Genome-wide meta-analysis of variant-by-diuretic interactions as modulators of lipid traits in persons of European and African ancestry.

Hypertension (HTN) is a significant risk factor for cardiovascular morbidity and mortality. Metabolic abnormalities, including adverse cholesterol and triglycerides (TG) profiles, are frequent comorbid findings with HTN and contribute to cardiovascular disease. Diuretics, which are used to treat HTN and heart failure, have been associated with worsening of fasting lipid concentrations. Genome-wide meta-analyses with 39,710 European-ancestry (EA) individuals and 9925 African-ancestry (AA) individuals were performed to identify genetic variants that modify the effect of loop or thiazide diuretic use on blood lipid concentrations. Both longitudinal and cross sectional data were used to compute cohort-specific interaction results, which were then combined through meta-analysis in each ancestry. These ancestry-specific results were further combined through trans-ancestry meta-analysis. Analysis of EA data identified two genome-wide significant (p < 5 × 10-8) loci with single nucleotide variant (SNV)-loop diuretic interaction on TG concentrations (including COL11A1). Analysis of AA data identified one genome-wide significant locus adjacent to BMP2 with SNV-loop diuretic interaction on TG concentrations. Trans-ancestry analysis strengthened evidence of association for SNV-loop diuretic interaction at two loci (KIAA1217 and BAALC). There were few significant SNV-thiazide diuretic interaction associations on TG concentrations and for either diuretic on cholesterol concentrations. Several promising loci were identified that may implicate biologic pathways that contribute to adverse metabolic side effects from diuretic therapy.

Association of complement receptor 1 gene polymorphisms with cognitive function.

Previous evidence suggest involvement of the complement receptor 1 (CR1) in development of Alzheimer's disease. We investigated the association of CR1 gene polymorphisms with cognitive function in older subjects. Single nucleotide polymorphisms (SNPs) within the CR1 region on chromosome 1 ( n = 73) were assessed in 5,244 participants in the PROspective Study of Pravastatin in the Elderly at Risk (51.9% female, mean age 75.3 yr). Linear regression, adjusted for age, sex, country, and use of pravastatin, was used to assess the association between the SNPs and cognitive function. All 73 SNPs within the genomic region of the CR1 gene on chromosome 1 were extracted. Eighteen were independent, according to a relatively stringent R2 threshold of >0.8 with LDlink. Twelve of the 18 investigated CR1 SNPs were significantly associated with a decline in cognitive function (all P < 0.05). These data indicate that genetic variation within the CR1 gene is associated not only with Alzheimer's disease, but also with general cognitive function during late life.

Large-scale pharmacogenomic study of sulfonylureas and the QT, JT and QRS intervals: CHARGE Pharmacogenomics Working Group.

Sulfonylureas, a commonly used class of medication used to treat type 2 diabetes, have been associated with an increased risk of cardiovascular disease. Their effects on QT interval duration and related electrocardiographic phenotypes are potential mechanisms for this adverse effect. In 11 ethnically diverse cohorts that included 71 857 European, African-American and Hispanic/Latino ancestry individuals with repeated measures of medication use and electrocardiogram (ECG) measurements, we conducted a pharmacogenomic genome-wide association study of sulfonylurea use and three ECG phenotypes: QT, JT and QRS intervals. In ancestry-specific meta-analyses, eight novel pharmacogenomic loci met the threshold for genome-wide significance (P<5 × 10-8), and a pharmacokinetic variant in CYP2C9 (rs1057910) that has been associated with sulfonylurea-related treatment effects and other adverse drug reactions in previous studies was replicated. Additional research is needed to replicate the novel findings and to understand their biological basis.

Study protocol: a randomised controlled trial on the clinical effects of levothyroxine treatment for subclinical hypothyroidism in people aged 80 years and over.

