Intermittent Fasting as a Potential Therapeutic Instrument for Major Depression Disorder: A Systematic Review of Clinical and Preclinical Studies.

Recent studies have reported positive effects of Intermittent Fasting (IF) on metabolic parameters, cognition, and mood. However, regarding depressive symptoms, the effect of IF is not clear. The purpose of this review was to assess the available evidence on IF interventions for depression in both clinical and preclinical studies. Of the 23 included studies, 15 were performed on humans and 8 on animal models. The studies on rodents suggested that IF acts as a circadian regulator, improving neurotransmitter availability and increasing the levels of neurotrophic factors in the brain. However, the investigations on humans mainly evaluated healthy volunteers and showed a great heterogeneity regarding both the IF regimen studied and the observed effects on mood. Most available clinical trials have specific limitations, such as small sample sizes and uncontrolled designs. A comprehensive systematic review was conducted on five databases, PubMed, Cochrane, the Central Register of Controlled Trials, Web of Science databases, BVS and Scopus, identifying 23 relevant studies up to 6 October 2022. IF has potentially relevant physiological effects for the treatment of mood disorders, but better designed studies and controlled evaluations are needed to evaluate its efficiency in the treatment of major depression.

Mapping language with resting-state functional magnetic resonance imaging: A study on the functional profile of the language network.

Resting-state functional magnetic resonance imaging (rsfMRI) is a promising technique for language mapping that does not require task-execution. This can be an advantage when language mapping is limited by poor task performance, as is common in clinical settings. Previous studies have shown that language maps extracted with rsfMRI spatially match their task-based homologs, but no study has yet demonstrated the direct participation of the rsfMRI language network in language processes. This demonstration is critically important because spatial similarity can be influenced by the overlap of domain-general regions that are recruited during task-execution. Furthermore, it is unclear which processes are captured by the language network: does it map rather low-level or high-level (e.g., syntactic and lexico-semantic) language processes? We first identified the rsfMRI language network and then investigated task-based responses within its regions when processing stimuli of increasing linguistic content: symbols, pseudowords, words, pseudosentences and sentences. The language network responded only to language stimuli (not to symbols), and higher linguistic content elicited larger brain responses. The left fronto-parietal, the default mode, and the dorsal attention networks were examined and yet none showed language involvement. These findings demonstrate for the first time that the language network extracted through rsfMRI is able to map language in the brain, including regions subtending higher-level syntactic and semantic processes.

Temporal reliability of ultra-high field resting-state MRI for single-subject sensorimotor and language mapping.

Resting-state fMRI is a well-suited technique to map functional networks in the brain because unlike task-based approaches it requires little collaboration from subjects. This is especially relevant in clinical settings where a number of subjects cannot comply with task demands. Previous studies using conventional scanner fields have shown that resting-state fMRI is able to map functional networks in single subjects, albeit with moderate temporal reliability. Ultra-high resolution (7T) imaging provides higher signal-to-noise ratio and better spatial resolution and is thus well suited to assess the temporal reliability of mapping results, and to determine if resting-state fMRI can be applied in clinical decision making including preoperative planning. We used resting-state fMRI at ultra-high resolution to examine whether the sensorimotor and language networks are reliable over time - same session and one week after. Resting-state networks were identified for all subjects and sessions with good accuracy. Both networks were well delimited within classical regions of interest. Mapping was temporally reliable at short and medium time-scales as demonstrated by high values of overlap in the same session and one week after for both networks. Results were stable independently of data quality metrics and physiological variables. Taken together, these findings provide strong support for the suitability of ultra-high field resting-state fMRI mapping at the single-subject level.

Chronic pain disrupts the reward circuitry in multiple sclerosis.

