ASA + Estatinas son solo costo-efectivas en alto riesgo cardiovascular

ASA + statins only cost-effective at high risk

Clinical Question:<!–
D([“mb”,”\u003c/h3\u003e\n\u003cp\u003e\n In men without a history of cardiovascular disease, is low-dose aspirin, a statin, or both drugs \ncost-effective in preventing cardiovascular events?\n\u003c/p\u003e\n\n\u003ch3\u003eBottom Line:\u003c/h3\u003e\n\u003cp\u003e\n From the viewpoint of cost to a third-party payer, the costs of aspirin alone are reasonable in \nmen at low-risk for coronary heart disease (CHD); the addition of a statin to aspirin therapy in \nthese men is above what is considered to be reasonable cost for prevention. However, the \ncombination of aspirin and a statin is cost-effective when men are at high risk (10% or above). \u003ca href\u003d\”http://www.infopoems.com/levels.html\” target\u003d\”_blank\” onclick\u003d\”return top.js.OpenExtLink(window,event,this)\”\u003e(LOE \u003d 2a)\u003c/a\u003e\n\u003c/p\u003e\n\n\u003ch3\u003eReference:\u003c/h3\u003e\n\u003cp\u003e\n \u003ca href\u003d\”http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd\u003dRetrieve\u0026amp;db\u003dPubMed\u0026amp;list_uids\u003d16520473\u0026amp;dopt\u003dAbstract\” target\u003d\”_blank\” onclick\u003d\”return top.js.OpenExtLink(window,event,this)\”\u003ePignone \nM, Earnshaw S, Tice JA, Pletcher MJ. Aspirin, statins, or both drugs for the primary prevention of \ncoronary heart disease events in men: A cost-utility analysis. Ann Intern Med 2006;144:326-36.\u003c/a\u003e\n\u003c/p\u003e\n\n\u003cdiv\u003e\n\u003ch3\u003eStudy Design:\u003c/h3\u003e\n\u003cp\u003e\n Cost-effectiveness analysis\n\u003c/p\u003e\n\u003c/div\u003e\n\n\n\u003cdiv\u003e\n\u003ch3\u003eFunding:\u003c/h3\u003e\n\u003cp\u003e\n Industry + govt\n\u003c/p\u003e\n\u003c/div\u003e\n\n\n\u003cdiv\u003e\n\u003ch3\u003eSetting:\u003c/h3\u003e\n\u003cp\u003e\n Outpatient (any)\n\u003c/p\u003e\n\u003c/div\u003e\n\n\n\u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eSynopsis:\u003c/h3\u003e\n\u003cp\u003e\n Although both aspirin and statin drugs, separately, are effective for preventing a first CHD \nevent, there is no direct evidence that the combination is more effective than either alone. The \nresearchers conducting this analysis determined the cost-effectiveness of the combination from the \nperspective of a third-party payer and we can use this analysis to understand the relative benefits \nof the 2 treatments. The researchers started with a base-case scenario of a 45-year-old man with a \n10-year risk of CHD of 7.5% treated with aspirin, statin therapy, both, or neither for 10 years. \nThe outcome was the development of a CHD event — stroke, myocardial infarction, or death — over \nthe 10 years. The Markov model used in this analysis also assumed that all patients would be \ntreated with both drugs after 10 years and then estimated their life-time cost-utility ratio. They \nalso considered the major risks of treatment, gastrointestinal bleeding, and myopathy-related \ndeath, derived from results of clinical trials. “,1]
);

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In men without a history of cardiovascular disease, is low-dose aspirin, a statin, or both drugs cost-effective in preventing cardiovascular events?

Bottom Line:

From the viewpoint of cost to a third-party payer, the costs of aspirin alone are reasonable in men at low-risk for coronary heart disease (CHD); the addition of a statin to aspirin therapy in these men is above what is considered to be reasonable cost for prevention. However, the combination of aspirin and a statin is cost-effective when men are at high risk (10% or above). (LOE = 2a)

Reference:

Pignone M, Earnshaw S, Tice JA, Pletcher MJ. Aspirin, statins, or both drugs for the primary prevention of coronary heart disease events in men: A cost-utility analysis. Ann Intern Med 2006;144:326-36.