BACKGROUND: Subclinical hypothyroidism is common in older people and its contribution to health and disease needs to be elucidated further. Observational and clinical trial data on the clinical effects of subclinical hypothyroidism in persons aged 80 years and over is inconclusive, with some studies suggesting harm and some suggesting benefits, translating into equipoise whether levothyroxine therapy provides clinical benefits. This manuscript describes the study protocol for the Institute for Evidence-Based Medicine in Old Age (IEMO) 80-plus thyroid trial to generate the necessary evidence base. METHODS: The IEMO 80-plus thyroid trial was explicitly designed as an ancillary experiment to the Thyroid hormone Replacement for Untreated older adults with Subclinical hypothyroidism randomised placebo controlled Trial (TRUST) with a near identical protocol and shared research infrastructure. Outcomes will be presented separately for the IEMO and TRUST 80-plus groups, as well as a pre-planned combined analysis of the 145 participants included in the IEMO trial and the 146 participants from the TRUST thyroid trial aged 80 years and over. The IEMO 80-plus thyroid trial is a multi-centre randomised double-blind placebo-controlled parallel group trial of levothyroxine treatment in community-dwelling participants aged 80 years and over with persistent subclinical hypothyroidism (TSH ≥4.6 and ≤ 19.9 mU/L and fT4 within laboratory reference ranges). Participants are randomised to levothyroxine 25 or 50 micrograms daily or matching placebo with dose titrations according to TSH levels, for a minimum follow-up of one and a maximum of three years. Primary study endpoints: hypothyroid physical symptoms and tiredness on the thyroid-related quality of life patient-reported outcome (ThyPRO) at one year. Secondary endpoints: generic quality of life, executive cognitive function, handgrip strength, functional ability, blood pressure, weight, body mass index, and mortality. Adverse events will be recorded with specific interest on cardiovascular endpoints such as atrial fibrillation and heart failure. DISCUSSION: The combined analysis of participants in the IEMO 80-plus thyroid trial with the participants aged over 80 in the TRUST trial will provide the largest experimental evidence base on multimodal effects of levothyroxine treatment in 80-plus persons to date. TRIAL REGISTRATION: Nederlands (Dutch) Trial Register: NTR3851 (12-02-2013), EudraCT: 2012-004160-22 (17-02-2013), ABR-41259.058.13 (12-02-2013).

Non-response to (statin) therapy: the importance of distinguishing non-responders from non-adherers in pharmacogenetic studies.

PURPOSE: In pharmacogenetic research, genetic variation in non-responders and high responders is compared with the aim to identify the genetic loci responsible for this variation in response. However, an important question is whether the non-responders are truly biologically non-responsive or actually non-adherent? Therefore, the aim of this study was to describe, within the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER), characteristics of both non-responders and high responders of statin treatment in order to possibly discriminate non-responders from non-adherers. METHODS: Baseline characteristics of non-responders to statin therapy (≤10 % LDL-C reduction) were compared with those of high responders (>40 % LDL-C reduction) through a linear regression analysis. In addition, pharmacogenetic candidate gene analysis was performed to show the effect of excluding non-responders from the analysis. RESULTS: Non-responders to statin therapy were younger (p = 0.001), more often smoked (p < 0.001), had a higher alcohol consumption (p < 0.001), had lower LDL cholesterol levels (p < 0.001), had a lower prevalence of hypertension (p < 0.001), and had lower cognitive function (p = 0.035) compared to subjects who highly responded to pravastatin treatment. Moreover, excluding non-responders from pharmacogenetic studies yielded more robust results, as standard errors decreased. CONCLUSION: Our results suggest that non-responders to statin therapy are more likely to actually be non-adherers, since they have more characteristics that are viewed as indicators of high self-perceived health and low disease awareness, possibly making the subjects less adherent to study medication. We suggest that in pharmacogenetic research, extreme non-responders should be excluded to overcome the problem that non-adherence is investigated instead of non-responsiveness.

Drug-gene interactions and the search for missing heritability: a cross-sectional pharmacogenomics study of the QT interval.

Variability in response to drug use is common and heritable, suggesting that genome-wide pharmacogenomics studies may help explain the 'missing heritability' of complex traits. Here, we describe four independent analyses in 33 781 participants of European ancestry from 10 cohorts that were designed to identify genetic variants modifying the effects of drugs on QT interval duration (QT). Each analysis cross-sectionally examined four therapeutic classes: thiazide diuretics (prevalence of use=13.0%), tri/tetracyclic antidepressants (2.6%), sulfonylurea hypoglycemic agents (2.9%) and QT-prolonging drugs as classified by the University of Arizona Center for Education and Research on Therapeutics (4.4%). Drug-gene interactions were estimated using covariable-adjusted linear regression and results were combined with fixed-effects meta-analysis. Although drug-single-nucleotide polymorphism (SNP) interactions were biologically plausible and variables were well-measured, findings from the four cross-sectional meta-analyses were null (Pinteraction>5.0 × 10(-8)). Simulations suggested that additional efforts, including longitudinal modeling to increase statistical power, are likely needed to identify potentially important pharmacogenomic effects.

