Current approaches to the pharmacological management of metastatic breast cancer in older women.

INTRODUCTION: A substantial majority of patients diagnosed with metastatic breast cancer consists of individuals 65-year-old or above. Emerging treatment approaches, which utilize genomics-guided therapy and innovative biomarkers, are currently in development. Given the numerous choices in the metastatic context, it is necessary to adopt a personalized approach to decision-making for these patients. AREAS COVERED: The authors provide a comprehensive analysis of the existing literature on the use of systemic anticancer treatments in older women, specifically those aged 65 and above, who have metastatic breast cancer, focusing on the reported effectiveness and adverse effects of these treatments in this population. EXPERT OPINION: The evidence to treat older patients with metastatic breast cancer primarily relies on subgroup analyses, whose interpretation should be approached with caution. In several clinical trials subgroup analysis, it has been observed that this population seem to have comparable benefits and toxicities to younger patients, but real-world data have showed older women exhibit worse rates of survival compared to younger women. Multiple factors are likely involved in this, but we postulate this is related to lower rates of guideline concordant, and factors such as comorbidity, lack of social supports, malnutrition, and geriatric factors like frailty and/or vulnerability. This underscores the importance of a broader assessment for patients with a geriatric perspective and involvement of multi-disciplinary team.

Rapid Growth between 0 and 2 Years Old in Healthy Infants Born at Term and Its Relationship with Later Obesity: A Systematic Review and Meta-Analysis of Evidence.

INTRODUCTION: Rapid growth in early childhood has been identified as a possible risk factor for long-term adiposity. However, there is a lack of studies quantifying this phenomenon only in healthy, full-term infants with appropriate birth weight for gestational age. This systematic review and meta-analysis aimed to investigate the association of rapid growth in full-term children up to 2 years of age with adiposity up to 18 years of age. METHODOLOGY: A systematic review of the literature was conducted in PubMed, EMBASE, and Web of Science. RESULTS: 14 studies were included. We were unable to find strong evidence that rapid growth in early childhood is a risk factor for long-term adiposity. Rapid growth in early childhood was associated with taller heights (standardized mean difference: 0.51 (CI: 0.25-0.77)) and higher body mass index (standardized mean difference: 0.50 (CI: 0.25-0.76)) and a higher risk of overweight under 18 years. CONCLUSION: Rapid growth in early childhood in term infants with appropriate birth weight is associated with higher growth, body mass index, and risk of being overweight up to age 18, but further work is needed to identify the associations between early rapid growth and obesity later in adulthood.

Ibrutinib-Related Uveitis in Non-Hodgkin Lymphoma Patients: A Case Report and Literature Review.

PURPOSE: To report two cases of ibrutinib-related uveitis and review the literature to date. METHODS: We report two cases of ibrutinib-related uveitis using CARE guidelines and review the cases reported in the literature. RESULTS: Case 1) A 55-year-old female with recurrent primary central nervous system lymphoma presented with bilateral decreased visual acuity, photophobia, and floaters that started one month after initiating oral treatment with ibrutinib. Chronic non-granulomatous bilateral anterior-intermediate uveitis with macular edema was identified. Secondary causes were ruled out, and a presumptive diagnosis of ibrutinib-related uveitis was made. Case 2) A 57-year-old female with Waldenström macroglobulinemia who was treated with ibrutinib for two years presented with bilateral blurred vision, photophobia, red eyes, and floaters. A diagnosis of non-granulomatous, noninfectious panuveitis with bilateral cystoid macular edema was made. Secondary causes were ruled out, and ibrutinib toxicity was the most likely cause. CONCLUSION: Ibrutinib-related uveitis is a novel and under-diagnosed clinical entity. The most frequent clinical presentation in the literature is bilateral, non-granulomatous, anterior, and intermediate uveitis. Macular edema is a frequent complication. Uveitis usually requires topical treatment and the suspension of ibrutinib. Switching to second-generation Bruton tyrosine kinase inhibitors is proposed as a potential therapeutic alternative.

The Indigenous Probiotic Lactococcus lactis PH3-05 Enhances the Growth, Digestive Physiology, and Gut Microbiota of the Tropical Gar (Atractosteus tropicus) Larvae.

