailty and mortality.

DESIGN

We conducted a prospective cohort study.

SETTING AND PARTICIPANTS

Participants included 4203 older men aged 70-88 years in Perth, Western Australia.

MAIN OUTCOME MEASURES

25(OH)D was measured by immunoassay. Frailty was assessed with the 5-point FRAIL (fatigue, resistance, ambulation, illness, and loss of weight) scale. Mortality was determined from the death registry via the Western Australian Data Linkage System.

RESULTS

At baseline, 676 (16.1%) men were frail, as defined by having ≥3 deficits (FRAIL scale ≥ 3). In multivariate cross-sectional analysis, low vitamin D status, defined by the lowest quartile of 25(OH)D values (<52.9 nmol/L), was associated with increased prevalent frailty (odds ratio, 1.96; 95% confidence interval [CI], 1.52 to 2.52) in comparison to the highest quartile of 25(OH)D values (>81.6 nmol/L). After a mean period of 5.3 years, the adjusted odds ratio of being frail at follow-up for men with low vitamin D and having zero deficit at baseline (FRAIL scale = 0) was 1.56 (95% CI, 1.07 to 2.27). Low vitamin D also predicted all-cause mortality over a period of up to 9.2 years (hazard ratio, 1.20; 95% CI, 1.02 to 1.42), independent of baseline frailty and other covariates.

CONCLUSION

Hypovitaminosis D is associated with prevalent and incident frailty in older men. Hypovitaminosis D also predicts all-cause mortality, independent of frailty. The association between vitamin D and mortality is not solely dependent on the occurrence of frailty.

Understanding the effects of tobacco smoke on the pathogenesis of aortic aneurysm

Aneurysmal arterial disease is a vascular degenerative condition that is distinct from atherosclerotic and other occlusive arterial diseases. There is regionalization of the predisposition to aneurysm formation within the vascular tree, and the pathological process varies with location. Infrarenal abdominal aortic aneurysm (AAA) is the most common manifestation of aneurysmal disease, and smoking is the dominant risk factor. Smoking is a much greater risk factor for AAA than for atherosclerosis. In addition to playing a role in the pathogenesis of AAA, smoking also increases the rate of expansion and risk of rupture of established AAA. The mechanistic relationship between AAA and smoking is being established by the use of enhanced animal models that are dependent on smoke or smoke components. The mechanisms seem to involve durable alterations in vascular smooth muscle cell and inflammatory cell function. This review examines the clinical, epidemiological, and mechanistic evidence implicating smoking as a cause of aneurysms, focusing on AAA.

Influence of calendar period on the association between BMI and coronary heart disease: a meta-analysis of 31 cohorts

OBJECTIVE

The association between obesity and coronary heart disease (CHD) may have changed over time, for example due to improved pharmacological treatment of CHD risk factors. This meta-analysis of 31 prospective cohort studies explores the influence of calendar period on CHD risk associated with body mass index (BMI).

DESIGN AND METHODS

The relative risks (RRs) of CHD for a five-BMI-unit increment and BMI categories were pooled by means of random effects models. Meta-regression analysis was used to examine the influence of calendar period (>1985 v ≤1985) in univariate and multivariate analyses (including mean population age as a covariate).

RESULTS

The age, sex, and smoking adjusted RR (95% confidence intervals) of CHD for a five-BMI-unit increment was 1.28(1.22:1.34). For underweight, overweight and obesity, the RRs (compared to normal weight) were 1.11(0.91:1.36), 1.31(1.22:1.41), and 1.78(1.55:2.04), respectively. The univariate analysis indicated 31% (95%CI: -56:0) lower RR of CHD associated with a five-BMI-unit increment and a 51% (95%CI: -78: -14)) lower RR associated with obesity in studies starting after 1985 (n = 15 and 10, respectively) compared to studies starting in or before 1985 (n = 16 and 10). However, in the multivariate analysis, only mean population age was independently associated with the RRs for a five-BMI-unit increment and obesity (-29(95%CI: -55: -5)) and -31(95%CI: -66:3), respectively) per 10-year increment in mean age).

