Adherence to the major classes of anthypertensive theraphy (AMCA)

Study type

• Study topic:
  Human medicinal product
• Study topic, other:
  Persistence
• Study type:
  Non-interventional study
• Scope of the study:
  Disease epidemiology

  Drug utilisation

  Effectiveness study (incl. comparative)

Non-interventional study

• Non-interventional study design:
  Cohort

  Other
• Non-interventional study design, other:
  Prescription event monitoring

Study drug and medical condition

• Anatomical Therapeutic Chemical (ATC) code:
  (C03AA) Thiazides, plain

  Thiazides, plain

  (C03BA) Sulfonamides, plain

  Sulfonamides, plain

  (C08CA) Dihydropyridine derivatives

  Dihydropyridine derivatives

  (C09A) ACE INHIBITORS, PLAIN

  ACE INHIBITORS, PLAIN

  (C09BA) ACE inhibitors and diuretics

  ACE inhibitors and diuretics

  (C09BB) ACE inhibitors and calcium channel blockers

  ACE inhibitors and calcium channel blockers

  (C09C) ANGIOTENSIN II RECEPTOR BLOCKERS (ARBs), PLAIN

  ANGIOTENSIN II RECEPTOR BLOCKERS (ARBs), PLAIN

  (C09DA) Angiotensin II receptor blockers (ARBs) and diuretics

  Angiotensin II receptor blockers (ARBs) and diuretics

  (C09DB) Angiotensin II receptor blockers (ARBs) and calcium channel blockers

  Angiotensin II receptor blockers (ARBs) and calcium channel blockers
• Medical condition to be studied:
  Essential hypertension

Population studied

• Short description of the study population:
  People ≥ 40 years old with uncomplicated hypertension in Sweden
• Age groups:
  Adults (18 to < 46 years)

  Adults (46 to < 65 years)

  Adults (65 to < 75 years)

  Adults (75 to < 85 years)

  Adults (85 years and over)
• Estimated number of subjects:
  600000

Study design details

• Main study objective:
  To explore if persistence is associated to initial drug class of antihypertensive, when treating uncomplicated hypertension.
• Outcomes:
  Persistence to different classes of antihypertensives.
• Data analysis plan:
  The classes of antihypertensive medication will be compared using a Poisson regression model. The cohort in this study is recruited over a number of years, individuals are of different ages at baseline and the time from the first prescription may be of interest. Poisson models allow for multiple timescales to enter the model simultaneously and the connection between the Cox model and Poisson regression using time-split data is well known. Poisson models also allow treatment-timescale interaction, also known as non-proportional hazards, to be studied using interaction terms. Follow-up time within each individual will be split into intervals of 3 months in which the outcome rate is assumed to be constant. A change of state also splits follow-up time at the time of the event. All timescales will be modeled using cubic splines with five knots