Evidence-based Medicine, Studies and High Blood Pressure

Key terms for studies:

• Randomized: Who receives a treatment is chosen at random.
  
  
• Placebo-controlled: A dummy medication or sham treatment prevents the participant from knowing whether they are actually receiving the medication or treatment.
  
  
• Double-blind: Neither the participant nor the researcher knows who receives the placebo and who receives a dummy medication or sham treatment.
  
  
• Statistical significance: A study is significant when it can be determined with statistical certainty that the effect cannot be explained by chance.
  
  
• Effect size: Effect size indicates how well the treatment works. Suppose there were a new medication for high blood pressure that lowered it by only 1 mmHg. The effect would then be very small and, despite possibly being statistically significant, the medication would probably not be recommended.

Problems

1. Study quality
   Unfortunately, it is sometimes still difficult. As mentioned above, the gold standard is a randomized, placebo-controlled double-blind study. Suppose you want to study a particular surgical technique. You can perform a sham operation and make the patient believe they were operated on even if they weren't. But the surgeon knows whether they actually operated or not. That alone is enough to bias the results.
   
   When studying therapies like psychotherapy or physiotherapy, you have the same problem. The therapist knows whether they are delivering the real therapy or a sham one. And participants are likely to notice that as well.
   
   If you study an app, blinding is not possible at all. That means the evidence supporting an app can never be established beyond doubt. Interest groups exploit this to oppose prescription apps. The necessary studies become bloated and more expensive without guaranteed approval. Even if approved, the costs of such an app can be disproportionate to the potential benefit.
   
   
2. Individual differences
   Studies are designed for the average person. But there is no such thing as an average person. When the American military tried to define how a cockpit should be designed in the last millennium, they measured hundreds of people and used those measurements to define the "average" person. The surprising result: not a single participant matched the average exactly. Cockpits were then made adjustable simply because people are different.
   
   Applied to blood pressure:
   Imagine an active ingredient that lowers blood pressure in 5% of participants, but you don't know which ones or why. As long as that's the case, you couldn't conduct a study demonstrating that the active ingredient has an effect. The average effect across patients would be too small.
   Practical problems: Your doctor has a selection of well-studied medicines they could prescribe for you. So, in theory, controlling blood pressure with medication shouldn't be a problem. In practice, things are different. Everyone reacts differently. Some medicines simply don't work or cause side effects, no matter how strong the evidence is.
   
   
3. Limited data availability or poor data
   For some medical questions, there may not be enough evidence, either because of a lack of research or because of ethical or practical limitations. A concrete example in high blood pressure is differences in how blood pressure is measured. It matters how, where, and by whom it is measured. There was a large study called SPRINT whose results led to lower hypertension thresholds in the U.S. The problem was that the measurements were done differently from what had been customary in previous studies. In Europe, therefore, no change in practice was judged necessary.

1. Unique patient cases: If a patient has a unique, complex, or rare disease or set of symptoms, it may be necessary to deviate from general evidence-based guidelines and make individual medical decisions.
   
   
2. Potential for innovation: In some cases, new treatment approaches or technologies may be promising and have the potential to significantly improve patient outcomes, even though they have not yet been sufficiently supported by evidence.
   However, particular caution is required here. New procedures may also entail considerable risks and adverse side effects. The Contergan tragedy between 1957 and 1962 serves as a reminder of this (https://de.wikipedia.org/wiki/Contergan-Skandal).
   
   
3. Traditional or alternative healing methods: One area in which evidence-based medicine may be departed from is traditional or alternative healing methods that have a long history but often lack sufficient scientific evidence of their effectiveness. Many of these methods, such as herbal medicines or certain therapies, have been used for generations and may have a positive effect on health. Although they may not meet the strict criteria of evidence-based medicine, they can be considered as complementary treatments. This is particularly the case if patients prefer them and they have no harmful effects. In such cases, it is important to maintain open communication between doctors and patients and to work together to develop the best possible treatment strategy, taking into account both the patient's wishes and preferences and the effectiveness and safety of the treatment.

Conclusion:

• High blood pressure - Arterial hypertension
• Additional Medications for Treating High Blood Pressure
• Mineralocorticoid receptor antagonist (MRA)
• Diuretics (water pills)
• Calcium channel blockers