Inclusion criteria:

1. Individuals aged between 6 and 25 years;
2. Diagnosed with a chronic childhood condition/disease associated with an increased risk of early cardiovascular disease;
3. Provided informed consent (if over 18 years old) or had informed consent provided by their legal guardian (if under 18 years old) following appropriate information about the study.

Chronic childhood conditions/diseases associated with increased risk of early cardiovascular disease are defined according to the 2019 American Heart Association recommendations (https://doi.org/10.1161/CIR.0000000000000618), as well as other conditions/diseases for which at least two large-scale epidemiological studies have demonstrated an increased risk of cardiovascular disease.

Exclusion criteria:

1. Severe intellectual and developmental disability;
2. Decompensated heart failure;
3. Severe primary immunodeficiency;
4. Ongoing intravenous chemotherapy;
5. Infectious diseases posing a public health risk; or
6. History of regular alcohol or drug use.