Probiotics in aquaculture hold promise for enhancing fish health and growth. Due to their increased specificity and affinity for their host, indigenous probiotics may offer isolated and potentially amplified benefits. This study investigated the effects of Lactococcus lactis PH3-05, previously isolated from adults of tropical gar (Atractosteus tropicus), on the growth, survival, digestive enzyme activity, intestinal morphology, expression of barrier and immune genes, and intestinal microbiota composition in the larvae of tropical gar. Larvae were fed with live L. lactis PH3-05 concentrations of 104, 106, and 108 CFU/g for 15 days alongside a control diet without probiotics. Higher concentrations of L. lactis PH3-05 (106 and 108 CFU/g) positively influenced larval growth, increasing hepatocyte area and enterocyte height. The 106 CFU/g dose significantly enhanced survival (46%) and digestive enzyme activity. Notably, the 108 CFU/g dose stimulated increased expression of muc-2 and il-10 genes, suggesting enhanced mucosal barrier function and anti-inflammatory response. Although L. lactis PH3-05 did not significantly change the diversity, structure, or Phylum level composition of intestinal microbiota, which was constituted by Proteobacteria, Bacteroidota, Chloroflexi, and Firmicutes, an increase in Lactobacillus abundance was observed in fish fed with 106 CFU/g, suggesting enhanced probiotic colonization. These results demonstrate that administering L. lactis PH3-05 at 106 CFU/g promotes growth, survival, and digestive health in A. tropicus larvae, establishing it as a promising indigenous probiotic candidate for aquaculture applications.

A Case Report and Literature Review of a Giant Bladder Stone in a 43-year-old Female (9 x 8 x 4 cm, 250g).

Cystoliths are an uncommon manifestation of urolithiasis. They are typically observed in male patients who are over the age of 45. A giant bladder calculus is a stone that is greater than 4 cm in diameter and weighs more than 100 g. We report the case of a 43- year-old female who was admitted to the urology department with dysuria, lower abdominal pain, fever, nausea, and microscopic hematuria. Mild tenderness in the suprapubic region was noted during the patient's physical examination. A hyperdense image measuring 7.2 x 6.4 cm was revealed during an abdominal CT scan, which confirmed the diagnosis. A 280 g stone, measuring 9 x 8 x 4 cm, was extracted through open cystolithotomy. In the female population, bladder calculus formation is uncommon. The standard treatment is open cystolithotomy, and computed tomography is a valuable tool for confirming the diagnosis.

Impact of KDM6B mosaic brain knockout on synaptic function and behavior.

Autism spectrum disorders (ASD) are complex neurodevelopmental conditions characterized by impairments in social communication, repetitive behaviors, and restricted interests. Epigenetic modifications serve as critical regulators of gene expression playing a crucial role in controlling brain function and behavior. Lysine (K)-specific demethylase 6B (KDM6B), a stress-inducible H3K27me3 demethylase, has emerged as one of the highest ASD risk genes, but the precise effects of KDM6B mutations on neuronal activity and behavioral function remain elusive. Here we show the impact of KDM6B mosaic brain knockout on the manifestation of different autistic-like phenotypes including repetitive behaviors, social interaction, and significant cognitive deficits. Moreover, KDM6B mosaic knockout display abnormalities in hippocampal excitatory synaptic transmission decreasing NMDA receptor mediated synaptic transmission and plasticity. Understanding the intricate interplay between epigenetic modifications and neuronal function may provide novel insights into the pathophysiology of ASD and potentially inform the development of targeted therapeutic interventions.

Impact of a social media-delivered distance learning program on mhGAP training among primary care providers in Jalisco, Mexico.

BACKGROUND: The World Health Organization's (WHO) Mental Health Gap Action Programme (mhGAP) aims to provide evidence-based guidelines for the management of mental, neurological, and substance use disorders in non-specialized healthcare settings. However, implementing these guidelines remains a challenge due to various factors, including limited training opportunities for primary care providers. This study con the effectiveness of a social media-delivered distance education program on the mhGAP intervention guide, to overcome barriers of technology access and digital literacy, providing a familiar and accessible platform for primary care providers in Jalisco. METHODS: A quasi-experimental study with a pre-test/post-test design was conducted. Primary care providers from Jalisco were invited to participate in a distance education program on the mhGAP intervention guide. The program consisted of online modules, webinars, and discussion forums facilitated by mental health experts. Knowledge assessments were conducted before and after the intervention using a standardized questionnaire. Participant satisfaction and perceived utility were also evaluated through surveys and focus group discussions. RESULTS: A total of 1,096 primary care providers completed the program. The mean knowledge score significantly improved from 58.2% (SD = 12.8%) in the pre-test to 81.4% (SD = 9.6%) in the post-test (p < 0.001), with a large effect size (Cohen's d = 2.04). Subgroup analyses revealed consistent knowledge gains across different demographic and professional characteristics. Participant satisfaction was high, with 92% rating the program's overall quality as "good" or "excellent." Qualitative findings highlighted the benefits of accessibility, flexibility, interactivity, and practical applicability of the distance education approach. CONCLUSIONS: The social media-delivered distance education program on the mhGAP intervention guide effectively improved the knowledge of primary care providers in Jalisco, Mexico. Participants reported high levels of satisfaction and perceived utility. This study demonstrates the potential of distance education strategies to disseminate evidence-based guidelines and enhance mental health service delivery in primary care settings, particularly in resource-limited areas.

