Primary headache subtypes and thyroid dysfunction: Is there any association? / Subtipos de cefaleia primária e disfunção tireoidiana: existe alguma associação?

ABSTRACT Background: Primary headaches, and particularly migraine and tension-type headache (TTH) as well as hypothyroidism are common medical conditions. To date, numerous studies have suggested a possible bidirectional relationship between migraine and hypothyroidism, although certain studies had contradictory results. Objective: To investigate whether there is any association between primary headache subtypes and thyroid disorders. Methods: A retrospective study of consecutive patients aged ≥18 years referred to the Headache Outpatient Clinic of Aeginition Hospital and diagnosed with primary headache and any thyroid disorder. Results: Out of 427 patients (males/females=76/351), 253 (59.3%) were diagnosed with migraine without aura, 53 (12.4%) with TTH, 49 (11.5%) with migraine with aura, 29 (6.8%) with medication-overuse headache, 23 (5.4%) with mixed-type headache (migraine with/without aura and TTH), nine (2.1%) with cluster headache, and 11 (2.6%) with other types of primary headaches. The prevalence of any type of thyroid disorder was 20.8% (89/427 patients). In the total sample, 27 patients (6.3%) reported hypothyroidism, 18 (4.2%) unspecified thyroidopathy, 14 (3.3%) thyroid nodules, 12 (2.8%) Hashimoto thyroiditis, 12 (2.8%) thyroidectomy, three (0.7%) thyroid goiter, and three (0.7%) hyperthyroidism. Further statistical analysis between categorical variables did not reveal any significant association between headache subtypes and thyroid dysfunction. Conclusions: No specific association was found between primary headache subtypes and specific thyroid disorder. However, a high prevalence of thyroid dysfunction in general and specifically hypothyroidism was demonstrated among patients with primary headaches, which lays the foundation for further clarification in prospective longitudinal studies.

RESUMO Introdução: Cefaleias primárias e, particularmente, enxaqueca e cefaleia do tipo tensional (CTT), bem como hipotiroidismo, constituem condições médicas comuns. Até o momento, vários estudos sugeriram uma possível relação bidirecional entre enxaqueca e hipotireoidismo, embora alguns estudos tenham resultados contraditórios. Objetivo: Investigar se existe associação entre subtipos de cefaleia primária e distúrbios da tireoide. Métodos: Estudo retrospectivo de pacientes consecutivos com idade ≥18 anos encaminhados ao Ambulatório de Cefaleia do Hospital Aeginition, com diagnóstico de cefaleia primária e qualquer distúrbio da tireoide. Resultados: De 427 pacientes (homens/mulheres=76/351), 253 pacientes (59,3%) foram diagnosticados com enxaqueca sem aura, 53 (12,4%) com CTT, 49 (11,5%) com enxaqueca com aura, 29 (6,8 %) com cefaleia por uso excessivo de medicamentos, 23 (5,4%) com cefaleia mista (enxaqueca com/sem aura e CTT), nove (2,1%) com cefaleia em salvas e 11 (2,6%) com outros tipos de cefaleias primárias. A prevalência de qualquer tipo de distúrbio tireoidiano foi de 20,8% (89/427 pacientes). Na amostra total, 27 pacientes (6,3%) relataram hipotireoidismo, 18 (4,2%) tireoidopatia não especificada, 14 (3,3%) nódulos de tireoide, 12 (2,8%) tireoidite de Hashimoto, 12 (2,8%) tireoidectomia, três (0,7%) bócio da tireoide e três (0,7%) hipertireoidismo. Uma análise estatística posterior entre as variáveis categóricas não revelou qualquer associação significativa entre os subtipos de cefaleia e disfunção tireoidiana. Conclusões: Não encontramos associação entre subtipos de cefaleia primária e distúrbio específico da tireoide. No entanto, foi observada prevalência elevada de disfunção tireoidiana em geral e especificamente hipotireoidismo entre pacientes com cefaleia primária, o que estabelece base para maiores esclarecimentos em estudos longitudinais prospectivos.