Study Design:

Cost-effectiveness analysis

Funding:

Industry + govt

Setting:

Outpatient (any)

Synopsis:

Although both aspirin and statin drugs, separately, are effective for preventing a first CHD event, there is no direct evidence that the combination is more effective than either alone. The researchers conducting this analysis determined the cost-effectiveness of the combination from the perspective of a third-party payer and we can use this analysis to understand the relative benefits of the 2 treatments. The researchers started with a base-case scenario of a 45-year-old man with a 10-year risk of CHD of 7.5% treated with aspirin, statin therapy, both, or neither for 10 years. The outcome was the development of a CHD event — stroke, myocardial infarction, or death — over the 10 years. The Markov model used in this analysis also assumed that all patients would be treated with both drugs after 10 years and then estimated their life-time cost-utility ratio. They also considered the major risks of treatment, gastrointestinal bleeding, and myopathy-related death, derived from results of clinical trials. <!–
D([“mb”,”\u003cbr\u003e\n\u003cbr\u003e\nFor men at low risk, lifetime aspirin therapy increases their lifespan an average of 3 days \n(adjusted for quality of those days, or \u0026quot;quality-adjusted days\u0026quot;). Men at moderate (7.5%) risk \ngained an average 17 quality-adjusted days, and men at moderate to high risk (10%) gained 24 \nquality-adjusted days. When statin was theoretically added to aspirin treatment, the average \nincrease in lifespan was 13 days for low-risk men (an additional 10 days over aspirin alone), 35 \ndays for moderate risk (an additional 18 days), and 45 days (an additional 21 days) for men at \nmoderate to high risk. In men with low risk, the cost per quality-adjusted life-year is a very \nreasonable $9800 US for aspirin alone but $164,700 US for the combination. At moderate risk, \ncombination therapy is a reasonable $56,200 (though the range, depending on the sensitivity \nanalysis, was $26,100 to $246,276). At moderate to high risk the cost per quality-adjusted \nlife-year was $42,500 (range \u003d $20,600 – $188,000).\n\u003c/p\u003e\n\n\u003cp\u003e\n Copyright © 2006 by \u003ca href\u003d\”http://www.wiley.com/go/copyright\” target\u003d\”_blank\” onclick\u003d\”return top.js.OpenExtLink(window,event,this)\”\u003eWiley Subscription \nServices\u003c/a\u003e, Inc. All rights reserved.\n\u003c/p\u003e\n\n\n \u003c/div\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cdiv\u003e\n \u003cp\u003e\n \u003ca href\u003d\”http://www.infopoems.com\” target\u003d\”_blank\” onclick\u003d\”return top.js.OpenExtLink(window,event,this)\”\u003ewww.InfoPOEMs.com\u003c/a\u003e\n \u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003c/div\u003e\n \u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003e\n This is an automated email. Replies will be ignored.\u003cbr\u003e\n \u003ca href\u003d\”http://www.infopoems.com/support/dpOptions.cfm\” target\u003d\”_blank\” onclick\u003d\”return top.js.OpenExtLink(window,event,this)\”\u003eUnsubscribe or Manage your Daily InfoPOEMs delivery options\u003c/a\u003e from the InfoPOEMs Website.\n \u003cbr\u003e\n Copyright © 2006 by \u003ca href\u003d\”http://www.wiley.com/go/copyright\” target\u003d\”_blank\” onclick\u003d\”return top.js.OpenExtLink(window,event,this)\”\u003eWiley Subscription Services\u003c/a\u003e, Inc. All rights reserved. \u003ca href\u003d\”http://www.infopoems.com\” target\u003d\”_blank\” onclick\u003d\”return top.js.OpenExtLink(window,event,this)\”\u003e”,1]
);

