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Identify risk factors that could increase progression to severe disease and mortality in hospitalized SARS-CoV-2 patients in the Southeast US.
Design, Setting, and Participants
Multicenter, retrospective cohort including 502 adults hospitalized with laboratory-confirmed COVID-19 between March 1, 2020 and May 8, 2020 within one of 15 participating hospitals in 5 health systems across 5 states in the Southeast US.
The study objectives were to identify risk factors that could increase progression to hospital mortality and severe disease (defined as a composite of intensive care unit admission or requirement of mechanical ventilation) in hospitalized SARS-CoV-2 patients in the Southeast US.
A total of 502 patients were included, and the majority (476/502, 95%) had clinically evaluable outcomes. Hospital mortality was 16% (76/476), while 35% (177/502) required ICU admission, and 18% (91/502) required mechanical ventilation. By both univariate and adjusted multivariate analysis, hospital mortality was independently associated with age (adjusted odds ratio [aOR] 2.03 for each decade increase, 95% CI 1.56-2.69), male sex (aOR 2.44, 95% CI: 1.34-4.59), and cardiovascular disease (aOR 2.16, 95% CI: 1.15-4.09). As with mortality, risk of severe disease was independently associated with age (aOR 1.17 for each decade increase, 95% CI: 1.00-1.37), male sex (aOR 2.34, 95% CI 1.54-3.60), and cardiovascular disease (aOR 1.77, 95% CI 1.09-2.85).
In an adjusted multivariate analysis, advanced age, male sex, and cardiovascular disease increased risk of severe disease and mortality in patients with COVID-19 in the Southeast US. In-hospital mortality risk doubled with each subsequent decade of life.
Inflammation may contribute to the high prevalence of depressive symptoms seen in lung cancer. “Sickness behavior” is a cluster of symptoms induced by inflammation that are similar but distinct from depressive symptoms. The Sickness Behavior Inventory-Revised (SBI-R) was developed to measure sickness behavior. We hypothesized that the SBI-R would demonstrate adequate psychometric properties in association with inflammation.
Participants with stage IV lung cancer (n = 92) were evaluated for sickness behavior using the SBI-R. Concomitant assessments were made of depression (Patient Hospital Questionniare-9, Hospital Anxiety and Depression Scale) and inflammation [C-reactive protein (CRP)]. Classical test theory (CTT) was applied and multivariate models were created to explain SBI-R associations with depression and inflammation. Factor Analysis was also used to identify the underlying factor structure of the hypothesized construct of sickness behavior. A longitudinal analysis was conducted for a subset of participants.
The sample mean for the 12-item SBI-R was 8.3 (6.7) with a range from 0 to 33. The SBI-R demonstrated adequate internal consistency with a Cronbach's coefficient of 0.85, which did not increase by more than 0.01 with any single-item removal. This analysis examined factor loadings onto a single factor extracted using the principle components method. Eleven items had factor loadings that exceeded 0.40. SBI-R total scores were significantly correlated with depressive symptoms (r = 0.78, p < 0.001) and CRP (r = 0.47, p < 0.001). Multivariate analyses revealed that inflammation and depressive symptoms explained 67% of SBI-R variance.
Significance of results
The SBI-R demonstrated adequate reliability and construct validity in this patient population with metastatic lung cancer. The observed findings suggest that the SBI-R can meaningfully capture the presence of sickness behavior and may facilitate a greater understanding of inflammatory depression.
Evaluate changes in antimicrobial use during COVID-19 and after implementation of a multispecialty COVID-19 clinical guidance team compared to pre–COVID-19 antimicrobial use.
Retrospective observational study.
Tertiary-care academic medical center.
Internal medicine and medical intensive care unit (MICU) provider teams and hospitalized COVID-19 patients.
Difference-in-differences analyses of antibiotic days of therapy per 1,000 patient days present (DOT) for internal medicine and MICU teams treating COVID-19 patients versus teams that did not were performed for 3 periods: before COVID-19, initial COVID-19 period, and after implementation of a multispecialty COVID-19 clinical guidance team which included daily, patient-specific antimicrobial stewardship recommendations. Patient characteristics associated with antibiotic DOT were evaluated using multivariable Poisson regression.