Prevalência de cefaleia em adolescentes e associação com uso de computador e jogos eletrônicos / Prevalence of headache in adolescents and association with use of computer and videogames

Este estudo objetivou verificar a prevalência de cefaleia em adolescentes e sua associação com o uso excessivo de computador e jogos eletrônicos. A amostra foi composta por 954 adolescentes (14 a 19 anos), de ambos os sexos, que responderam ao questionário sobre uso de computadores e jogos eletrônicos, presença de cefaleia e atividade física. Foi utilizada a regressão logística binária e multinomial, com nível de significância de 5%. Evidenciou-se alta prevalência de cefaleia (80,6%) e elevado tempo de uso de dispositivos eletrônicos. O uso excessivo dos dispositivos eletrônicos mostrou-se fator de risco para cefaleia. Os sujeitos com idade entre 14 e 16 anos apresentaram menor chance de relatar a cefaleia. Em relação ao tipo, 17,9% apresentaram cefaleia do tipo tensional, 19,3% migrânea e 43,4% outros tipos de cefaleia. Os adolescentes com idade entre 14 e 16 anos apresentam menor chance de relatar a cefaleia do tipo tensional e de outros. Estar cursando o terceiro ano e usar excessivamente equipamentos digitais mostraram-se fatores de risco para cefaleia migrânea. Os resultados permitem concluir que o uso excessivo de dispositivos eletrônicos está associado à presença de cefaleia, principalmente do tipo migrânea.

The aim of this study was to determine the prevalence of headache in adolescents and its association with excessive use of electronic devices and games. The sample comprised 954 adolescents of both sexes (14 to 19 years) who answered a questionnaire about use of computers and electronic games, presence of headache and physical activity. The binary and multinomial logistic regression, with significance level of 5% was used for inferential analysis. The prevalence of headache was 80.6%. The excessive use of electronics devices proved to be a risk factor (OR = 1.21) for headache. Subjects aged between 14 and 16 years were less likely to report headache (OR = 0.64). Regarding classification, 17.9% of adolescents had tension-type headache, 19.3% had migraine and 43.4% other types of headache. The adolescents aged form 14 to 16 years had lower chance (OR ≤ 0.68) to report the tension-type headache and other types of headache. The excessive use of digital equipment, electronic games and attending the third year of high school proved to be risk factors for migraine-type development (OR ≥ 1.84). There was a high prevalence of headache in adolescents and high-time use of electronic devices. We observed an association between excessive use of electronic devices and the presence of headache, and this habit is considered a risk factor, especially for the development of migraine-type.

Asimetrías faciales como factor etiopatogénico de cefaleas y dolor facial / Facial asymmetries as etiopathogenic factors of headache and facial pain

El objetivo de este estudio fue demostrar la hipótesis sobre la coexistencia de asimetría morfológica con actividad muscular asimétrica, y deesta última con disfunción cráneomandibular y cefalea tensional y dolor facial, para incorporar datos semiológicos al diagnóstico tempranoy tratamiento precoz de las disfunciones cráneo-cérvico mandibulares. Participaron del estudio 66 alumnos de la F.O.U.B.A. con signos y/o síntomas de disfunción cráneomandibular. El diagnóstico de dolor se realizó mediante cuestionarios siguiendo los criterios diagnósticos de la Internacional Headache Society. La determinación de asimetría se realizó midiendo segmentos y ángulos trazados en telerradiografíade frente para tejidos duros y fotografía de cara de frente para tejidos blandos. Se evaluó la función muscular mediante electromiografía de superficie (EMGS); y la dinámica del sistema estomatognático mediante el método magnetométrico. El análisis de regresión logística múltiple resultó significativo al nivel p=0.01. En el análisis de las variables individuales y el dolor se encontró correlación estadísticamente significativa entre la asimetría de tejidos duros y la presencia de cefalea tensional y/o dolor facial. El organismo intenta equilibrar las diferencias morfológicas, esto explicaría las asimetrías cruzadas entre tejidos duros, blandos y actividad muscular comocompensaciones funcionales. Concluimos diciendo que ante la presencia de cefalea tensional y/o dolor facial debemos considerar la asimetríafacial de tejidos duros como posible factor etiológico predisponente aunque no se observe asimetría en tejidos blandos por acción compensatoria de la dinámica muscular. La etiología mixta, oclusal y postural, de las asimetrías faciales requiere del trabajo interdisciplinario odontólogo-médico-kinesiólogo-psicólogo-fonoaudiólogo para un óptimo diagnóstico y tratamiento