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For men at low risk, lifetime aspirin therapy increases their lifespan an average of 3 days (adjusted for quality of those days, or “quality-adjusted days”). Men at moderate (7.5%) risk gained an average 17 quality-adjusted days, and men at moderate to high risk (10%) gained 24 quality-adjusted days. When statin was theoretically added to aspirin treatment, the average increase in lifespan was 13 days for low-risk men (an additional 10 days over aspirin alone), 35 days for moderate risk (an additional 18 days), and 45 days (an additional 21 days) for men at moderate to high risk. In men with low risk, the cost per quality-adjusted life-year is a very reasonable $9800 US for aspirin alone but $164,700 US for the combination. At moderate risk, combination therapy is a reasonable $56,200 (though the range, depending on the sensitivity analysis, was $26,100 to $246,276). At moderate to high risk the cost per quality-adjusted life-year was $42,500 (range = $20,600 – $188,000).

Antivirals slightly effective for influenza in healthy adults

Clinical Question: Are antivirals effective in preventing or treating healthy adults with influenza?

Bottom Line:

Antiviral agents are only slightly effective in preventing confirmed influenza or flu-like illness. When given in the first few days of illness, the M2 ion blockers and neuraminidase inhibitors reduce the duration of illness by approximately 1 day. (LOE = 1a)

Reference:

Jefferson T, Demicheli V, Rivetti D, Jones M, Di Pietrantonj C, Rivetti A. Antivirals for influenza in healthy adults: systematic review. Lancet 2006;367:303-13.

Study Design:

Systematic review

Funding:

Government

Setting:

Outpatient (any)

Synopsis:

These authors searched multiple databases for randomized controlled trials of antiviral medications in treating healthy adults aged 16 years to 65 years with influenza. Additionally, they sought unpublished studies. Two authors independently assessed which studies to include and assessed the quality of the included studies. A third member of the team refereed discrepancies. They analyzed 20 prophylaxis studies and 13 treatment trials using M2 ion blockers: amantidine (Symmetrel) and rimantidine (Flumadine). Additionally they analyzed 19 studies of the neuraminidase inhibitors zanamivir (Relenza) and oseltamivir (Tamiflu): prophylaxis, treatment, and postexposure prophylaxis. In the prophylaxis studies, amantidine prevented 61% of influenza A cases, but only 25% of flu-like illnesses. Adverse effects caused more patients to stop taking amantidine than placebo. Rimantidine was no better than placebo in preventing influenza and flu-like illness, and was also more likely to cause adverse effects that resulted in medication cessation. The neuraminidase inhibitors were no better than placebo in prophylaxis against flu-like illness. Oseltamivir prevents 54% of influenza cases and zanamivir 43%. In a single study, the neuraminidase inhibitors prevented lower respiratory tract infections in confirmed influenza cases but not in flu-like illnesses. The authors were unable to find any rigorous studies of oseltamivir on avian influenza. Unfortunately, the authors don’t provide enough detail to calculate numbers needed to treat or numbers needed to treat to harm.

Chlamydia Rapid Test as accurate as conventional testing

Clinical Question: Can a point-of-care test for Chlamydia trachomatis using vaginal swabs be used as an accurate screening test?

Bottom Line:

The Chlamydia Rapid Test, a point-of-care test that can be read in approximately 30 minutes, has a sensitivity of 83% and a specificity of 99%. Used in higher-risk areas as a screening test, it will rule out Chlamydia infection in 98% of women who don’t have it. It uses vaginal swab samples as an alternative to urine samples, which may be easier to collect. It is certified by the European Union (CE), but not yet available in the United States or Canada. (LOE = 1c)

Reference:

Mahilum-Tapay L, Laitila V, Wawrzyniak JJ, et al. New point of care Chlamydia Rapid Test — bridging the gap between diagnosis and treatment: performance evaluation study. BMJ 2007;335(7631):1190-1194.

