First round of the Oslo-study - Oslo I
About 30,000 men were invited to attend a health screening for tuberculosis during the period of May 1972 until December 1973. In addition, the screening was aimed at getting more information about risk factors for cardiovascular disease (1). The participants answered a 1-page questionnaire on symptoms, diseases and risk factors. Height, weight, and blood pressure were measured. A blood sample taken in the non-fasting state, was used for measurements of total serum cholesterol, triglycerides and glucose.
Almost 18,000 men attended the screening. Some of the attendees were, after additional health examination at the Ullevål University Hospital, invited to participate in a cardiovascular disease risk reduction trial. These persons experienced less cardiovascular disease and a lower mortality rate (2). Others were asked to take part in a study on medication for high blood pressure (3). There have been several follow-up studies of the participants regarding CVD disease and death. (4-7).
As one of the first large screenings in the world we got answers to many questions. We learnt that:
- 40-49 year-old men with high risk could live longer and get fewer diseases if they consumed more low-fat food and stopped smoking (2).
- 40-49 year-old men who were treated for high blood pressure, had reduced number of strokes (3).
- The risk of myocardial infarction was associated with socio-economical status (4).
- Smoking, high blood pressure and little physical activity increase the risk of stroke (5).
- Even small changes in ECG led to an increasing risk of dying from cardiovascular disease. Such findings would improve the chance of identifying persons at risk of heart disease (6).
- The screening improved the possibility to find persons that may get cardiovascular diseases (7).
The Oslo-study was the model study for later population based health studies on cardiovascular risk in Norway. These studies have all contributed much information on risk of myocardial infarction, stroke and diabetes, together with other sufferings and diseases.
Publications from Oslo I study:
- Leren P, Askevold EN, Foss OP, Frøili A, Grymyr D, Helgeland A, Hjermann I, Holme I, Lund-Larsen PG, Norum KR. The Oslo Study. Cardiovascular disease in middle-aged and young Oslo men. Acta Med Scand 1975; (Suppl.588): 1-38.
- Hjermann I, Velve KB, Holme I, Leren P. Effect of diet and smoking intervention on the incidence of coronary heart disease. A randomized trial in healthy men. The Oslo Study. Lancet 1981; ii: 1303-10.
- Helgeland A. Treatment of mild hypertension: A five year controlled drug trial. The Oslo Study. Am J Med 1980; 69: 725-32.
- Holme I, Helgeland A, Hjermann I, Leren P, Lund-Larsen PG. Four year mortality by some socioeconomic indicators: The Oslo Study. J Epidemiol Community Health 1980; 34: 48-52.
- Lund Håheim L, Holme I, Hjermann I, Leren P. Risk factors of stroke and mortality. A 12-year follow-up of the Oslo Study. Stroke 1993;24:1484-9.
- Lund-Larsen PG. ECG in Health and Disease. ECG findings in relation to CHD risk factors, constitutional variables and 16-year mortality in 2990 asymptomatic Oslo men aged 40-69 years in 1972. The Oslo Study. Thesis. ISM skriftserie nr 30, Tromsø, Norway: University of Troms 1994.
- Holme I, Lund Håheim, Lise. Prediksjonsfunksjoner for 21 års utvikling av hjerteinfarkt fra Oslo-undersøkelsen 1972/73. Tidsskr Nor Lægeforen 2003;123:1050-3.
- Lund Håheim L, Holme I, Hjermann I, Leren P, Tonstad S.Trends in the incidence of acute myocardial infarction and stroke: a 21-year follow-up of the Oslo study. Scand Cardiovasc J. 2004;38:216-21.
- Lund Håheim L, Holme I, Hjermann I, Leren P, Tonstad S. Comparative analyses of risk factor profile for the incidence of subarachnoid and intracerebral haemorrhage, cerebral infarction and unspecified stroke during 21-years’ follow-up in men. Scan J Public Health Online. 27/6/2006. Scand J Public Health. 2006;34:589-97.
- Lund Håheim L, Nafstad P, Wisløff TF, Holme I, Hjermann I, Leren P. Metabolic syndrome predicts prostate cancer in a cohort of middle aged men followed for 26 years. Am J Epidemiol 2006;164:769-774.
- Lund Håheim L, Tonstad S, Hjermann I, Leren P, Holme I. Predictivity of body mass index and other risk factors for fatal coronary heart disease: a 21-year prospective cohort study. Scan J Public Health, 2007;35:1-10.