CONCLUSION

This study provides no consistent evidence for a difference in the association between BMI and CHD by calendar period. The mean population age seems to be the most important factor that modifies the association between the risk of CHD and BMI, in which the RR decreases with increasing age.

Is hypovitaminosis D associated with abdominal aortic aneurysm, and is there a dose-response relationship?

OBJECTIVE

This study aims to investigate the association between plasma 25-hydroxyvitamin D (25(OH)D) concentrations with the presence of abdominal aortic aneurysm (AAA) and aortic diameter.

DESIGN

An observational study of 4233 community-dwelling men aged 70-88 years, who participated in a randomised controlled trial of screening for AAA.

METHODS

Infrarenal aortic diameter measured by ultrasound and 25(OH)D by immunoassay.

RESULTS

A total of 311 men (7.4%) with AAA (defined as aortic diameter ≥ 30 mm) comprised the study. Multivariable models were adjusted for age, smoking, cardiovascular disease, hypertension, diabetes, dyslipidaemia, body mass index and serum creatinine concentration. Amongst men with the lowest 25(OH)D quartile of values compared with the highest quartile, the adjusted odds ratio of having an AAA increased in a graded fashion from 1.23 (95% confidence interval (CI) 0.87-1.73) for AAA ≥ 30 mm to 5.42 (95% CI 1.85-15.88) for AAA ≥ 40 mm. Similarly, there was a dose-response relationship between 25(OH)D concentrations and the size of the AAA: every 10-nmol l(-1) decrease in 25(OH)D levels was associated with 0.49 mm (95% CI 0.11-0.87) increase in mean aortic diameter.

CONCLUSIONS

Low vitamin D status is associated with the presence of larger AAA in older men, and there is a graded inverse relationship between 25(OH)D concentrations and AAA diameter. Further research is needed to clarify the mechanisms underlying these associations.

Growth of screen-detected abdominal aortic aneurysms in men: a bayesian analysis

There is considerable interindividual variability in the growth of abdominal aortic aneurysms (AAAs), but an individual's growth observations, risk factors, and biomarkers could potentially be used to tailor surveillance. To assess the potential for tailoring surveillance, this study determined the accuracy of individualized predictions of AAA size at the next surveillance observation. A hierarchical Bayesian model was fitted to a total of 1,732 serial ultrasound measurements from 299 men in whom ultrasound screening identified an AAA. The data were best described by a nonlinear model with a constant first derivative of the AAA growth rate with size. The area under the receiver operating characteristic (ROC) curves for predicting whether an AAA was ≥40 or ≥50 mm at the next observation were 0.922 and 0.979, respectively, and the median root mean squared error was 2.52 mm. These values were nearly identical for models with or without plasma D-dimer effects.CPT: Pharmacometrics & Systems Pharmacology (2012) 1, e12; doi:10.1038/psp.2012.13; advance online publication 24 October 2012.

Statin therapy reduces growth of abdominal aortic aneurysms

BACKGROUND

The aim of this study was to evaluate the influence of statins on the growth of small abdominal aortic aneurysms (AAAs).

METHODS

We retrospectively examined AAA diameter in 211 patients who had undergone serial imaging surveillance.

RESULTS

Patients treated with and without statins were similar regarding age, initial aneurysm size, diagnosis of diabetes and hypertension, and smoking history. Patients receiving statins had a decreased aneurysm growth rate compared with those patients not receiving statins (0.9 mm/y [interquartile range, -1.0 to +1.0] vs 3.2 mm/y [interquartile range, 2.0-4.9], P < 0.0001). This difference in the rate of growth was maintained after adjusting for potential confounding factors.

CONCLUSIONS

To date, this is the one of the largest retrospective studies demonstrating an association between statin use and decreased growth rate of AAA.