Study Design:

Diagnostic test evaluation

Funding:

Foundation

Setting:

Outpatient (specialty)

Synopsis:

The researchers enrolled 1349 young women attending either a sexual health center or 1 of 2 genitourinary medicine clinics in the United Kingdom to evaluate the Chlamydia Rapid Test. The prevalence of disease ranged from 6% to 9.4% at the 3 sites. The gold standard was first-void urine sample testing by polymerase chain reaction assay and was conducted on all women. For the rapid test, women were given vaginal swabs for self-collection of a sample for analysis. The rapid test result can’t be seen until 25 minutes following preparation of the sample, but can then be read as a simple line on a test strip. The sensitivity of the rapid test was 82.7% and the specificity was 98.8%. The predictive values ranged from 80.6% to 93.8% (positive) and 98% to 99% (negative), depending on the prevalence at each site. A survey found that most (95.9%) women felt comfortable collecting their own vaginal swab specimens and 75% were willing to wait between 30 minutes and 2 hours for their test results.

PNB n-terminal reduz custos e taxas de re-hospitalização em pacientes dispnéicos

PNB n-terminal reduz custos e taxas de re-hospitalização em pacientes dispnéicos

Questão clínica
O uso do teste do peptídeo natriurético B melhora os resultados clínicos e econômicos de pacientes hospitalizados com dispnéia?

Resumo
O uso do peptídeo natriurético B (PNB) N-terminal reduz os custos de cuidados, a permanência no pronto-socorro (PS) e a probabilidade de re hospitalização quando usado na avaliação dos pacientes que se apresentam no PS com dispnéia. Entretanto, ele não reduz a mortalidade e nem a duração da estadia no hospital.

Nível de evidência: 1 b

Referência
Moe GW, Howlett J, Januzzi JL, Zowall H; Canadian Multicenter Improved Management of Patients With Congestive Heart Failure (IMPROVE-CHF) Study Investigators. N-terminal pro-B-type natriuretic peptide testing improves the management of patients with suspected acute heart failure: primary results of the Canadian Prospective Randomized Multicenter IMPROVE-CHF study. Circulation 2007;115(24):3103-3110.

Desenho de estudo: ensaio randomizado controlado (cego-simples)

Apoio financeiro: indústria

Distribuição da amostra: mascarada

Casuística: pacientes internados (quaisquer) com seguimento ambulatorial

Discussão
Às vezes, exames adicionais não passam de… mais exames. Atualmente, deveremos não apenas nos perguntar se um novo teste é preciso (evidência orientada para a doença), mas também se o uso do teste melhora os resultados clínicos. Esse é um dos poucos estudos que faz isso. Os autores desse estudo, patrocinados pelo fabricante dos kits de exame, identificaram 534 adultos que se apresentaram em um pronto-socorro canadense com dispnéia. Os pacientes portadores de doença renal avançada, infarto agudo do miocárdio, neoplasia e dispnéia devida a fatores “clinicamente evidentes” tais como pneumotórax ou trauma torácico, foram excluídos, deixando 502 pacientes no estudo final. Foi pedido ao médico de emergência que fizesse o diagnóstico de presença ou não de insuficiência cardíaca sem o conhecimento nos níveis de PNB. Os pacientes foram então aleatoriamente distribuídos para receberem cuidados orientados pelos níveis de PNB ou cuidados sem o conhecimento dos resultados do teste. Os resultados do teste foram fornecidos ao médico de emergência e a todos os médicos envolvidos no cuidado do paciente, e o exame foi repetido 72h após nos pacientes hospitalizados. O diagnóstico final de insuficiência cardíaca (presente em 46% dos pacientes) foi feito por dois cardiologistas que receberam todos os dados clínicos exceto o resultado de PNB (uma vez que ter o conhecimento desse resultado como parte dos padrões de referência enviesaria o estudo e inflacionaria a precisão do teste). Os pacientes foram seguidos por 60 dias com relação a resultados clínicos e econômicos. Os grupos foram equilibrados ao início de estudo e a análise foi por intenção de tratamento. Os pacientes do grupo cujo cuidado foi orientado pelo resultado do PNB tiveram uma estadia mais curta no PS (5,6 versus 6,3 horas; p = 0, 03), menor custo direto total (CAN$ = 5180 versus 6129; p = 0,02), e menos re-hospitalizações (13% versus 20%; p = 0,046). Também houve uma tendência não significativa em direção a uma menor necessidade de testes diagnósticos ambulatoriais, mas não foram encontradas diferenças na estadia no hospital ou nas taxas de mortalidade. Os benefícios foram maiores nos pacientes com uma probabilidade intermediária de insuficiência cardíaca, ou seja, aqueles para os quais o diagnóstico era questionável. Os pesquisadores também monitoraram a precisão do julgamento clínico por si só em comparação com o julgamento suplementado pelo resultado do PNB e descobriram que o teste aumentou a precisão do diagnóstico (área sob a curva característica de operação do receptor = 0,90 versus 0,83, em que 1,0 significa um teste perfeito e 0,5 significa um teste sem utilidade).