In the initial COVID-19 period, compared to the pre–COVID-19 period, internal medicine and MICU teams increased weekly antimicrobial use by 145.3 DOT (95% CI, 35.1–255.5) and 204.0 DOT (95% CI, −16.9 to 424.8), respectively, compared to non–COVID-19 teams. In the intervention period, internal medicine and MICU COVID-19 teams both had significant weekly decreases of 362.3 DOT (95% CI, −443.3 to −281.2) and 226.3 DOT (95% CI, −381.2 to –71.3). Of 131 patients hospitalized with COVID-19, 86 (65.6%) received antibiotics; no specific patient factors were significantly associated with an expected change in antibiotic days.
Antimicrobial use initially increased for COVID-19 patient care teams compared to pre–COVID-19 levels but significantly decreased after implementation of a multispecialty clinical guidance team, which may be an effective strategy to reduce unnecessary antimicrobial use.
The unique gold pendant found at Chrysolakkos, Malia, Crete, in 1930 has been variously interpreted, and usually is said to represent a pair of bees. This vague interpretation is discussed, and it is pointed out that the three discs that are suspended from the pendant closely resemble the fruits of a native Cretan herb, Tordylium apulum. Megascolia maculata, a member of the order Hymenoptera, is proposed as the model for the insects. Like a gold toggle pin, also from Chrysolakkos, the pendant demonstrates that Cretan goldsmiths were capable of creating aesthetically pleasing work by paying close attention to the local flora and fauna and used examples as the models for their unique jewellery
Advanced cancer patients who are parents of minor children experience heightened psychosocial distress. Oncology social workers (OSWs) are essential providers of psychosocial support to parents with advanced cancer. Yet, little is known about the experiences and approaches of OSWs in addressing these patients’ unique needs. The purpose of this study was to characterize the attitudes, practice behaviors, and training experiences of OSWs who provide psychosocial care for advanced cancer patients with minor children.
Forty-one OSWs participated in a cross-sectional survey addressing multiple facets of their psychosocial care for parents with advanced cancer. The five assessed domains of psychosocial support were communication support, emotional support, household support, illness and treatment decision-making support, and end-of-life planning.
Participants reported greatest confidence in counseling patients on communication with children about illness and providing support to co-parents about parenting concerns. OSWs reported less confidence in counseling parents on end-of-life issues and assisting families with non-traditional household structures. The majority of participants reported needing more time in their clinical practice to sufficiently address parents’ psychosocial needs. Nearly 90% of participants were interested in receiving further training on the care of parents with advanced cancer.
Significance of results
To improve the care of parents with advanced cancer, it is critical to understand how the psychosocial oncology workforce perceives its clinical practice needs. Study findings suggest an opportunity for enhanced training, particularly with respect to end-of-life needs and in response to the changing household structure of American families.
In animal models, exposure to excess testosterone during gestation induces polycystic ovary syndrome (PCOS)-like reproductive and metabolic traits in female offspring, suggesting that the hyperandrogenemic intrauterine environment may have a role in the etiology of PCOS. Additionally, few studies have also addressed metabolic and reproductive outcomes in male offspring. In the present study, the intravenous glucose tolerance test (IGTT) was used to assess the insulin–glucose homeostasis at various ages during sexual development in male sheep born to testosterone-treated ewes. To further analyze the programming effect of testosterone on insulin–glucose homeostasis, indexes of insulin sensitivity were assessed in orchidectomized post-pubertal males born to testosterone-treated ewes (Torq-males) and orchidectomized post-puberal controls (Corq-males) before and 48 h after a testosterone injection. There was no difference in insulin sensitivity indexes between males born to testosterone-treated ewes (T-males) and control males born to control ewes (C-males) at 5, 10, 20 and 30 weeks of age, representing the infantile, early and late pre-pubertal, and early post-pubertal stage of sexual development, respectively. In orchidectomized males, basal levels of insulin and glucose were not different between both groups before and after the testosterone injection; however, Torq-males released more insulin before and after T challenge during the first 20 min of the test. Despite this, plasma glucose concentrations were not different in both groups during IVGTT, resulting in an insulin sensitivity index composite similar between groups. We concluded that the effect of prenatal exposure to excess testosterone may reprogram the pancreatic β-cells insulin release in ovine males, with effects more evident in castrated males versus intact males.
