title: Allergen sensitization linked to climate and age, not to intermittent-persistent rhinitis in a cross-sectional cohort study in the (sub)tropics.
abstract: BACKGROUND
  Allergen exposure leads to allergen sensitization in susceptible individuals and this might influence allergic rhinitis (AR) phenotype expression. We investigated whether sensitization patterns vary in a country with subtropical and tropical regions and if sensitization patterns relate to AR phenotypes or age.
  
  
  METHODS
  In a national, cross-sectional study AR patients (2-70 y) seen by allergists underwent blinded skin prick testing with a panel of 18 allergens and completed a validated questionnaire on AR phenotypes.
  
  
  RESULTS
  628 patients were recruited. The major sensitizing allergen was house dust mite (HDM) (56%), followed by Bermuda grass (26%), ash (24%), oak (23%) and mesquite (21%) pollen, cat (22%) and cockroach (21%). Patients living in the tropical region were almost exclusively sensitized to HDM (87%). In the central agricultural zones sensitization is primarily to grass and tree pollen. Nationwide, most study subjects had perennial (82.2%), intermittent (56.5%) and moderate-severe (84.7%) AR. Sensitization was not related to the intermittent-persistent AR classification or to AR severity; seasonal AR was associated with tree (p < 0.05) and grass pollen sensitization (p < 0.01). HDM sensitization was more frequent in children (0-11 y) and adolescents (12-17 y) (subtropical region: p < 0.0005; tropical region p < 0.05), but pollen sensitization becomes more important in the adult patients visiting allergists (Adults vs children + adolescents for tree pollen: p < 0.0001, weeds: p < 0.0005).
  