Infopoems® oferece ao Global Family Doctor acesso a esta coleção de Poems – (Patient-Oriented Evidence that Matters), las evidencias que são relevantes para os pacientes. São produzidos pela Infopoems® – O sistema de alerta clínico™

Calcio y fracturas

1000 mg calcium/400 IU vit D not very effective for fracture prevention (WHI)
Clinical Question:
Does supplementation with 1000 mg calcium and 400 IU vitamin D reduce the risk of fracture in healthy women?
Bottom Line:
The ability of a small dose of calcium and vitamin D to prevent fractures in healthy community−dwelling women is modest
at best. This study used a relatively low dose of vitamin D (less than the 700 IU to 800 IU found most beneficial in
previous studies), and the patients were generally at low risk of fracture. Perhaps that explains the discordance of these
findings with the bulk of the literature on this topic. (LOE = 1b)
Reference:
Jackson RD, LaCroix AZ, Gass M, et al, for the Women’s Health Initiative Investigators. Calcium plus vitamin D
supplementation and the risk of fractures. N Engl J Med 2006; 354: 669−83.
Study Design:
Randomized controlled trial (double−blinded)
Funding:
Government
Allocation:
Uncertain
Setting:
Population−based
Synopsis:
A previous meta−analysis limited to studies in which women received more than 400 IU of vitamin D found a significant
37% reduction in vertebral fractures (Endocr Rev 2002;23:560−69). In this substudy of the Women’s Health Initiative,
36,282 women were randomized to receive either 1000 mg calcium and 400 IU vitamin D per day or placebo. The study
had 85% power to detect an 18% decrease in hip fractures and 99% power to detect an 18% decrease in total fractures.
The primary outcome was the number of hip fractures and a secondary outcome was total fractures. Fractures of the ribs,
sternum, skull, face, fingers, toes, and cervical vertebrae did not contribute toward the total fracture number. The groups
were balanced at the start of the study, analysis was by intention to treat, and the number of patients who dropped out or
were lost to follow−up was modest (approximately 500 in each group). After a mean of 7 years, there was a
nonsignificant trend toward fewer hip fractures (0.14% vs 0.16% per year; hazard ratio [HR] = 0.88; 95% CI, 0.72 − 1.08)
and a similar nonsignificant trend toward fewer total fractures (1.64% vs 1.70%). The authors did quite a bit of
data−dredging (ie, post−hoc subgroup analyses) and found that if there was any benefit, it was among older women and
women who fell less often. Women who were adherent to the calcium and vitamin D regimen also had fewer hip fractures
(relative risk = 0.71; 95% CI, 0.52 − 0.97). The total intake of calcium and vitamin D from diet and supplements varied
considerably, with no clear trend toward greater benefit in women ingesting more of either substance. Interestingly,
all−cause mortality was lower in the supplement group, although this didn’t quite reach statistical significance (HR = 0.91;
95% CI, 0.83 − 1.01). Not surprisingly, women in the supplement group had 17% more kidney stones. A subgroup also
had regular bone mineral density measurements, which showed greater preservation of bone density among women
taking the supplements.
PMID: 16481635
Delivered as Daily InfoPOEM: 2006−04−05

