title: Non-adherence to antihypertensive medication: The role of mental and physical comorbidity.
abstract: BACKGROUND
  Multiple parameters influence adherence to drug treatment, including socio-economic, healthcare, condition, therapy, and patient-related factors. However, studies of the impact of patient-related factors, particularly regarding comorbid conditions, have produced conflicting results.
  
  
  OBJECTIVE
  To analyse the association between mental and physical comorbidity and non-adherence to antihypertensive medication in patients attending primary care, after including a comprehensive range of chronic comorbidities and potential confounders.
  
  
  METHODS
  Cross-sectional study of 113,397 adults with a diagnosis of hypertension in 2010 assigned to the public health service of a region in northeastern Spain. Pharmacy billing records were linked to data from electronic health records at individual level. Non-adherence was defined as an antihypertensive medication possession ratio (MPR) <80%. Multivariable logistic regression models were used to estimate the odds ratio for non-adherence. Potential predictors included mental and physical comorbidity, age, sex, blood pressure level, nationality, rurality, polypharmacy, and number of visits to the GP and to different specialties.
  
  
  RESULTS
  One fifth of the study population showed poor adherence levels. Female sex, younger age, foreign nationality, living in a rural area, low blood pressure levels, polypharmacy, and mental comorbidity were positively and significantly associated with non-adherence. Conversely, non-adherence was negatively and significantly associated with the presence of cardiovascular risk factors and higher annual rates of GP visits.
  
  
  CONCLUSIONS
  The majority of patient-related determinants identified here (e.g., the presence of mental comorbidity, polypharmacy, foreign nationality) underscores the need for a patient- rather than a disease-centred care approach, as well as adequate physician-patient communication.
authors.affiliation: EpiChron Research Group on Chronic Diseases, Aragón Health Sciences Institute (IACS), IIS Aragón, Miguel Servet University Hospital, Paseo Isabel La Católica 1-3, 50009 Zaragoza, Spain; Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Carlos III Health Institute, C/ Sinesio Delgado 4, 28029 Madrid, Spain.
authors.forename: Amaia
authors.initials: A
authors.lastname: Calderón-Larrañaga
authors.affiliation: Department of Global Public Health and Primary Care, University of Bergen, Kalfarveien 31, NO-5020 Bergen, Norway; Norwegian Centre for Minority Health Research (NAKMI), Oslo University Hospital, PO box 4956, NO-0424 Oslo, Norway.
authors.forename: Esperanza
authors.initials: E
authors.lastname: Diaz
authors.affiliation: EpiChron Research Group on Chronic Diseases, Aragón Health Sciences Institute (IACS), IIS Aragón, Miguel Servet University Hospital, Paseo Isabel La Católica 1-3, 50009 Zaragoza, Spain; Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Carlos III Health Institute, C/ Sinesio Delgado 4, 28029 Madrid, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Poblador-Plou
authors.affiliation: EpiChron Research Group on Chronic Diseases, Aragón Health Sciences Institute (IACS), IIS Aragón, Miguel Servet University Hospital, Paseo Isabel La Católica 1-3, 50009 Zaragoza, Spain; Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Carlos III Health Institute, C/ Sinesio Delgado 4, 28029 Madrid, Spain; San Pablo Health Centre, C/ Aguadores 7, 50003 Zaragoza, Spain; University of Zaragoza-Faculty of Medicine, C/ Domingo Miral s/n, 50009 Zaragoza, Spain.
authors.forename: Luis Andrés
authors.initials: LA
authors.lastname: Gimeno-Feliu
authors.affiliation: EpiChron Research Group on Chronic Diseases, Aragón Health Sciences Institute (IACS), IIS Aragón, Miguel Servet University Hospital, Paseo Isabel La Católica 1-3, 50009 Zaragoza, Spain; University of Zaragoza-Faculty of Medicine, C/ Domingo Miral s/n, 50009 Zaragoza, Spain; Dpt. of Health, Welfare and Family, DG Planning and Assurance, Government of Aragon, Vía Univérsitas 36, 50009 Zaragoza, Spain.
authors.forename: José María
authors.initials: JM
authors.lastname: Abad-Díez
authors.affiliation: EpiChron Research Group on Chronic Diseases, Aragón Health Sciences Institute (IACS), IIS Aragón, Miguel Servet University Hospital, Paseo Isabel La Católica 1-3, 50009 Zaragoza, Spain; Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Carlos III Health Institute, C/ Sinesio Delgado 4, 28029 Madrid, Spain; University of Zaragoza-Faculty of Medicine, C/ Domingo Miral s/n, 50009 Zaragoza, Spain.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Prados-Torres
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D003144:Communication Barriers; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology*; D008297:Male; D055118:Medication Adherence; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology*; D008875:Middle Aged; D019338:Polypharmacy
chemical_list: D000959:Antihypertensive Agents
keywords: Antihypertensives; Comorbidity; Medication adherence; Primary health care