First-year results of a national abdominal aortic aneurysm screening programme in a single centre

Background

The UK Multicentre Aneurysm Screening Study (MASS) demonstrated reduced mortality from screening for abdominal aortic aneurysm (AAA). As a result, the National Health Service AAA Screening Programme was introduced in England. This study reports the results from an early-implementation screening centre.

Methods

Men aged 65 years were invited to attend an ultrasound assessment. Data were analysed for 15 months from the onset of the screening programme.

Results

A total of 6091 men aged 65 years were invited between April 2009 and June 2010, of whom 2037 (33·4 per cent) failed to attend. There were 162 self-referrals (median age 71·3 years) so that 4216 men were screened. Of those scanned, 4146 (98·3 per cent) had an aortic diameter of less than 3·0 cm, 65 (1·5 per cent) had an aneurysm measuring 3·0–5·4 cm, and five (0·1 per cent) had an aneurysm with a diameter of 5·5 cm and above. The presence of an aneurysm was more common in those who self-referred than in the invited group (P &lt; 0·001). All 70 screen-detected aneurysms were found in white men.

Conclusion

The prevalence of AAA was lower than expected. This reflects the younger age of this cohort compared with those in published large multicentre studies and the diverse ethnic background of the local population. Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

Implications of attendance patterns in Northern Ireland for abdominal aortic aneurysm screening

INTRODUCTION

Evidence supports the introduction of an abdominal aortic aneurysm (AAA) screening programme. The aims of this study were to estimate future disease patterns and to determine the effect of the proportion attending on the programme's cost-effectiveness.

PATIENTS AND METHODS

The results of the local AAA screening programme were reviewed. Ultrasonic infrarenal aortic diameter of 30 mm was considered aneurysmal. Projected population numbers from the Department of Health and current disease prevalence were used to estimate future number of potential patients. The Multi-centre Aneurysm Screening Study (MASS) Markov model was used to calculate an incremental cost-effectiveness ratio (ICER) and 95% uncertainty intervals (UI), using a 30-year time horizon and 3.5% per annum discount, to determine the effect of attendance.

RESULTS

Men were recruited from August 2004 to May 2010. 13316 were invited for a scan and 5931 (44.5%) attended. 321 AAA were diagnosed, giving a prevalence of 5.4%, while 27 large AAA (0.46%) were repaired. The annual incidence of AAA until 2021 will range from 441 to 526, with an incidence of 40-48 large AAA, with both showing a gradual increase with time. Using this attendance rate, the ICER was calculated at £2350 per life-year gained (95% UI: £1620-£4290), or £3020 per quality-adjusted life-year gained (95% UI: £2080-£5500).

CONCLUSIONS

The prevalence of disease in this local AAA screening was similar to other studies. The low attendance will result in many AAA being missed, but will not impact greatly on the long-term cost-effectiveness.

Diagnosis and monitoring of abdominal aortic aneurysm: current status and future prospects

Abdominal aortic aneurysm (AAA) remains an important cause of morbidity and mortality in elderly men, and prevalence is predicted to increase in parallel with a global aging population. AAA is commonly asymptomatic, and in the absence of routine screening, diagnosis is usually incidental when imaging to assess unrelated medical complaints. In the absence of approved diagnostic and prognostic markers, AAAs are monitored conservatively via medical imaging until aortic diameter approaches 50-55 mm and surgical repair is performed. There is currently significant interest in identifying molecular markers of diagnostic and prognostic value for AAA. Here we outline the current guidelines for AAA management and discuss modern scientific techniques currently employed to identify improved diagnostic and prognostic markers.

Gender Differences in Social Network Size and Satisfaction in Adults in Their 70s

Strong social support is associated with lower mortality and morbidity and better self-rated health in later life. The aim of this study was to compare social network size and satisfaction in men ( N = 2589) and women ( n = 3152), aged 72—78 years. Women reported significantly larger networks (Difference 1.36, 95% CI 0.89, 1.83) than men. However, being separated, divorced or single had a significantly greater impact on men’s social networks (Difference 0.92, 95% CI 0.17, 1.68). Poor mental health and sensory impairments were associated with smaller networks and lower satisfaction with support for both men and women.