Women are still underrepresented as public-sector organizational leaders, despite comprising half of the United States public-sector workforce. To explore the factors driving gender imbalance, this Element employs a problem-driven approach to examine gender imbalance in local government management. We use multiple methods, inductive and deductive research, and different theoretical frames for exploring why so few women are city or county managers. Our interviews, resume analysis and secondary data analysis suggesting that women in local government management face a complex puzzle of gendered experiences, career paths and appointment circumstances that lend insights into gender imbalanced leadership in this domain.
To evaluate the impact of a pharmacist-driven Staphylococcus aureus bacteremia (SAB) safety bundle supported by leadership and to compare compliance before and after implementation.
Retrospective cohort study with descriptive and before-and-after analyses.
Tertiary-care academic medical center.
All patients with documented SAB, regardless of the source of infection, were included. Patients transitioned to palliative care were excluded from before-and-after analysis.
A pharmacist-driven safety bundle including documented clearance of bacteremia, echocardiography, removal of central venous catheters, and targeted intravenous therapy of at least 2 weeks duration was implemented in November 2015 and was supported by leadership with stepwise escalation for nonresponse. A descriptive analysis of all patients with SAB during the study period included pharmacy interventions, acceptance rates, and escalation rates. A pre–post implementation analysis of 100 sequential patients compared bundle compliance and descriptive parameters.
Overall, 391 interventions were made in the 20-month period following implementation, including 20 “good saves” avoiding potentially major adverse events. No statistically significant differences in complete bundle compliance were detected between the periods (74% vs 84%; P = .08). However, we detected a significant increase in echocardiography after the bundle was implemented (83% vs 94%; P = .02) and fewer patients received suboptimal definitive therapy after the bundle was implemented (10% vs 3%; P = .045).
This pharmacist-driven SAB safety bundle with leadership support showed improvement in process measures, which may have prevented major adverse events, even with available infectious diseases (ID) consultation. It provides a critical safety net for institutions without mandatory ID consultation or with limited antimicrobial stewardship resources.
Cryoplanation terraces are prominent but enigmatic landforms found in present and past periglacial environments. Geomorphologists have debated for more than a century over processes involved in the formation of these elevated, step-like, bedrock features. Presented here are the first numerical surface exposure ages and scarp retreat rates from cryoplanation terraces in the Yukon-Tanana Upland (YTU) in Alaska, part of unglaciated eastern Beringia, obtained from terrestrial cosmogenic nuclides (TCN) in surface boulders. Ages comprise six 10Be TCN ages from two terrace treads near Eagle Summit and six 36 Cl ages from two treads on Mt. Fairplay. Based on these exposure ages, scarps at both locations were last actively eroding from 49 to 22.4 ka. Both locations exhibit time-transgressive development, particularly near scarp-tread junctions. Boulder exposure ages and distances between sampled boulder locations were used to estimate scarp retreat rates of 0.11 to 0.56 cm/yr. These numerical exposure ages presented here demonstrate that the cryoplanation terraces in the YTU are diachronous surfaces actively eroding during multiple cold intervals. With these results, hypotheses for cryoplanation terrace formation are discussed and evaluated for the YTU, including those based on geologic structure, nivation, and the influence of permafrost.
To identify predictors of remission with placebo treatment in double-blind randomized controlled trials (RCTs) in major depressive disorder (MDD) based on baseline characteristics.
989 placebo-treated MDD subjects with baseline Hamilton Depression Rating Scale total score (HAMDT17) ≥15 who completed 7-8 weeks of treatment from 8 duloxetine RCTs with placebo lead-in were included. Remission was defined as HAMDT17 endpoint score ≤7. Stepwise logistic regression and classification and regression tree (CART) methods were used to identify predictors of remission. Data were randomly split into training data (N=791, 80%) for model selection and test data (N=198, 20%) for validation. Predictive quality of models was assessed by ROC curves.