Second round of the Oslo Study - Oslo II
The second round of the Oslo-study was conducted in 2000, and was a follow-up screening of The Oslo Study in 1972/73
Participants in 2000
The data collection was conducted during the spring of 2000 in co-ordination with and prior to the Oslo Health Study (HUBRO). All men previously invited to the Oslo Study in 1972/73 and who were residents in Oslo and Akershus were invited to the screening in 2000. Men who would be invited to the later HUBRO and MoRostudies in 2000 were not invited, but their data were later added to the Oslo Study-datafile. (MoRo was a survey in parts of Oslo (Romsås and Furuset) and acted as baseline for a community-based intervention project aimed at promoting physical activity and preventing obesity, diabetes and CHD. The intervention was evaluated with a new survey in 2003).
Neither were persons who already participated in three CHD-prevention projects at Ullevål University Hospital invited, but they were later sent the questionnaires by mail. Data on blood pressure, weight and height from these three studies as well as results from the lipid analyses from these men, were later linked to the Oslo Study-datafile.
Of men who met to the Oslo Study in 1972/73, 7 157 participated in the second round of the Oslo-study in 2000.
Questionnaires, data collection and feedback
The letter of invitation including two questionnaires, a 4-page main questionnaire and a 2-page supplementary questionnaire, was mailed two weeks prior to the appointment. The letter included information on how and where the clinical examination should take place. Both questionnaires were made in two versions, depending on the age of the participants. The main questionnaire was the same as the main questionnaire used in HUBRO and the version for those less than 68 years is translated into Hovedskjema engelsk HUBRO (pdf).
The place of appointment was in the central east part of Oslo, as for the HUBRO-study.
The questionnaires were handed in there. All participants signed a letter of consent. Blood-samples were stored for research purposes.
About two weeks after the examination the participants got a feedback-letter by post. The letter informed about the attendants height, weight, body mass index, blood pressure, total serum cholesterol, HDL-cholesterol, triglycerides and glucose. The letter also contained information about the importance of different risk factors. Persons with a high risk of cardiovascular disease and diabetes were recommended to further control with their local doctor.
The results show considerable changes in risk factors for CHD during the 28 years between the two studies. The variation may be due to changes in lifestyle, use of medication and/or natural ageing. A substantial decline in the percentage daily smokers was registered. The study showed an increase in weight and body mass index in all age groups examined. The changes were more pronounced in the younger compared to the older age groups.
Several sub-projects are in progress and the results will be published continuously.
Publications from the Oslo II study:
- Holme I, Søgaard AJ, Lund-Larsen PG, Tonstad S, Lund Håheim L: Lønner det seg å leve sunt? Tidsskr Nor Lægeforen 2006; 126: 2246-9.
- Holme I, Tonstad S, Søgaard AJ, Lund-Larsen PG, Lund Håheim L: Leisure time physical activity in middle age predicts the metabolic syndrome in old age: results of a 28-year follow-up by men in the Oslo study. BMC Public Health 2007, 7:154.
- Holme I, Søgaard AJ, Håheim LL, Lund-Larsen P, Tonstad S: Repeated weight loss is associated with the metabolic syndrome and diabetes: Results of a 28 year re-screening of men in the Oslo Study. Metabolic Syndrom Rel Disord 2007: 5; 127-135.
- Håheim LL, Holme I, Søgaard AJ, Lund-Larsen PG: Endring i risikofaktorer for hjerte- og karsykdom blant menn i Oslo gjennom 28 år. Tidsskr Nor Lægeforen 2006; 126: 2240-5.
- Håheim LL, Lund-Larsen PG, Søgaard AJ, Holme I. Risk factors associated with body mass index increase in men at 28 years follow-up. QJM. 2006; 99: 665-71. Også publisert i QJM`s South African Excerpts Edition 2006; 5: 225-31.
- Håheim LL, Olsen I, Nafstad P, Schwarze P, Rønningen KS: Antibody levels to single bacteria or in combination evaluated against myocardial infarction. J Clin Periodontol 2008; 35: 473-8.
- Håheim LL, Olsen I,Nafstad P, Schwarze P, Rønningen KS: Antibody levels to single bacteria or in combination evaluated against myocardial infarction. J Clin Periodontol 2008; 35: 473-478.
- Håheim LL, Olsen I,Nafstad P, Schwarze P, Rønningen KS: Ikke enkeltbakterier, men et knippe av bakterier øker risikoen for myokardinfarkt. Nor Tannlegeforen 2008; 10: 664.
- Håheim LL, Olsen I,Nafstad P, Schwarze P, Rønningen KS: C-reactive protein variations for different chronic somatic disorders. Sc J Publ Health. 2009 Apr 16. (Epub ahead of print).
- Håheim LL: Changes in research focus with time. The Oslo-study of 1972/73 and until today. Chapter; Heart Disease in Men. Nova Science Publishers, Inc. NY, USA. 2009.
