The Northern Sweden MONICA Study

Summary

Strengths See above. The strong MONICA network, involving 13 professors and more than 10 other senior researchers in northern Sweden ensures collaboration in a vast national and international network and that the continued activities of the project are not dependent on the commitment of single individuals. The seven PhD students presently using MONICA data will guarantee the long time survival of the project. Weaknesses The participation rates have been 69-81%. Subjects donated samples to the Northern Sweden Biobank. After 25 years since the start of the study, participants are starting to suffer from stroke, infarctions and diabetes in a rapidly increasing rate. We have successfully matched the event registers with population survey data, thereby creating a cost-effective prospective study design for MI, stroke and diabetes. Data from the three data bases has been used in more than 85 original studies and 14 dissertations since 2007. Increasingly other fields have been explored such as infectious diseases, nutrition and environmental toxins.

Type of data

Data Source
Registry + Survey

Type of Study
Survey different
Crosssection occasional

Data gathering method
Registries
Self administered questionnaire
Other: medical tests/diagnosis

Access to data

Conditions of access
As evident the MONICA databases are extensively used by a large number of researchers locally, nationally and internationally. External users of the databases are invited for collaborative work. Throughout the existence of MONICA, very few proposals for usage of MONICA data have been turned down, if so always for quality reasons. We have had contacts with SND in order to plan a registration of MONICA with the SND initiative. MONICA data from previous risk factor surveys are also available in a condensed form on our website. Two booklets containing key data, catering to the general population and politicians has been published and numerous meeting with media, patient’s consumer organisations, politicians and professional organisations have been performed where data pertinent to public health have been presented and discussed.

Type of available data (e.g. anonymised microdata, aggregated tables, etc.)

Formats available
SPSS and excel (bio samples).

Coverage

Coverage Years of collection, reference years, and sample sizes
The Northern Sweden MONICA Study started with the WHO MONICA Study in 1985. The purpose was to monitor trends in mortality and morbidity in cardiovascular disease and relate them to trends in risk factors. Since 1985 21,000 strictly validated stroke events and 18,000 myocardial infarctions have been included in two registers. During the same period, six population based surveys have been taking place, the latest in 2009. Ever since the start of the WHO MONICA Projects, strict and uniform standards have been used for sampling and examinations and database procedures. Biological measurements have undergone continuous quality assurance programmes. Questionnaires are kept consistent throughout the surveys with similar categorisation and definitions, i.e. level of education and presence of hypertension. We are continuing the regular population surveys with 5-year intervals, the seventh survey is to take place in 2014. The MI registry will be merged with the stroke register thus giving an opportunity to study the total burden of cardiovascular disease within a single database. The MONICA cohort based on six cross-sectional population-based surveys provides a unique foundation for describing trends of socio-economic and biochemical risk factors in the population. There are 8 datasets with the following characteristics: Dataset 001: The Northern Sweden MONICA Study 1986 1625 cases. 81% response frequency. 1985 (Field) 1985 (Clinical examination) 1985 (Self-completed questionnaire: Paper/pencil) 1985 (Extracts from registers) A randomised sample of 2000 persons in ages 25-64 were invited to participate in the 1986 study. Dataset 002: The Northern Sweden MONICA Study 1990 1583 cases. 79% response frequency. 1990 (Field) 1990 (Clinical examination) 1990 (Self-completed questionnaire: Paper/pencil) 1990 (Extracts from registers) A randomised sample of 2000 persons in ages 25-64 were invited to participate in the 1990 study. Dataset 003: The Northern Sweden MONICA Study 1994 1921 cases. 77% response frequency. 1994 (Field) 1994 (Clinical examination) 1994 (Self-completed questionnaire: Paper/pencil) 1994 (Extracts from registers) A randomised sample of 2500 persons in ages 25-74 were invited to participate in the 1994 study. Datset 004: The Northern Sweden MONICA Study 1999 1823 cases. 73 response frequency. 1999 (Field) 1999 (Clinical examination) 1999 (Self-completed questionnaire: Paper/pencil) 1999 (Extracts from registers) A randomised sample of 2500 persons in ages 25-74 were invited to participate in the 1999 study. Dataset 005: The Northern Sweden MONICA Study 2004 1905 cases. 76% response frequency. 2004 (Field) 2004 (Clinical examination) 2004 (Self-completed questionnaire: Paper/pencil) 2004 (Extracts from registers) A randomised sample of 2500 persons in ages 25-74 were invited to participate in the 1986 study. Dataset 006: The Northern Sweden MONICA Study 2009 1729 cases. 69% response frequency. 2009 (Field) 2009 (Clinical examination) 2009 (Self-completed questionnaire: Paper/pencil) 2009 (Extracts from registers) A randomised sample of 2500 persons in ages 25-74 were invited to participate in the 2009 study. Dataset 007: The MONICA Myocardial Infarction Registry 18000 cases. Everyone who had a verified myocardial infarction in Norrbotten and Västerbotten in 1985. In 1985-1999 25-64 years-old were included, after that 25-74 years-old. Dataset 008: The MONICA Stroke Registry 21000 cases. People aged 25-74 years residing in Norrbotten or Västerbotten Counties who suffered a stroke has since 1985 been registered in the stroke registry.

First year of collection
1986

Stratification if applicable
regional sample

Base used for sampling

Geographical coverage and breakdowns
Norrbotten and Västerbotten Counties/north Sweden

Age range
Individuals aged 25 – 74 years of age

Statistical representativeness
Regional representative, please specify

Coverage of main and cross-cutting topics
The Northern Sweden MONICA Study is unique among Swedish registers in combining consistency over time (more than 25 years), broadness in data collection (comprehensive questionnaire data, health examinations, blood sampling) and coverage of cardiovascular determinants as well as end-points. As the MONICA cohorts are aging, a large share of the participants are now entering ages when they are prone to be affected by cardiovascular disease and other severe disorders of the elderly. The value of the project is therefore rapidly increasing. One of the strong features of the MONICA Study is its stability over time. Some of the applicants and collaborators have been involved in the project since the late eighties. The Västerbotten and Norrbotten county councils are formally responsible for incidence and population survey registers, and have provided partial financial support since the start of the project. It is foreseen that the basic structure of the MONICA population surveys and cardiovascular event monitoring will be unchanged. The main scientific aim is to describe trends and determinants in cardiovascular disease and diabetes in the northern Sweden population. Additional aims of the database with the scientific network linked to it are to provide data for health planning identify etiologic factors of cardiovascular disease and diabetes, characterize the interplay between determinants, and to describe level, time trends, and determinants of exposure to certain environmental pollutants and compare these to other regions.

Linkage

Standardisation
ICD and ADL.

Possibility of linkage among databases

Data quality

Entry errors if applicable

Breaks
No significant breaks.

Consistency of terminology or coding used during collection
High level of consistency

Governance

Contact information
Mats Eliasson and Stefan Söderberg / Department of Public health and Clinical medicine
Umeå university

901 87 Umeå Sweden Phone: +4690-7865000
Email: Stefan.soderberg(at)medicin.umu.se; Mats.elisasson(at)medicin.umu.se
Url: http://snd.gu.se/en/catalogue/study/EXT0042#description; http://www9.umu.se/phmed/medicin/monica/index.php?content=inenglish; http://www9.umu.se/phmed/medicin/monica/

Timeliness, transparency