The aim of this study was to test the hypothesis on the coexistence of morphological asymmetry with asymmetric muscle activity, and this one with craniomandibular dysfunction and tension headache and facial pain, to incorporate semiological data to early diagnosis and treatment for TMJD (temporo mandibular jaw dysfunction). Study participants were 66 students from the Faculty of Dentistry of the University of Buenos Aires with TMJD signs and / or symptoms. The diagnosis of pain was conducted by questionnaires following the diagnostic criteria of the International Headache Society. The asymmetry determination was performed by measuring segments and angles in cephalometric frontal tracings for hard tissues and frontal picture for soft tissues. Muscle function was evaluated by surface electromyography (SEMG) and stomatognathic system dynamics by magnetometric method. The multiple logistic regression analysis was significant at p = 0.01. In the analysis of individual variables and pain we found statistical correlation between the asymmetry of hard tissues and the presence of tension headache and / or facial pain. The body tries to balance the morphological differences; this would explain the asymmetries cross between hard tissues, soft and functional muscle activity as offsets. We conclude saying that in the presence of tension headache and/or facial pain, the hard tissue facial asymmetry should be considered as a possible etiologic factor predisposing even asymmetry is not observed in soft tissue because of compensatory action of muscle dynamics. The mixed etiology, occlusal and postural of the facial asymmetries, requires interdisciplinary work dentist-doctor-physiotherapist,-psychologist-speech therapist, for optimal diagnosis and treatment.

Frequência dos tipos de cefaleia no centro de atendimento terciário do Hospital das Clínicas da Universidade Federal de Minas Gerais / Frequency of types of headache in the tertiary care center of the Hospital das Clínicas of the Universidade Federal de Minas Gerais, MG, Brazil

OBJETIVO: Avaliar a frequência dos diferentes diagnósticos de cefaleias do Ambulatório de Cefaleias do Hospital das Clínicas da Universidade Federal de Minas Gerais (AmbCef-UFMG). MÉTODOS: Estudo transversal e descritivo com 289 pacientes atendidos consecutivamente no AmbCef-UFMG. O diagnóstico da cefaleia baseou-se nos critérios da Classificação Internacional das Cefaleias (ICDH-2004). RESULTADOS: A idade média dos pacientes foi 42,6 anos, sendo a maioria do sexo feminino (86,9%) e com menos de nove anos de escolaridade. As cefaleias primárias foram as mais comuns, sendo a migrânea encontrada em 79,8% dos casos e a cefaleia do tipo tensional (CTT), em 20,4%. Entre as secundárias, o tipo mais comum foi a cefaleia por uso excessivo de analgésicos (16,6%), seguido de casos menos comuns como a hipertensão intracraniana idiopática. A cefaleia crônica diária (CCD) esteve presente em 31,8% dos casos. CONCLUSÃO: Este estudo confirma dados da literatura que mostram a migrânea como a cefaleia mais comum em centros terciários. O número expressivo de casos de CCD e de uso excessivo de analgésicos indica que, desde o nível primário de atenção, os pacientes deveriam ser orientados a evitar o uso abusivo de medicação sintomática.

OBJECTIVE: To assess the frequency of different diagnoses of headaches in the Headache Outpatient Clinic of the Hospital das Clínicas of the Universidade Federal de Minas Gerais (AmbCef-UFMG). METHODS: Cross sectional study with 289 patients consecutively attended to at AmbCef-UFMG. Headaches were diagnosed based on the criteria established by the International Classification of Headache Disorders (ICDH-2004). RESULTS: The average age of patients was 42.6 years, mostly women (86.9%) with less than nine years of education. Primary headaches were the most common type, with migraine found in 79.8% of cases, and tension-type headache (TTH) in 20.4%. Among the secondary types, the most common was headache caused by overuse of analgesics (16.6%), followed by less common types, such as idiopathic intracranial hypertension. Chronic daily headache (CDH) was found in 31.8% of cases. CONCLUSION: This study confirms literature data showing migraine as the most common headache in tertiary care centers. The expressive number of cases of CDH and headaches caused by overuse of analgesics indicates that, starting at the primary care level, patients should be advised to avoid the abuse of symptomatic drugs.

