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Epilepsy is one of the most common serious brain illness, with symptoms influenced by multiple risk factors and a strong genetic predisposition, rather than having a single expression and cause¹. Neuropsychiatric symptoms in epilepsy can encompass manifestations such as mood alterations, anxiety, sleep disturbances, psychosis, and behavioral disorders. While the motor and sensory manifestations of epileptic seizures are widely recognized, neuropsychiatric symptoms accompanying epilepsy are often underestimated. Therefore, it is essential to understand the most prevalent epidemiological profile of these patients to improve the diagnosis and management of these symptoms.
Objectives
Our goal was to evaluate the neuropsychiatric behavior of epilepsy patients in Brazilian over the past 3 years through hospitalization data in order to outline an epidemiological and behavioral profile.
Methods
A cross-sectional, descriptive, retrospective, and quantitative study was conducted on hospitalizations of individuals simultaneously diagnosed with epilepsy, schizotypal and delusional disorders, and mood disorders in all five regions of Brazil (South, Southeast, Midwest, North, and Northeast) between February 2020 and December 2022. Data from January 2020 were not available. The data used were collected through the Department of Health Informatics of the Brazilian Unified Health System (DATASUS) in the “Hospital Information System of SUS” section, gathering information regarding the nature of care, age range, gender, and ethnicity of the patients.
Results
The analysis covers the years 2020 to 2022, totaling 503,045 hospitalizations. In 2022, the highest number of cases occurred (≈ 37.55%), followed by 2021 (≈ 33.62%) and 2020 (≈ 28.81%). Urgent hospitalizations represented ≈ 90.85% of the total. The most affected age group was 30 to 39 years old (≈ 18.30%). Men were more affected than women (≈ 52.03% and ≈ 47.96%, respectively), and Caucasians accounted for ≈ 36.07% of the hospitalizations. The average length of stay was 19.1 days, and the mortality rate was 1.4%.
Conclusions
Thus, there is a gradual and annual increase in the number of hospitalizations during the observed period. While there is a minimal disparity between the affected genders, it is evident that the profile of male, caucasian, and adult patients is the most prevalent. Moreover, the predominantly urgent nature of hospitalizations points to an alarming scenario regarding this issue. From the analysis of the data obtained in the study, there is a clear need for interventions capable of reducing the prevalence of hospitalizations for neuropsychiatric symptoms in epilepsy patients in Brazil.
Neuropsychiatric disorders are the leading cause of disability worldwide, as seen in cases such as depression, anxiety, bipolar mood disorder and schizophrenia, which can be developed or exacerbated by the use of psychoactive substances. Most mental disorders have an early onset, often leading to early and/or permanent disability, increasing the need and cost of healthcare. Therefore, it is necessary to improve the identification of the epidemiological profile of these cases in the South of Brazil in order to enhance the diagnosis and reduce the costs associated with managing these disorders.
Objectives
The present study aimed to analyze statistical data regarding hospitalizations related to mental disorders caused by the use of psychoactive substances and alcohol in the southern region of Brazil, highlighting the pathological scenario and identifying the most prevalent profiles of these disorders in this region.
Methods
A cross-sectional, descriptive, retrospective, and quantitative study was conducted on hospitalizations of individuals diagnosed with mental and behavioral disorders due to the use of psychoactive substances and alcohol in the states of the Southern region of Brazil (Paraná, Santa Catarina, and Rio Grande do Sul) between February 2020 and December 2022. Data of January 2020 were not available. The data used were collected through the Department of Health Informatics of the Brazilian Unified Health System (DATASUS) in the “Hospital Information System of SUS” section, gathering information regarding the nature of the care, age range, gender, and ethnicity of the patients.
Results
The study covers the years 2020 to 2022, indicating a total of 81,608 hospitalizations, with the year 2022 having the highest number of cases (≈ 37.13%), followed by 2021 (≈ 33.30%) and 2020 (≈ 29.55%). The states with the highest number of hospitalizations were Rio Grande do Sul (≈ 54.90%), Paraná (≈ 29.29%), and Santa Catarina (≈ 15.79%). Urgent hospitalizations accounted for ≈ 87.29% of the total. The most affected age group was 30 to 39 years old (≈ 25.61%). Men were more affected than women (≈ 81.70% and ≈ 18.28%, respectively). Caucasians accounted for ≈ 64.29% of the hospitalizations. The average length of stay was 20.8 days, and the mortality rate was 0.32%.
