Monday, 12 November 2018

Should we statinize society?








A 2011 Cochrane review concluded that there was not enough evidence to prescribe statins for people with a cardiovascular risk of less than 20% in 10 years, a claim that was consistent with the British NICE guideline (2006-2008) and with the American Heart Association (2011). The surprise came when, unexpectedly, the 2013 Cochrane review changed its mind and lowered the statin threshold to the 10% risk at 10 years, a recommendation that was quickly adopted by the NICE guidelines.

Strongly opposed to this change of approach, John Abramson (Harvard Medical School), and collaborators, in "Should people at low risk of cardiovascular disease take a statin?" ensure that with the criteria of 2011, in the population over 60 years, it would have been necessary to statin 16% of women and 48% of men, but with the recommendations of 2013 the market was extended to practically all the population of older people, given that age is the most influential cardiovascular risk variable in risk calculators. The authors have reviewed the meta-analysis that led to the change of criteria ("The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomized trials") and have reached conclusions that contradict the Cochrane recommendations of 2013:
  1. Of every 140 low-risk people who take statins for 5 years, only one will benefit from avoiding a myocardial infarction or stroke.
  2. 20% of people who take statins have adverse effects, some of them considered as myopathies or diabetes.
  3. In people of low risk, the use of statins implies a small improvement in the reduction of vascular complications, without translation in mortality, which doesn’t compensate the extent of the undesirable effects.
  4. Physicians should forget statinizing people at low risk and should, instead, focus on the lifestyle factors (exercise, smoking and diet) of their patients, which accumulate 80% of the risk.

At the "Preventing Overdiagnosis" Congress (2017), Abramson and two of his collaborators, Rosenberg and Wright, organized a workshop where they shared the update of their work on the medicalization of cardiovascular risk prevention. From the researchers’ explanation, I have prepared a compilation in four points, which I think contribute many elements in such a key debate about the excesses of the medicalization of people's lives:

a) Older people have a more or less long life regardless of their cholesterol levels. A systematic review has shown that in people older than 60 years, the LDL cholesterol level is inversely related to mortality. This finding dismantles the cholesterol theory.

b) The accuracy of the risk scales has been poorly evaluated. It’s thought that calculators tend to fall short in the high risk groups and long in the low risk groups. Clinicians should know the limitations of the measurement instruments they use.

c) There’s no absolute finding that the systematic practice of cardiovascular risk assessment improves clinical effectiveness.

d) Contrary to current belief, the relative benefit that statins can provide is not a constant that affects all people equally. The level of risk, age and gender vary its effects.

Medicalising high-risk people is an initiative that, according to the evidence, can bring a lot of value, but the recommendations to lower both the risk threshold, with such a scarce scientific support medicalizes in an inadequate way to many people, when in fact what they should to do is to go more to the greengrocers, to the gymnasiums and promote a positive spirit towards life.

As Margaret McCartney says, people decide things, apart from planners, for many reasons. Many stop taking statins because of the adverse effects they notice, or simply because they get tired, others reject the proposal because they are not in favour of thinking in terms of avoiding long-term risks, while some claim them, want maximum security, on the margin of their risk levels.

However that may be, let’s not forget that adherence to statins reaches barely 50% per year and, among those over 65, to 25% after two years: a clear reflection of the disagreement between the clinical practice guidelines and the value that patients give to their doctors’ advice.


Jordi Varela
Editor

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