MEDALZ study

MEDALZ (MEDication use and ALZheimer's disease) is a nationwide cohort study, including all community-dwelling persons diagnosed with Alzheimer's disease (AD) in Finland during 2005-2011 (n=70,718). Comparison persons matched with age, gender and region of residence have been identified for each case. The data has been linked to multiple Finnish registers:

  • Prescription register (1995-2012) from Social Insurance Institution
  • Special reimbursement register (1972-2012) from Social Insurance Institution
  • Hospital discharge register (1972-2012) from National Institute of Health and Welfare
  • Causes of death register (2005-2012) from Statistics Finland
  • Socioeconomic data (1970-2012) from Statistics Finland

The database will be updated with follow-up data from these registers.

Effectiveness-related themes in the MEDALZ data include:
1) Drug use in relation to AD diagnosis

2) Drug use, socioeconomic factors and diseases as risk factors for Alzheimer's disease
3) Adverse outcomes associated with drug use (including hip fractures, stroke, mortality, brain injuries, hospital days)

4) Health care service use and costs associated with adverse drug events

5) Health care service use and costs in relation to AD diagnosis, including accurate time of AD diagnosis and appropriateness of care

6) Mortality related to Alzheimer's disease, and to adverse outcomes

7) Methodological development of register-based research, including modelling of drug exposure from Prescription register data

The MEDALZ is the largest cohort of persons with clinically verified diagnoses of Alzheimer's disease in the world.  As persons with Alzheimer's disease are frequent users of health care services evaluation of appropriateness of their care is crucial in optimizing the service use in future as the population with Alzheimer's disease increases rapidly. Our research aims to provide important information on risk factors of Alzheimer's disease, improve the quality of life of AD patients, decrease healthcare expenses that are due to adverse drug events in this vulnerable population, and aid in efficient planning and targeting of healthcare resources.


MEDALZ-2005 is a nationwide cohort study, including all community-dwelling persons with verified Alzheimer's disease (AD) diagnosis residing in Finland on December 31, 2005 (n=28 093) and a single age-, gender and region of residence-matched comparison person without AD for each AD case. The data has been linked to prescription register, as well as hospital and social institution discharge registers (years 2002-2009). The database has been updated with data from prescription register (since 1994), and hospital and social institution discharge registers (since 1972 and 1995 respectively).

The data was used to assess:
1) persistence and changes in medication use after AD diagnosis
2) health status before and after AD diagnosis
3) medication use and its associations with adverse outcomes (mortality, hip fractures, cardio- and cerebrovascular events) in AD patients
4) use of social and healthcare services

MEDALZ-2005 was in many ways a pilot study for the ongoing MEDALZ-study. Findings from the MEDALZ-2005 study have been published in international peer-reviewed journals. In addition, PhD theses utilising this data are under preparation. MEDALZ-2005 is funded by the strategic funding provided by the Faculty of Health Sciences of University of Eastern Finland.