Headache among medical and psychology students / Cefaléia em estudantes de medicina e psicologia

Headaches occur frequently and thus are a key component of sociocentric medical education. OBJECTIVE: To study headaches among students of medicine and psychology in a single university. METHOD: This was a questionnaire-based survey of a cohort of students of medicine and psychology. RESULTS: The overall lifetime prevalence of headache was 98 percent and over the last year, 91 percent. Tensional headache accounted for 59 percent and migraine 22 percent in medicine; and 48.5 percent and 32 percent respectively in psychology. Forty-five percent reported that headaches had a variable sporadic impact on their productivity. The self-medication rate was 77 percent. Thirty-six percent reported worsening since admission to the university. CONCLUSION: The prevalence of headaches was very high. Tension-type headaches predominated in males and migraine in females. Tension-type was more frequent among medical students than among psychology students; migraine was more frequent in psychology (more females) than in medicine. Both kinds of students reported that headaches caused low interference with daily activities. The students reported that their symptoms had worsened since admission to the university.

Cefaléia é frequente e tema importante para a educação médica sociocêntrica. OBJETIVO: Estudar cefaléias entre estudantes de medicina e de psicologia. MÉTODO: Foi estudo coorte, baseado num questionário respondido pelos estudantes. RESULTADOS: Cefaléia pelo menos uma vez na vida ocorreu em 98 por cento dos estudantes; no último ano, 91 por cento.Cefaléia tensional ocorreu em 59 por cento e enxaqueca em 22 por cento na Medicina; na Psicologia 48,5 por cento e 32 por cento, respectivamente. De todos os estudantes, 45 por cento relataram interferência variável na produtividade. No geral, a taxa de automedicação foi 77 por cento; relataram piora da cefaléia desde o ingresso na universidade 36 por cento. CONCLUSÃO: A prevalência de cefaléias foi muito alta. Cefaléia tensional predominou nos homens e enxaqueca nas mulheres. Cefaléia tensional ocorreu mais na Medicina do que na Psicologia; enxaqueca foi mais prevalente em Psicologia (onde havia predomínio do gênero feminino) do que Medicina. Nos dois grupos houve baixa interferência na produtividade; houve piora dos sintomas desde o ingresso na universidade.

Frequency of headache among the employees of a rubber company in the state of São Paulo, Brazil / Frequência de cefaleia em trabalhadores de uma empresa de borracha no Estado de São Paulo, Brasil

CONTEXT AND OBJECTIVE: Primary headaches may be responsible for absenteeism and a fall in the yield and productivity of work. The aim of this study was to establish the presence and frequency of primary headache among employees of a rubber shoe sole company, and its link to absenteism. DESIGN AND SETTING: Cross-sectional study carried out with help from the staff of the medical and social department of a rubber factory located in the municipality of Franca, São Paulo. METHOD: A questionnaire on headache characteristics was distributed to all employees. The returned and completed questionnaires were divided into two groups: with and without reports of headache. The headaches were classified into four main groups: migraine, tension-type headache (TTH), cluster headache and others. In terms of the reported frequency, headaches were also classified as chronic daily headache (CDH). RESULTS: The number of valid questionnaires was 392 (59 percent); 80.9 percent were from male and 19.1 percent from female employees. Headaches were reported by 120 subjects (30.6 percent), with 17.4 percent belonging to the migraine group and 8.9 percent to the TTH group. Migraine was more frequent (p < 0.001) among all participants and also among the women (p < 0.05). TTH was more frequent among the men (p < 0.05). CDH was identified in 14 individuals (3.6 percent). CONCLUSIONS: Headache was a common problem among the employees of this company and was a cause of absenteeism for 8.7 percent of the respondents to the questionnaire.