Pain commonly affects multiple sclerosis (MS) patients, and has the potential to become chronic and burden an already damaged central nervous system. Imaging studies are providing insights into brain restructuring associated with chronic pain and different chronic pain conditions seem to evoke distinct plasticity patterns. Our objective was to study the structural and functional brain changes of chronic neuropathic pain of MS. Employing structural and resting functional magnetic resonance imaging we compared MS patients with chronic central pain with MS patients without pain matched with respect to age, gender, subtype and duration of MS and disability. Mean duration of pain was 7.6 years. Comparing the pain and no-pain groups, brain functional default-mode network differences were found. There was decreased coactivation in the caudate nucleus and nucleus accumbens bilaterally. Also, for the relapsing-remitting subgroup of patients, grey matter thickness changes predominated in the pain group in the mesial region of the temporal lobes, caudate, putamen, thalami and the fronto-parietal cortex; in the group without pain, changes predominated in the frontopolar and orbitofrontal cortices and in the occipital areas. A dysfunction in the reward system in chronic pain of MS was found, particularly in the brain areas involved in its motivational aspects, as such probably reflecting the maladaptive physiology of chronic pain, and possibly the signature of pain in MS, in a disease where reward impairment seems to be already one of its features.

Functional transcranial Doppler: presymptomatic changes in Fabry disease.

BACKGROUND AND AIM: Cerebrovascular disease may progress asymptomatically in the early stages of Fabry disease (FD). Our aim was to test whether functional transcranial Doppler (fTCD) could provide useful data in the evaluation of these presymptomatic FD patients. METHODS: A cohort of 12 adult FD patients from families with the classical phenotype of the disease was evaluated with fTCD in the posterior cerebral artery. RESULTS: Compared to healthy controls, resting blood velocities were significantly lower in the FD cohort (p = 0.032 for systolic, p = 0.021 for diastolic). FTCD suggested a disturbed neurovascular coupling in the visual cortex of FD patients, with lower gain (p = 0.007) and rate time (p = 0.019). Men had a significantly higher attenuation (p = 0.013) and lower natural frequency (p = 0.046) than the heterozygous women. CONCLUSION: These data are the first to suggest that patients with FD may develop cortical vascular dysfunction in the territory of the posterior circulation, early in the natural history of the disease. If the present findings are confirmed in larger, prospective studies, fTCD will be useful for assessing stroke risk in as yet asymptomatic FD patients, improving preventive therapeutic management.

Differentiating Hypoglycemia Awareness Status from Hypoglycemia Experience in Tools for Measuring Impaired Awareness of Hypoglycemia.

Background: Developing technologies in real-time continuous glucose monitoring (CGM) are successfully reducing severe hypoglycemia (SH) in trials and clinical practice. Their impact on impaired awareness of hypoglycemia, a major risk factor for SH, is uncertain. Methods: The present study examined two scales for assessing hypoglycemia awareness status, the Gold score and the eight-item Minimally Modified Clarke Hypoglycemia Survey (MMCHS), commonly used in trials of CGM, in Portuguese-speaking adults with type 1 diabetes and conducted an exploratory factor analysis on MMCHS. Results: A bifactorial structure in MMCHS was revealed, with a clear distinction between items that measure SH experience and those that measure hypoglycemia awareness status. The latter is associated with the same risk for SH as the Gold score. Conclusions: We conclude that improvement in awareness scores by the MMCHS may reflect only a reduction in SH with no restoration of endogenous awareness, making the current literature consistent in evidence that CGM does not improve endogenous awareness and nonsensor supported protection from SH. This has implications for risk of SH when CGM is not being worn.

Consensus Recommendations of the Multiple Sclerosis Study Group and the Portuguese Neuroradiological Society for the Use of Magnetic Resonance Imaging in Multiple Sclerosis in Clinical Practice: Part 2.