3D-printed aerogels as theranostic implants monitored by fluorescence bioimaging.

Aerogel scaffolds are nanostructured materials with beneficial properties for tissue engineering applications. The tracing of the state of the aerogels after their implantation is challenging due to their variable biodegradation rate and the lack of suitable strategies capable of in vivo monitoring the scaffolds. Upconversion nanoparticles (UCNPs) have emerged as advanced tools for in vitro bioimaging because of their fluorescence properties. In this work, highly fluorescent UCNPs were loaded into aerogels to obtain theranostic implants for tissue engineering and bioimaging applications. 3D-printed alginate-hydroxyapatite aerogels labeled with UCNPs were manufactured by 3D-printing and supercritical CO2 drying to generate personalize-to-patient aerogels. The physicochemical performance of the resulting structures was evaluated by printing fidelity measurements, nitrogen adsorption-desorption analysis, and different microscopies (confocal, transmission and scanning electron microscopies). Stability of the aerogels in terms of physicochemical properties was also tested after 3 years of storage. Biocompatibility was evaluated in vitro by different cell and hemocompatibility assays, in ovo and in vivo by safety and bioimaging studies using different murine models. Cytokines profile, tissue index and histological evaluations of the main organs unveiled an in vivo downregulation of the inflammation after implantation of the scaffolds. UCNPs-decorated aerogels were first-time manufactured and long-term traceable by fluorescence-based bioimaging until 3 weeks post-implantation, thereby endorsing their suitability as tissue engineering and theranostic nanodevices (i.e. bifunctional implants).

Intersecting Pathologies: A Case Report on the Co-presentation of Quasi-Moyamoya Disease and Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal Plasma Cell Disorder, and Skin Changes (POEMS) Syndrome.

Moyamoya disease (MMD) is a rare chronic vasculopathy characterized by progressive stenosis of the internal carotid arteries and the formation of fragile collateral vessels in the brain. Polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, and skin changes (POEMS) syndrome is a rare paraneoplastic syndrome with a complex presentation that includes polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes. Here, we report a unique case of a 54-year-old male with MMD presenting with recurrent speech loss and mumbling, later diagnosed with POEMS syndrome. Initial imaging revealed Moyamoya vasculopathy, confirmed by computed tomographic angiography (CTA) and magnetic resonance imaging (MRI). Further examination revealed polyneuropathy, organomegaly, and elevated vascular endothelial growth factor (VEGF), meeting the diagnostic criteria for POEMS syndrome. The patient was treated with a cyclophosphamide-bortezomib-dexamethasone regimen, followed by the addition of daratumumab, resulting in clinical improvement. This case highlights the importance of thorough diagnostics and a multidisciplinary treatment approach for patients with complex comorbidities, emphasizing the need for early detection and targeted therapy in managing dual pathologies of MMD and POEMS syndrome.

Negative association of steroids with immunotherapy efficacy in a multi-tumor cohort: time and dose-dependent.

