Include participants who intend to practice Ramadan fasting and accept to complete the three part of the study .

All volunteers and stable patients that intend to fast ramadan. Each participant is examined during three separate visits.

1. The week before Ramadan (Pre-R).
2. the last week of Ramadan (R).
3. the last week of the month following Ramadan (Post-R). Participants that miss one appointement or more are exluded from the study. Patient recrutement is conducted in primary care centers of the state of Monastir, out-patients clinic (Cardiology, Endocrinology) at the emergency department of Fattouma Bourguiba university hospital after a clarified written consent.

All patients benifit of an endothelial peripheral arterial tonometry (Endo-PAT) test .

Inclusion Criteria:

• Adult patient intending to fast Ramadan.

Exclusion Criteria:

• Age < 18 years old
• Hemodynamic instability.
• Myocardial infarction requiring urgent revascularization.
• Parkinsonism: tremor problem.
• Refusal, communication problem.

Stable patients that intend to fast Ramadan. Each participant is examined during three planned visits. The first takes place during the month preceding Ramadan. The second during the last week of Ramadan and the third thirty days after the end of Ramadan.

Participants that miss one appointement or more are exluded from the study. Patient recrutement is conducted in primary care centers of the state of Monastir, out-patient clinic (Cardiology, Endocrinology) at the emergency department of Fattouma Bourguiba university hospital after a clarified written consent.