Data Needs for Cardiovascular Events, Management, and Outcomes
The Finnish Experience With a National CVD Event Register
During 1991-2003 -
Dr. Veikko Salomaa
There are two types of population-based cardiovascular disease registers
in Finland. The FINAMI register (1,2) is based on detailed reviewing of
hospital documents, death certificates and autopsy reports following the
tradition of the WHO MONICA Project. It is operating in four geographical
areas of Finland and aims to register every CHD event in monitored populations.
The register is planned for scientific research and has standardized data
collection and quality control procedures. Therefore, the data it produces
can be considered as accurate and reliable. The limitation is that the
register is rather laborious and expensive to maintain and can cover only
a small fraction of the country. The other type of CVD register is based
on record linkage of administrative data, i.e., the National Hospital
Discharge Register and the National Causes-of-Death Register (3,4). These
country-wide computerized registers cover every hospitalisation in Finland
and all deaths of permanent residents of the country. They can be linked
together on the basis of the personal ID code, unique to every resident
of Finland. Data on CHD and stroke events during 1991-2003 based on the
record linkage of these administrative registers have been placed in the
Internet, where they are freely available (also in English) at http://www.ktl.fi/cvdr/
. The database has a user-friendly interface, which allows easy examination
of event rates, in-hospital and out-of-hospital case fatality as well
as one-year prognosis by age, sex, and hospital district. The strength
of the administrative registers is that they cover the whole country and
all age groups and provide data on large numbers of CVD events at a modest
cost. For example, our database for the period 1991-2003 includes 333
015 CHD and 304 863 stroke events. On the other hand, only a limited standardization
and quality control are possible for the administrative data. However,
the more detailed FINAMI register can be used as a validation instrument
for the country-wide administrative CVD-register. Validation studies have
shown that the sensitivity and positive predictive value of CVD diagnoses
in the Finnish administrative registers are reasonably good (5). Similar
national CVD registers based on administrative data exist also in Sweden
and Denmark. In the framework of the NORDAMI Project we are currently
establishing common definitions for CVD events in these registers. The
goal is that in the near future reasonably comparable data on the incidence
and case fatality of CVD events in these three Nordic countries become
freely available at a common website. At the European Union level, the
EUROCISS (=European Cardiovascular Indicators Surveillance Set) Project
aims to identify a set of CVD indicators, for which monitoring is both
needed and feasible in the whole EU (6).
Figure 1 demonstrates the trends in the incidence of first ever MI events
in Finland during 1991-2003, based on the administrative data. The decline
was steep until 1997 and somewhat slower after that, which is likely to
be due to the widespread adoption of troponins as the markers of myocardial
injury. We have analyzed the effects of changing diagnostic criteria on
the event rate estimates of MI using data from the FINAMI register (2).
The findings suggested that the estimates of hospitalised CHD events increased
by 15% among men and 38% among women aged 35-74 years with the adoption
of troponins and the latest diagnostic criteria (7). Somewhat surprisingly,
the additional cases identified by troponins and the new criteria had
worse prognosis than those cases, which were definite MIs also according
to the WHO MONICA criteria based on enzymatic markers of myocardial injury.
In conclusion, a country-wide CVD register based on administrative data
and a geographically limited but more rigorously standardized register
are used in a complementary manner in Finland. Together they provide a
fairly good picture on the occurrence, case fatality and prognosis of
CVD events in the country.
Figure 1. The age-standardized incidence of first MI events
in 1991-2003 in Finland. The annual average decline was 4.9% (95%
CI -5.2% to -4.5%) from 1991 to 1997 and 2.1% (95% CI -2.5% to -1.8%)
from 1998 to 2003 among men. The respective changes among women were
-5.2% (95% CI -5.8% to -4.7%) and -2.1% (95%CI -2.7% to -1.5%).
- Salomaa V, Ketonen M, Koukkunen H, Immonen-Räihä P, Jerkkola
T, Kärjä-Koskenkari P, Mähönen M, Niemelä M,
Kuulasmaa K, Palomäki P, Mustonen J, Arstila M, Vuorenmaa T, Lehtonen
A, Lehto S, Miettinen H, Torppa J, Tuomilehto J, Kesäniemi YA,
Pyöralä K. Decline in out-of-hospital coronary heart disease
deaths has contributed the main part to the overall decline in coronary
heart disease mortality rates among persons 35 to 64 years of age in
Finland: the FINAMI study. Circulation 2003;108:691-696.
- Salomaa V, Koukkunen H, Ketonen M, Immonen-Räihä P, Kärjä-Koskenkari
P, Mustonen J, Lehto S, Torppa J, Lehtonen A, Tuomilehto J, Kesäniemi
A, Pyörälä K, for the FINAMI Study Group. A New Definition
for Myocardial Infarction - What Difference Does it Make?, Eur Heart
J, in press, doi:10.1093/eurheartj/ehi185.
- Pajunen P, Pääkkönen R, Hämäläinen
H, Keskimäki I, Laatikainen T, Niemi M, Rintanen H, Salomaa V.
Trends in fatal and non-fatal strokes among persons aged 35-85+ years
during 1991-2002 in Finland. Stroke 2005;36:244-248.
- Pajunen P, Pääkkönen R, Juolevi A, Hämäläinen
H, Keskimäki I, Laatikainen T. Moltchanov V, Niemi M, Rintanen
H, Salomaa V. Trends in fatal and non-fatal coronary heart disease events
in Finland during 1991-2001. Scand Cardiovasc J 2004;38:340-344.
- Pajunen P, Koukkunen H, Ketonen M, Jerkkola T, Immonen-Räihä
P, Kärjä-Koskenkari P, Mähönen M, Niemelä M,
Kuulasmaa K, Palomäki P, Mustonen J, Lehtonen A, Arstila M, Vuorenmaa
T, Lehto S, Miettinen H, Torppa J, Tuomilehto J, Kesäniemi YA,
Pyörälä K, Salomaa V. The validity of the Finnish Hospital
Discharge Register and Causes of Death Register data on coronary heart
Disease. Eur J Cardiovasc Prev and Rehabilit 2005;12:132-137.
- The EUROCISS Working Group. Coronary and cerebrovascular registers
in Europe: Are morbidity indicators comparable? Results from the EUROCISS
Project. Eur J Publ Health 2003;13(suppl 3):55-60.
- Luepker RV, Apple FS, Christenson RH, Crow RS, Fortman SP, Goff D,
Goldberg RJ, Hand MM, Jaffe AS, Julian DG, Levy D, Manolio T, Mendis
S, Mensah G, Pajak A, Prineas RJ, Reddy KS, Roger VL, Rosamond WD, Shahar
E, Sharrett AR, Sorlie P, Tunstall-Pedoe H. Case definitions for acute
coronary heart disease in epidemiology and clinical research studies:
a statement from the AHA Council on Epidemiology and Prevention; AHA
Statistics Committee; World Heart Federation Council on Epidemiology
and Prevention; the European Society of Cardiology Working Group on
Epidemiology and Prevention; Centers for Disease Control and Prevention;
and the National Heart Blood and Lung Institute. Circulation 2003;108:311-319.
Back to Workshop Agenda