Previous studies have suggested a negative impact of steroids on the efficacy of immune checkpoint inhibitors (ICI), but how this effect is modulated by the dosage and time of administration is yet to be clarified. We have performed a retrospective analysis of 475 patients with advanced solid tumors treated with ICI as monotherapy from 2015 to 2022. Data regarding immune-related adverse events (irAEs) and clinical outcomes were collected. For each patient, the daily steroid dose (in mg/kg of prednisone) was registered until disease progression or death. The impact of cumulative doses on response rates and survival outcomes was analyzed within different periods. The objective response rate (ORR) was significantly lower among patients exposed to steroids within 30 days before the first cycle of ICI (C1) (20.3% vs. 36.7%, p < 0.01) and within the first 90 days of treatment (25.7% vs. 37.7%, p = 0.01). This negative association was confirmed by multivariable analysis. Higher mean steroid doses were observed among non-responders, and cumulative doses were inversely correlated with the disease control rate (DCR) around ICI initiation. Remarkably, poorer outcomes were observed even in patients belonging to the lowest dose quartile compared to the steroid-naïve population. The exposure to steroids after 6 months of ICI was not associated with worse survival outcomes. Our results suggest that the potential impact of steroids on ICI efficacy may be time-dependent, prevailing around ICI initiation, and dose-dependent, with modulation of neutrophil-to-lymphocyte ratio as a possible underlying mechanism.

Dysregulated zinc homeostasis and microadenomas in the anterior pituitary: pathological insights into suicide risk.

Background: Suicide is a significant public health problem influenced by various risk factors, including dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis. Zinc (Zn), essential for pituitary function in hormone synthesis and release, has been linked to suicide, with studies noting reduced serum levels and altered brain transport mechanisms. Despite Zn's crucial role in pituitary function and its involvement in suicidal behavior, information on pituitary Zn in suicide is scarce. Tumor cells modify Zn dynamics in tissues, and a previous report suggests microadenomas in the anterior pituitary as a risk factor for suicide. Methods: Histopathological analysis with hematoxylin-eosin stain and histochemical techniques to assess Zn homeostasis were carried out on anterior pituitary postmortem samples from 14 suicide completers and 9 non-suicidal cases. Results: Pituitary microadenomas were identified in 35% of suicide cases and none in the non-suicidal cases. Furthermore, compartmentalized Zn (detected via dithizone reactivity), but not free Zn levels (detected via zinquin reactivity), was lower in the suicide cases compared to the non-suicidal group. Conclusion: This is the first report of a potential association between disrupted Zn homeostasis and microadenomas in the anterior pituitary as a feature in suicide and provides critical insights for future neuroendocrine Zn-related research.

Microbiome and Metabolome Restoration After Administration of Fecal Microbiota, Live-jslm (REBYOTA®) for Preventing Recurrent Clostridioides difficile Infection.

BACKGROUND: Microbiota-based treatments are effective in preventing recurrent Clostridioides difficile infection (rCDI). Fecal microbiota, live-jslm (REBYOTA®; RBL, previously RBX2660) was shown to prevent rCDI in a phase 3, randomized, double-blinded placebo controlled clinical trial (PUNCH™ CD3). METHODS: Stool samples from participants in PUNCH™ CD3 who received a single blinded dose of rectally administered RBL or placebo were sequenced to determine microbial community composition and calculate the Microbiome Health Index for post-antibiotic dysbiosis (MHI-A). The composition of bile acids (BAs) in the same samples was quantified by liquid chromatography mass spectrometry. Relationships between BA composition and microbiota community structure and correlations with treatment outcomes were assessed. RESULTS: Before administration, Gammaproteobacteria and Bacilli dominated the microbiota community and primary BAs were more prevalent than secondary BAs. Clinical success after administration correlated with shifts to predominantly Bacteroidia and Clostridia, a significant increase in MHI-A, and a shift from primary to secondary BAs. Several microbiota and BA changes were more extensive in RBL-treated responders compared to placebo-treated responders, and microbiota changes correlated with BA changes. CONCLUSIONS: Clinical response and RBL administration were associated with significant restoration of microbiota and BA composition. CLINICAL TRIALS REGISTRATION: NCT03244644.

Estigma de identidad sexual y apoyo social entre los hombres que tienen sexo con otros hombres en Central y Asunción, Paraguay: un análisis cualitativo

