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Mostrando postagens com marcador hipertensão. Mostrar todas as postagens
Mostrando postagens com marcador hipertensão. Mostrar todas as postagens

terça-feira, 8 de abril de 2014

Vitaminas e medicações efervescentes: risco aumentado de doença cardiovascular e morte pelo sódio que contém!

Após o post sobre a inutilidade de polivitamínicos em pacientes hígidos saudáveis (Visualizar), lembrei de mais um diálogo comum relacionado a vitaminas:

Em uma farmácia...
- "Gostaria de uma caixa do remédio X"
- "Aqui está. Mais alguma coisa?"
- "Não. Obrigado."
- "Vamos levar a vitamina C? Hoje está em promoção!"
- "Não. Obrigado."
- "Vamos lá, você compra 2 e leva 3..."


Além de polivitamínicos não trazerem benefícios (a não ser em contextos clínicos específicos ou por avaliação médica), vimos que podem até causar mal, conforme post passado (Visualizar). Mas quando dispostos em formulação efervescente, há ainda um agravante. O sódio presente nas formulações efervescentes se torna um grande vilão. Dessa forma, a vitamina C efervescente (como quaisquer medicações efervescentes) pode aumentar o risco cardiovascular para AVC, hipertensão e infarto do miocárdio, conforme estudo observacional publicado pelo BMJ com mais de um milhão de participantes (Association between cardiovascular events and sodium-containing effervescent, dispersible, and soluble drugs: nested case-control study. BMJ 2013;347:f6954).

Por exemplo, comprimidos efervescentes de 500 mg ou de 1g de Redoxon, Cewin e Cebion possuem entre 250-283 mg de Sódio, o equivalente a cerca de 0,75 g de cloreto de sódio (NaCl), ou seja, três quartos de um saquinho de sal. Se tomar 2 comprimidos de 500 mg, o dobro! Para se ter uma noção comparativa, a Coca-Cola Zero, tão alardeada por ter uma quantidade excessiva de sódio, tem em uma lata de 355 ml cerca de 49 mg de sódio.

Isso não fica só restrito à vitamina C, mas como dito, a todos comprimidos efervescentes, como paracetamol e aspirina. O SONRIDOR tem 427 mg de sódio (!!) e o SONRISAL não explicita diretamente, mas tem 1854 mg de bicarbonato de sódio e 400 mg de carbonato de sódio, o que pelos meus cálculos seria o campeão com o equivale a 660 mg de sódio (!!!) em sua composição, ou seja, bem mais de um saquinho de 1g de sal. A posologia, na bula do Sonrisal, informa a dose máxima de 8 comprimidos efervescentes por dia... Imaginem a sobrecarga de sódio...

Para referência rápida:

1 mmol de sódio = 23 mg de sódio = 58 mg de NaCl (multiplica por 2,52)

Então, grande cuidado para quem tem costume de regularmente tomar esse tipo de medicação! 

Risk of outcome, sodium-containing vs standard formulations group
OutcomeAdjusted* odds ratio (95% CI)
Composite outcome**1.16 (1.12–1.21)
Incident nonfatal stroke1.22 (1.16–1.29)
Hypertension7.18 (6.74–7.65)
All-cause mortality1.28 (1.23–1.33)
*Adjusted for age, sex, body mass index, smoking, alcohol, chronic illness, and use of other medications. **Nonfatal MI, nonfatal stroke, vascular death.

Apesar da limitação do estudo para alguns fatores confundidores como história familiar, sódio da dieta etc, fica o alerta.

Clique abaixo para ver texto do medscape comentando um pouco mais o assunto.

domingo, 9 de março de 2014

Paciente hipertenso de difícil controle: algumas dicas para abordagem inicial

Dicas de como abordar hipertensão refratária


Fonte: lookfordiagnosis.com

Não é incomum encontrar em ambulatórios e unidades básicas de saúde alguns pacientes que se apresentam, via de regra, com níveis pressóricos elevados, alguns até grau III (≥180x110 mmHg - classificação VI Diretrizes Brasileiras de Hipertensão - Arq Bras Cardiol 2010; 95(1 supl.1): 1-51), mesmo com a prescrição de múltiplos antihipertensivos. 

