[MUSIC] Dear students, this module will be about the screening of cardiovascular conditions. They will have three parts. The first part will be about the screening of hypertension. The second one about the screening of diabetes. And the third one will be about the screening of cardiovascular risk factor in children. For each of these case studies, I will use the same structure. That is, we will begin by the sections about the burden of disease, followed by the sections about benefits and harms of the treatments for these conditions. I will speak about that issue related to the screening of those conditions. We will finish by should we screen or should we not screen for these conditions. We will finish with some recommendations about the screenings. About the burden of disease, let's begin with hypertension and the burden of disease due to hypertension. Hypertension is a major issue in public health. This is associated with an increased risk of cardiovascular disease. It is one of the major cause of death worldwide. One estimates that about 13 million people die every year due to elevated blood pressure. It is the cause of about more than half of coronary heart disease, and more than half of stroke. So it's a major cause of death in the populations. There is a strong relationships between the level of blood pressure and the risk of disease. On the slide, you can see here, you see the relationship between the diastolic blood pressure and the risk of cardiovascular disease. As you can see, the shape is what we say it's called log-linear relationships, in the sense that you have these proportional increase with the level of blood pressure of the risk of cardiovascular disease. It means that above a given level of blood pressure, the risk become very high as you can see here on this slide. Another way to see that is on this other frame, you see here with colors. When the color is red, as here you can see on the slides, there is a high risk of cardiovascular disease. And when the color is green, there is a low risk of cardiovascular disease. And here, on the left of the scale, you see the level of the pressure and the higher level of the blood pressure, the higher the risk of cardiovascular disease. So you have this relationship between a level of risk and burden of disease. Let's go now to benefits and risk of treatments. There is numerous trials we have shown that reducing blood pressure can prevent the occurrence of cardiovascular disease. And we have more than 60, 70 trials having shown that, though there is a handful of evidence having shown the benefits of that things. It has been shown to reduce the frequency of cardiovascular disease to reduce the cause of death or when you reduce blood pressure, you can reduce the cause of death. So there is a huge benefits well demonstrated of reducing blood pressure. About the risks due to diseases, there is some risk due to treatments. For example, having too low blood pressure, some side effects due to treatment, specific to the treatment. So there is some risk, which is quite well known and above that. If we make the balance between the risks and the benefits, hypertension treatments is recognized to have a good balance between risks and treatments. Here, on the slide, you see the benefits of treatments, and you can see that there is humble evidence shown here by the scale of the treatments, about the benefit of treatments. Is there some issue about the screening of hypertension? There is some. We don't have real trial, having assessed the benefit of screening versus no screenings. We have data on the benefits of treatments, but on the benefits of screening itself, is not so clear about that. Other issue, one major issue with the screening of hypertension is related to the measurement of blood pressure. Blood pressure is highly variables from one minute to the others, from one day to the other, from one month to the others. And here on this slides, you can see on this tables. What will change, for example, when you speak your blood pressure is higher, when you attend a meeting, blood pressure is higher. So you have to account of this variability of blood pressure. And when you make a screen, you have to be sure that the blood pressure we measure are the right ones. So it's a big issue how to measure blood pressure. What is needed sometimes when you make a screening of blood pressure and someone has high blood pressure, you have to confirm that by using what we call ambulatory blood pressure measurement. In here, on the slides, you can see the whole blood pressure is measured over 24 hours on this slides. On the right on the screen, you see that right sometimes you need to use those kind of tools to be sure that the person has elevated blood pressure. So it's one of the big issue with the screening of blood pressure. Another issue with that above which the blood pressure is considered to be too much elevated is that 140 over 90 in that, 120 over 80. So we have to be sure about over which levels we begin to treat. And this is one of the issues. This is an issue which is common to all screening of cardiovascular risk factors. The thresholds above which we have to begin to make a treatment. So we have to consider that, and it's an issue with these screens. There is other issues which you can see on this list and with details about that. That's it for the issue. I will finish with some recommendations, should we screen or not screen ? and all recommendations are going in the same direction. There is strong evidence that we should screen. I give here on these slides the US recommendations and the Canadian recommendations. And both are going the same direction. We should be screened regularly as an adult, regularly. And it's considered to be a relatively high evidence of the benefits of the screening for hypertension. And with this recommendations, let's finish this case study about screening for hypertension. I thank you for your interest. [MUSIC]