Introducción: El estigma relacionado con la identidad sexual, especialmente entre HSH, sigue siendo un desafío importante en muchas culturas, este estigma puede aparecer de varias maneras, desde una discriminación explícita hasta estereotipos más discretos, y puede afectar negativamente la salud mental y emocional de quienes lo sufren. Objetivo: Analizar el estigma de identidad sexual y apoyo social entre los hombres que tienen sexo con otros hombres en Central y Asunción, Paraguay durante el 2024. Metodología: Estudio cualitativo, fenomenológico de tipo descriptivo y explicativo. Las categorías de análisis consideradas en este estudio fueron: a) Estigma y apoyo social en la comunidad en general, b) Divulgación de identidad sexual a la comunidad en general, c) Divulgación de identidad sexual a familiares y amigos y d) Estigma y apoyo social en la comunidad de LGBT. Resultados: Participaron del estudio, nueve HSH, donde los testimonios revelan el profundo anhelo de vivir con autenticidad y libertad. Los HSH en Paraguay desean poder ser ellos mismos sin temor a ser juzgados o rechazados, anhelan relaciones abiertas y honestas, y aspiran a una comunidad donde puedan compartir experiencias y apoyarse mutuamente Conclusión: Los HSH enfrentan obstáculos en su crecimiento y unión como comunidad. La ausencia de una comunidad fuerte y unida dificulta el apoyo mutuo y el desarrollo personal, además de la competencia y la falta de colaboración entre organizaciones e individuos crean un ambiente dividido, donde cada uno busca sus propios beneficios en lugar de trabajar juntos por el bien de todos.

Introduction: Stigma related to sexual identity, especially among MSM, remains a major challenge in many cultures, this stigma can appear in various ways, from explicit discrimination to more discreet stereotypes, and can negatively affect the mental and emotional health of those who suffer from it. Objective: Analyze the stigma of sexual identity and social support among men who have sex with other men in Central and Asunción, Paraguay during 2024. Methodology: Qualitative, Phenomenological Study of a descriptive and explanatory type. The analysis categories considered in this study were: a) Stigma and social support in the community in general, b) Disclosure of sexual identity to the community in general, c) Disclosure of sexual identity to family and friends and d) Stigma and social support in the LGBT community. Results: Nine MSM participated in the study, where the testimonies reveal the deep desire to live with authenticity and freedom. MSM in Paraguay want to be able to be themselves without fear of being judged or rejected, they long for open and honest relationships, and they aspire to a community where they can share experiences and support each other. Conclusion: MSM face obstacles in their growth and unity as a community. The absence of a strong and united community makes mutual support and personal development difficult, in addition to competition and lack of collaboration between organizations and individuals creating a divided environment, where everyone seeks their own benefits instead of working together for the good. of everyone.

Plasma Antioxidant Capacity Is Related to Dietary Intake, Body Composition, and Stage of Reproductive Aging in Women.

BACKGROUND: women aging is a normal process of life; however, hormonal changes create an imbalance between prooxidants and antioxidants and could be measured as the antioxidant capability (AC) of an organism. OBJECTIVE: to find the association between plasma AC levels, dietary intakes, and body composition in 18-64-year-old women living in the northeast of Mexico. METHODS: A total of n = 514 women (18-64 years old) were grouped according to STRAW criteria as reproductive, menopausal transition, and postmenopausal. Anthropometrics, body mass index (BMI), weight-hip ratio (WHR), and weight-height ratio WHtR were determined, and percentage of body fat was analyzed by bioelectrical impedance. Dietary intake of macronutrients and vitamins A, E, and C were analyzed by a 3-day food recall. The AC status in plasma was analyzed by the ORACFL assay. RESULTS: Plasma AC levels were higher in postmenopausal women (815 µmol TE/L), and menopausal transition women (806 µmol TE/L) than in reproductive women (633 µmol TE/L). BMI was overweight (>25 kg/m2) in all three groups. WHtR and WHR are above the healthy limit of 0.5 and 0.8, respectively for both menopausal transition and postmenopausal women. In reproductive women, negative relationships were calculated between plasma AC and age (Rho = -0.250, p = 0.007), BMI (Rho = -0.473, p < 0.001), WHtR (Rho = -0.563, p < 0.001), WHR (Rho = -0.499, p < 0.001), and % body fat (Rho = -0.396, p < 0.001). A negative association was determined between plasma AC and WHtR in reproductive women (B = -2.718, p = 0.026). No association resulted for those in menopausal transition, and a positive association was obtained between plasma AC and protein (B = 0.001, p = 0.024) and vitamin E (B = 0.003, p = 0.013) intakes in postmenopausal women. CONCLUSIONS: the antioxidant capability (AC) in plasma was lower in reproductive women, and anthropometric parameters marking decreased physical fitness were associated with decreased AC.

Blood donor questionnaires and infectious disease screening in Latin American countries.