INTRODUCTION: Magnetic resonance imaging is recognized as the most important diagnostic test in the diagnosis of multiple sclerosis, differential diagnosis and evaluation of progression/therapeutic response. However, to make optimal use of magnetic resonance imaging in multiple sclerosis, the use of a standard, reproducible and comparable imaging protocol is of uttermost importance. In this context, the Portuguese Society of Neuroradiology and the Group of Studies of Multiple Sclerosis, after a joint discussion, appointed a committee of experts to create recommendations adapted to the national reality on the use of magnetic resonance imaging in multiple sclerosis. This document represents the second part of the first Portuguese consensus recommendations on the use of magnetic resonance imaging in multiple sclerosis in clinical practice. MATERIAL AND METHODS: The Portuguese Society of Neuroradiology and the Group of Studies of Multiple Sclerosis, after discussing the topic in national meetings and after a working group meeting held in Figueira da Foz, May 2017, appointed a committee of experts that have developed several standard protocols on the use of magnetic resonance imaging on multiple sclerosis by consensus. The document obtained was based on the best scientific evidence and expert opinion. Portuguese multiple sclerosis consultants and departments of neuroradiology scrutinized and reviewed the consensus paper; comments and suggestions were considered. Standardized strategies of magnetic resonance imaging referral in clinical practice for diagnosis and follow-up of multiple sclerosis were published in the first part of this paper. RESULTS: We provide magnetic resonance imaging acquisition protocols regarding multiple sclerosis diagnostic and monitoring and the information to be included in the report for application across Portuguese healthcare institutions. CONCLUSION: We hope that these first Portuguese magnetic resonance imaging guidelines will contribute to optimize multiple sclerosis management and improve patient care in Portugal.

Introdução: A ressonância magnética é considerada o exame complementar mais importante para o diagnóstico de esclerose múltipla, seus diagnósticos diferenciais e avaliação da sua progressão/resposta terapêutica. No entanto, para um uso ótimo desta ferramenta na esclerose múltipla, é essencial a aplicação de um protocolo de imagem padronizado, reprodutível e comparável. Neste contexto, o Grupo de Estudos de Esclerose Múltipla e a Sociedade Portuguesa de Neurorradiologia, após discussão conjunta, designaram um comité de peritos para a criação de recomendações adaptadas à realidade nacional sobre a utilização da ressonância magnética na esclerose múltipla. Este documento corresponde à segunda parte das primeiras recomendações de consenso portuguesas sobre a utilização da ressonância magnética na esclerose múltipla na prática clínica. Material e Métodos: O Grupo de Estudos de Esclerose Múltipla e a Sociedade Portuguesa de Neurorradiologia após discussão do tema em reuniões de âmbito nacional e de uma reunião do grupo de trabalho que teve lugar na Figueira da Foz em maio de 2017, designaram um comité de peritos que elaboraram por método de consenso protocolos padronizados sobre o uso da ressonância magnética na esclerose múltipla. O documento teve como base a melhor evidência científica e a opinião dos peritos. Posteriormente, o documento foi enviado para escrutínio à maioria dos responsáveis de consulta de esclerose múltipla e dos departamentos de neurorradiologia; tendo sido considerados os seus comentários e sugestões. As estratégias padronizadas de referenciação imagiológica na prática clínica para o diagnóstico e seguimento da esclerose múltipla foram publicadas na primeira parte deste artigo. Resultados: Neste artigo são propostos os protocolos de aquisição de ressonância magnética adequados para o diagnóstico e monitorização da esclerose múltipla, bem como a informação a constar do relatório imagiológico, tendo em vista a sua aplicação nas várias instituições de saúde portuguesas. Conclusão: Os autores esperam que estas primeiras orientações portuguesas sobre a utilização da ressonância magnética na esclerose múltipla na prática clínica contribuam para otimizar a gestão desta patologia e melhorar o tratamento destes doentes em Portugal.

Identification of drought-responsive genes in roots of upland rice (Oryza sativa L).