- Håheim LL, Olsen I,Nafstad P, Schwarze P, Rønningen KS: C-reaktivt protein (CRP) varierer ved forskjellige kroniske lidelser. Nor Tannlegeforen Tid 2010; 120: 46.
- Jenum AK, Graff-Iversen S, Selmer RM, Søgaard AJ: Risikofaktorer for hjerte- og karsykdom og diabetes gjennom 30 år. Tidskr Nor Lægeforen 2007;19: 2532-6.
- Madsen C, Nafstad P, Eikvar L, Schwarze PE, Rønningen KS, Haaheim LL: Association between tobacco smoke exposure and levels of C-reactive protein in the Oslo II Study. Eur J Epidemiol 2007; 22: 311-7.
- Madsen C, Durand KL, Nafstad P, Schwarze PE, Rønningen KS, Haheim LL: Associations between environmental exposures and serum concentrations of Clara cell protein among elderly men in Oslo, Norway 2008; 108: 354-60.
- Søgaard AJ, Eie T, Håheim LL. Oslo-undersøkelsen (Oslo I - Oslo II). Folkehelseinstituttet, september 2005.
- Søgaard AJ, Eie T, Håheim LL. The Oslo Study I and II. Norwegian Institute of Public Health, September 2005.
- Søgaard AJ, Dalgard OS, Holme I, Røysamb E, Håheim LL. Associations between type A behaviour pattern and psychological distress: 28 years of follow-up of the Oslo Study 1972/1973. Soc Psychiatry Psychiatr Epidemiol 2008; 43: 216-23.
- Søgaard AJ, Meyer HE, Tonstad S. Haheim LL, Holme I.Weight cycling and risk of forearm fractures: A 28-year follow-up of men in the Oslo Study. American Journal of Epidemiology 2008; 167: 1005-13.
List of abstracts:
- Håheim LL, Leren P, Hjermann I, Lund-Larsen PG, Holme I, Haugstvedt Y, Ånstad U, Søgaard AJ: The Oslo Study after 28 years. Changes in risk factors for cardiovascular disease between the first and second screening in 1972/73 and 2000. 2nd Nordic Conference in Epidemiology, Aarhus, June 2002.
- Håheim LL, Leren P, Hjermann I, Holme I, Lund-Larsen PG, Haugstvedt Y, Ånstad U, Søgaard AJ: Endring i relativ vekt etter alder. Nor Epidemiol 2002; 12 (Suppl. 1): 21.
- Håheim LL, Leren P, Hjermann I, Holme I, Lund-Larsen PG, Haugstvedt Y, Ånstad U, Søgaard AJ: Gjør tannverk mer enn vondt? Nor Epidemiol 2002; 12 (Suppl 1): 24.
- Håheim LL, Lundby L, Olsen I, Dahlmann HJ, Nafstad P, Schwarze P, Magnus P, Rønningen KS: Assosiasjon mellom antistoffer for fire orale bakterier og hjerteinfarkt. Foredrag.Norsk forening for epidemiologi, konferanse, Tromsø 2005.
- Håheim LL, Lundby L, Olsen I, Dahlmann HJ, Nafstad P, Schwarze P, Magnus P, Rønningen KS: Sammenlikning av C-reaktivt proteins assosiasjon til infeksjoner og andre sykdommer. Poster. Norsk forening for epidemiologi, konferanse, Tromsø 2005.
- Håheim LL, Olsen I,Nafstad P, Schwarze P, Rønningen KS: Comparison of C-reactive protein levels for cardiovascular disease and a number of chronic disorders. Poster. World Congress on Cardiology (WCC), Barcelona, 2006.
- Håheim LL, Olsen I,Nafstad P, Schwarze P, Rønningen KS: Antibodies of bacteria and CRP confer risk for myocardial infarction. Poster. American Heart Scientific Sessions, Chicago. 2006.
- Olsen I,Nafstad P, Schwarze P, Rønningen KS, Håheim LL: Tooth extractions, bacterial antibodies and C-reactive protein in relation to myocardial infarction. IADR, New Orleans. 2007.
- Søgaard AJ, Meyer HE, Dalgard OS, Holme I, Håheim LL: Er det sammenheng mellom psykologisk distress og underarmsbrudd? Osloundersøkelsene 1972/73 og 2000. Abstrakt NOFE-konferanse, Bergen. 2008.
List of student projects and doctorate theses based on the Oslo II-study
- Christian Madsen: Urban environmental exposures and potential markers of risk for cardiovascular disease. Thesis, PhD, Faculty of Medicine, University of Oslo, 2009.