title: Workplace social capital and adherence to antihypertensive medication: a cohort study.
abstract: BACKGROUND
  While hypertension is a common and treatable health problem, adherence to antihypertensive medication remains a challenge. This study examines the hypothesis that workplace social capital may influence adherence to antihypertensive medication among hypertensive employees.
  
  
  RESULTS
  We linked survey responses to nationwide pharmacy records for a cohort of 3515 hypertensive employees (mean age 53.9 years, 76% women) who required continuous antihypertensive drug therapy (the Finnish Public Sector study). A standard scale was used to measure workplace social capital from co-workers' assessments and self-reports in 2000-2004. Non-adherence to antihypertensive medication was determined based on the number of days-not-treated at the year following the survey using comprehensive prescription records. Negative binomial regression models were conducted adjusting for socio-demographic characteristics, duration of hypertension, behaviour-related risk factors, and co-morbid conditions. The overall rate of days-not-treated was 20.7 per person-year (78% had no days-not-treated). Higher age, obesity, and presence of somatic co-morbidities were all associated with better adherence, but this was not the case for co-worker-assessed or self-reported workplace social capital. The rate of days-not-treated was 19.7 per person-year in the bottom fourth of co-worker-assessed workplace social capital, compared to 20.4 in the top fourth. The corresponding rate ratio from the fully-adjusted model was 0.95 (95% confidence interval (CI) 0.58-1.56). In a subgroup of 907 new users of antihypertensive medication this rate ratio was 0.98 (95% CI 0.42-2.29).
  
  
  CONCLUSIONS
  We found no consistent evidence to support the hypothesized effect of workplace social capital on adherence to drug therapy among employees with chronic hypertension.
authors.affiliation: Finnish Institute of Occupational Health, Helsinki, Finland. tuula.oksanen@ttl.fi
authors.forename: Tuula
authors.initials: T
authors.lastname: Oksanen
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawachi
authors.forename: Anne
authors.initials: A
authors.lastname: Kouvonen
authors.forename: Etsuji
authors.initials: E
authors.lastname: Suzuki
authors.forename: Soshi
authors.initials: S
authors.lastname: Takao
authors.forename: Noora
authors.initials: N
authors.lastname: Sjösten
authors.forename: Marianna
authors.initials: M
authors.lastname: Virtanen
authors.forename: Jaana
authors.initials: J
authors.lastname: Pentti
authors.forename: Jussi
authors.initials: J
authors.lastname: Vahtera
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimäki
mesh_terms: D000959:Antihypertensive Agents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D012944:Social Support; D017132:Workplace / Q000706:statistics & numerical data*; D016903:Drug Monitoring
chemical_list: D000959:Antihypertensive Agents