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The World Health Organization recommends that all blood donations be screened for transfusion transmissible infections; these data are currently not incorporated into national disease surveillance efforts. We set out to use routinely collected data from blood donors in Blantyre district, Malawi to explore HIV and syphilis prevalence and identify sero-conversions among repeat donors. We conducted a retrospective cohort analysis of blood donation data collected by the Malawi Blood Transfusion Service from 2015 to 2021. All blood donations were routinely screened for HIV and syphilis. We characterized donor demographics as well as screening outcomes, including identifying sero-conversions among repeat donors who previously tested negative on their last donation. A total of 23,280 donations from 5,051 donors were recorded, with a median frequency of donations of 3 (IQR:2-6). Most donors were male (4,294; 85%) and students (3,262; 64.6%). Prevalence of HIV at first donation was 1.0% (52/5,051) and prevalence of syphilis was 1.6% (80/5,051); 52 HIV sero-conversions and 126 syphilis sero-conversions were identified, indicating an incidence rate per 1,000 person-years of 5.9 (95% CI: 4.7, 7.4) and 13.3 (95% CI:11.4, 15.4) respectively. Students had a lower prevalence of HIV and syphilis but higher risk of syphilis seroconversion. While blood donors are generally considered a low-risk population for HIV and syphilis, we were able to identify relatively high rates of undiagnosed HIV and syphilis infections among donors. Routinely collected data from national blood donation services may be used to better understand local HIV and syphilis epidemiology, with the potential to enhance disease surveillance systems. These findings may be used to identify priority prevention areas and populations in Blantyre district that can inform targeted interventions for improved disease prevention, testing and treatment., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Singogo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: In 2017, Blantyre district had the highest adult HIV prevalence in Malawi (17.7%) and lowest viral suppression (60%). In response, the Ministry of Health expanded prevention and treatment services. We assessed whether outreach to social venues could identify individuals with increased HIV acquisition risk or with unsuppressed HIV not currently reached by clinic-based services., Methods: We conducted a cross-sectional bio-behavioral survey in Blantyre, Malawi, from January to March 2022. We visited social venues where people meet new sexual partners and government clinics providing HIV testing or STI screening. Participants aged > 15 years were interviewed, and tested for HIV infection if not on ART. HIV recency tests were performed on those testing positive, and dried blood spots (DBS) was collected to quantify viral load and also to identify acute infection in those with HIV- results., Results: HIV prevalence (18.5% vs 8.3%) and unsuppressed HIV infection (3.9% vs 1.7%) were higher among venue-recruited (n=1802) compared with clinic-recruited participants(n=2313). Among PLHIV at both clinics (n=199) and venues (n=289), 79% were virally suppressed. Few had acute(n=1) or recent infection(n=8). Among women, HIV prevalence was four times higher (38.9% venue vs 8.9% clinic). At clinics, PLHIV reporting visiting venues were less likely to be suppressed (54.6 vs 82.6%). More men at venues than at clinics reported paying for sex (49% vs 30%) or having multiple sex partners in the past 4 weeks (32% vs 16%)., Conclusions: Enhanced venue-based prevention and testing for men and women could reduce treatment lapses, HIV treatment outcomes and reduce onward transmission., Competing Interests: Conflicts of Interest and Source of Funding: The authors declare no competing interest. The study reported in this publication was supported by the MeSH Consortium at UNC Project Malawi and London School of Hygiene & Tropical Medicine-UK, which is funded by the Bill & Melinda Gates Foundation. The content is solely the responsibility of the authors and does not necessarily represent the official views of funders., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Objectives: This study explores perceptions of US Veterans Affairs (VA) and non-VA healthcare providers caring for Veterans with heart failure (HF) regarding Veteran knowledge and motivations for dual use, provider roles in recommending and coordinating dual use, systems barriers and facilitators, and suggestions for improving cross-system care., Methods: Twenty VA and 11 non-VA providers participated in semi-structured interviews, which were analyzed using parallel qualitative content and discourse analysis., Results: VA and non-VA providers described variable HF knowledge and self-management among Veterans, and both groups described the need for improved education addressing medication adherence, self-care, and management of acute symptoms. Both groups described highly limited roles for providers in shaping choices surrounding dual use. VA and non-VA providers had significantly different perceptions regarding the availability, quality, and effectiveness of VA HF services. Multiple non-VA providers expressed frustration with and difficulty in contacting VA providers, accessing records, and making referrals into the VA system. Suggestions for improved care focused on patient education and care coordination., Discussion: Dual healthcare system use for Veterans is increasingly common. Similarities and contrasts in perceptions of VA and non-VA providers are instructive and should be incorporated into future policy and program initiatives.

