Is exposure to low doses of radiation a new risk factor of circulatory disease? Low doses of radiation old problem, new challenge
Possibility of development of cardiovascular disease is well known as
consequence of high exposure to radiation , however in relation to low
doses data are not convicting (1,2,3,4,5,6). Shimizu et al. analyzed 81
611 atomic bomb survivors between 1950 – 2003 in relation to risk of heart
disease and stroke after exposure from 0 to more than 3 Gy (86% received
<0.2 Gy). The dose in range 0.5 – 3 Gy suggested an excess risk of
cardiovascular diseases, but doses from 0 to 0.5 were not significant.
We studied occupational exposure of X – ray department workers to low
doses of ionizing radiation in Katowice, southern Poland, especially if
occupational exposure to radiation is associated with induction of
inflammation and is a risk of cardiovascular disease. Serum concentration
of C reactive protein (CRP), interleukin - 1beta (IL -1 beta), tumor
necrosis factor - alfa, (TNF-alfa), interleukin – 6 (IL - 6)
(proinflammatory cytokines) showed only slightly higher increase in X –
ray department workers compared with control group (7,8,9,10). It
suggested that occupational exposure to radiation is not associated with
inflammation and risk of cardiovascular disease. However, atomic bomb
survivors also did not reveal changes in concentration of TNF-alfa in
four radiation dose groups: nonexposed, low dose (0.005 to 0.7 Gy), medium
dose (0.7 to 1.5 Gy) and high dose (>1.5 Gy)(11) but CRP concentrations
were not measured in this group. CRP is independent risk factor of heart
disease or stroke and increases in obesity, dyslipidemia, diabetes and
hypertension affecting atherosclerosis as chronic, inflammatory process
with part of immune system and significant role for TNF-alfa , IL -1beta
and IL-6 (12,13).
The Japanese authors included subgroup of 36 468 survivors with analysis
for sociodemographic factors (education, occupation), lifestyle factors
(smoking, alcohol intake) as well as health variables (obesity, diabetes)
and showed a little effect on risk for any end point. We agree with
opinion of Mark P. Little, who suggested in letter to Editorials that
Japanese authors did not present data about other well known risk factors
for cardiovascular diseases, such dislipidemia (type), hypertension and
level of these disturbances as well as physical activity (14).
On the other hand, we studied activity of antioxidant erythrocyte enzymes
in X – ray department workers . Low activity was demonstrated compared
with control group, which suggested decreased antioxidant defense and
possible damage or functional changes of endothelium (1, 15).
We would like to emphasize value of the publication due to the analysis
of large group and indicate the possible link between cardiovascular
diseases and ionizing radiation. Influence of low doses of radiation on
public health seems to be important because recently reported increased
medical imaging procedures with the higher radiation exposure in some
patients compared with the staff of radiology clinics and nuclear
companies (16). Fazel et al. demonstrated that more than 30%of men and 40%
of women under age of 50 years received doses exceeding 20 mSv/year,
whereas in workers of health care and the nuclear industry cumulative
effective doses are restricted to 100 mSv ever 5 years (mean 20 mSv per
year) with maximal exposure of 50 mSv allowed in any given year. We
concluded, that the increasing exposure to low dose of radiation requires
new studies to explain association between such exposure and possible
development of cardiovascular diseases with monitoring of risk factors,
cumulative effective dose and inflammatory parameters.
1. Schultz-Hector S, Trott KR. Radiation-induced cardiovascular
diseases: is the epidemiologic evidence compatible with the radiobiologic
data? Int J Radiat Oncol Biol Phys 2007;67:10-8.
2. Hauptmann M, Mohan AK, Doody MM, Linet MS, Mabuchi K. Mortality from
diseases of the circulatory system in radiologic technologists in the
United States. Am J Epidemiol 2003;157:239-48.
3. Vrijheid M, Cardis E, Ashmore P, Auvinen A, Bae JM, Engels H, et al.
Mortality from diseases other than cancer following low doses of ionizing
radiation: results from the 15-Country Study of nuclear industry workers.
Int J Epidemiol 2007;36:1126-35.
4. Kreuzer M, Kreisheimer M, Kandel M, Schnelzer M, Tschense A, Grosche
B. Mortality from cardiovascular diseases in the German uranium miners
cohort study, 1946-1998. Radiat Environ Biophys 2006;45:159-66.
5. Muirhead CR, O’Hagan JA, Haylock RG, Phillipson MA, Willcock T,
Berridge GL, et al. Mortality and cancer incidence following occupational
radiation exposure: third analysis of the national registry for radiation
workers. Br J Cancer 2009;100:206-12.
6. Shimizu Y, Kodama K, Nishi N, Kasagi F, Suyama A, Soda M et al.
Radiation exposure and circulatory disease risk: Hiroshima and Nagasaki
atomic bomb survivor data, 1950-2003. BMJ 2010;340:b5349.
7. Hrycek A, Czernecka-Miciñska A, K³uciñski P, Badowski R. Peripheral
blood lymphocytes and selected serum interleukins in workers operating X-
ray equipment. Toxicol Lett 2002 ;132:101-17.
