Nordic prescription registers Sweden Morten Andersen Professor Centre for Pharmacoepidemiology, Karolinska Institutet

Essential demographics Size of population: (31 August 2011) Relevant demographic data Statistics Sweden: Drug use data National Board of Health and Welfare tabas click ”Läkemedel” tabas

Relevant host institutions National Board of Health and Welfare (Socialstyrelsen, SoS) Statistics Sweden (Statistiska Centralbyrån, SCB)

Prescription variables What is covered – Dates of prescribing and dispensing – All drug information to package level (some text fields) – Amount dispensed, automated dose dispensing – ATC codes and DDDs – Patient age, sex, region and municipality of residence – Prescriber category, specialty – Drug costs, generic switching What is not covered? – Prescriber (and practice) – Indication – Dose not systematic (text field)

Coverage of prescription database All citizens? Yes Dependent on income? No Dependent on drug? All prescribed drugs dispensed in community pharmacies, not OTC, not in-hospital use Dependent on reimbursement status? No Exceptions? Some nursing homes

Available data on hospitalisation and other variables Data on hospitalisation available from when? – SoS: Patient register (inpatients back to the 70ies, national coverage 1987, outpatients from 2001 depending on region and specialty) Exceptions from coverage? – Not included: Primary care, GPs or specialists, private hospitals Other relevant registers? – Cause of death, Cancer register, Medical birth register: SoS – Migration: SCB – Sociodemographic registers: SCB – Multigeneration register: SCB – Special disease registers: Quality registers – Regional registers (primary care, lab data, hospital use)

Procedures for linkage Describe the entire data retrieval procedure, sequence and variables in the data order Start at SoS defining study population based on drug use an/or hospital data, additional register information Proceed with SCB for migrations and deaths, socioeconomic variables, sampling of control population Return to SoS if necessary e.g. for data on controls Methods for de-identification – Unique person ID generated for each data order – Key can be saved at either SoS or SCB if updates or other linkage is relevant (ask for permission)

Practicalities Whom to approach – A research group who knows the registers… – Ethics committee – The relevant authorities What approvals are required? – Regional ethics committee: English form available, but application must be in Swedishhttp:// – From the authorities providing the data Can data be transferred? – Yes, specify in ethics applications and application for data retrieval Costs – Ethics 5000 SEK – Data depending on procedure and population size, SEK? Time – Ethics 1-2 months, data retrieval 3-6? months

Webpages National Board of Health and Welfare (Socialstyrelsen, SoS) – Registers in general – Prescribed drug registerhttp:// medelsregistrethttp:// medelsregistret – Data ordershttp:// talladataforforskninghttp:// talladataforforskning Statistics Sweden (Statistiska Centralbyrån, SCB) – Research data

A few examples of papers Wettermark B, Hammar N, Fored CM, Leimanis A, Otterblad Olausson P, Bergman U, Persson I, Sundström A, Westerholm B, Rosén M. The new Swedish Prescribed Drug Register--opportunities for pharmacoepidemiological research and experience from the first six months. Pharmacoepidemiol Drug Saf Jul;16(7): Wettermark B, Persson A, von Euler M. Secondary prevention in a large stroke population. A study of patients’ purchase of recommended drugs. Stroke 2008;39: Epub 2008 Aug 7. Weitoft GR, Rosén M, Ericsson O, Ljung R. Education and Drug Use in Sweden--A Nationwide Register-Based Study. Pharmacoepidemiol Drug Saf 17, no. 10 (2008): doi: /pds Jonasson JM, Ljung R, Talbäck R, Haglund B, Gudbjörnsdòttir S, Steineck G. Insulin Glargine Use and Short-Term Incidence of Malignancies-A Population-Based Follow-Up Study in Sweden. Diabetologia 52, no. 9 (2009): doi: /s Bodén R, Brandt L, Kieler H, Andersen M, Reutfors R. Early Non-Adherence to Medication and Other Risk Factors for Rehospitalization in Schizophrenia and Schizoaffective Disorder. Schizophrenia research (2011)doi: /j.schres