Background: Chlamydia is a major public health concern, with high economic and social costs. In 2016, there were over 200,000 chlamydia diagnoses made in England. The highest prevalence rates are found among young people. Although annual testing for sexually active young people is recommended, many do not receive testing. General practice is one ideal setting for testing, yet attempts to increase testing in this setting have been disappointing. The Capability, Opportunity, and Motivation Model of Behaviour (COM-B model) may help improve understanding of the underpinnings of chlamydia testing. The aim of this systematic review was to (1) identify barriers and facilitators to chlamydia testing for young people and primary care practitioners in general practice and (2) map facilitators and barriers onto the COM-B model., Methods: Qualitative, quantitative, and mixed methods studies published after 2000 were included. Seven databases were searched to identify peer-reviewed publications which examined barriers and facilitators to chlamydia testing in general practice. The quality of included studies was assessed using the Critical Appraisal Skills Programme. Data (i.e., participant quotations, theme descriptions, and survey results) regarding study design and key findings were extracted. The data was first analysed using thematic analysis, following this, the resultant factors were mapped onto the COM-B model components. All findings are reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines., Results: Four hundred eleven papers were identified; 39 met the inclusion criteria. Barriers and facilitators were identified at the patient (e.g., knowledge), provider (e.g., time constraints), and service level (e.g., practice nurses). Factors were categorised into the subcomponents of the model: physical capability (e.g., practice nurse involvement), psychological capability (e.g.: lack of knowledge), reflective motivation (e.g., beliefs regarding perceived risk), automatic motivation (e.g., embarrassment and shame), physical opportunity (e.g., time constraints), social opportunity (e.g., stigma)., Conclusions: This systematic review provides a synthesis of the literature which acknowledges factors across multiple levels and components. The COM-B model provided the framework for understanding the complexity of chlamydia testing behaviour. While we cannot at this juncture state which component represents the most salient influence on chlamydia testing, across all three levels, multiple barriers and facilitators were identified relating psychological capability and physical and social opportunity. Implementation should focus on (1) normalisation, (2) communication, (3) infection-specific information, and (4) mode of testing. In order to increase chlamydia testing in general practice, a multifaceted theory- and evidence-based approach is needed., Trial Registration: PROSPERO CRD42016041786.

Background: In 2013, Public Health England piloted the '3Cs (chlamydia, contraception, condoms) and HIV (human immunodeficiency virus)' educational intervention in 460 GP surgeries. The educational HIV workshop aimed to improve the ability and confidence of staff to offer HIV testing in line with national guidelines., Aim: To qualitatively assess the impact of an educational workshop on GP staff's attitudes to NICE HIV testing guidelines., Design & Setting: Qualitative interviews with GP staff across England before and after an educational HIV workshop., Method: Thirty-two GP staff (15 before and 17 after educational HIV workshop) participated in interviews exploring their views and current practice of HIV testing. Interview transcripts were thematically analysed and examined, using the components of the theory of planned behaviour (TPB) and normalisation process theory (NPT) as a framework., Results: GPs reported that the educational HIV workshop resulted in increased knowledge of, and confidence to offer, HIV tests based on indicator conditions. However, overall participants felt they needed additional HIV training around clinical care pathways for offering tests, giving positive HIV results, and current treatments and outcomes. Participants did not see a place for point-of-care testing in general practice., Conclusion: Implementation of national HIV guidelines will require multiple educational sessions, especially to implement testing guidelines for indicator conditions in areas of low HIV prevalence. Additional role-play or discussions around scripts suggesting how to offer an HIV test may improve participants' confidence and facilitate increased testing. Healthcare assistants (HCAs) may need specific training to ensure that they are skilled in offering HIV testing within new patient checks., Competing Interests: CAMMcN: CAMMcN writes the PHE primary care guidance around testing for chlamydia and STIs. The other authors declare that no competing interests exist.