CONTEXTO E OBJETIVO: Cefaleias primárias podem ser causa de absenteísmo, e de queda no rendimento e na produtividade do trabalho. O objetivo do estudo foi estabelecer a presença e frequência de cefaleia primária em funcionários de uma empresa de solados de borracha,e sua relação com absenteísmo. TIPO DE ESTUDO E LOCAL: Estudo transversal realizado com a ajuda do pessoal do departamento médico e social de uma empresa localizada no município de Franca, São Paulo. MÉTODO: Um questionário sobre as características da cefaleia foi distribuído a todos os funcionários. Os questionários devolvidos e preenchidos foram divididos em dois grupos: com e sem relato de cefaleia. As cefaleias foram classificadas em quatro grupos principais: migrânea, cefaleia do tipo tensional (CTT), cefaleia em salvas e outras cefaleias. Através da frequência da cefaleia, foi possível a classificação em cefaleia crônica diária (CCD). RESULTADOS: O número de questionários válidos foi de 392 (59 por cento), 80,9 por cento questionários eram de funcionários do gênero masculino, e 19,1 por cento, do gênero feminino. Cento e vinte (30,6 por cento) dos funcionários relataram apresentar cefaleia, sendo que 17,4 por cento pertenceram ao grupo migrânea e 8,93 por cento ao grupo CTT. O diagnóstico de migrânea foi o mais frequente (p < 0,001) dentre todos, e também entre as mulheres (p < 0,05). O diagnóstico de CTT foi mais frequente entre os homens (p < 0,05). CCD foi identificada em 14 indivíduos (3,6 por cento). CONCLUSÕES: Cefaleia é um problema frequente entre os funcionários da empresa participante da pesquisa sendo a causa de absentismo em 8,7 por cento dos que responderam o questionário.

Recurrent headache in indian adolescents.

Objective. To analyze the epidemiology and characteristics of primary recurrent headaches in Indian adolescents. Methods. This cross sectional study was conducted in three urban public schools. Adolescents of 9th to 12th grades were included and they were given a questionnaire in their classrooms in the presence of at least one of the authors, who assisted them in filling it. They were asked to provide responses based on most severe recurrent headache they had experienced rather than the more frequent one. Diagnosis was based upon the information contained in questionnaire, however, where it was inadequate, those subjects were approached telephonically. Statistical analysis was done with the help of SPSS v. 11.0. Descriptive analysis, Chi-Square test, Fisher’s Exact test, and independent sample‘t’ test were run. Results. We studied 2235 adolescents (boys: girls 1.6:1). 57.5% adolescents reported recurrent headaches in past one year. Migraine was the most prevalent (17.2%) headache followed by unspecified (14.9%) and tension type headache (11%). Family history of headache was more common in adolescents with headache (p < 0.001) compared to those without headache. Average age of headache onset was 11.33 yr (10.72 yr in girls vs. 11.75 years in boys; p < 0.001). 37.1% adolescents complained of progression of headache since its onset. A significantly higher proportion of girls suffered headache (p=0.018), particularly migraine, than boys. However, other characteristics of headache were not dependent upon gender. Headache was more prevalent in higher grades. Conclusion. Primary recurrent headaches are prevalent in Indian adolescents and migraine is comparatively the most prevalent type of headache. Female gender and increasing age is associated with higher chances to have headache, particularly migraine. It progresses in approximately one third of sufferers and aura increases the chances of worsening of headache.

Chronic daily headache: medications overuse and psychiatric morbidity

The objectives of the study were: [i] To assess the frequency of different chronic daily headaches in patients using ICHD-2 criteria [ii] To find out the frequency and type of medication overuse and psychiatric morbidity in chronic daily headache subjects. Cross sectional observational study. The study was conducted in the psychiatry outpatient department of a teaching medical institution during January to September 2005. Subjects suffering from chronic daily headache were recruited from a specialized headache clinic in a tertiary care hospital's Psychiatry department. The diagnoses were made according to ICHD-2. Medication overuse was defined according to ICHD-2 criteria and psychiatric illness was diagnosed following ICD-10 criteria in CDH patients. In subjects fulfilling the criteria for 'medication overuse', the culprit drug was stopped immediately and prophylactic therapy was started. Frequency of chronic daily headache was 37% in this sample. Females outnumbered males [1:1.52] and formed higher number of migraine cases [p=0.02]. Tension Type Headache [TTH] was most frequent headache [48.5%]. According to ICHD-2 criteria, probable medication overuse headache could be diagnosed in all patients, which precluded the diagnosis of chronic migraine and chronic TTH. Psychiatric morbidity was seen in 70.3% subjects and mild to moderate depression was the most common illness [53%]. TTH subjects showed predisposition for anxiety disorders [OR= 6.41; p= 0.004]. TTH is the most common subtype of CDH when ICHD-2 is followed. Medication overuse is common in this group of patients and these probably should be discontinued according to substance dependence de-addiction model for better compliance, and even more slowly in subjects with chronic migraine headache. Psychiatric morbidity is prevalent in CDH patients and requires special attention

Epidemiology of primary and secondary headaches in a Brazilian tertiary-care center