Association of an allele on chromosome 9 and abdominal aortic aneurysm

OBJECTIVE

Abdominal aortic aneurysm (AAA) has been recognized as a multi-factorial disease with both genetic and environmental risk factors. A locus residing within non-coding DNA on chromosome 9p21.3 has recently been associated with AAA. To further investigate the significance of this site for AAA, we performed an association study on a large group of 3371 men aged 65-83 years of whom 513 had an AAA.

METHODS

All men were assessed for other risk factors in a uniform way and an ultrasound of the abdominal aorta was performed.

RESULTS

Our findings validated the strong association of the chromosome 9p21.3 SNPs rs10757278 and rs1333049 with AAA and demonstrated the upregulation of LINE-1 elements at the site of AAA.

CONCLUSION

This study confirms a reproducible association between risk alleles on chromosome 9p21.3 and AAA. We also provide preliminary evidence for an association of LINE-1 elements with AAA which will require further investigation.

Association between serum lipoproteins and abdominal aortic aneurysm

The importance of dyslipidemia in the etiology of abdominal aortic aneurysm (AAA) is poorly defined, in part because previous association analyses have often not considered the use of current lipid-modifying medications. Medications targeted at altering the concentrations of circulating lipids have an established role in occlusive atherosclerosis but are of unknown value in the primary prevention of AAA. We examined the association between fasting serum levels of triglycerides low- and high-density lipoprotein and the presence of an AAA in a cohort of 3,327 men aged 65 to 83 years. The analyses were adjusted for established risk factors of AAA and the prescription of lipid-modifying agents using multiple logistic regression analysis. Of the 3,327 men, 1,043 (31%) were receiving lipid-modifying therapy at the fasting lipid measurement. The lipid-modifying therapy was statins in most cases (n = 1,023). The serum high-density lipoprotein concentrations were lower in patients with AAAs. The serum high-density lipoprotein concentration was independently associated with a reduced risk of having an AAA in men not receiving current lipid-modifying therapy (odds ratio 0.72, 95% confidence interval 0.56 to 0.93 per 0.4-mM increase) and in the total cohort (odds ratio 0.76, 95% confidence interval 0.63 to 0.91 per 0.4-mM increase, adjusted for lipid-modifying therapy). The concentrations of low-density lipoprotein and triglycerides were not associated with the presence of AAAs. In conclusion, high-density lipoprotein appeared to be the most important lipid in predicting the risk of AAA development, with potential value as a therapeutic target. Current cardiovascular strategies aimed at lowering low-density lipoprotein might not have any effect on the prevention of AAAs.

The PACE study: a randomised clinical trial of cognitive activity (CA) for older adults with mild cognitive impairment (MCI)

BACKGROUND

Research evidence from observational studies suggests that cognitive activity reduces the risk of cognitive impairment in later life as well as the rate of cognitive decline of people with dementia. The Promoting Healthy Ageing with Cognitive Exercise (PACE) study has been designed to determine whether a cognitive activity intervention decreases the rate of cognitive decline amongst older adults with mild cognitive impairment (MCI).

METHODS/DESIGN

The study will recruit 160 community-dwelling men and women aged 65 years of age or over with mild cognitive impairment (MCI). Participants will be randomly allocated to two treatment groups: non-specific education and cognitive activity. The intervention will consist of ten 90-minute sessions delivered twice per week over a period of five weeks. The primary outcome measure of the study is the change from baseline in the total score on the Cambridge Cognitive Score (CAMCOG). Secondary outcomes of interest include changes in memory, attention, executive functions, mood and quality of life. Primary endpoints will be collected 12, 52 and 104 weeks after the baseline assessment.