Background: Timely diagnosis of human immunodeficiency virus (HIV) enables access to antiretroviral treatment, which reduces mortality, morbidity and further transmission in people living with HIV. In the UK, late diagnosis among black African people persists. Novel methods to enhance HIV testing in this population are needed., Objectives: To develop a self-sampling kit (SSK) intervention to increase HIV testing among black Africans, using existing community and health-care settings (stage 1) and to assess the feasibility for a Phase III evaluation (stage 2)., Design: A two-stage, mixed-methods design. Stage 1 involved a systematic literature review, focus groups and interviews with key stakeholders and black Africans. Data obtained provided the theoretical base for intervention development and operationalisation. Stage 2 was a prospective, non-randomised study of a provider-initiated, HIV SSK distribution intervention targeted at black Africans. The intervention was assessed for cost-effectiveness. A process evaluation explored feasibility, acceptability and fidelity., Setting: Twelve general practices and three community settings in London., Main Outcome Measure: HIV SSK return rate., Results: Stage 1 - the systematic review revealed support for HIV SSKs, but with scant evidence on their use and clinical effectiveness among black Africans. Although the qualitative findings supported SSK distribution in settings already used by black Africans, concerns were raised about the complexity of the SSK and the acceptability of targeting. These findings were used to develop a theoretically informed intervention. Stage 2 - of the 349 eligible people approached, 125 (35.8%) agreed to participate. Data from 119 were included in the analysis; 54.5% (65/119) of those who took a kit returned a sample; 83.1% of tests returned were HIV negative; and 16.9% were not processed, because of insufficient samples. Process evaluation showed the time pressures of the research process to be a significant barrier to feasibility. Other major barriers were difficulties with the SSK itself and ethnic targeting in general practice settings. The convenience and privacy associated with the SSK were described as beneficial aspects, and those who used the kit mostly found the intervention to be acceptable. Research governance delays prevented implementation in Glasgow., Limitations: Owing to the study failing to recruit adequate numbers (the intended sample was 1200 participants), we were unable to evaluate the clinical effectiveness of SSKs in increasing HIV testing in black African people. No samples were reactive, so we were unable to assess pathways to confirmatory testing and linkage to care., Conclusions: Our findings indicate that, although aspects of the intervention were acceptable, ethnic targeting and the SSK itself were problematic, and scale-up of the intervention to a Phase III trial was not feasible. The preliminary economic model suggests that, for the acceptance rate and test return seen in the trial, the SSK is potentially a cost-effective way to identify new infections of HIV., Future Work: Sexual and public health services are increasingly utilising self-sampling technologies. However, alternative, user-friendly SSKs that meet user and provider preferences and UK regulatory requirements are needed, and additional research is required to understand clinical effectiveness and cost-effectiveness for black African communities., Study Registration: This study is registered as PROSPERO CRD42014010698 and Integrated Research Application System project identification 184223., Funding: The National Institute for Health Research Health Technology Assessment programme and the BHA for Equality in Health and Social Care., Competing Interests: Fiona Burns reports grants from the National Institute for Health Research (NIHR) for other projects during the conduct of the study, and personal fees and other from Gilead Sciences Ltd (London, UK), outside the submitted work. Rachael Hunter reports grants from the NIHR Health Technology Assessment (HTA) programme for other projects, during the conduct of the study. Ibidun Fakoya reports a grant from NIHR for another project, during the conduct of the study. Eleni Nastouli reports personal fees from Roche (Burgess Hill, UK), grants from Viiv Healthcare (London, UK), grants from the European Union (H2020) and personal fees from NIHR, outside the submitted work. Lisa McDaid reports grants from the NIHR HTA programme for other projects, during the conduct of the study. Jane Anderson reports grants and personal fees from Gilead Sciences Ltd, and personal fees from ViiV Healthcare, Merck Sharp & Dohme Limited (Hoddesdon, UK), Bristol-Myers Squibb (Uxbridge, UK), Jansen-Cilag Limited (High Wycombe, UK) and AbbVie (Maidenhead, UK), outside the submitted work.