Circulating interleukin-6 concentration and cognitive decline in old age: the PROSPER study.

BACKGROUND: Inflammation is involved in the pathogenesis of cardiovascular disease and cognitive decline. Interleukin-6 (IL-6) has a role in cardiovascular disease, but the association of IL-6 concentration and the functional IL-6 -174 polymorphism with cognitive decline has not been demonstrated unequivocally. The objective of this study was to investigate the associations between both high concentration of IL-6 and the -174 promoter polymorphism, and increased cognitive decline in old age. METHODS: Over 5000 participants of the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER) with a mean age of 75 years and a history of cardiovascular disease or its risk factors were included in this study. We determined baseline concentrations of IL-6 and genotype of the IL-6 -174 polymorphism, of which the C allele was previously shown to be associated with higher circulating concentrations of IL-6. A cognitive test battery was administered at baseline and repeatedly during follow-up (mean 39 months). RESULTS: In the cross-sectional analysis of 5653 participants, higher IL-6 concentration was associated with worse executive cognitive function (P < 0.001), independent of cardiovascular disease status and risk factors. No association was found between IL-6 concentration and memory function (P > 0.14). In the prospective analysis, higher IL-6 concentration was associated with an increased rate of cognitive decline in both executive function (P = 0.002) and memory function (P = 0.002), again independent of cardiovascular disease status and risk factors. Although not associated with IL-6 concentrations, the IL-6 -174 CC genotype was associated with worse performance on the Stroop test (P = 0.045). CONCLUSIONS: Higher circulating levels of IL-6 were associated with worse cognitive function and steeper cognitive decline and provide preliminary genetic evidence for a potential causal association. The findings support the importance of the need for further investigation of the IL-6 pathway in cognitive decline.

The estimation of body height from ulna length in healthy adults from different ethnic groups.

BACKGROUND: Assessments of nutritional status frequently incorporate a measure of height to evaluate a person's relative thinness or fatness. Because height is often difficult to quantify, it may be predicted from alternative anthropometric measurements, including ulna length. Little information is available about the accuracy of these predictions in an ethnically diverse population. The present study aimed to evaluate published equations for predicting height from ulna length in adults from different ethnic groups. METHODS: Ulna length and standing height were measured in a gender-stratified sample of 60 Asian, 69 Black and 65 White healthy volunteers, aged 21-65 years. Height was predicted from ulna length using the Malnutrition Universal Screening Tool (MUST) equations and compared against the measured values. Linear regression analysis was used to develop equations to estimate height from ulna length and to explore the relationship between height and ulna length in subgroups. RESULTS: The mean (SD) age for Asian, Black and White in men was 31.7 (11.0), 32.0 (10.3) and 38.6 (12.5) years and in women was 26.2 (5.4), 32.6 (8.9) and 35.7 (11.7); the mean (SD) height in men was 170.9 (5.2), 178.1 (7.3) and 176.3 (7.7) cm and in women was 157.7 (4.7), 164.0 (5.9) and 163.7 (6.2) cm. Ulna length and measured height were significantly correlated among all subgroups, except Asian women (r=0.11, P=0.57). The mean (SD) difference between predicted and measured height showed significant overestimates for Asian and Black men [4.0 (4.8) and 6.7 (5.3) cm] and Asian and Black women [6.4 (4.9) and 4.4 (4.9) cm] but not for White men and women. CONCLUSIONS: The MUST equations for predicting height from ulna length in healthy adults should be used with some caution among ethnically diverse populations, particularly in Asian women.

The kidney, subclinical thyroid disease and cardiovascular outcomes in older patients.