  
  CONCLUSIONS
  In a country with (sub)tropical climate zones SPT sensitization patterns varied according to climatological zones; they were different from those found in Europe, HDM sensitization far outweighing pollen allergies and Bermuda grass and Ash pollen being the main grass and tree allergens, respectively. Pollen sensitization was related to SAR, but no relation between sensitization and intermittent-persistent AR or AR severity could be detected. Sensitization patterns vary with age (child HDM, adult pollen). Clinical implications of our findings are dual: only a few allergens -some region specific- cover the majority of sensitizations in (sub)tropical climate zones. This is of major importance for allergen manufacturers and immunotherapy planning. Secondly, patient selection in clinical trials should be based on the intermittent-persistent and severity classifications, rather than on the seasonal-perennial AR subtypes, especially when conducted in (sub)tropical countries.
authors: Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico.
authors: Désirée
authors: D
authors: Larenas-Linnemann
authors: Institute of Medical Statistics, Informatics and Epidemiology (IMSIE), University of Cologne, Cologne, Germany ; University of Cologne, Cologne, Germany.
authors: Alexandra
authors: A
authors: Michels
authors: Institute of Medical Statistics, Informatics and Epidemiology (IMSIE), University of Cologne, Cologne, Germany ; University of Cologne, Cologne, Germany.
authors: Hanna
authors: H
authors: Dinger
authors: Institute of Medical Statistics, Informatics and Epidemiology (IMSIE), University of Cologne, Cologne, Germany ; University of Cologne, Cologne, Germany.
authors: Kijawasch
authors: K
authors: Shah-Hosseini
authors: Institute of Medical Statistics, Informatics and Epidemiology (IMSIE), University of Cologne, Cologne, Germany ; University of Cologne, Cologne, Germany.
authors: Ralph
authors: R
authors: Mösges
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Centro Regional de Alergia e Inmunología Clínica, Hospital Universitario "Dr. José Eleuterio González" de la Universidad Autónoma de Nuevo León, Monterrey, Nuevo León.
authors: Alfredo
authors: A
authors: Arias-Cruz
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico.
authors: Marichuy
authors: M
authors: Ambriz-Moreno
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Servicio de Alergia e Inmunología Clínica, División de Medicina Interna, Hospital Civil de Guadalajara "Dr. Juan I. Menchaca" Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
authors: Martín Bedolla
authors: MB
authors: Barajas
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; CEINTAP (centro de investigación y tratamiento del asma pediátrico), Hospital Regional de Alta Especialidad del Niño. Dr. Rodolfo Nieto Padrón, Villahermosa, Tabasco, Mexico.
authors: Ruth Cerino
authors: RC
authors: Javier
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico.
authors: María
authors: M
authors: de la Luz Cid Del Prado
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Clinica Santa Cruz, Villahermosa, Tabasco.
authors: Manuel Alejandro Cruz
authors: MA
authors: Moreno
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Allergy Department, Hospital Infantil de Tamaulipas, Cd.Victoria, Tamaulipas, Mexico.
authors: Roberto García
authors: RG
authors: Almaráz
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Inmunología y Alergia, UMAE Hospital de Especialidades, CMNO, IMSS, Guadalajara, Jalisco, Mexico.
authors: Cecilia Y
authors: CY
authors: García-Cobas
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Allergy Department, Hospital Médica Tec 100, Querétaro, Querétaro, Mexico.
authors: Daniel A
authors: DA
authors: Garcia Imperial
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico.
authors: Rosa Garcia
authors: RG
authors: Muñoz
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Servicio de Alergia e Inmunología Clínica, División de Medicina Interna, Hospital Civil de Guadalajara "Dr. Juan I. Menchaca" Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
authors: Dante
authors: D
authors: Hernández-Colín
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Centro de Diagnostico y Tratamiento de Enfermedades Alérgicas y Asma de Toluca, Toluca, Estado de México.
authors: Francisco J
authors: FJ
authors: Linares-Zapien
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Inmunología y Alergia, UMAE Hospital de Especialidades, CMNO, IMSS, Guadalajara, Jalisco, Mexico.
authors: Jorge A
authors: JA
authors: Luna-Pech
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Allergy and Clinical Immunology Department, Hospital of specializations CMN 'Siglo XXI', Mexico, DF, Mexico.
authors: Juan J
authors: JJ
authors: Matta-Campos
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico.
authors: Norma Martinez
authors: NM
authors: Jiménez
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico.
authors: Miguel A
authors: MA
authors: Medina-Ávalos
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Coordination of evidence based medicine (EBM), Facultad de medicina. Universidad Autonoma de Queretaro, Querétaro, Querétaro, Mexico.
authors: Alejandra Medina
authors: AM
authors: Hernández
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico.
authors: Alberto Monteverde
authors: AM
authors: Maldonado
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico.
authors: Doris N
authors: DN
authors: López
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Clinical immunology & allergy department, Clínica Hospital San Jose, Cd.Obregón, Sonora, Mexico.
authors: Luis J
authors: LJ
authors: Pizano Nazara
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Allergy and immunology department, General Hospital of Cancun "Dr. Jesus Kumate Rodriguez', Cancun, Quintana Roo, Mexico.
authors: Emmanuel Ramirez
authors: ER
authors: Sanchez
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Servicio de Alergia e Inmunología Clínic, Seguro Social, Hospital General de Zona No2, Potosí, Potosí, Mexico.
authors: José D
authors: JD
authors: Ramos-López
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Pediatrics and Immunology, Autonomous university of Tamaulipas, H.Matamoros, Tamaulipas, Mexico.
authors: Noel
authors: N
authors: Rodríguez-Pérez
authors: Mexican Study Group on Allergic Rhinitis and Skin Sensitivity. Hospital Médica Sur, Torre 2, cons.602, Puente de Piedra 150, Colonia Toriello Guerra; Delegación Tlalpan, México, DF 14050, Mexico ; Hospital Star Médica Mérida, Mérida, Yucatan, Mexico.
authors: Pablo G
authors: PG
authors: Rodríguez-Ortiz
keywords: Allergic rhinitis; Allergic sensitization; House dust mite; Intermittent rhinitis; Perennial; Persistent rhinitis; Pollen; Seasonal; Skin prick test