Increasing Prevalence Despite Decreasing Incidence of Ischemic Heart Disease and Myocardial Infarction A National Register Based Perspective in Denmark, 1980-2009. M.B. Koch, M. Davidsen, L.V. Andersen , K. Juel & G.B. Jensen. Figure 1a INCIDENCE of IHD and AMI
Increasing Prevalence Despite Decreasing Incidence of Ischemic Heart Disease and Myocardial Infarction
A National Register Based Perspective in Denmark, 1980-2009
M.B. Koch, M. Davidsen, L.V. Andersen, K. Juel & G.B. Jensen
Figure 1aINCIDENCE of IHD and AMI
from 2000 to 2009 . Age 35+
Figure 1bPREVALENCE of IHD and AMI from 2000 to 2009 . Age 35+
MATERIAL AND METHOD
Changes in incidence and prevalence from 2000 to 2009 are presented using nationwide data from The Danish Register of Causes of Death  and The Danish National Patient Register .
An incident case is defined as a subject (age 35+) registered with a diagnosis of IHD/AMI and without a prior diagnosis for the past 20 years (beginning in 1979). A prevalent case is defined as a subject (age 35+) surviving the first year after the incident diagnosis.
Mortality from Ischemic Heart Disease (IHD) including Acute Myocardial Infarction (AMI) in Denmark peaked around 1977. A marked decline has occurred since [1,2].
The decline in mortality is caused by decreasing incidenceand increasing effect of treatment. The effect of these changes on the prevalence, the number of cases living with IHD, is not precisely known. Therefore, we have studied the influence of changes in incidence and demographic developments on prevalence rates and numbers.
Age-standardised rates pr. 100,000
Table 1Prevalence of IHD from 2000 to 2009. Number of persons
Regarding IHD, age-standardised incidence rates (per 100,000) declined significantly from 2000 to 2009 for both sexes (females 445 to 340, males 822 to 678). This Reflects a reduction in the annual number of new cases from 19,345 to 16,757.
Despite the reduction in incidence, prevalence rates (per 100,000) increased slightly (females 2,389 to 2,616 males 5,447 to 5,579). Due to a demographic development resulting in increased proportion of elderly subjects, the total number of prevalent cases increased from about 124,000 in 2000 to 147,000 in 2009. About 3 % of the Danish population (5.5 million subjects) is afflicted by IHD. A similar development occurred for AMI albeit with lower numbers. Number of subjects having survived an AMI increased from about 67,000 to 72,000.
Figure 2aPREVALENCE of IHDin 2000 and 2009.
Figure 2bPREVALENCE of survivors afterAMI in 2000 and 2009.
Rates pr. 100,000
Figure 3aPREVALENCE of IHDin 2000 and 2009. Number of persons.
Figure 3bPREVALENCE of survivors afterAMI in 2000 and 2009. No. of persons.
The use of valid long-term national registers makes the determination of precise incidence and prevalence data possible. Decreasing incidence, reduced case fatality and demographic development results in an increased prevalence of IHD.
The decline in incidence is more than offset by a larger decline in case fatality. Consequently, prevalence continues to increase. The epidemic of Ischemic Heart Disease is far from over, in spite of marked success of prevention and treatment.
1. Osler M, Sørensen TI, Sørensen S, Rostgaard K, Jensen G, Iversen L, Kristensen TS, Madsen M. Trends in mortality, incidence and case fatality of ischaemic heart disease in Denmark, 1982-1992. Int J Epidemiol. 1996;6:1154-61.
2. Schmidt M, Jacobsen JB, Lash TL, Bøtker HE, Sørensen HT. 25 year trend in first time hospitalisation for acute myocardial infarction, subsequent short and long term mortality, and the prognostic impact of sex and comorbidity: a Danish nationwide cohort study. BMJ 2012;344:e356doi:10.1136/bmj.e356
3. Helweg-Larsen K. The Danish Register of Causes of Death. Scandinavian Journal of Public Health, 2011; 39 (Suppl 7):39:26-29.
4. Lynge E, Sandegaard JL, Rebolj M. The Danish National Patient Register. Scandinavian Journal of Public Health, 2011; 39 (Suppl 7): 30-33.
Number of persons
Contact: Lisbeth Vestergaard Andersen: [email protected]