BACKGROUND: Rice (Oryza sativa L.) germplasm represents an extraordinary source of genes that control traits of agronomic importance such as drought tolerance. This diversity is the basis for the development of new cultivars better adapted to water restriction conditions, in particular for upland rice, which is grown under rainfall. The analyses of subtractive cDNA libraries and differential protein expression of drought tolerant and susceptible genotypes can contribute to the understanding of the genetic control of water use efficiency in rice. RESULTS: Two subtractive libraries were constructed using cDNA of drought susceptible and tolerant genotypes submitted to stress against cDNA of well-watered plants. In silico analysis revealed 463 reads, which were grouped into 282 clusters. Several genes expressed exclusively in the tolerant or susceptible genotypes were identified. Additionally, proteome analysis of roots from stressed plants was performed and 22 proteins putatively associated to drought tolerance were identified by mass spectrometry. CONCLUSION: Several genes and proteins involved in drought-response, as well as genes with no described homologs were identified. Genes exclusively expressed in the tolerant genotype were, in general, related to maintenance of turgor and cell integrity. In contrast, in the susceptible genotype, expression of genes involved in protection against cell damage was not detected. Several protein families identified in the proteomic analysis were not detected in the cDNA analysis. There is an indication that the mechanisms of susceptibility to drought in upland rice are similar to those of lowland varieties.

Burkitt leukemia with numb chin syndrome and cavernous sinus involvement.

Cavernous sinus syndrome is a rare event. Non-Hodgkin lymphomas, are one possible cause. Neurological presentation of these lymphomas is also exceptional. We report the case of an 11-year-old boy that developed a right third cranial nerve palsy and numbness in the distribution of the right mental nerve, with normal CSF, and enlargement of cavernous sinus on the same side, who was diagnosed Burkitt leukemia.

Resting-State Functional Magnetic Resonance Imaging for Language Preoperative Planning.

Functional magnetic resonance imaging (fMRI) is a well-known non-invasive technique for the study of brain function. One of its most common clinical applications is preoperative language mapping, essential for the preservation of function in neurosurgical patients. Typically, fMRI is used to track task-related activity, but poor task performance and movement artifacts can be critical limitations in clinical settings. Recent advances in resting-state protocols open new possibilities for pre-surgical mapping of language potentially overcoming these limitations. To test the feasibility of using resting-state fMRI instead of conventional active task-based protocols, we compared results from fifteen patients with brain lesions while performing a verb-to-noun generation task and while at rest. Task-activity was measured using a general linear model analysis and independent component analysis (ICA). Resting-state networks were extracted using ICA and further classified in two ways: manually by an expert and by using an automated template matching procedure. The results revealed that the automated classification procedure correctly identified language networks as compared to the expert manual classification. We found a good overlay between task-related activity and resting-state language maps, particularly within the language regions of interest. Furthermore, resting-state language maps were as sensitive as task-related maps, and had higher specificity. Our findings suggest that resting-state protocols may be suitable to map language networks in a quick and clinically efficient way.

Brain magnetic resonance imaging: perception and expectations of neurologists, neurosurgeons and psychiatrists.

Magnetic resonance imaging (MRI) has rapidly become an essential diagnostic tool in modern medicine. Understanding the objectives, perception and expectations of the different medical specialties towards MRI is therefore important to improve the quality of the examinations. Our aim was to better comprehend the reasons and expectations of neurologists, neurosurgeons and psychiatrists when requesting brain MRI scans for their patients, and also to perceive the degree of confidence of these specialists in the images and respective reports. Sixty-three specialists were recruited from two tertiary hospitals and answered a tailored questionnaire. Neurosurgeons were more concerned with the images themselves; neurologists lacked confidence in both MRI images and reports, and one third of the psychiatrists only read the report and were the most confident of the specialties in MRI findings. These results possibly reflect the idiosyncrasies of each of these medical specialties. This knowledge, driven by efficient communication between neuroradiologists and neurosurgeons, neurologists and psychiatrists, may contribute to improve the quality of MRI examinations and consequently patient care and management of health resources.

Temporal intradiploic dilative vasculopathy: an additional pathogenic factor for the hearing loss in fabry disease?