Fibromialgia

Fibromialgia

En la edición de 15 Julio 2007 de American Family Physician hay una revisión clínica Fibromialgia por Sangita Chakrabarity, MD, MSPH, de Meharry Medical College, Nashville, Tennessee y Roger Zoorob, MD, MPH, de Meharry Medical College y Vanderbilt University, Nashville, Tennessee que inicia: La fibromialgia es un síndrome doloroso idiopático, crónico, no-articular, definido por dolor músculo esquelético diseminado y puntos dolorosos generalizados. Otros síntomas comunes incluyen trastornos del sueño, fatiga, cefalea, rigidez matutina, parestesias y ansiedad. Inicialmente denominado fibrositis, el nombre fue cambiado cuando se hizo evidente que la inflamación no formaba parte del trastorno. Los criterios de 1990 del Colegio Americano de Reumatología para la clasificación de fibromialgia fue el producto del primer estudio multicéntrico bien diseñado y aun continúa siendo un hito para el diagnóstico. La fibromialgia es un síndrome crónico,  idiomático, de dolor  no articular, con puntos dolorosos generalizados. Es una enfermedad multisistémica caracterizada por trastornos del sueño, fatiga, cefalea, rigidez matutina, parestesias y ansiedad. Casi 2% de la población general de USA tiene fibromialgia, estando a riesgo mayor las mujeres de edad mediana. El diagnóstico se basa principalmente en la presencia de 11 puntos dolorosos entre 18 sitios anatómicos específicos. Existen ciertas condiciones co-mórbidas que coinciden con, y también pueden ser confundidas con fibromialgia. Recientemente ha habido mayor reconocimiento y comprensión de fibromialgia. Aunque no existen guías para el tratamiento, hay evidencia de que un enfoque multidimensional puede ser efectivo, con educación del paciente, terapia cognitiva de conducta, ejercicio, terapia física y tratamiento farmacológico.

Para la revisión completa, haga click aquí.
También hay panfletos de información para pacientes:
Fibromialgia: Que es y como manejarla. Para verlo, haga click aquí.
Fibromialgia y Ejercicio. Para verlo, haga click aquí

American Family Physician 15 Julio 2007 76:247-54. 2007 American Academy of Family Physicians.
Fibromialgia, Sangita Chakrabarity, MD, MSPH, y Roger Zoorob, MD, MPH

Categoría. Musculoskeletal. Palabras claves: fibromialgia, dolor crónico, revisión clínica
Sinopsis editado por Dr Linda French, Toledo, Ohio. Colocado en  Global Family Doctor 8 agosto 2007

Fibromialgia

Fibromialgia

En la edición de 15 Julio 2007 de American Family Physician hay una revisión clínica Fibromialgia por Sangita Chakrabarity, MD, MSPH, de Meharry Medical College, Nashville, Tennessee y Roger Zoorob, MD, MPH, de Meharry Medical College y Vanderbilt University, Nashville, Tennessee que inicia: La fibromialgia es un síndrome doloroso idiopático, crónico, no-articular, definido por dolor músculo esquelético diseminado y puntos dolorosos generalizados. Otros síntomas comunes incluyen trastornos del sueño, fatiga, cefalea, rigidez matutina, parestesias y ansiedad. Inicialmente denominado fibrositis, el nombre fue cambiado cuando se hizo evidente que la inflamación no formaba parte del trastorno. Los criterios de 1990 del Colegio Americano de Reumatología para la clasificación de fibromialgia fue el producto del primer estudio multicéntrico bien diseñado y aun continúa siendo un hito para el diagnóstico. La fibromialgia es un síndrome crónico,  idiomático, de dolor  no articular, con puntos dolorosos generalizados. Es una enfermedad multisistémica caracterizada por trastornos del sueño, fatiga, cefalea, rigidez matutina, parestesias y ansiedad. Casi 2% de la población general de USA tiene fibromialgia, estando a riesgo mayor las mujeres de edad mediana. El diagnóstico se basa principalmente en la presencia de 11 puntos dolorosos entre 18 sitios anatómicos específicos. Existen ciertas condiciones co-mórbidas que coinciden con, y también pueden ser confundidas con fibromialgia. Recientemente ha habido mayor reconocimiento y comprensión de fibromialgia. Aunque no existen guías para el tratamiento, hay evidencia de que un enfoque multidimensional puede ser efectivo, con educación del paciente, terapia cognitiva de conducta, ejercicio, terapia física y tratamiento farmacológico.