In the logistic regression analysis, out of >50 potential pre-treatment predictors, the HAMDT17 score, age, Hamilton Anxiety Scale item 14 (HAMA14: behavior at interview) and length of current MDD episode (length) were found to be most predictive for remission on placebo. These variables were also identified as top predictors by the CART method that identified 2 subgroups: “HAMA14=0 OR (HAMDT17< 22 AND length< 18 weeks)” (45% remitted), “HAMA14>0 AND (HAMDT17≥22 OR length≥18 weeks)” (21% remitted). However, the predictive power was weak for both methods with areas under the ROC curve (test data) of 67% and 56%, respectively.
Baseline risk factors for non-remission after 7-8 weeks of placebo treatment were older age, more severe depressive symptoms, apparent anxiety, and a longer duration of current MDD episode. These results are consistent with previous findings and may aid in the design of RCTs.
Two randomized, controlled trials of L-methylfolate augmentation of SSRIs for major depressive disorder (MDD) were conducted using a novel study design (sequential parallel comparison design- SPCD).
To evaluate the efficacy of L-methylfolate augmentation using the Hamilton Depression Rating Scale.
In study one (TRD-1), 148 outpatients with SSRI-resistant MDD were enrolled in a 60-day, SPCD study, divided into two 30-day periods (phases 1 and 2). Patients were randomized 2:3:3 to receive L-methylfolate (7.5mg/d in phase 1, 15mg/d in phase 2), placebo in phase 1 followed by L-methylfolate 7.5mg/d in phase 2, or placebo for both phases. Study two (TRD-2) involved 75 patients and was identical in design to TRD-1 except for the dose of L-methylfolate (15mg only).
In the TRD-1 Study, L-methylfolate 7.5 mg/d was not found to be more effective than placebo. In phase 1 of the TRD-2 Study, 37% of patients on L-methylfolate 15mg/d responded and 18% of placebo patients responded, while in phase 2 among placebo non-responders, the response rates were 28% on L-methylfolate 15mg/d and 9.5% on placebo. When phases 1 and 2 were pooled according to the SPCD model, the difference in response rates was statistically significant in favor of L-methylfolate (p = 0.0399). The rates of spontaneously reported AEs and rates of study discontinuation appear r comparable between L-methylfolate and placebo in both studies. Rates of study discontinuation were also comparable
These studies suggest that L-methylfolate 15 mg/d may be a safe and effective augmentation strategy for inadequate response to SSRIs.
Many institutions are attempting to implement patient-reported outcome (PRO) measures. Because PROs often change clinical workflows significantly for patients and providers, implementation choices can have major impact. While various implementation guides exist, a stepwise list of decision points covering the full implementation process and drawing explicitly on a sociotechnical conceptual framework does not exist.
To facilitate real-world implementation of PROs in electronic health records (EHRs) for use in clinical practice, members of the EHR Access to Seamless Integration of Patient-Reported Outcomes Measurement Information System (PROMIS) Consortium developed structured PRO implementation planning tools. Each institution pilot tested the tools. Joint meetings led to the identification of critical sociotechnical success factors.
Three tools were developed and tested: (1) a PRO Planning Guide summarizes the empirical knowledge and guidance about PRO implementation in routine clinical care; (2) a Decision Log allows decision tracking; and (3) an Implementation Plan Template simplifies creation of a sharable implementation plan. Seven lessons learned during implementation underscore the iterative nature of planning and the importance of the clinician champion, as well as the need to understand aims, manage implementation barriers, minimize disruption, provide ample discussion time, and continuously engage key stakeholders.
Highly structured planning tools, informed by a sociotechnical perspective, enabled the construction of clear, clinic-specific plans. By developing and testing three reusable tools (freely available for immediate use), our project addressed the need for consolidated guidance and created new materials for PRO implementation planning. We identified seven important lessons that, while common to technology implementation, are especially critical in PRO implementation.
To determine whether the Society for Healthcare Epidemiology of America (SHEA) and the Infectious Diseases Society of America (IDSA) Clostridioides difficile infection (CDI) severity criteria adequately predicts poor outcomes.
Retrospective validation study.
Setting and participants:
Patients with CDI in the Veterans’ Affairs Health System from January 1, 2006, to December 31, 2016.
For the 2010 criteria, patients with leukocytosis or a serum creatinine (SCr) value ≥1.5 times the baseline were classified as severe. For the 2018 criteria, patients with leukocytosis or a SCr value ≥1.5 mg/dL were classified as severe. Poor outcomes were defined as hospital or intensive care admission within 7 days of diagnosis, colectomy within 14 days, or 30-day all-cause mortality; they were modeled as a function of the 2010 and 2018 criteria separately using logistic regression.