8. K³uciñski P, Mazur B, Kaufman J, Hrycek A, Cieœlik P, Martirosian G.
Assessment of blood serum immunoglobulin and C-reactive protein
concentrations in workers of x-ray diagnostics units. Int J Occup Med
Environ Health 2005;18:327-30.
9. K³uciñski P, Mazur B, Wiechu³a B, Maœluch E, Kaufman J, Hrycek A et al.
. Evaluation of cellular isoform of prion protein expression on the
surface peripheral blood monocytes and serum concentrations of interleukin
1β and interleukin 1β receptor antagonist in workers operating X
-ray equipment. Diagn Lab 2006; 42: 369-74.
10. K³uciñski P, Maœluch E, Wiechu³a B, Hrycek A, Mazur B, Kaufman J et
al. Serum concentrations of tumor necrosis factor α and its soluble
receptors TNFR1 and TNFR2 in workers of X-ray departments. Ann Acad Med
Siles 2006; 60: 308-11
11. Hayashi T, Morishita Y, Kubo Y, Kusunoki Y, Hayashi I, Kasagi F et al.
Long-term effects of radiation dose on inflammatory markers in atomic bomb
survivors. Am J Med 2005;118:83-6.
12. Ridker PM, Buring JE, Cook NR, Rifai N. C-reactive protein, the
metabolic syndrome, and risk of incident cardiovascular events: an 8-year
follow-up of 14 719 initially healthy American women. Circulation
2003;107:391-97.
13. de Winther MP, Kanters E, Kraal G, Hofker MH. Nuclear factor kappaB
signaling in atherogenesis. Arterioscler Thromb Vasc Biol 2005;25:904-14.
14. Little MP. Exposure to radiation and higher risk of circulatory
disease. BMJ 2010; 340: b4326-b4326
15. K³ucinski P, Wójcik A, Grabowska-Bochenek R, Gmiñski J, Mazur B,
Hrycek A et al. Erythrocyte antioxidant parameters in workers
occupationally exposed to low levels of ionizing radiation. Ann Agric
Environ Med 2008;15:9-12.
16. Fazel R, Krumholz HM, Wang Y, Ross JS, Chen J, Ting HH et al. Exposure
to low-dose ionizing radiation from medical imaging procedures. N Engl J
Med 2009;361:849-57.
Competing interests:
None declared
Competing interests:
No competing interests
04 February 2010
Piotr K³uciñski
associated professor
Gayane Martirosian professor, head of Department of Medical Micriobiology, Medical University of Silesia, 40-752 Katowice, Poland
Department of Medical Micobiology, Medical University of Silesia, 40-0752 Katowice, Poland
Rapid Response:
Is exposure to low doses of radiation a new risk factor of circulatory disease? Low doses of radiation old problem, new challenge
Possibility of development of cardiovascular disease is well known as
consequence of high exposure to radiation , however in relation to low
doses data are not convicting (1,2,3,4,5,6). Shimizu et al. analyzed 81
611 atomic bomb survivors between 1950 – 2003 in relation to risk of heart
disease and stroke after exposure from 0 to more than 3 Gy (86% received
<0.2 Gy). The dose in range 0.5 – 3 Gy suggested an excess risk of
cardiovascular diseases, but doses from 0 to 0.5 were not significant.
We studied occupational exposure of X – ray department workers to low
doses of ionizing radiation in Katowice, southern Poland, especially if
occupational exposure to radiation is associated with induction of
inflammation and is a risk of cardiovascular disease. Serum concentration
of C reactive protein (CRP), interleukin - 1beta (IL -1 beta), tumor
necrosis factor - alfa, (TNF-alfa), interleukin – 6 (IL - 6)
(proinflammatory cytokines) showed only slightly higher increase in X –
ray department workers compared with control group (7,8,9,10). It
suggested that occupational exposure to radiation is not associated with
inflammation and risk of cardiovascular disease. However, atomic bomb
survivors also did not reveal changes in concentration of TNF-alfa in
four radiation dose groups: nonexposed, low dose (0.005 to 0.7 Gy), medium
dose (0.7 to 1.5 Gy) and high dose (>1.5 Gy)(11) but CRP concentrations
were not measured in this group. CRP is independent risk factor of heart
disease or stroke and increases in obesity, dyslipidemia, diabetes and
hypertension affecting atherosclerosis as chronic, inflammatory process
with part of immune system and significant role for TNF-alfa , IL -1beta
and IL-6 (12,13).
The Japanese authors included subgroup of 36 468 survivors with analysis
for sociodemographic factors (education, occupation), lifestyle factors
(smoking, alcohol intake) as well as health variables (obesity, diabetes)
and showed a little effect on risk for any end point. We agree with
opinion of Mark P. Little, who suggested in letter to Editorials that
Japanese authors did not present data about other well known risk factors
for cardiovascular diseases, such dislipidemia (type), hypertension and
level of these disturbances as well as physical activity (14).
On the other hand, we studied activity of antioxidant erythrocyte enzymes
in X – ray department workers . Low activity was demonstrated compared
with control group, which suggested decreased antioxidant defense and
possible damage or functional changes of endothelium (1, 15).
