 Ethical aspects. We have tried to minimize possible therapy related side effects to those that are usually observed in the practical clinic. Indeed, all treatments and dosages are those that are usually adopted by general practitioner for the daily practice. Therefore, we do not expect any additional risk for patients that are enrolled in the study. The complications that are associated to thiazide treatment will be prevented by the use of maximal doses that are in the low range of therapeutic effect, and close to the regimen that currently used in daily practice. As for intromission in the private sphere of the patients, the data will be nominally entered in the database by the physician using a loginpassword protected web-based 32bit encrypted connection, and available only for this research purposes after given informed consent by the patients. 