Conclusions
There is a clear increase in the number of hospitalizations related to mental disorders caused by the use of psychoactive substances in the period from 2020 to 2022 in the southern region of Brazil, with the highest number of cases in the state of Rio Grande do Sul. The most affected population consisted of Caucasian men aged 30 to 39 years old. Furthermore, these results may be related to the increasing trend of psychoactive substance use among the Brazilian population and also the COVID-19 pandemic, which led to a period of underreporting due to social isolation.
In recent years, mental health has gained prominence in public health, prompting thorough investigations into psychiatric condition trends. This study conducts a comprehensive epidemiological analysis of hospitalizations for Schizophrenia, Schizotypal, and Delirium Disorders in Rio Grande do Sul (RS) over the past five years. By revealing these patterns, it enhances our understanding of regional mental health dynamics and offers insights for intervention strategies, resource planning, and improved mental healthcare. The ultimate goal is to advance more effective and accessible mental healthcare in RS and beyond.
Objectives
This study aims to analyze the prevalence and epidemiological profile of hospitalizations due to psychiatric disorders to assist in the diagnosis and outcome of affected patients.
Methods
A cross-sectional, descriptive, retrospective, and quantitative study was conducted regarding hospitalizations for Schizophrenia, Schizotypal Disorders, and Delirium in the state of RS between January 2018 and November 2022. Data were collected from the Department of Informatics of the Brazilian Unified Health System (DATASUS) in the “Hospital Information System of SUS” section, focusing on the nature of care, age group, gender, and ethnicity of the patients. The information was aggregated over the five-year period based on the four mentioned descriptors and subsequently analyzed to establish a profile of hospitalizations during that period.
Results
The analysis spans from 2018 to 2022, encompassing a total of 28,345 hospitalizations. In 2019, there was the highest number of cases (22.21%), followed by 2018 (21.08%). Urgent care admissions constituted 85.34% of the total. The age group most affected was 35 to 39 years (11.8%). Men were more affected than women (60.18%), and the majority of hospitalizations were among the Caucasian ethnicity (75.12%). The average length of stay was 23.7 days, and the mortality rate stood at 0.26%.
Conclusions
The increasing trend in hospitalizations, peaking in 2019, highlights the need for preventive measures. Urgent admissions (85.34%) underscore the demand for accessible mental health resources. Men in the 35 to 39 age group are disproportionately affected, suggesting specific risk factors. The predominance of Caucasian ethnicity emphasizes the need for culturally sensitive care. A longer average length of stay (23.7 days) underscores treatment complexity, while a low mortality rate (0.26%) signals effective medical care. In essence, these findings inform tailored mental health policies to enhance service quality and prioritize patient-centered approaches.
A dynamical understanding of the physical process of surface gravity wave breaking remains an unresolved problem in fluid dynamics. Conceptually, breaking can be described by inception and onset, where breaking inception is the initiation of unknown irreversible processes within a wave crest that precede the visible manifestation of breaking onset. In the search for an energetic indicator of breaking inception, we use an ensemble of non-breaking and breaking crests evolving within unsteady wave packets simulated in a numerical wave tank to investigate the evolution of each term in the kinetic energy balance equation. We observe that breaking onset is preceded by around one quarter of a wave period by a rapid increase in the rate of convergence of kinetic energy that triggers an irreversible acceleration of the kinetic energy growth rate. This energetic signature, which is present only for crests that subsequently break, arises when the kinetic energy growth rate exceeds a critical threshold. At this point the additional kinetic energy convergence cannot be offset by converting excess kinetic energy to potential energy or by dissipation through friction. Our results suggest that the ratio of the leading terms of the kinetic energy balance equation at the time of this energetic signature is proportional to the strength of the breaking crest. Hence this energetic inception point both predicts the occurrence of breaking onset and indicates the strength of the breaking event.
We sought to determine whether an electronic hand hygiene (HH) system could monitor HH compliance at similar rates to direct human observation.
Methods:
This 4-year proof-of-concept study was conducted in an intensive care unit (ICU) of a private tertiary-care hospital in São Paulo, Brazil, where electronic HH systems were installed in 2 rooms. HH compliance was reported respectively using direct observation and electronic counter devices with an infrared system for detecting HH opportunities.
