The word placebo comes from the Latin placere, which literally means “to please.”
The term placebo is used by both physicians and the general public and usually refers to some treatment or intervention that lacks any effect measurable. However, it has clinically relevant effects in a wide variety of diseases, so it is important to be aware of this phenomenon and not dismiss it as an irrelevant aspect in the practice of science-based medicine.
The word placebo comes from Latin pleasure, which literally means “to please”. The term is used to refer to a pharmacologically inert treatment. In the past, placebo was a therapeutic option for many diseases, due to the lack of effective treatments. Later they became a fundamental part of evidence-based medicine by being the reference comparator in the most clinical trials. Nevertheless, the treatment with placebo it can affect different aspects of multiple diseases in a clinically important way. An example of this is his role in the treatment of osteoarthritis.
The term is used to refer to a pharmacologically inert treatment.
An example: paracetamol in osteoarthritis
Osteoarthritis is one of the diseases in which it has been described in detail The effect placebo. This disease is the most common cause of arthritis and can manifest with joint pain, stiffness, limited functionality, and impaired quality of life.
Despite its prevalence, there is no curative treatment and a great part of symptomatic therapies shows a relatively small effect size (0.31 for pain reduction).
A example of the placebo effect in rheumatology, it is paracetamol, which, although it has been recommended in some guides for the management of osteoarthritis pain, has a practically negligible effect. In contrast, the placebo by itself can result in a significant improvement in osteoarthritis symptoms. On average, patients receiving placebo for the treatment of osteoarthritis report a 75% reduction in pain, a 71% functional improvement and an 83% improvement in stiffness, when compared to patients who received no treatment.
The effect size increases with the aggressiveness of the treatment it is adjusting, with the intensity of pain, and with the invasiveness of administration (eg, injected placebo has been shown to be more effective than a tablet).
Although improvement has been observed in parameters reported by patients, when they are performed measurements such as range of motion, muscle strength and knee circumference, no significant improvements are observed. That is, although there is an improvement in subjective parameters, the objective measurements do not seem to have a similar response.
Therefore, The effect placebo seems like a good adjuvant To conventional therapy, although it does not appear to alter the progression of the disease, it can help patients cope with the symptoms of osteoarthritis.
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