1. Centro Médico Nacional Siglo XXI, Department of Endocrinology, Hospital de Especialidades, Instituto Mexicano del Seguro Social, Mexico City 06720, Mexico
2. Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
3. Unidad de Medicina Familiar No. 69, Department of Family Medicine, Instituto Mexicano del Seguro Social, Calle José María Morelos 210-232, Centro, Texcoco 56100, Mexico
4. Endocrine Diseases Research Unit, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City 06720, Mexico