Results:
In phase 1, HH compliance by human observers was 56.3% (564 of 1,001 opportunities), while HH compliance detected by the electronic observer was 51.0% (515 of 1,010 opportunities). In phase 2, human observers registered 484 HH opportunities with a HH compliance rate of 64.7% (313 of 484) versus 70.6% (346 of 490) simultaneously detected by the electronic system. In addition, an enhanced HH electronic system monitored activity 24 hours per day and HH compliance without the presence of a human observer was 40.3% (10,642 of 26,421 opportunities), providing evidence for the Hawthorne effect.
Conclusions:
The electronic HH monitoring system had good correlation with human HH observation, but compliance was remarkably lower when human observers were not present due to the Hawthorne effect (25%–30% absolute difference). Electronic monitoring systems can replace direct observation and can markedly reduce the Hawthorne effect.
Schizophrenia is a severe mental illness that requires long-term treatment with antipsychotics and the intramuscular (IM) long-acting injectable (LAI) formulations may enhance treatment adherence. Some antipsychotics have been associated with enuresis, including atypical antipsychotics such as risperidone(6.2%), quetiapine(6.7%), olanzapine (9.6% ) and clozapine (20.7%) [1]. Although oral paliperidone has been related to urinary incontinence, there is only 1 report of urinary incontinence linked to monthly paliperidone palmitate [2]. [1] Harrison-Woolrych, M., Skegg, K., Ashton, J., Herbison, P., Skegg, D.C., 2011. Nocturnal enuresis in patients taking clozapine, risperidone, olanzapine and quetiapine: comparative cohort study. British Journal of Psychiatry 199, 140–144. doi:10.1192/bjp.bp.110.087478 [2] Karslıoǧlu, E.H., Özalp, E., Çayköylü, A., 2016. Paliperidone Palmitate-induced Urinary Incontinence: A Case Report. Clinical Psychopharmacology and Neuroscience 14, 96–100. doi:10.9758/cpn.2016.14.1.96
Objectives
To establish an association between paliperidone palmitate and enuresis.
Methods
Case report and a narrative review of the literature.
Results
The patient was a 25-year-old healthy man when he was diagnosed with schizophrenia. Doctors prescribed paliperidone palmitate (LAI) 200mg monthly and he started to complain of enuresis. He was clearly suffering with this unpleasant and embarrassing adverse effect so the LAI was reduced to 150mg. Enuresis remained, so it was prescribed oxybutynin 20 mg/day and the patient improved.
Conclusions
We reported a case in which enuresis is likely to be associated with high-dose paliperidone LAI (with no clinical evidence of an organic cause). To treat it, the most effective strategy was oxybutynin 20 mg/day. This case is also important to show the impact of this symptom, which is not actively investigated.
Most hand hygiene (HH) intervention studies use a quasi-experimental design, are primarily uncontrolled before-and-after studies, or are controlled before-and-after studies with a nonequivalent control group. Well-funded studies with improved designs and HH interventions are needed.
Objectives:
To evaluate healthcare worker (HCW) HH compliance with alcohol-based hand rub (ABHR) through direct observation (human observer), 2 electronic technologies, a radio frequency identification (RFID) badge system, and an invasive device sensor.
Methods:
In our controlled experimental study, 2,269 observations were made over a 6-month period from July 1 to December 30, 2020, in a 4-bed intensive care unit. We compared HH compliance between a basic feedback loop system with RFID badges and an enhanced feedback loop system that utilized sensors on invasive devices.
Results:
Real-time feedback by wireless technology connected to a patient’s invasive device (enhanced feedback loop) resulted in a significant increase in HH compliance (69.5% in the enhanced group vs 59.1% in the basic group; P = .0001).
Conclusion:
An enhanced feedback loop system connected to invasive devices, providing real-time alerts to HCWs, is effective in improving HH compliance.
Within-year variation in infection is a ubiquitous feature of natural populations, but is determined by a complex interplay of environmental, parasitological and host factors. At the same time, co-infection is the norm in the wild. Longitudinal dynamics of co-infecting parasites may therefore be further complicated by covariation across multiple parasites. Here, we used fecal parasite egg and oocyst counts collected repeatedly from individually marked wild Soay sheep to investigate seasonal dynamics of six gastrointestinal parasite groups. Prevalence and abundance tended to be higher in spring and summer, and abundance was higher in lambs compared to adults. We found that within-year variation in highly prevalent strongyle nematode counts was dependent on adult reproductive status, where reproductive ewes had distinct dynamics compared to males and barren ewes. For similarly prevalent coccidia we found an overall peak in oocyst counts in spring but no differences among males, barren and pregnant ewes. Using multivariate mixed-effects models, we further show that apparent positive correlation between strongyle and coccidia counts was driven by short-term within-individual changes in both counts rather than long-term among-individual covariation. Overall, these results demonstrate that seasonality varies across demographic and parasite groups and highlight the value of investigating co-infection dynamics over time.