Hipertensão resistente ou refratária é definida como a manutenção de níveis pressóricos inadequados a despeito do uso de 3 ou mais medicações de classes diferentes sendo uma delas um diurético adequado à função renal.

Muitas vezes poderá ser necessário encaminhamento para tratamento especializado, mas antes de encaminhar com esse fim (que no nosso sistema público pode demorar meses), é interessante atentar algumas coisas. Prescrição não é sinônimo de uso adequado de medicações, bem como orientações dietéticas ser não ser sinônimo de aderência a ela. Esses e outros itens seguem abaixo em um algoritmo publicado no Current Cardiology 4ª edição junto a trechos interessantes. É curto e vale a pena ler.





Alguns trechos do texto:

"Resistant hypertension is defined as failure to achieve BP target goal despite three or more drugs, one of which should be a diuretic. The first simple step in managing resistant hypertension, after excluding WCE, nonadherence to medications, and secondary hypertension, is to determine whether patients are on an appropriate class of diuretics based on renal function. Patients with estimated glomerular filtration rate (eGFR) > 50 mL/min/1.73 m2 should be treated with thiazide diuretics, particularly chlorthalidone, rather than loop diuretics because of longer half-life and proven efficacy in lowering BP. Patients with an eGFR of 30–40 mL/min/1.73 m2 or less should be on loop diuretics because the ability of thiazide diuretics to promote diuresis diminishes with impaired renal function. The use of an appropriate drug combination that provides synergistic effect on BP could minimize the number of medications needed to control hypertension. Assessment of hemodynamic variables is also helpful in deciding appropriate drug combination. For example, the use of BBs and a central sympatholytic drug generally yields minimal incremental benefit and is prohibited in patients with bradycardia or heart block. These patients should be treated with vasodilators such as DHP CCBs, ACEIs, ARBs, or hydralazine (Figure 2–2). Patients with elevated resting heart rate are more likely to derive large BP reduction with BBs, diltiazem, or verapamil because elevated heart rate is usually a good indicator for hyperkinetic circulation in hypertensive patients. Addition of spironolactone should also be considered in patients with resistant hypertension despite adjustment of medications, as mentioned earlier. An increasing body of evidence suggests that low-dose spironolactone between 12.5 and 25 mg/day, which is not likely to produce a major diuretic effect, causes a dramatic fall in BP on average of 25/12 mm Hg, when used as add-on therapy in patients with uncontrolled hypertension. Antihypertensive effect of spironolactone is observed even in patients with essential hypertension without an elevated aldosterone-to-renin ratio. Combination of DHP and non-DHP CCBs appears to have additive effects on peripheral vasodilation and BP, possibly due to binding to different sites of the receptors, and should also be considered in these patients. In contrast, addition of an ARB to ACEI has modest effects on BP, on average of only 5/3 mm Hg. The addition of long-acting nitrates may be considered in patients with isolated systolic hypertension who are refractory to treatment because it has been shown to be beneficial in one small study."


Abraços,

domingo, 22 de dezembro de 2013

Novos guidelines de hipertensão arterial sistêmica em adultos (JNC 8) mais lenientes com o controle pressórico

Caros,

Foi publicado no JAMA, em 18 de dezembro, o JNC 8 (2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults - 8th Joint National Committee) com guidelines sobre hipertensão arterial sistêmica em adultos.

Mais conciso e simples em número de páginas (14) e recomendações, aparentemente no estilo "menos é mais", essas atualizações se somam aos novos guidelines de obesidade e ao polêmico guideline de dislipidemia também publicados nesse ano. Lembrem que o último JNC 7 era de 2003!

As principais mudanças foram na leniência no controle pressórico, escolha de medicações e alternativas para hipertensão resistente.

Baixe o PDF aqui.
Baixe o suplemento em PDF aqui.
Baixe um PPT com o algoritmo aqui.
Veja o algoritmo abaixo junto com comentários do MEDSCAPE.




CHICAGO, IL — At long last, the Eighth Joint National Committee (JNC 8) has released its new guidelines on the management of adult hypertension, which contain two key departures from JNC 7 that the authors say will simplify care[1].