OBJECTIVE: Thyroid hormones have been implicated to play a role in cardiovascular disease, along with studies linking thyroid hormone to kidney function. The aim of this study is to investigate whether kidney function modifies the association of subclinical thyroid dysfunction and the risk of cardiovascular outcomes. METHODS: In total, 5804 patients were included in the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER). For the current analysis, 426 were excluded because of overt thyroid disease at baseline or 6 months, 266 because of inconsistent thyroid function at baseline and 6 months, 294 because of medication use that could influence thyroid function, and 16 because of missing kidney or thyroid values. Participants with normal fT4 were classified, based on TSH both at inclusion and 6 months, into three groups: subclinical hypothyroidism (TSH >4.5 mIU/L); euthyroidism (TSH = 0.45-4.5 mIU/L); and subclinical hyperthyroidism (TSH <0.45 mIU/L). Strata of kidney function were made based on estimated glomerular filtration rate into three clinically relevant groups: <45, 45-60, and >60 mL/min/1.73 m2. The primary endpoint consists of death from coronary heart disease, non-fatal myocardial infarction and (non)fatal stroke. RESULTS: Mean age was 75.3 years, and 49.0% patients were male. Mean follow-up was 3.2 years. Of all participants, 109 subjects (2.2%) had subclinical hypothyroidism, 4573 (94.0%) had euthyroidism, and 182 (3.7%) subclinical hyperthyroidism. For patients with subclinical hypothyroidism, euthyroidism, and subclinical hyperthyroidism, primary outcome occurred in 9 (8.3%), 712 (15.6%), and 23 (12.6%) patients, respectively. No statistically significant relationship was found between subclinical thyroid dysfunction and primary endpoint with adjusted hazard ratios of 0.51 (0.24-1.07) comparing subclinical hyperthyroidism and 0.90 (0.58-1.39) comparing subclinical hypothyroidism with euthyroidism. Neither was this relationship present in any of the strata of kidney function, nor did kidney function interact with subclinical thyroid dysfunction in the association with primary endpoint (P interaction = 0.602 for subclinical hyperthyroidism and 0.388 for subclinical hypothyroidism). CONCLUSIONS: In this secondary analysis from PROSPER, we found no evidence that the potential association between thyroid hormones and cardiovascular disease is modified by kidney function in older patients with subclinical thyroid dysfunction.

Are elevated circulating intercellular adhesion molecule 1 levels more strongly predictive of diabetes than vascular risk? Outcome of a prospective study in the elderly.

AIMS/HYPOTHESIS: The aim of this prospective study was to determine whether circulating intercellular adhesion molecule (ICAM) 1, as a potential surrogate of 'endothelial activation', is more strongly associated with risk of vascular events than with incident diabetes. METHODS: We related baseline ICAM-1 levels to vascular events (866 CHD and stroke events in 5,685 participants) and incident diabetes (292 in 4,945 without baseline diabetes) in the elderly over 3.2 years of follow-up. RESULTS: ICAM-1 levels correlated positively with triacylglycerol but negatively with LDL- and HDL-cholesterol. ICAM-1 levels were higher in those who developed diabetes (388.6 +/- 1.42 vs 369.4 +/- 1.39 ng/ml [mean+/-SD], p = 0.011) and remained independently associated with new-onset diabetes (HR 1.84, 95% CI 1.26-2.69, p = 0.0015 per unit increase in log[ICAM-1] after adjusting for classical risk factors and C-reactive protein). By contrast, ICAM-1 levels were not significantly (p = 0.40) elevated in those who had an incident vascular event compared with those who remained event-free, and corresponding adjusted risk associations were null (HR 0.98, 95% CI 0.80-1.22, p = 0.89) in analyses adjusted for other risk factors. CONCLUSIONS/INTERPRETATION: We show that elevated ICAM-1 levels are associated with risk of incident diabetes in the elderly at risk, despite no association with incident cardiovascular disease risk. We suggest that perturbations in circulating ICAM-1 levels are aligned more towards diabetes risk.

Genetic variation in the interleukin-1 beta-converting enzyme associates with cognitive function. The PROSPER study.