Introduction: Chlamydia is a key health concern with high economic and social costs. There were over 200 000 chlamydia diagnoses made in England in 2015. The burden of chlamydia is greatest among young people where the highest prevalence rates are found. Annual testing for sexually active young people is recommended; however, many of those at risk do not receive testing. General practice has been identified as an ideal setting for testing, yet efforts to increase testing in this setting have not been effective. One theoretical model which may provide insight into the underpinnings of chlamydia testing is the Capability, Opportunity and Motivation Model of Behaviour (COM-B model). The aim of this systematic review is to: (1) identify barriers and facilitators to chlamydia testing for young people in general practice and (2) use a theoretical model to conduct a behavioural analysis of chlamydia testing behaviour., Methods and Analysis: Qualitative, quantitative and mixed methods studies published after 2000 will be included. Seven databases (MEDLINE, PubMed, EMBASE, Informit, PsycInfo, Scopus, Web of Science) will be searched to identify peer-reviewed publications which examined barriers and facilitators to chlamydia testing in general practice. Risk of bias will be assessed using the Critical Appraisal Skills Programme. Data regarding study design and key findings will be extracted. The data will be analysed using thematic analysis and the resultant factors will be mapped onto the COM-B model components. All findings will be reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines., Ethics and Dissemination: Ethical approval is not required. The results will be disseminated via submission for publication to a peer-review journal when complete and for presentation at national and international conferences. The review findings will be used to inform the development of interventions to facilitate effective and efficient chlamydia testing in general practice., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Background: Providing sexual health services in primary care is an essential step towards universal provision. However they are not offered consistently. We conducted a national pilot of an educational intervention to improve staff's skills and confidence to increase chlamydia testing rates and provide condoms with contraceptive information plus HIV testing according to national guidelines, known as 3Cs&HIV. The effectiveness of the pilot on chlamydia testing and diagnosis rates in general practice was evaluated., Methods: The pilot was implemented using a step-wedge design over three phases during 2013 and 2014 in England. The intervention combined educational workshops with posters, testing performance feedback and continuous support. Chlamydia testing and diagnosis rates in participating general practices during the control and intervention periods were compared adjusting for seasonal trends in chlamydia testing and differences in practice size. Intervention effect modification was assessed for the following general practice characteristics: chlamydia testing rate compared to national median, number of general practice staff employed, payment for chlamydia screening, practice urban/rurality classification, and proximity to sexual health clinics., Results: The 460 participating practices conducted 26,021 tests in the control period and 18,797 tests during the intervention period. Intention-to-treat analysis showed no change in the unadjusted median tests and diagnoses per month per practice after receiving training: 2.7 vs 2.7; 0.1 vs 0.1. Multivariable negative binomial regression analysis found no significant change in overall testing or diagnoses post-intervention (incidence rate ratio (IRR) 1.01, 95 % confidence interval (CI) 0.96-1.07, P = 0.72; 0.98 CI 0.84-1.15, P = 0.84, respectively). Stratified analysis showed testing increased significantly in practices where payments were in place prior to the intervention (IRR 2.12 CI 1.41-3.18, P < 0.001) and in practices with 6-15 staff (6-10 GPs IRR 1.35 (1.07-1.71), P = 0.012; 11-15 GPs IRR 1.37 (1.09-1.73), P = 0.007)., Conclusion: This national pilot of short educational training sessions found no overall effect on chlamydia testing in primary care. However, in certain sub-groups chlamydia testing rates increased due to the intervention. This demonstrates the importance of piloting and evaluating any service improvement intervention to assess the impact before widespread implementation, and the need for detailed understanding of local services in order to select effective interventions.