This work aimed to investigate the effects of early progeny exposure to methylglyoxal (MG), programming for metabolic dysfunction and diabetes-like complications later in life. At delivery (PN1), the animals were separated into two groups: control group (CO), treated with saline, and MG group, treated with MG (20 mg/kg of BW; i.p.) during the first 2 weeks of the lactation period. In vivo experiments and tissue collection were done at PN90. Early MG exposure decreased body weight, adipose tissue, liver and kidney weight at adulthood. On the other hand, MG group showed increased relative food intake, blood fructosamine, blood insulin and HOMA-IR, which is correlated with insulin resistance. Besides, MG-treated animals presented dyslipidaemia, increased oxidative stress and inflammation. Likewise, MG group showed steatosis and perivascular fibrosis in the liver, pancreatic islet hypertrophy, increased glomerular area and pericapsular fibrosis, but reduced capsular space. This study shows that early postnatal exposure to MG induces oxidative stress, inflammation and fibrosis markers in pancreas, liver and kidney, which are related to metabolic dysfunction features. Thus, nutritional disruptors during lactation period may be an important risk factor for metabolic alterations at adulthood.
The Roca San Miguel (RSM) archaeological site was occupied during Mousterian times. Here we present a geoarchaeological and paleoenvironmental reconstruction of the site. Five stratigraphic units (A to E) formed by different archaeological levels are identified. Three optically stimulated luminescence (OSL) ages show that Unit A dates to between 169.6 ± 9.1 and 151.9 ± 11.1 ka, during the penultimate glacial period (PGP), and contains numerous signs of recurring hearths. Unit B is unexcavated. Unit C dates to between 118.9 ± 11.5 and 103.4 ± 6.9 ka (late Eemian–marine isotope stage (MIS) 5d) and shows an abundance of lithic remains as well as some faunal elements. Unit C is covered by Unit D, which incorporates materials moved downslope, and is dated at 81.2 ± 4.7 ka. These OSL ages concur with U/Th ages (129.3 ± 1.5 and 123.6 ± 0.6 ka) derived from a flowstone covered by both -C and D- post-flowstone units. Finally, Unit E covers the archaeological site, which was partially eroded during MIS2. The robust and well-constrained chronology of the RSM site and surroundings enables the establishment of its evolutionary model from the PGP to the last glacial cycle. The RSM site is the oldest Neanderthal occupation accurately dated in the Pre-Pyrenean region.
To identify drugs that were administered off label to hospitalized patients with suspected coronavirus disease 2019 (COVID-19) and to identify adverse drug reactions (ADRs) and drug–drug interactions associated with these therapies.
Methods:
This case–control study was conducted in a Brazilian hospital from March to April 2020 among patients with suspected COVID-19, comparing those with positive severe acute respiratory coronavirus virus 2 (SARS-CoV-2) reverse-transcriptase polymerase chain reaction (RT-PCR) results and those with negative results.
Results:
The most commonly used medications in both groups were azithromycin and hydroxychloroquine. There was a significantly higher prevalence of reactions among patients with positive RT-PCR for SARS-CoV-2 (48.5% vs 28.8%; P = .008) in the propensity score–matched cohort, and the most commonly reported ADRs among these patients were diarrhea (43.8%), elevated liver enzymes (31.3%), and nausea and vomiting (29.7%).
Conclusions:
Our data demonstrate that ADRs and drug–drug interactions are common with off-label treatments for COVID-19.
The identification of protection factors regarding older adults’ mental health is essential. Self-compassion, the capacity to be kind towards the self during challenging times, may be one such factor. Although still scarce, some research in this field has already been conducted with older adults. Our research question was the following: what is currently known about the role of self-compassion in the psychological (mal)adjustment of older adults?
Objectives:
To review any study designs, in any setting, where self-compassion and any indicators of psychological (mal)adjustment were assessed in participants aged ≥60 years.
Design:
A scoping review of English, Portuguese, and Spanish published and unpublished materials, using the EBSCOhost Research and PubMed databases and reference lists. Search terms included self-compassion, self compassion, older adults, elderly, seniors, and geriatrics. After screening and selection of the studies, we charted the relevant data.