Inflammation is thought to play an important role in the development of cognitive decline and dementia in old age. The interleukin-1 signalling pathway may play a prominent role in this process. The gene encoding for interleukin-1 beta-converting enzyme (ICE) is likely to influence IL-1 beta levels. Inhibition of ICE decreases the age-related increase in IL-1 beta levels and may therefore improve memory function. We assessed whether genetic variation in the ICE gene associates with cognitive function in an elderly population. All 5804 participants of the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) were genotyped for the 10643GC, 9323GA, 8996AG and 5352GA polymorphisms in the ICE gene. Cross-sectional associations between the polymorphisms and cognitive function were assessed with linear regression. Longitudinal associations between polymorphisms, haplotypes and cognitive function were assessed with linear mixed models. All associations were adjusted for sex, age, education, country, treatment with pravastatin and version of test where appropriate. Subjects carrying the variants 10643C and 5352A allele had significantly lower IL-1 beta production levels (P < 0.01). Furthermore, we demonstrated that homozygous carriers of the 10643C and the 5352A allele performed better on all executive function tests at baseline and during follow-up compared to homozygous carriers of the wild-type allele (all P < 0.02). The haplotype with two variants present (10643C and 5352A) was associated with better executive function (all P < 0.02) compared to the reference haplotype without variants. For memory function the same trend was observed, although not significant. Genetic variation in the ICE gene is associated with better performance on cognitive function and lower IL-1 beta production levels. This suggests that low levels of IL-1 beta are protective for memory and learning deficits. Inhibition of ICE may therefore be an important therapeutic target for maintaining cognitive function in old age.

An 8- to 10-year review of the Rotaglide total knee replacement.

Mobile-bearing knee arthroplasty (MBKA) is an alternative to fixed-bearing knee arthroplasty. This was a retrospective study of the Rotaglide Total Knee System. We present the results of the monitoring of 77 patients (85 knees) with a median duration to failure or end of follow up of 8.5 years (range 0.4 to 10.1 years). Patients were clinically and radiologically assessed at dedicated follow up clinics. The Hospital for Special Surgery (HSS) and Knee Society Score (KSS) systems were used to describe the clinical and radiological findings. The prosthesis had an estimated survival probability of 93.5% (standard error 3.4%) at 9 years. It is associated with good rates of patient satisfaction and high scores on the HSS and KSS systems. No knees were revised for aseptic loosening. This knee replacement has a survival rate equivalent to other prostheses. It is a safe and reliable prosthesis associated with good clinical outcome.

Lymphotoxin-alpha C804A polymorphism is a risk factor for stroke. The PROSPER study.

Inflammation plays a prominent role in the development of atherosclerosis, which is the most important risk factor for vascular events. Lymphotoxin-alpha (LTA) is a pro-inflammatory cytokine and is found to be expressed in atherosclerotic lesions. We investigated the association between the C804A polymorphism within the LTA gene and coronary and cerebrovascular events in 5804 participants of the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER). The primary endpoint was the combined endpoint of death from coronary heart disease, non-fatal myocardial infarction, and clinical stroke. Secondary endpoints were the coronary and cerebrovascular components separately. All associations were assessed with a Cox-proportional hazards model adjusted for sex, age, pravastatin use, and country. Our overall analysis showed a significant association between the C804A polymorphism and the primary endpoint (p = 0.03). After stratification for gender, this association was found only in males. Furthermore, we found that the association between the C804A polymorphism and the primary endpoint was mainly attributable to clinical strokes (p = 0.02). The C804A polymorphism in the LTA gene associates with clinical stroke, especially in men. But further research is warranted to confirm our results.

Genetic variation in the interleukin-10 gene promoter and risk of coronary and cerebrovascular events: the PROSPER study.

Proinflammatory cytokines, like interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), are implicated in the development of atherosclerosis. The role of anti-inflammatory cytokines, like IL-10, is largely unknown. We investigated the association of four single nucleotide polymorphisms (SNPs) in the promoter region of the IL-10 gene (4259AG, -1082GA, -592CA, and -2849GA), with coronary and cerebrovascular disease in participants of the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) trial. All associations were assessed with Cox proportional hazards models adjusted for sex, age, pravastatin use, and country. Haplotype analysis of the four SNPs showed a significant association between haplotype 4 (containing the -592A variant allele) and risk of coronary events (P = 0.019). Moreover, analysis of separate SNPs found a significant association between -2849AA carriers with incident stroke (HR (95%CI) 1.50 (1.04-2.17), P value = 0.02). Our study suggests that not only proinflammatory processes contribute to atherosclerosis, but that also anti-inflammatory cytokines may play an important role.

