DOHK is the acronym for the Swedish Diabetes och Hjärta-Kärl.
Patients diagnosed with diabetes have an increased risk to develop cardiovascular complications such as acute myocardial infarction (AMI) and stroke. Up to today, about 30 different genes have been identified as predisposing for type 1 diabetes. Furthermore, about 60 different genes have shown associations to cardiovascular disease. Some of these genes are related to dyslipidemia while others are associated to AMI. We believe that certain combinations of diabetes risk genes and genes associated to cardiovascular disease can precipitate cardiovascular disease at an earlier age in patients with diabetes compared with controls.
The aim of this study is to identify risk factors that predict cardiovascular disease in patients with diabetes and also to assess all-cause mortality in this cohort.
The cohort of patients and controls in this study were first identified in 1992 and 1993. In 1992 and 1993 a total of 879 patients were diagnosed with diabetes in the ages of 15-34 years in Sweden. We have full information about clinical classification together with blood samples from 764 patients. These patients were followed with annual blood samples for the first six years of disease. A total of 837 healthy controls matched for age and sex also donated a blood sample close to onset of diabetes of the index case.
In March 2007, we obtained current addresses from the Swedish Population and Address Register (SPAR). Existing records showed that 94% (824/879) of the patients were alive and had an address in Sweden. Likewise, 95% (792/837) of the controls were alive and had an address in Sweden. We obtained informed consent for this study from 63% (505/791) and from 72% (567/792) from the healthy controls. This study has been approved by the Regional Ethical committee, Lund, Sweden.
We linked records from the Swedish Cause of Death Register and the In Patient Care Register maintained by the National Board of Health and Welfare, Stockholm, Sweden to our biochemical and genetic data. There are a number of known biochemical risk factors for cardiovascular disease such as ApoA1 and ApoB1, CRP, creatinine and cystatin C. These biochemical risk factors have been analysed at the Department of Clinical Chemistry, University Hospital MAS, Malmö, Sweden. Tentative genetic risk markers for cardiovascular disease are analysed at the Competence Centre for Clinical Research, University Hospital MAS, Malmö, Sweden. The genetic risk factors for type 1 diabetes are analysed at Karolinska Institute, Solna, Sweden.
At present we are working with statistical evaluation and interpretation of the data from records and results from biochemical markers.
The DOHK study is supported by grant from The Crafoord Foundation, Lund, Sweden.