Results:
Eleven published studies (2012–2018) were reviewed. Self-compassion was associated with, and a predictor of, diverse mental health indicators in older adults. Self-compassion was also associated with indicators of physical health, moderated the relationship between physical health indicators and mental health indicators, and mediated the relationship between diverse mental health indicators. Results were obtained with participants of different nationalities and age. All studies had a cross-sectional design, and most studies recruited well-functioning community residents.
Conclusions:
Self-compassion is beneficial for the psychological adjustment of older adults and may also benefit their biological functioning. Self-compassion seems particularly relevant for those experiencing more negative life events. Studies with more robust methodologies are needed in order to replicate these findings.
There is a substantial proportion of patients who drop out of treatment before they receive minimally adequate care. They tend to have worse health outcomes than those who complete treatment. Our main goal is to describe the frequency and determinants of dropout from treatment for mental disorders in low-, middle-, and high-income countries.
Methods
Respondents from 13 low- or middle-income countries (N = 60 224) and 15 in high-income countries (N = 77 303) were screened for mental and substance use disorders. Cross-tabulations were used to examine the distribution of treatment and dropout rates for those who screened positive. The timing of dropout was examined using Kaplan–Meier curves. Predictors of dropout were examined with survival analysis using a logistic link function.
Results
Dropout rates are high, both in high-income (30%) and low/middle-income (45%) countries. Dropout mostly occurs during the first two visits. It is higher in general medical rather than in specialist settings (nearly 60% v. 20% in lower income settings). It is also higher for mild and moderate than for severe presentations. The lack of financial protection for mental health services is associated with overall increased dropout from care.
Conclusions
Extending financial protection and coverage for mental disorders may reduce dropout. Efficiency can be improved by managing the milder clinical presentations at the entry point to the mental health system, providing adequate training, support and specialist supervision for non-specialists, and streamlining referral to psychiatrists for more severe cases.
Factitious disorders (FD) are characterized by intentional production of either physical, psychological or mixed symptoms that mimic various clinical syndromes, with no apparent advantage for the individual concerned other than allowing him to assume the sick role. Large body of work has been accumulated on FD, but the majority of published data deal with the physical variant of the disease, with comparable few reports on psychiatric FD. Although there are many different presentations for psychiatric FD, the factitious psychosis subset justifies particular attention. Factitious psychosis may be prodromic of a genuine chronic psychosis, usually in the context of a personality disorder. Published data shows Munchausen psychosis, a severe subset of FD psychosis, with a prevalence of 0.25% of all inpatient admissions and global FD psychosis attaining 4.1% of all diagnosed psychoses, generally with a poor prognosis.
The scantiness of studies on the subject of psychiatric FD and factitious psychosis in particular, despite its significant prevalence, coupled with the fact that its recognition embarks on a radically different approach compared with the physical variant, stresses the need for case reporting.
We present four clinical cases with discussion of the underlying pathology and outcome, and a systematic review of the literature of FD psychosis case reports. This is followed by further discussion addressing the recognition of factitious psychosis, its etiological contributing factors, management, effects on staff and diagnostic criteria.
There is a need to address vulnerable carers in schizophrenia and severe mental illness, although research has not yet defined feasible risk assessment routines. Caregiver needs must be sought and targeted instead of blindly delivering previously defined programs. In Portugal, where psychoeducational family work has been scarcely implemented/evaluated, the Families of Psychotic Patients(FAPS) Project is now running in Lisbon. It consists of a prospective study of caregivers, which will be followed in time by a group intervention study for a defined sub-sample.
Methods:
Caregivers' assessments (baseline) include the Involvement Evaluation Questionnaire, the GHQ, the Social Network Questionnaire and a schedule including questions on intervention needs/adherence). Patients are given the BPRS, WHO-DAS II and GAF. We present preliminary data concerning baseline assessments of a first cohort of the prospective survey (n=70). A convenience sample of primary caregivers to patients with schizophrenia, schizo-affective or delusional disorders (ICD-10) was considered.
Results:
Key-relatives (age 59.4±13.1 yrs) were mostly female (87%). Burden was evident (especially IEQ worrying 18.9±5.4). 31,4 % scored GHQ+, while needs for family work were not invariably expressed, in discrepancy with interviewers's expectations.
Conclusions:
Caregiver burden and psychological distress do not imply adherence to family interventions (either in relative groups or behaviour family therapy format). Moreover, some of the most distressed carers seem to be the hardest to recruit.