Ki-67 expression in melanoma. A potential method of risk assessment for the patient with a positive sentinel node.

Melanoma patients with a positive sentinel node biopsy generally proceed to regional lymph node dissection, though ultimately only around 20% have evidence of tumour in their "non-sentinel" nodes. A means to identify patients at high risk of non-sentinel node involvement could potentially spare a large number of patients a procedure with significant morbidity. The proliferation marker Ki-67 has been associated with tumour progression in primary melanoma but has not been extensively studied in metastases. The study aims to investigate Ki-67 in primary melanoma and lymph node metastases and investigate any relationship with disease progression. Tissue Arrays of primary melanoma (n=79) and lymph node metastases (n=92) were constructed from paraffin embedded tissue and Ki-67 expression examined by immunohistochemistry. Staining positivity and intensity were assessed and correlated with standard staging criteria and clinical outcome. High Ki-67 expression was associated with both Breslow thickness (chi(2)=8.54, p=0.035) and presence of ulceration (Fisher's Exact test p=0.003) in primary melanoma. In lymph node metastases high Ki-67 expression correlated with Nodal (N) Stage (chi(2)=8.193, p=0.0 17). High Ki-67 expression is associated with melanoma progression and multiple lymph node involvement. This might potentially form the basis of a risk analysis for patients with positive sentinel nodes.

Dementia in subjects with atrial fibrillation: hemostatic function and the role of anticoagulation.

BACKGROUND: Atrial fibrillation (AF) is associated with cognitive impairment and dementia, perhaps through encouraging a prothrombotic state and cardioembolism. OBJECTIVES: We wished to test the hypotheses that hemostatic function is altered in subjects with AF who develop dementia, and that long-term warfarin anticoagulation is protective against this complication. PATIENTS AND METHODS: Recruitment was from an observational cohort study of AF. Baseline assessment included measurement of plasma fibrinogen, fibrin D-dimer, prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complexes (TAT), von Willebrand factor and tissue plasminogen activator. We assessed cognitive function after 3 years' follow-up using the 13-item modified Telephone Interview for Cognitive Status (TICSm) and the short form of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). RESULTS: Of the 218 subjects assessed, 145 (66%) were prescribed warfarin. Forty-nine (22%) met TICSm/IQCODE criteria for dementia. D-dimer, F1+2 and TAT levels were higher in AF subjects with dementia compared with those without (medians 81 vs. 60 ng mL(-1), P = 0.008; 0.76 vs. 0.49 nmol L(-1), P = 0.006; and 1.78 vs. 1.44 microg L(-1), P = 0.003, respectively). These associations became of borderline statistical significance following adjustment for age. Logistic regression showed a trend towards warfarin use being independently associated with reduced prevalence of dementia (odds ratio 0.52, P = 0.08). CONCLUSIONS: We found evidence of increased thrombin generation and fibrin turnover in subjects with AF and dementia compared with those without dementia. Long-term warfarin use may be protective against the development of dementia in subjects with AF.

The design of a prospective study of Pravastatin in the Elderly at Risk (PROSPER). PROSPER Study Group. PROspective Study of Pravastatin in the Elderly at Risk.

The PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) is a randomized, double-blind, placebo-controlled trial designed to test the hypothesis that treatment with pravastatin will diminish risk of subsequent major vascular events in a cohort of men and women (70 to 82 years old) with preexisting vascular disease or significant risk of developing this condition. Five thousand eight hundred four men and women in addition to receiving advice on diet and smoking, have been randomized equally to treatment with 40 mg pravastatin/day or matching placebo in 3 centers (Cork, Ireland, Glasgow, Scotland, and Leiden, The Netherlands). Following an average 3.5-year intervention period, a primary assessment will be made of the influence of this therapy on major vascular events (a combination of coronary heart disease, death, nonfatal myocardial infarction, and fatal and nonfatal stroke). A number of additional analyses will also be conducted on the individual components of the primary end point, on men, on women, and on subjects with and without previous evidence of vascular disease. Finally, an assessment will be made of the effects of treatment on cognitive function, disability, hospitalization or institutionalization, vascular mortality, and all-cause mortality.

Use of plasma ferritin concentration to diagnose iron deficiency in elderly patients.