We analyzed data from 86,112 episodes of CDI. Severity was unclassifiable in a large proportion of episodes diagnosed in subacute care (2010, 58.8%; 2018, 49.2%). Sensitivity ranged from 0.48 for subacute care using 2010 criteria to 0.73 for acute care using 2018 criteria. Areas under the curve were poor and similar (0.60 for subacute care and 0.57 for acute care) for both versions, but negative predictive values were >0.80.
Model performances across care settings and criteria versions were generally poor but had reasonably high negative predictive value. Many patients in the subacute-care setting, an increasing fraction of CDI cases, could not be classified. More work is needed to develop criteria to identify patients at risk of poor outcomes.
Self-monitoring biases and overconfidence in incorrect judgments have been suggested as playing a role in schizophrenia spectrum disorders. Little is known about whether self-monitoring biases may contribute to early risk factors for psychosis. In this study, action self-monitoring (i.e., discrimination between imagined and performed actions) was investigated, along with confidence in judgments among ultra-high risk (UHR) for psychosis individuals and first-episode psychosis (FEP) patients.
Thirty-six UHR for psychosis individuals, 25 FEP patients and 33 healthy controls (CON) participated in the study. Participants were assessed with the Action memory task. Simple actions were presented to participants verbally or non-verbally. Some actions were required to be physically performed and others were imagined. Participants were asked whether the action was presented verbally or non-verbally (action presentation type discrimination), and whether the action was performed or imagined (self-monitoring). Confidence self-ratings related to self-monitoring responses were obtained.
The analysis of self-monitoring revealed that both UHR and FEP groups misattributed imagined actions as being performed (i.e., self-monitoring errors) significantly more often than the CON group. There were no differences regarding performed actions as being imagined. UHR and FEP groups made their false responses with higher confidence in their judgments than the CON group. There were no group differences regarding discrimination between the types of actions presented (verbal vs non-verbal).
A specific type of self-monitoring bias (i.e., misattributing imagined actions with performed actions), accompanied by high confidence in this judgment, may be a risk factor for the subsequent development of a psychotic disorder.
Disturbed sleep and activity are prominent features of bipolar disorder type I (BP-I). However, the relationship of sleep and activity characteristics to brain structure and behavior in euthymic BP-I patients and their non-BP-I relatives is unknown. Additionally, underlying genetic relationships between these traits have not been investigated.
Relationships between sleep and activity phenotypes, assessed using actigraphy, with structural neuroimaging (brain) and cognitive and temperament (behavior) phenotypes were investigated in 558 euthymic individuals from multi-generational pedigrees including at least one member with BP-I. Genetic correlations between actigraphy-brain and actigraphy-behavior associations were assessed, and bivariate linkage analysis was conducted for trait pairs with evidence of shared genetic influences.
More physical activity and longer awake time were significantly associated with increased brain volumes and cortical thickness, better performance on neurocognitive measures of long-term memory and executive function, and less extreme scores on measures of temperament (impulsivity, cyclothymia). These associations did not differ between BP-I patients and their non-BP-I relatives. For nine activity-brain or activity-behavior pairs there was evidence for shared genetic influence (genetic correlations); of these pairs, a suggestive bivariate quantitative trait locus on chromosome 7 for wake duration and verbal working memory was identified.
Our findings indicate that increased physical activity and more adequate sleep are associated with increased brain size, better cognitive function and more stable temperament in BP-I patients and their non-BP-I relatives. Additionally, we found evidence for pleiotropy of several actigraphy-behavior and actigraphy-brain phenotypes, suggesting a shared genetic basis for these traits.
Prescribers who wrote at least 1 antibiotic prescription filled at a retail pharmacy in Tennessee in 2016.
Multivariable logistic regression, including prescriber gender, birth decade, specialty, and practice location, and patient gender and age group, to determine the association with high prescribing.