DISCUSSION

The proposed project will produce the best available evidence on the merits of increased cognitive activity as a strategy to prevent cognitive decline among older adults with MCI. We anticipate that the results of this study will have implications for the development of evidence-based preventive strategies to reduce the rate of cognitive decline amongst older people at risk of dementia.

TRIAL REGISTRATION

ACTRN12608000556347.

Diabetes and the abdominal aortic aneurysm

OBJECTIVE

The aim of this review is to delineate the association between abdominal aortic aneurysms (AAAs) and diabetes mellitus. Mechanisms for the underlying association are then discussed.

METHODS

A systematic review of the English-language literature using PubMed, EMBASE and Cochrane databases was undertaken up to September 2009. Studies reporting appropriate prevalence data were identified and a meta-analysis performed.

RESULTS

Eleven studies were identified. The prevalence of diabetes mellitus in studied patients with AAA ranged from 6% to 14%. The prevalence of diabetes in control patients without AAA ranged from 17% to 36%. Pooled analysis suggested a reduced rate of diabetes amongst people with AAA compared to those without (OR 0.65, 0.60-0.70, p<0.001).

CONCLUSIONS

Studies so far suggest a protective role for diabetes on the development of AAA. Further research is required to demarcate the underlying mechanisms for this possible association.

Apolipoprotein E genotype is associated with serum C-reactive protein but not abdominal aortic aneurysm

OBJECTIVE

Apolipoprotein E (ApoE) genotype has been associated with systemic inflammation and athero-thrombosis however the association with abdominal aortic aneurysm (AAA) has not been previously examined. We assessed the association between ApoE genotype with AAA presence and growth, and serum C-reactive protein (CRP).

METHODS

Serum concentrations of CRP (in 1358 men) and 6 single nucleotide polymorphisms (SNPs) for ApoE (in 1711 men) were examined in subjects from the Health In Men Study. 640 men with small AAAs were followed by ultrasound surveillance for a mean of 4.1 years.

RESULTS

There was no association between ApoE genotype and AAA presence. Men heterozygote for the ApoE p.Arg176Cys polymorphism had slower AAA growth, odds ratio for AAA progression> or =median 0.41, 95% confidence intervals 0.21-0.80, p=0.01. Men heterozygote for the ApoE g.50093756A>G polymorphism had slightly more rapid AAA growth, odds ratio for AAA progression> or =median 1.48, 95% confidence intervals 1.02-2.14, p=0.04. None of the ApoE SNPs were associated with AAA growth however taking into account multiple testing. Two SNPs in ApoE were associated with serum CRP under a co-dominant model, ApoE p.Cys130Arg (SNP ID rs429358), p=0.00003 and ApoE g.50114786A>G (SNP ID rs4420638), p=0.00013. Adjusting for other risk factors plus serum creatinine the varepsilon4 allele was associated with lower serum CRP under a dominant model, coefficient 0.089, p=0.002.

CONCLUSION

We found no consistent association between ApoE genotype and AAA. We confirmed an association between ApoE genotype and serum CRP.

A genetic polymorphism in transforming growth factor beta receptor-2 is associated with serum osteopontin

Osteopontin (OPN) is a secreted glycoprotein demonstrated to play an important role in inflammation. Transforming growth factor beta and a related signalling pathway have been implicated in control of OPN secretion. We examined the relationship between transforming growth factor beta receptor-1 and -2 (TGFBR1 and 2) single nucleotide polymorphisms (SNP) and serum OPN in 296 men from the Health in Men Study. Serum concentrations of OPN and 58 SNPs for TGFBR1 and 2 were assessed. One SNP in TGFBR2 was associated with serum OPN (TGFBR2 g.20690C>T, SNP ID rs4522809, P = 0.0007) after adjusting for multiple testing. This study suggests that polymorphism in TGFBR2 are associated with altered secretion of OPN, supporting a role for transforming growth factor beta in OPN production.