For one, the expert writing group recommends a relaxing of the more aggressive JNC 7 target blood pressures and treatment-initiation thresholds in elderly patients and in patients under age 60 with diabetes and kidney disease. JNC 8 also backs away from the recommendation that thiazide-type diuretics should be initial therapy in most patients, suggesting an ACE inhibitor, angiotensin-receptor blocker (ARB), calcium-channel blocker (CCB), or thiazide-type diuretic are reasonable choices.

 We wanted to make the message very simple for physicians.
"Our goal was to create a very simple document," lead author on the new guidelines, Dr Paul A James (University of Iowa, Iowa City), told heartwire . "We wanted to make the message very simple for physicians: treat to 150/90 mm Hg in patients over age 60 and 140/90 for everybody else. And we simplified the drug regimen as well, to say that any of these [four] choices are good, just get people to goal. Monitor them, track them, remonitor them. That's a very simple message."

The 14-page, JNC 8 guidelines include a detailed treatment algorithm and a handy table spelling out key differences between JNC 7 and JNC 8. The authors also published over 300 pages in an online supplement outlining their evidence review process, including reviewer commentary. The guidelines themselves were constructed around three questions, which James notes were developed at the outset of the evidence review: Does initiating therapy at specific BP thresholds improve health outcomes? Does drug treatment to specified goals improve health outcomes? And do different drugs/drug classes differ in benefits and harms?

Nine Recommendations

Those questions then form the basis for nine recommendations, discussed in depth and assigned a score for both the strength of the recommendation and the evidence supporting it. Among the recommendations:
  • In patients 60 years or over, start treatment in blood pressures >150 mm Hg systolic or >90 mm Hg diastolic and treat to under those thresholds.
  • In patients <60 years, treatment initiation and goals should be 140/90 mm Hg, the same threshold used in patients >18 years with either chronic kidney disease (CKD) or diabetes.
  • In nonblack patients with hypertension, initial treatment can be a thiazide-type diuretic, CCB, ACE inhibitor, or ARB, while in the general black population, initial therapy should be a thiazide-type diuretic or CCB.
  • In patients >18 years with CKD, initial or add-on therapy should be an ACE inhibitor or ARB, regardless of race or diabetes status.

A key point, said James, is that while the targets have been loosened, the new guidelines do not mean that physicians should ease up on treatment in a patient who is doing very well based on JNC 7 guidance.

"We wanted to be crystal clear about where the evidence is to support these recommendations. We are not saying that if you've gotten someone's [systolic] BP to 140 or 135 mm Hg on medicine and they are doing well that you need to take them off medicines and get their BP closer to 150. We are simply saying, if you can consistently get people's BP below 150, you really are improving their health outcomes."

He acknowledged that critics will worry that raising the threshold to 150 mm Hg in older subjects will mean real-world blood pressures far greater. James called this the "speed-limit rule," suggesting that no matter what the target is, people will hover above it, rather than being more likely to get patients to goal.

"I do think there's always a concern about people not following the recommended targets; however, we have to start somewhere, and our panel's opinion is that we should start where the evidence leads us," James said. "In one sense, you're fooling people by saying, 'Let's pretend it's 140 mm Hg so we have a little leeway,' and that doesn't feel exactly right."

The Long Wait for JNC 8

Physicians have waited so long for "JNC-Late" it's possible they've forgotten what they were looking for in the first place. Not a bad thing, since the "2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults" is a very different document from JNC 7, published in 2003. While the National Heart, Lung, and Blood Institute (NHLBI) originally commissioned the JNC 8 guidelines and appointed the commission members in 2008, the federal agency announced earlier this year that it was handing off the task of guideline writing to the American College of Cardiology and the American Heart Association (ACC/AHA).

As reported by heartwire , those organizations released four of the formerly NHLBI-sponsored guideline documents last month, swiftly followed by a "scientific advisory" offering "an effective approach to high blood-pressure control," presumably to fill the yawning gap represented by the missing JNC 8 guidelines.

To heartwire , James said that JNC 8 members decided, after the NHLBI announcement, that they were not interested in having ACC/AHA put their imprimatur on the guidelines and opted to press ahead on their own, although all of their interactions with the cardiology organizations were cordial. "They are wonderful organizations, and I have nothing but the utmost respect for the individuals I interacted with," he insisted.