Background: The National Chlamydia Screening Programme performs 1.7 million tests annually among young adults in England. The effect of chlamydia screening on subsequent behavior is unknown. This study examined the self-reported impact of testing on young adults' subsequent health care-seeking and sexual behavior., Methods: We conducted a cross-sectional Web-based anonymous survey using an online panel to recruit 1521 young adults aged 16 to 24 years and resident in England. Survey questions were developed using the theory of planned behavior. Multivariate log-binomial regression was used to identify the variables associated with an impact on subsequent behavior after testing., Results: Most respondents reported that being tested for chlamydia had a positive effect on their subsequent sexual behavior (68.6%; 422/615) or health care-seeking behavior (80.0%; 492/615). In multivariate analysis, being female and having a high level of engagement at last test were both associated with positive impacts on sexual behavior (72.7% [adjusted prevalence ratio {aPR}, 1.19; 95% confidence interval {CI}, 1.07-1.33] and 82.7% [aPR, 1.55; 95% CI, 1.27-1.89], respectively), and health care-seeking behavior (84.4% [aPR, 1.13; 95% Cl, 1.04-1.24] and 86.3% [aPR, 1.23; 95% CI, 1.07-1.41], respectively). Among respondents with minimum level of engagement, 72.4% (76/105) reported an increase in subsequent health care-seeking behavior., Conclusions: Chlamydia testing had a positive impact on young adults' self-reported health care-seeking and sexual behavior. This suggests that chlamydia screening has a wider effect on young adults' sexual health beyond that of treatment alone.

Background: Widespread implementation of palliative care treatment plans could reduce suffering in the last days of life by adopting best practices of traditionally home-based hospice care in inpatient settings., Objective: To evaluate the effectiveness of a multi-modal intervention strategy to improve processes of end-of-life care in inpatient settings., Design: Implementation trial with an intervention staggered across hospitals using a multiple-baseline, stepped wedge design., Participants: Six Veterans Affairs Medical Centers (VAMCs)., Intervention: Staff training was targeted to all hospital providers and focused on identifying actively dying patients and implementing best practices from home-based hospice care, supported with an electronic order set and paper-based educational tools., Main Measures: Several processes of care were identified as quality endpoints for end-of-life care (last 7 days) and abstracted from electronic medical records of veterans who died before or after intervention (n = 6,066). Primary endpoints were proportion with an order for opioid pain medication at time of death, do-not-resuscitate order, location of death, nasogastric tube, intravenous line infusing, and physical restraints. Secondary endpoints were administration of opioids, order/administration of antipsychotics, benzodiazepines, and scopolamine (for death rattle); sublingual administration; advance directives; palliative care consultations; and pastoral care services. Generalized estimating equations were conducted adjusting for longitudinal trends., Key Results: Significant intervention effects were observed for orders for opioid pain medication (OR: 1.39), antipsychotic medications (OR: 1.98), benzodiazepines (OR: 1.39), death rattle medications (OR: 2.77), sublingual administration (OR: 4.12), nasogastric tubes (OR: 0.71), and advance directives (OR: 1.47). Intervention effects were not significant for location of death, do-not-resuscitate orders, intravenous lines, or restraints., Conclusions: This broadly targeted intervention strategy led to modest but statistically significant changes in several processes of care, indicating its potential for widespread dissemination to improve end-of-life care for thousands of patients who die each year in inpatient settings.

Objective: To identify risk factors associated with methicillin-resistant Staphylococcus aureus (MRSA) acquisition in long-term care facility (LTCF) residents., Design: Multicenter, prospective cohort followed over 6 months., Setting: Three Veterans Affairs (VA) LTCFs., Participants: All current and new residents except those with short stay (<2 weeks)., Methods: MRSA carriage was assessed by serial nares cultures and classified into 3 groups: persistent (all cultures positive), intermittent (at least 1 but not all cultures positive), and noncarrier (no cultures positive). MRSA acquisition was defined by an initial negative culture followed by more than 2 positive cultures with no subsequent negative cultures. Epidemiologic data were collected to identify risk factors, and MRSA isolates were typed by pulsed-field gel electrophoresis (PFGE)., Results: Among 412 residents at 3 LTCFs, overall MRSA prevalence was 58%, with similar distributions of carriage at all 3 facilities: 20% persistent, 39% intermittent, 41% noncarriers. Of 254 residents with an initial negative swab, 25 (10%) acquired MRSA over the 6 months; rates were similar at all 3 LTCFs, with no clusters evident. Multivariable analysis demonstrated that receipt of systemic antimicrobials during the study was the only significant risk factor for MRSA acquisition (odds ratio, 7.8 [95% confidence interval, 2.1-28.6]; P = .002). MRSA strains from acquisitions were related by PFGE to those from a roommate in 9/25 (36%) cases; 6 of these 9 roommate sources were persistent carriers., Conclusions: MRSA colonization prevalence was high at 3 separate VA LTCFs. MRSA acquisition was strongly associated with antimicrobial exposure. Roommate sources were often persistent carriers, but transmission from roommates accounted for only approximately one-third of MRSA acquisitions.