We would like to emphasize value of the publication due to the analysis
of large group and indicate the possible link between cardiovascular
diseases and ionizing radiation. Influence of low doses of radiation on
public health seems to be important because recently reported increased
medical imaging procedures with the higher radiation exposure in some
patients compared with the staff of radiology clinics and nuclear
companies (16). Fazel et al. demonstrated that more than 30%of men and 40%
of women under age of 50 years received doses exceeding 20 mSv/year,
whereas in workers of health care and the nuclear industry cumulative
effective doses are restricted to 100 mSv ever 5 years (mean 20 mSv per
year) with maximal exposure of 50 mSv allowed in any given year. We
concluded, that the increasing exposure to low dose of radiation requires
new studies to explain association between such exposure and possible
development of cardiovascular diseases with monitoring of risk factors,
cumulative effective dose and inflammatory parameters.
1. Schultz-Hector S, Trott KR. Radiation-induced cardiovascular
diseases: is the epidemiologic evidence compatible with the radiobiologic
data? Int J Radiat Oncol Biol Phys 2007;67:10-8.
2. Hauptmann M, Mohan AK, Doody MM, Linet MS, Mabuchi K. Mortality from
diseases of the circulatory system in radiologic technologists in the
United States. Am J Epidemiol 2003;157:239-48.
3. Vrijheid M, Cardis E, Ashmore P, Auvinen A, Bae JM, Engels H, et al.
Mortality from diseases other than cancer following low doses of ionizing
radiation: results from the 15-Country Study of nuclear industry workers.
Int J Epidemiol 2007;36:1126-35.
4. Kreuzer M, Kreisheimer M, Kandel M, Schnelzer M, Tschense A, Grosche
B. Mortality from cardiovascular diseases in the German uranium miners
cohort study, 1946-1998. Radiat Environ Biophys 2006;45:159-66.
5. Muirhead CR, O’Hagan JA, Haylock RG, Phillipson MA, Willcock T,
Berridge GL, et al. Mortality and cancer incidence following occupational
radiation exposure: third analysis of the national registry for radiation
workers. Br J Cancer 2009;100:206-12.
6. Shimizu Y, Kodama K, Nishi N, Kasagi F, Suyama A, Soda M et al.
Radiation exposure and circulatory disease risk: Hiroshima and Nagasaki
atomic bomb survivor data, 1950-2003. BMJ 2010;340:b5349.
7. Hrycek A, Czernecka-Miciñska A, K³uciñski P, Badowski R. Peripheral
blood lymphocytes and selected serum interleukins in workers operating X-
ray equipment. Toxicol Lett 2002 ;132:101-17.
8. K³uciñski P, Mazur B, Kaufman J, Hrycek A, Cieœlik P, Martirosian G.
Assessment of blood serum immunoglobulin and C-reactive protein
concentrations in workers of x-ray diagnostics units. Int J Occup Med
Environ Health 2005;18:327-30.
9. K³uciñski P, Mazur B, Wiechu³a B, Maœluch E, Kaufman J, Hrycek A et al.
. Evaluation of cellular isoform of prion protein expression on the
surface peripheral blood monocytes and serum concentrations of interleukin
1β and interleukin 1β receptor antagonist in workers operating X
-ray equipment. Diagn Lab 2006; 42: 369-74.
10. K³uciñski P, Maœluch E, Wiechu³a B, Hrycek A, Mazur B, Kaufman J et
al. Serum concentrations of tumor necrosis factor α and its soluble
receptors TNFR1 and TNFR2 in workers of X-ray departments. Ann Acad Med
Siles 2006; 60: 308-11
11. Hayashi T, Morishita Y, Kubo Y, Kusunoki Y, Hayashi I, Kasagi F et al.
Long-term effects of radiation dose on inflammatory markers in atomic bomb
survivors. Am J Med 2005;118:83-6.
12. Ridker PM, Buring JE, Cook NR, Rifai N. C-reactive protein, the
metabolic syndrome, and risk of incident cardiovascular events: an 8-year
follow-up of 14 719 initially healthy American women. Circulation
2003;107:391-97.
13. de Winther MP, Kanters E, Kraal G, Hofker MH. Nuclear factor kappaB
signaling in atherogenesis. Arterioscler Thromb Vasc Biol 2005;25:904-14.
14. Little MP. Exposure to radiation and higher risk of circulatory
disease. BMJ 2010; 340: b4326-b4326
15. K³ucinski P, Wójcik A, Grabowska-Bochenek R, Gmiñski J, Mazur B,
Hrycek A et al. Erythrocyte antioxidant parameters in workers
occupationally exposed to low levels of ionizing radiation. Ann Agric
Environ Med 2008;15:9-12.
16. Fazel R, Krumholz HM, Wang Y, Ross JS, Chen J, Ting HH et al. Exposure
to low-dose ionizing radiation from medical imaging procedures. N Engl J
Med 2009;361:849-57.
Competing interests:
None declared
Competing interests: No competing interests