In 2016, 7,949,816 outpatient oral antibiotic prescriptions were filled in Tennessee: 1,195 prescriptions per 1,000 total population. Moreover, 50% of Tennessee’s outpatient oral antibiotic prescriptions were written by 9.3% of prescribers. Specific specialties and prescriber types were associated with high prescribing: urology (odds ratio [OR], 3.249; 95% confidence interval [CI], 3.208–3.289), nurse practitioners (OR, 2.675; 95% CI, 2.658–2.692), dermatologists (OR, 2.396; 95% CI, 2.365–2.428), physician assistants (OR, 2.382; 95% CI, 2.364–2.400), and pediatric physicians (OR, 2.340; 95% CI, 2.320–2.361). Prescribers born in the 1960s were most likely to be high prescribers (OR, 2.574; 95% CI, 2.532–2.618). Prescribers in rural areas were more likely than prescribers in all other practice locations to be high prescribers. High prescribers were more likely to prescribe broader-spectrum antibiotics (P < .001).
Targeting high prescribers, independent of specialty, degree, practice location, age, or gender, may be the best strategy for implementing cost-conscious, effective outpatient antimicrobial stewardship interventions. More information about high prescribers, such as patient volumes, clinical scope, and specific barriers to intervention, is needed.
Antimicrobial stewardship improves patient care and reduces antimicrobial resistance, inappropriate use, and adverse outcomes. Despite high-profile mandates for antimicrobial stewardship programs across the healthcare continuum, descriptive data, and recommendations for dedicated resources, including appropriate physician, pharmacist, data analytics, and administrative staffing support, are not robust. This review summarizes the current literature on antimicrobial stewardship staffing and calls for the development of minimum staffing recommendations.
Cover crops (CCs) play an important role in integrated weed management. Data necessary to evaluate the role of CCs in weed management at the watershed scale with topographic positions are lacking. We evaluated the effects of cereal rye and hairy vetch CCs on weed suppression at different topographic positions (shoulder, backslope, and footslope) at a watershed scale. Watersheds with a CC treatment followed a crop rotation of corn–cereal rye–soybean–hairy vetch, whereas watersheds without a CC (no-CC) had a crop rotation of corn–winter fallow–soybean–winter fallow. A negative relationship was present between CCs and weed biomass at the shoulder, backslope, and footslope topographic landscape positions, with R2 values of 0.40, 0.48, and 0.50, respectively. In 2016, a cereal rye CC reduced weed biomass 46% to 50% at footslope and shoulder positions compared to no CC. In 2018, a cereal rye CC reduced weed biomass between 52% and 85% at all topographic positions in CC treatment watersheds compared to no-CC watersheds. Hairy vetch in 2017 reduced weed biomass 62% to 72% at footslope and shoulder topographic positions in CC watersheds compared to no-CC. The C:N ratio of weed biomass in CC treatment watersheds was generally higher compared to watersheds without CCs. In this study, several significant interactions were found between the topographic positions and CC treatments. Cover crop–induced weed suppression at different topographic positions can lead to developing better site-specific weed control strategies. Therefore, CC interactions with topography, weed germination potential, and the role of soil moisture at the watershed scale should be further evaluated.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
In this study, we examine how the Guri catfish Genidens genidens uses estuarine and freshwater habitats along the largest South American coastal lagoon, through the chemical analysis of otoliths and microscopic analysis of gonads. Chemical composition (Sr:Ca) of otolith edges allowed distinguishing between individuals who used the estuarine or freshwater compartments of the lagoon. The analysis of core-to-edge chemical profiles of each individual otolith revealed that the population may present two different patterns of habitat use along the lagoon. The ‘type 1’ pattern (89.5%) includes fish who appear to have been born in estuarine waters, whereas ‘type 2’ (9.5%) includes those fish born in fresh water. Nevertheless, juveniles from both patterns appear to migrate to estuarine waters. The gonad analysis shows G. genidens may reproduce in fresh water, as nearly 57% of all sampled fish were found to spawn in the freshwater portion of the lagoon. Also, the otolith core of many adult fish presented freshwater signatures, thus suggesting consistent fresh water use during early life. Our findings based on otolith and gonadal analyses challenge the previous classification of G. genidens as an estuarine resident. Rather, our results allow the suggestion that this species should be placed in the ‘estuarine and fresh water’ guild, which includes both fish completing their life cycles within the estuary and fish who consistently use freshwater habitats.