Exposure of newborn calves to chronic hypoxia causes pulmonary artery (PA) hypertension and remodeling. Previous studies showed that the redox-sensitive transcription factor, early growth response-1 (Egr-1), is upregulated in the PA of chronically hypoxic calves and regulates cell proliferation. Furthermore, we established in mice a correlation between hypoxic induction of Egr-1 and reduced activity of extracellular superoxide dismutase (EC-SOD), an antioxidant that scavenges extracellular superoxide. We now hypothesize that loss of EC-SOD in chronically hypoxic calves leads to extracellular superoxide-mediated upregulation of Egr-1. To validate our hypothesis and identify the signaling pathways involved, we utilized PA tissue from normoxic and chronically hypoxic calves and cultured calf and human PA smooth muscle cells (PASMC). Total SOD activity was low in the PA tissue, and only the extracellular SOD component decreased with hypoxia. PA tissue of hypoxic calves showed increased oxidative stress and increased Egr-1 mRNA. To mimic the in vivo hypoxia-induced extracellular oxidant imbalance, cultured calf PASMC were treated with xanthine oxidase (XO), which generates extracellular superoxide and hydrogen peroxide. We found that 1) XO increased Egr-1 mRNA and protein, 2) XO induced the phosphorylation of ERK1/2 and, 3) pretreatment with an ERK1/2 inhibitor prevented induction of Egr-1 by XO. siRNA knock-down of EC-SOD in human PASMC also upregulated Egr-1 mRNA and protein, activated ERK1/2, and enhanced SMC proliferation and reduced apoptosis. We conclude that an oxidant/antioxidant imbalance arising from loss of EC-SOD in the PA with chronic hypoxia induces Egr-1 via activation of ERK1/2 and contributes to pulmonary vascular remodeling.

Under the auspices of the Nuclear Receptor Signaling Atlas (NURSA), we have undertaken to evaluate the feasibility of targeting nuclear receptor-coactivator surfaces for new drug discovery. The underlying objective of this approach is to provide the research community with reagents that can be used to modulate the transcriptional activity of nuclear receptors. Using combinatorial peptide phage display, we have been able to develop peptide antagonists that target specific nuclear receptor (NR)-coactivator binding surfaces. It can be appreciated that reagents of this nature will be of use in the study of orphan nuclear receptors for whom classical ligands have not yet been identified. In addition, because the interaction of coactivators with the receptor is an obligate step for NR transcriptional activity, it is anticipated that peptides that block these interactions will enable the definition of the biological and pharmacological significance of individual NR-coactivator interactions. In this report, we describe the use of this approach to develop antagonists of the androgen receptor by targeting its coactivator-binding pocket and their use to study the coactivator-binding surface of this receptor. Based on our findings, we believe that molecules that function by disrupting the androgen receptor-cofactor interactions will have use in the treatment of prostate cancer.

The full-length human androgen receptor with an N-terminal biotin acceptor peptide tag was overexpressed in Spodoptera frugiperda cells in the presence of 1 microM dihydrotestosterone. Site-specific biotinylation of BAP was achieved in vivo by co-expression of E. coli biotin holoenzyme synthetase. The androgen receptor was purified by single-step affinity chromatography using Streptavidin Mutein Matrix under native conditions. The resultant protein was active, stable, 95% homogeneous, and we obtained sufficient yield for use in functional and structural studies.

Determining the cardioprotective effects of aspirin (acetylsalicylic acid) remains a focus for both basic science and clinical investigation. Although other contributors are probably present, the favorable prostacyclin-to-thromboxane ratio induced by low-dose aspirin appears beneficial for reducing cardiovascular mortality associated with unstable angina and myocardial infarction. The precise dosage, frequency and timing of aspirin's administration to reduce the incidence of vaso-occlusive events remains to be determined. This article reviews aspirin's mechanism of action and use for the prevention of myocardial infarction.