These considerations must be checked at follow-up with the whole sample and warrant further research. Apparently, one should tailor family intervention programs to each family according to prior detailed assessments.
Exhibitionistic disorder may be present when there is sexual arousal from the exposure of one's genitals to an unsuspecting and nonconsenting person. This disorder prevalence is unknown but we know it is highly unusual in females. It generally starts at adolescence and its course is likely to vary with age. There are temperamental and environmental risk factors.
Most of what we know about exhibitionistic disorder is largely based on research with individuals convicted for criminal acts involving genital exposure, and this may represent an important bias. From a clinical case of exhibitionism, the authors intend to review this type of paraphilia from an historical, conceptual and etiologic point of view.
Objective
To review the concept behind this diagnosis and its evolution, the comprehensive theories that attempt to justify and frame it, as well as the type of intervention currently considered to be the state of the art.
Methods
Patient's observation and assessment, along with an extensive review of the relevant literature.
Conclusions
Starting from a real clinical case, the authors present a general theoretical review on the subject.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Within psychiatry, sexology is a very particular area of expertise both by the nature and specificity of its diagnosis, as by the various difficulties and challenges their patients place. Sexology is a sub-specialty niche, but also a vast universe that covers such diverse conditions as paraphilia, gender dysphoria or sexual dysfunction. The sexology consultation of Santa Maria Hospital (HSM) is one of the biggest centers specialized in sexual disorders in the country. Consultations depend on the collaboration of a sexologist psychiatrist and psychiatry residents in close connection with endocrinology, urology and plastic surgery services.
Objective
We intend to conduct a characterization of the population observed in the HSM sexology consultation, in a period of 2 years, from the analyses of different general and diagnosis-specific relevant variables.
Methods
We intent to make a descriptive analysis of the population that attended the sexology consultation over the last 2 years. The sample study refers to all patients who have been specifically referred to sexology department or that directly requested access to this consultation. Data will be collected from medical computer records.
Results
Through systematic evaluation of different variables we can possibly conclude by some putative associations. A comprehensive characterization of this particular population is a possible method for a better and deeper insight on the diagnosis itself.
Conclusions
The purpose of this work is to increase peers’ sensitivity both to sexology and to the patients sexology serves.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Although extrafloral nectar (EFN) is a key food resource for arboreal ants, its role in structuring ground-nesting ant communities has received little attention, despite these ants also being frequent EFN-attendants. We investigated the role of EFN as a driver of the spatial structure of ground-nesting ant communities occurring in dry forest in north-eastern Brazil. We examined the effects on this relationship of two global drivers of biodiversity decline, chronic anthropogenic disturbance and climate change (through decreasing rainfall). We mapped EFN-producing plants and ant nests in 20 plots distributed along independent gradients of disturbance and rainfall. We categorized ant species into three types according to their dependence on EFN: heavy users, occasional users and non-users. We found a strong relationship between ant dependence on EFN and nest proximity to EFN-producing plants: heavy-users (mean distance 1.1 m) nested closer to EFN-producing plants than did occasional users (1.7 m), which in turn nested closer to EFN-producing plants than did non-users (2.3 m). Neither disturbance nor rainfall affected the proximity of heavy-user nests to EFN-producing plants. Our study shows for the first time that EFN is a key driver of the spatial structure of entire communities of ground-nesting ants.
Cephalopods are important prey in the diet of top predators, such as marine mammals and seabirds. However, detailed information on their trophic relationships in the Patagonian marine ecosystem is scarce, including those cephalopod species with commercial interest. The aims of this study were to evaluate the composition of the cephalopod component in the diet of Otaria byronia and determine the habitat use and trophic levels of their main cephalopod prey by measuring the stable isotopic signature of cephalopod beaks. Between May 2005 and February 2009, fresh faecal samples were collected from two sea lions rookeries in San Matias Gulf. Cephalopods occurred in 39.4% of the 1112 samples collected during the whole period of study. The dominant prey species was Octopus tehuelchus, which occurred in 45.8% of scats containing cephalopod remains, and represented 58.7% in terms of numerical abundance and 52.0% in mass of cephalopods consumed. The second species most consumed was the myopsid Doryteuthis gahi. The significant higher δ15N values of O. tehuelchus beaks in comparison with those of D. gahi showed that these two species have different trophic levels while occupying similar habitat (δ13C values) in neritic waters of the Patagonian shelf.