The objective of the project is the constitution of a population-based cohort of 500 persons with severe or morbid obesity (BMI over 35 kg/m2) with annual follow-up for 10 years. It aims to improve the physiopathological, epidemiological and prognostic knowledge of obesity and its consequences. Clinical data, biological material, exams and questionaires will be collected and stored, allowing the realisation of research works, initiated by research teams from our hospital or from other settings.

The objective of this observational study is the follow-up of a cohort of 500 adult persons with morbid obesity (BMI>35 kg/m2).

Clinical and paraclinical data, and biological samples (plasma, serum, DNA, RNA, cell blood, for persons undergoing bariatric surgery (specific consent): samples of liver and adipocytes) will be collected and stored during the follow-up visits. These visits take place at inclusion, at 6 months, twelve months and every year for ten years. The collection of parental DNA will be proposed when feasable for genetic studies.

Persons will be recruited for four years, with an expected number of 350 persons included, in the clinical research unit of Louis MOURIER university hospital (AP-HP).

Each person included will participate in the study for ten years. When included, patients agree to come every year to follow-up visits. They are informed that data collected will be used only for research on obesity and its health consequences.

Inclusion Criteria:

• BMI>35

Exclusion Criteria:

• previous bariatric surgery
• pregnancy

Morbidly obese subjects