Fabry disease (FD) is caused by progressive accumulation of neutral glycosphingolipids, including in ganglion neural and vascular endothelial cells, as a result of lysosomal α-galactosidase deficiency. High frequencies progressive sensorineural hearing loss (HL), sudden deafness, tinnitus and dizziness are otological symptoms frequently reported.A 45-year-old man with FD, on haemodialysis since age 25, complaining of progressive HL, was started on enzyme replacement therapy (ERT) because of cardiac complications. A bilateral sloping sensorineural HL was found at baseline audiological evaluation. Computed tomography of the ears showed enlargement of the intradiploic vascular channels, principally in the petrous bone. The magnetic resonance angiography showed elongation and ectasia of the middle cerebral arteries and the arteries of the Circle of Willis, particularly the internal carotid and the basilar arteries. Follow-up audiological evaluations documented progressive worsening of HL, mainly in the high frequencies range, despite high dose ERT and evidence of cardiac improvement.The intradiploic vascular abnormalities of the temporal bones reported herein have never been described in association with FD and may have contributed to the pathogenesis of progressive HL, by a 'stealing' effect upon the cochlear blood supply (like in cavernous haemangioma of the internal auditory meatus), in addition to the other mechanisms of ischaemic injury to the Organ of Corti described in FD. This clinical observation shows the value of comprehensive neuroimaging investigation of HL in FD and emphasizes the importance of early institution of specific therapy, before the occurrence of irreversible inner ear lesions and hearing damage.

Giant left middle fossa VII nerve schwannoma associated with amnesia.

The facial nerve is the third most frequent location of intracranial schwannomas, with facial paresis the most common sign.(1,2) A 77-year-old woman presented with amnesia; the Mini-Mental State Examination score was 26, with normal cranial nerve function. A giant multicystic VII nerve schwannoma was identified in the left middle fossa, with components of the tumor in the temporal bone facial canal, geniculate ganglion, and internal auditory canal (figure). Compression of the hippocampus may have accounted for the clinical presentation. The middle fossa component of the tumor was resected for mass effect relief, with iatrogenic facial palsy.

Oxygen desaturation in healthy subjects undergoing the incremental shuttle walk test.

OBJECTIVE: To determine the probability of oxygen desaturation in healthy individuals undergoing the incremental shuttle walk test (ISWT). METHODS: We enrolled 83 healthy subjects: 55 males (including 1 smoker) and 28 females. We determined pre-ISWT FEV1, FEV6, HR and SpO2, as well as post-ISWT HR and SpO2. RESULTS: Mean values overall were as follows: age, 35.05 ± 12.53 years; body mass index, 24.30 ± 3.47 kg/m2; resting HR, 75.12 ± 12.48 bpm; resting SpO2, 97.96 ± 1.02%; FEV1, 3.75 ± 0.81 L; FEV6, 4.45 ± 0.87 L; FEV1/FEV6 ratio, 0.83 ± 0.08 (no restriction or obstruction); incremental shuttle walk distance, 958.30 ± 146.32 m; post-ISWT HR, 162.41 ± 18.24 bpm; and post-ISWT SpO2, 96.27 ± 2.21%. In 11 subjects, post-ISWT SpO2 was higher than was pre-ISWT SpO2. In 17 subjects, there was a 4% decrease in SpO2 after the ISWT. There were no statistically significant differences between the groups with and without post-ISWT oxygen desaturation in terms of age, gender, FEV1, FEV6, FEV1/FEV6, pre-ISWT SpO2, incremental shuttle walk distance, HR, or percentage of maximal HR. In the individuals with post-ISWT oxygen desaturation, the body mass index was higher (p = 0.01) and post-ISWT SpO2 was lower (p = 0.0001). CONCLUSIONS: Healthy individuals can present oxygen desaturation after the ISWT. Using the ISWT to predict subtle respiratory abnormalities can be misleading. In healthy subjects, oxygen desaturation is common after the ISWT, as it is during any intense physical activity.

Investigating the role of the ventromedial prefrontal cortex in the assessment of brands.