BACKGROUND AND OBJECTIVES: Blood donor questionnaires are tools used to screen prospective blood donors to determine their eligibility. There are limited data regarding blood donor questionnaires and infectious disease screening of the blood supply in Latin American countries. This study aimed to survey donor centres in Latin American countries to learn more about blood donor screening and infection assessment. MATERIALS AND METHODS: An international team of transfusion medicine professionals including medical directors and supervisors who work or collaborate with Latin American donor centres, called 'Comité de Investigación en Medicina Transfusional', designed a survey (16 questions) to characterize blood donor eligibility in Latin America. RESULTS: Eighty-two institutions from 14 Latin American countries responded to the survey. Most donor centres (66%; 54 of 82) had a donor deferral percentage between 5% and 25%, and the most common causes of deferrals were low haemoglobin and high-risk behaviour. Most donors in blood centres were directed family donors compared with voluntary donors. Infection evaluation included mostly serologic assessment (81%; 30 of 37) for human immunodeficiency virus (HIV), Hepatitis B, Hepatitis C, Treponema pallidum and Trypanosoma cruzi rather than nucleic acid tests (5%; 2 of 37). CONCLUSION: Heterogeneity exists in donor selection and infectious disease screening in Latin American countries. This survey provides valuable information to understand Latin American blood centre practices.

Histological study of the development of the digestive system during larval feeding in the pike silverside Chirostoma estor.

Chirostoma estor (Jordan, 1879) is an endemic freshwater species with a high potential for aquaculture; however, as in many other fish, larviculture of this species is the most critical stage, in which the higher mortality rates. Therefore, it is necessary to fully describe the development of the digestive system to establish better feeding protocols in the larval culture of C. estor, both for aquaculture and restoration purposes. In the present study, larviculture was carried out from hatching to 20 days after hatching (DAH). The organisms were fed with the rotifer Brachionus plicatilis from 2 to 14 DAH, and nauplii of Artemia sp. from 15 to 20 DAH. A total of 12 organisms (0, 3, 5, 10, 15, and 20 DAH) were taken for size and weight growth and histological and histochemical analysis. The histological analysis indicated that after 3 DAH, the opening of the mouth and anus was observed, coinciding with the beginning of exogenous feeding. In addition, the digestive system developed, with differentiation of the oropharyngeal sections, esophagus, and intestine, folding of the intestinal mucosa, as well as associated organs (liver and pancreas) that reach their maximum development at 20 DAH. Thus, C. estor at this stage of development can digest and absorb nutrients despite being an agastric fish. The results obtained in this study will facilitate a better understanding of the ontogenetic morphophysiological development processes, associated with the transition of larvae to exogenous feeding, which ensures a higher percentage of survival during larval development and of course, adds to the diversity ontogenetics of teleostean.

Seasonal Stability of the Circadian Rhythm in Patients with Type I Myocardial Infarction.

Background: A circadian rhythm of myocardial infarction has been described but there is little data on its relation with seasons and months. Methods: From June 2013 to June 2018, we analyzed the alerts for acute ST-segment elevation myocardial infarction (STEMI) in a Spanish region with 6.64 million inhabitants, universal health coverage, and an organized STEMI reperfusion network. We selected those patients which an identifiable culprit plaque. Results: We recruited 6765 cases of STEMI due to type I acute myocardial infarction (type-I AMI), with mean age of 63.2 years (range 17-101, standard deviation [SD] 13.7), 5238 were males (77.4%) and 2801 (41.9%) were 65 years or older. The hourly distribution followed a fixed pattern in all months, with most of the events occurring between 6:00 AM and 4:00 PM, a peak at approximately 01:00 PM and a valley between 10:00 PM and 06:00 AM. No significant difference was found when comparing the mean time to first medical contact between July (the month with more daylight hours) and December (the month with shortest days). No significant differences were found between male and female patients, or between patients aged 65 years or older and younger patients. There was a close correlation between the number of events per month and the number of events occurring during the day (6 AM to 6 PM, r = 0.988, p = 0.001) and during the night (6 PM to 6 AM, r = 0.944, p < 0.001), with different slopes of the regression lines (t-test, p < 0.001), so that the difference between day-night occurrences increased with the total incidence. Conclusions: There is a circadian pattern in the presentation of STEMI that is not influenced by sex and age. The different incidence of STEMI at different times of the year does not affect the circadian pattern in terms of the shape of the curve or the mean time of presentation, although diurnal events increase more than nocturnal events, suggesting that triggers are most likely to act during vulnerable periods as determined by a circadian-based rhythm.