OBJETIVO: Analisar os aspectos demográficos da população em estudo, o tempo decorrido desde o início da queixa de cefaléia até a busca pelo serviço, assim como o diagnóstico das cefaléias primárias e secundárias. MÉTODO: 3328 pacientes foram analisados retrospectivamente de acordo com sexo, idade, raça, escolaridade, tempo decorrido entre o início da cefaléia e a busca ao médico e diagnóstico (ICHD-II, 2004). RESULTADOS: A razão Mulher/Homem foi 4:1, ambos com média de idade 40,7±15anos, não havendo diferença significativa entre os sexos. Aproximadamente 65% dos pacientes eram brancos e 55% tinha menos de 8 anos de escolaridade. A duração da queixa de cefaléia até a primeira consulta foi de 1 a 5 anos em 32,99% dos pacientes. Os diagnósticos mais prevalentes foram: migrânea (37,98%), cefaléia do tipo tensional-CTT (22,65%) e cefaléia em salvas (2,73%). CONCLUSÃO: Existem poucos dados epidemiológicos de pacientes atendidos em serviços terciários, principalmente em países subdesenvolvidos. De acordo com a literatura, a migrânea foi mais prevalente que a CTT. Também é relevante observar a baixa escolaridade da população, assim como o grande tempo de espera até a primeira consulta. Um número incomum de pacientes com síndrome de cefaléia hípnica foi observado na amostra.

Prevalence of migraine and tension-type headache in primary-school children in Shiraz

From January to June 2003 we determined the prevalence of the various types of headache in 2226 schoolchildren in Shiraz [age 6- 13 years] selected by multistage random sampling. Data were collected by questionnaire and clinical examination. International Headache Society criteria were used for diagnosis. The overall prevalence of headache was 31%. Prevalence rates of migraine and tension- type headache were 1.7% and 5.5% respectively. The prevalence of headache increased with age and girls were significantly more likely to report tensions-type headache. Positive family history of headache and abnormal sleep pattern were significantly associated with migraine

Prevalence of migraine and tension-type headache and their correlations in Shiraz primary school children [2003]

Studies of headache prevalence are numerous, and findings have varied according to the specific population and regions involved. No data are available regarding headache prevalence among Iranian children aged 6-13 years. The purpose of this study was to determine the prevalence rates of the various causes of headache in school children, with special emphasis on migraine, tension-type headache and their correlates in primary schools of Shiraz. A cross-sectional study was carried out on 2226 school children. Subjects were selected by multistage random sampling procedure. Data was collected by screening IHS questionnaire followed by clinical interviews, general physical and neurological examination, and diagnostic criteria of the international headache society. The overall prevalence rate of headache was estimated to be 31% [95% CI, 29-32.9]. Migraine and tension-type headache rates were estimated as 1.7% [95% CI, 1.2- 2.2] and 5.5% [95% CI, 4.6 - 6.4], respectively. The prevalence of headache types increases with age. There was no difference in prevalence of migraine between girls and boys [p>0.05] and prevalence of tension type headache was more in girls [p<0.05]. Positive family history of headache and abnormal sleep pattern showed significantly association with migraine. The prevalence of tension type headache in Iran compared to other countries is higher. So it is concluded that sleep disturbances and family history of headache had most significant effects on the occurrence of migraine and tension-type headache

Cefalea en el niño: utilidad de la clasificación internacional (IHS) 1988 / Headache in children: the utility of the international classification of headache (IHS) 1988

El objetivo de este estudio prospectivo de cefalea en el niño fue conocer la prevalencia de consultas por cefalea en el policlínico de Neurología del Hospital Roberto del Río, las características clínicas, el tipo de cefalea y la utilidad en niños de la clasificación internacional de cefalea dadapor la Internacional Headache Society 1988. Entre enero y junio 1994, tuvimos 114 consultas por cefalea, de un total de 5 612, al policlínico de Neurología del Hospital de Niños Roberto del Río, lo que dio una prevalencia de 2 por ciento. Hubo 68 mujeres y 46 hombres, edades entre 3,5 y 14,8 años. Todos sufrían cefaleas recurrentes. La aplicación de la clasificación internacional nos permitió clasificar el 75 por ciento de los casos, con una distribución de 66 por ciento vascular, 8 por ciento tensional y 26 por ciento no definida