The ventromedial prefrontal cortex (vmPFC) is believed to be important in everyday preference judgments, processing emotions during decision-making. However, there is still controversy in the literature regarding the participation of the vmPFC. To further elucidate the contribution of the vmPFC in brand preference, we designed a functional magnetic resonance imaging (fMRI) study where 18 subjects assessed positive, indifferent, and fictitious brands. Also, both the period during and after the decision process were analyzed, hoping to unravel temporally the role of the vmPFC, using modeled and model-free fMRI analysis. Considering together the period before and after decision-making, there was activation of the vmPFC when comparing positive with indifferent or fictitious brands. However, when the decision-making period was separated from the moment after the response, and especially for positive brands, the vmPFC was more active after the choice than during the decision process itself, challenging some of the existing literature. The results of the present study support the notion that the vmPFC may be unimportant in the decision stage of brand preference, questioning theories that postulate that the vmPFC is in the origin of such a choice. Further studies are needed to investigate in detail why the vmPFC seems to be involved in brand preference only after the decision process.

Pain in portuguese patients with multiple sclerosis.

Early reports often ignored pain as an important symptom in multiple sclerosis (MS). Pain prevalence figures in MS from European countries other than Portugal range between 40 and 65%. To our knowledge there is no published data in English on pain in MS in Portugal. We describe the demographic and clinical characteristics, with an emphasis on pain, of 85 MS patients followed-up in a Portuguese hospital, contributing to pain epidemiology in MS. Patients were interviewed sequentially after their regular appointments at the MS clinic; patients with pain completed The Brief Pain Inventory and The McGill Pain Questionnaire (MPQ). The prevalence of pain found was 34%. Headache and back pain were the most common anatomical sites described, followed by upper and lower limbs. Intensity of pain in an 11-point scale was, for the maximum pain intensity 6.7 ± 1.8, for the minimum pain intensity 2.2 ± 2.0, for the mean pain intensity 4.5 ± 1.5, and for the actual pain intensity 2.4 ± 2.9. Pain interfered significantly with general activity, mood, work, social relations, and enjoyment of life. All MS patients with pain employed words from both the sensory and affective categories of the MPQ to describe it. Patient pain descriptions' included the word "hot-burning" in 59% of the cases, common in the report of central pain, but neuropathic pain medications were only used by 10% of them. Pain is an important symptom in Portuguese patients with MS, not only because of the high prevalence found, concordant with other European countries, but also because of its interference with quality-of-life.

[Pain in multiple sclerosis: characterization of a Portuguese population of 85 patients]. / Dor na esclerose múltipla: caracterização de uma população Portuguesa de 85 doentes.

Multiple sclerosis (MS) is a frequent neurological disease, with an estimated prevalence in Portugal of 60/100.000. It is a disease of the young adult, whose first symptoms are commonly of sensory type. The pathological process is of inflammatory nature, involving the central nervous system. The typical histopathological lesion is an area of demyelination. Initial descriptive studies affirmed that pain was an uncommon symptom in MS. However, it soon became evident that the majority of MS patients experience pain in the course of their disease. In MS it is possible to find any kind of pain syndrome, being the most common central neuropathic pain. A sample of 85 MS patients of the Outpatient Clinic of Demyelinating Diseases of the Neurology Department of São João Hospital, Oporto, Portugal, was studied. The presence of pain, demographic characteristics, disease duration, year of diagnosis, MS subtype, treatments and Expanded Disability Status Scale (EDSS) score were investigated. The group of MS patients with pain completed the short versions of the pain questionnaires The Brief Pain Inventory (BPI) and The McGill Pain Questionnaire (MPQ), for more detailed pain characterization. The prevalence of pain found was 34%. We have not established an association between the existence of pain and disease duration or functional impairment. However, pain interfered significantly with the patients' general activity, mood, work, social relations with others and enjoyment of life. All the pain and MS patients that completed the MPQ employed more than one word to describe their pain, using always words from both the sensory and affective categories. Patient pain descriptions included the word hot-burning in 58,8% of the cases; this word is used commonly in the description of central neuropathic pain. Pain is an important symptom in 85 Portuguese patients with MS, not only because of the high pain prevalence found, but also because of its interference with their quality of life. Pain recognition in MS patients is fundamental to adequately treating MS patients with pain.

