Læknablaðið - 15.01.1993, Blaðsíða 33

LÆKNABLAÐIÐ
27
sem kransæðakölkun hefur verið löðuð fram
með fóðri ríku af mettaðri fitu hefur verið
unnt að draga úr framvindu æðakölkunar með
því að hægja á hjartslætti (13). Hugsanlegt er
að flæðiaðstæður verði hagstæðari við hægari
hjartslátt þannig að ágangur blóðflæðis á
æðaþel og æðavegg minnki og þannig dragi
úr æðaþelsáverka og framvindu æðakölkunar.
Beint samband er milli hjartsláttartíðni
og súrefnisþarfar hjartavöðvans. í þeim
sem þegar hafa kransæðasjúkdóm er því
styttra í blóðþurrð (myocardial ischemiu)
og afleiðingar hennar, því hraðari sem
hjartslátturinn er. I sama sjúklingahópi getur
hraður hjartsláttur verið vísbending um lélegt
ástand hjartavöðvans og af þeirri ástæðu spáð
fyrir um lakari horfur en þegar hjartsláttur er
hægari.
Hugsanlegt er að allir ofangreindir þættir
eigi hlut að máli. Fylgni hjartsláttartíðni
við sökk og þéttni blóðrauða sem og við
heildardánartíðni, samband sem bæði í okkar
rannsókn og öðrum er jafnvel sterkara en við
dánartíðni úr kransæðasjúkdómi, bendir til að
málið kunni að vera jafnvel enn flóknara.
SUMMARY
In the third stage of the »Health survey in the
Reykjavik area« 1974-’76 resting heart rate was
recorded under standardized conditions in 5565
males aged 41-68 years, a representative sample of
men in that age range living in the Reykjavik area.
The correlation to other known risk factors was
estimated by the T-test and stepwise multiple
regression.
The independent effect of heart rate as a risk factor
for cardiovascular and some other diseases was
estimated using Cox’s proportional hazard model.
Heart rate was positively correlated to body
mass index, skinfold thickness, serum total
cholesterol, serum triglycerides, fasting blood
glucose, hemoglobine, hematocrit and ESR but
most strongly to systolic and diastolic blood
pressure.
In this study resting heart rate was found to be
an independent and significant risk factor for total
mortality in the whole cohort, an increase in mean
heart rate by one beat a minute increasing the risk
by about 1%.
In cigarette-smokers heart rate was also a strong
risk factor for coronary heart disease death (CHD),
an increase in mean heart rate increasing the risk
by about 2%. In ex-smokers and non-smokers heart
rate was not a risk factor for CHD. Heart rate was
not a significant risk factor for cerebrovascular
disease irrespective of smoking habits.
HEIMILDIR
1. Kannel WB, Kannel C, Paffenbarger RS, Cupples
LA. Heart rate and cardiovascular mortality: The
Framingham Study. Am Heart J 1987; 113: 1489-94.
2. Gillum RF. The epidemiology of resting heart rate in
a national sample of men and women: Associations
with hypertension, coronary heart disease, blood
pressure and other cardiovascular risk factors. Am
Heart J, 1988; 116: 163-74.
3. Dyer AR, Persky V, Stamler J, et al. Heart rate as
a prognostic factor for coronary heart disease and
mortality: Findings in three Chicago epidemiological
studies. Am J Epidemiol 1980; 112: 736-49.
4. Bjömsson OJ, Davidsson D, Ólafsson H, Ólafsson
Ó, Sigfússon N, Thorsteinsson Th. Health Survey in
the Reykjavík Area. - Men. Stages I-III, 1967-1968,
1970-1971 and 1974-1976. Participants, invitation,
response etc. Report ABC XVIII. Reykjavik: Heart
Preventive Clinic, 1979.
5. Sigfusson N. Hypertension in middle-aged men.
The effect of repeated screening and referral to
community physicians on hypertension control. Acta
Med Scand 1986; Suppl. 710: 1-131.
6. Bjömsson OJ, Davíðsson D, Ólafsson Ó, Sigfússon
N, Þorsteinsson Þ. Survey of Semm Lipid Levels in
Icelandic Men Aged 34-61 Years. An epidemiological
and statistical evaluation. Acta Med Scand 1977;
Suppl. 616: 1-150.
7. Bjömsson OJ, Davídsson D, Filippusson H, Ólafsson
Ó, Sigfússon N, Thorsteinsson Th. Distribution of
Haematological, Semm and Urine Values in a General
Population of Middle-aged Men. The Reykjavík
Study. Scand J Soc Med 1984; Suppl. 32: 1-12.
8. Sigurdsson G, Gottskálksson G, Thorsteinsson Th, et
al. Community Screening for Glucose Intolerance
in Middle-Aged Icelandic Men. Deterioration to
Diabetes over a Period of l'h Years. Acta Med Scand
1981; 210: 21-6.
9. Havlik RJ, Garrison RJ, Fabsitz R, Feinleib M.
Variability of Heart Rate, P-R, QRS and Q-T
Durations in Twins. J Electrocardiol 1980; 13(1): 45-
8.
10. Dixon WJ, Brown MB, Engelman L, et al. BMDP
Statistical Software Manual. Berkeley: University of
Califomia Press, 1985.
11. Cox DR. Regression models and life tables. J Stat
Soc 1972; 34 (Series B): 187-220.
12. Grimby G, Saltin B. Physiological analysis of
physically well trained middle-aged and old athletes.
Acta Med Scand, 1966; 179: 513-26.
13. Marks RG, Hale WE, Moore MT, May FE, Stewart
RB. Resting Heart Rates in an Ambulatory Elderly
Population: An Evaluation of Age, Sex, Symptoms
and Medication. Gerontology 1989; 35: 210-7.
14. Beere PA, Glasov S, Zarius CK. Retarding effect
of lowered heart rate on coronary atherosclerosis.
Science 1984; 266: 180-2.