AIMS: To determine a concentration of ferritin below which the possibility of iron deficiency should be considered in elderly patients. METHODS: Consecutive new referrals to a geriatric unit (n = 472) were studied prospectively. Full blood count, ferritin, serum vitamin B12 and red cell folate were measured for all patients. A blood film was assessed independently by three haematologists for features of iron deficiency. For those with ferritin of 12-45 ng/ml, bone marrow aspirates were performed and examined for the presence of stainable iron. When possible, a trial of oral iron was given to those with ferritin of < or = 45 ng/ml and response was determined by re-measurement of full blood count and ferritin after a minimum of three weeks of treatment. RESULTS: Bone marrow examination was performed in 32 patients with ferritin of 12-45 ng/ml, of whom 27 (84%) had absent stainable iron, suggesting that most elderly patients with ferritin in this range have iron deficiency. Compared with those with ferritin of 100-299 ng/ml, in whom iron stores were presumed to be normal, patients with ferritin of 12-45 ng/ml had a significantly lower mean haemoglobin and mean red blood cell volume. Furthermore, patients with ferritin up to 75 ng/ml had a significantly higher mean red cell distribution width, and were more likely to have an iron deficient blood film. CONCLUSION: Iron deficient erythropoiesis can occur in elderly patients with ferritin up to 75 ng/ml. This is much higher than the lower limit of the "normal" range usually quoted for younger subjects; this difference should be taken into account when ferritin concentrations are interpreted in elderly patients.

Acute cerebral infarction. Optimal management in older patients.

The optimal management of acute cerebral infarction requires consideration of the diagnosis, aetiology, identification of problems, general and specific aspects of care, and prevention of further vascular events. Stroke is a clinical diagnosis but cranial computed tomography (CT) scanning is invaluable to exclude the possibility of cerebral haemorrhage or where the diagnosis is uncertain. Good general care under a specialist multidisciplinary team can reduce mortality and the need for institutional care. Despite promising results from experimental studies, no routine drug therapies have yet shown clinical benefit in acute stroke. Several large trials are currently evaluating anticoagulant, antiplatelet, thrombolytic and neuroprotective agents. Many other proposed therapies have been subject to limited evaluation. Aspirin has a proven role in the prevention of further vascular events after a stroke or transient ischaemic attack. Warfarin, and to a lesser extent aspirin, can prevent recurrent events in patients with nonrheumatic atrial fibrillation. Concerns remain about the safety of warfarin in routine geriatric medical practice. The risk of recurrent stroke in patients with a symptomatic severe carotid artery stenosis is greatly reduced by endarterectomy.

Influenza diagnosis: from dark isolation into the molecular light. West of Scotland Respiratory Virus Study Group.

OBJECTIVES: To compare the conventional virus isolation method for diagnosis of influenza infection with reverse-transcription polymerase chain reaction (RT-PCR) in prospectively collected nose and throat swabs from elderly patients during the winter influenza season. The use of a denaturing buffer as an alternative to viral transport medium (VTM) for submission of combined nose and throat swabs to the laboratory for PCR was then investigated in a second study. METHODS: Virus was cultured in microtitre plates using two different cell lines and detected using monoclonal antibody staining. A multiplex, matrix gene PCR assay was optimized to increase the sensitivity and specificity of detection of influenza A (H3 and H1) and B nucleic acid. RESULTS: The multiplex assay detected all viruses with equal sensitivity to individual assays. In a large, multicentre field study PCR detected twice as many influenza infections compared with virus isolation. No positive culture was missed. PCR has a rapid turn around time (< 36 h) vs. a minimum of 7 days for virus isolation. Greater sensitivity and specificity in the PCR were achieved using a 'hot-start' method. Although the numbers were small, the detection rate using PCR was greater for swabs submitted in denaturing buffer than in VTM. CONCLUSIONS: PCR significantly increased the sensitivity and clinical utility of influenza A (H3 and H1) and B diagnosis. There were a number of advantages in using denaturing buffer for submission of samples, including high sensitivity, rapidity, ease of use and no requirement for the virus to be viable on arrival at the laboratory. Therefore, PCR is a rapid, sensitive and user-friendly alternative for influenza diagnosis. Virus isolation technology should be limited to referral centres for further epidemiological characterization.