Oxygen desaturation in healthy subjects undergoing the incremental shuttle walk test / Dessaturação em indivíduos saudáveis submetidos ao incremental shuttle walk test

OBJECTIVE: To determine the probability of oxygen desaturation in healthy individuals undergoing the incremental shuttle walk test (ISWT). METHODS: We enrolled 83 healthy subjects: 55 males (including 1 smoker) and 28 females. We determined pre-ISWT FEV1, FEV6, HR and SpO2, as well as post-ISWT HR and SpO2. RESULTS: Mean values overall were as follows: age, 35.05 ± 12.53 years; body mass index, 24.30 ± 3.47 kg/m2; resting HR, 75.12 ± 12.48 bpm; resting SpO2, 97.96 ± 1.02%; FEV1, 3.75 ± 0.81 L; FEV6, 4.45 ± 0.87 L; FEV1/FEV6 ratio, 0.83 ± 0.08 (no restriction or obstruction); incremental shuttle walk distance, 958.30 ± 146.32 m; post-ISWT HR, 162.41 ± 18.24 bpm; and post-ISWT SpO2, 96.27 ± 2.21%. In 11 subjects, post-ISWT SpO2 was higher than was pre-ISWT SpO2. In 17 subjects, there was a 4% decrease in SpO2 after the ISWT. There were no statistically significant differences between the groups with and without post-ISWT oxygen desaturation in terms of age, gender, FEV1, FEV6, FEV1/FEV6, pre-ISWT SpO2, incremental shuttle walk distance, HR, or percentage of maximal HR. In the individuals with post-ISWT oxygen desaturation, the body mass index was higher (p = 0.01) and post-ISWT SpO2 was lower (p = 0.0001). CONCLUSIONS: Healthy individuals can present oxygen desaturation after the ISWT. Using the ISWT to predict subtle respiratory abnormalities can be misleading. In healthy subjects, oxygen desaturation is common after the ISWT, as it is during any intense physical activity. .

OBJETIVO: Determinar a probabilidade de dessaturação arterial em indivíduos saudáveis submetidos ao incremental shuttle walk test (ISWT). MÉTODOS: Foram estudados 83 indivíduos saudáveis, dos quais 55 eram homens (1 deles fumante) e 28 eram mulheres. Foram determinados VEF1 e VEF6 antes da realização do ISWT, assim como FC e SpO2 antes e depois do ISWT. RESULTADOS: As médias gerais foram as seguintes: idade, 35,05 ± 12,53 anos; índice de massa corporal, 24,30 ± 3,47 kg/m2; FC em repouso, 75,12 ± 12,48 bpm; SpO2 em repouso, 97,96 ± 1,02%; VEF1, 3,75 ± 0,81 L; VEF6, 4,45 ± 0,87 L; relação VEF1/VEF6, 0,83 ± 0,08 (sem restrição ou obstrução); distância percorrida no ISWT, 958,30 ± 146,32 m; FC pós-ISWT, 162,41 ± 18,24 bpm e SpO2 pós-ISWT, 96,27 ± 2,21% Em 11 indivíduos, houve um aumento da SpO2 após o ISWT, ao passo que em 17 houve uma queda de 4%. Não houve diferença estatística entre os grupos com e sem dessaturação após o ISWT no tocante às variáveis idade, gênero, VEF1, VEF6, VEF1/VEF6, SpO2 basal, distância percorrida no ISWT, FC e porcentagem da FC máxima. Nos indivíduos que apresentaram dessaturação, o índice de massa corporal foi maior (p = 0,01) e a SpO2 pós-ISWT foi menor (p = 0,0001). CONCLUSÕES: Indivíduos saudáveis podem apresentar dessaturação após o ISWT. O uso do ISWT para prever a presença de problemas respiratórios sutis pode ser enganador. Em indivíduos saudáveis, a dessaturação é um evento comum após o ISWT, assim ...