Para la revisión completa, haga click aquí.
También hay panfletos de información para pacientes:
Fibromialgia: Que es y como manejarla. Para verlo, haga click aquí.
Fibromialgia y Ejercicio. Para verlo, haga click aquí

American Family Physician 15 Julio 2007 76:247-54. 2007 American Academy of Family Physicians.
Fibromialgia, Sangita Chakrabarity, MD, MSPH, y Roger Zoorob, MD, MPH

Categoría. Musculoskeletal. Palabras claves: fibromialgia, dolor crónico, revisión clínica
Sinopsis editado por Dr Linda French, Toledo, Ohio. Colocado en  Global Family Doctor 8 agosto 2007

Efficacy of folic acid supplementation in stroke prevention

Folato previne AVC’s

Questão clínica
A suplementação com ácido fólico previne os AVC’s?

Resumo
Se esses autores identificaram todos os ensaios clínicos relevantes, a suplementação com ácido fólico por pelo menos 36 meses previne os acidentes vasculares cerebrais (AVC’s), especialmente em pacientes sem história prévia.

Nível de evidência: 1 a-

Referência
Wang X, Qin X, Demirtas H, et al. Efficacy of folic acid supplementation in stroke prevention: a meta-analysis. Lancet 2007;369:1876-1882.

Desenho de estudo: meta análise (de ensaios randomizados controlados)

Apoio financeiro: auto financiado ou sem financiamento

Distribuição da amostra: mascarada

Casuística: pacientes ambulatoriais (quaisquer)

Discussão
Esses autores realizaram buscas no MEDLINE e as complementaram buscando as bibliografias dos artigos encontrados e entrando em contato com especialistas na área para identificar ensaio randomizados controlados sobre a suplementação alimentar com ácido fólico para a prevenção dos acidentes vasculares cerebrais. Uma vez que eles não realizaram buscas em outras bases de dados, no entanto, eles podem ter deixado escapar estudos elegíveis. 2 pesquisadores avaliaram a inclusão dos estudos de maneira independente e um terceiro julgou as discrepâncias. Os autores incluíram oito ensaios com 16. 841 pacientes portadores de condições preexistentes tais como AVC anterior, doença arterial coronariana e doença renal terminal. Os estudos duraram entre 24 e 72 meses. As doses de folato variaram entre 0,5 a 15 mg diários. Dois dos estudos foram ensaios abertos. Entre os pacientes que receberam folato, 4,2% tiveram um AVC em comparação com 5,1% dos pacientes-controle (número necessário para tratar = 104; IC de 95%: 63 – 306). Os pacientes, em geral, não tiveram benefício em comparação com o placebo se tratados por menos do que 36 meses ou se tivessem tido um AVC anterior. De maneira interessante, nos países que fortificam os alimentos com ácido fólico (primariamente os EUA e Canadá), os resultados não foram estatisticamente significativos. Finalmente, os autores não realizaram buscas explícitas por estudos não publicados. Uma vez que há um forte viés em direção à publicação de estudos com resultados positivos, esses dados podem estar viciados.