We haven't shopped this guideline around to seek that kind of approval.
Instead, the commission submitted JNC 8 guidelines to the Journal of the American Medical Association and in the paper states: "This report is . . . not an NHBLI-sanctioned report and does not reflect the views of NHLBI."

Asked about the ACC/AHA scientific advisory on hypertension, James said he sees "no relationship between the two documents" and played no part in the other document's development.

"Our intention was to get our guideline out into the public arena, to get peer review, and we purposely have not sought to be endorsed by any professional group or society, any insurance company, or any federal agency. We haven't shopped this guideline around to seek that kind of approval. Our hope is that this guideline will be read and digested and that the societies look at this work and say yes, this is valid work, and we need to follow these guidelines, or no, it's not."

Of note, JNC 8 is mostly in line with the European Society of Hypertension (ESH) guidelines released earlier this year, which suggested a target of <140 mm Hg systolic BP for "all" patients, with some caveats. In patients with diabetes, the ESH guidelines suggest a diastolic BP of <85 mm Hg, and for patients under 80 years, they suggest a target of between 140 and 150, going lower only if the patient is fit and in good health. And joining in on guideline-palooza, the American Society of Hypertension and International Society of Hypertension announced late yesterday that they, too, are releasing new guidance, targeting management of hypertension in the community.

A Chorus of Opinions

JNC 8 is accompanied by three editorials. One, by Dr Harold C Sox (Dartmouth Institute for Health Policy and Clinical Practice, Hanover, NH), addresses the "trustworthiness" of the new hypertension guidelines[2]. Sox points out that the JNC 8 guidance adheres much more closely to quality standards published by the Institutes of Medicine (IOM) in 2011 (Clinical Practice Guidelines We Can Trust) than it does the JNC 7 document: a strength, implies Sox. Most notably, the JNC 8 members published their methods online along with detailed comments from reviewers. In a separate editorial, JAMA editor in chief Dr Howard Bauchner (Boston University School of Medicine, MA) and colleagues note that the guideline documents released by the ACC/AHA "have been met with controversy"—a key complaint being the lack of a transparent peer-review process[3].

Finally, Dr Eric Peterson (Duke University, Durham, NC) and colleagues (all associate or senior editors at JAMA) tackle the "goals and purposes" of hypertension recommendations[4].

Speaking with heartwire , Peterson pointed to the fact that the loosening of targets is as much based on a lack of evidence as it is on new evidence.

"Don't you find it fascinating that high cholesterol and high blood pressure are two of our most prominent risk factors for cardiovascular disease, we've known effective therapies for those two things for 10, 20, and in some cases 30 years, yet we still don't know what the right treatment targets should be, or indeed, whether we should have targets at all?"

As such, he notes, it's striking that the approach taken by the JNC 8 document contrasts sharply with that taken in the new ACC/AHA guidelines on cholesterol. While the latter abandoned treatment goals and recommended a more aggressive approach in elderly patients, JNC 8 has done the opposite: specified treatment targets and advocated a less aggressive approach in the elderly.

"I think this will instill some debate: did they get the thresholds right?" Peterson commented. He hopes it will also spur calls for more research to answer the many questions not addressed in the document.

A final issue, and one also raised by James in his interview with heartwire , is what the new JNC 8 recommendations will mean for performance measures, which have been taken up by insurers and payers to determine benchmarks of care.

"One of the things the panel certainly had to wrestle with was, after JNC 7, one of the unintended consequences was that insurance companies and those who measure quality said every patient needs to have a BP under 140/90," James explained. "So what you have is doctors who want to achieve these BP measures having patients with 126/60 blood pressures, and when you are talking about elderly patients, who are already taking many other medications, taking additional drugs, and having their blood pressures pushed down that low, you have to really question whether you are doing good."

James had no conflicts of interest; disclosures for other members of JNC 8 are listed in the paper. Bauchner and Peterson had no conflicts, nor did their coeditorialists. Sox disclosed serving on IOM committees and having been a member of the Report Review Committee of the National Academies.