Download Linkage between cardiovascular disease and periodontitis : a puzzle

Possible Linkage between Cardiovascular Disease
and Periodontitis : A Survey
Abstract:
There have been numberious published studies describes
between oral conditions and cardiovascular disease. Recent research has
yielded conflicting data regarding the relationship between dental disease,
particularly periodontitis and cardiovascular disease. There is plausible
theoretical basis for such a link, as increased levels of inflammatory
mediators may increase the risk of atherosclertic plaque formation. Clinical
conformation and other studies of a causative relationship has been difficult
in part because cardiovascular disease and periodontal disease share
common risk factors. This article review’s possible evidence for relationship
between cardiovascular diseases and periodontitis.
Keyword: Periodontal disease, Cardiovascular disease, Survey.
Possible Linkage between Cardiovascular Disease
and Periodontitis : A Survey
Introduction:
Periodontal disease, a common chronic oral inflammatory
disease is characterized by destruction of soft tissue and bone of tooth.
Atheroclorosis starts early in life, since disease progression is usually slow,
clinical symptoms or hospitalization on are rare before 40 years of age.
Epidemiological associations between periodontitis and cardiovascular
disease have been reported.1,2 Periodontitis and atherosclerosis have
complex aetiologies, genetic and gender predispositions and may share
pathogenic mechanisms as well as common risk factors.
It is becoming increasingly clear that infections and chronic
inflammatory conditions such as periodontitis may influence the
atherosclerotic process. The crucial casual relation might be established by
prospective treatment studies, which elucidate the connection between
treatment of poor health and systemic inflammatory marker3-4. Haemostatic
and rheological variable are associated with both prevalent and incident
cardiovascular disease, and may be mechanisms through which risk factors
such as smoking, hyperlipidemia and infections may promote vascular
events. Low grade chronic infections are increasingly being recognized as
potential instigators of systemic diseases. Periodontal disease manifests as a
prevalent chronic infection impinging throughout the entire adult life in a
significant proportion of the population and is probably a significant risk
factor for cardiovascular disease in the population as a whole and
particularly in certain groups.5 This article review the link between
periodontitis and cardiovascular risk.
Cross sectional studies
Cross sectional studies type of studies are useful tool for
generation of hypothesis:
Sr. Author
Work done
Reference
No.
No.
1
Syrjanen et al. Dental infection was associated with 6
(1989)
cerebral infraction in young and middle
aged men
2.
Paunio
(1993)
3.
Mattila
(1993)
et
al. Missing teeth were associated with 7
ischemic heart disease
KJ Significant
association
between 8
clinically evident attachment loss and
self reported history of myocardial
infraction
4.
Loesche et al. A positive association between dental 9
(1998)
disease and cerebrovascular accident in
US Veterans
5.
Arbes
et
(1999)
6.
Slade
al. Statistical association between severity 10
of coronary artery stresses
et
(2000)
al. Edentulism and periodontal disease 11
associated with increased systemic
inflammatory
response,
even
with
adjustment for established risk factors
7.
Buhlin
(2002)
et
al. CVD was increased is the patient had 12
experienced problems with her/his
teeth in absence of dental care.
These type of studies are a wonderful tool for hypothesis
generation. Usually, they are not adjusted for all major co-existing risk
factors, and since the outcome (CHD) and the predictor (periodontal disease)
are measured at the same time, a temporal relationship cannot be established.
Hence, the strength of evidence for casual association is weak. Interference
from Table 1, inadequate prior dental histories and numerous factors such as
age, gender, smoking, diabetic, socio-economic and marital status and
education for the patients. Studies have shown a significant association
between disease and myocardial infarction, cerebrovascular accidents.
Case control studies : Case control studies generate the next level of
strength of evidence, although they are still laden with biases. These studies
generate the increase the level of strength of evidences, although they were
still laden with biases. A ideal case-control study requires that the disease
(CHD) be ascertained at the beginning of the study, and the past exposure,
according to the disease status has been assessed i.e. it must be ascertained
that the CHD patients and controls are similar in every aspect expect the
CHD status. These studies observed that strong association between
periodontal disease and cardiovascular disease (Table 2).
Table 2: Summaries of case control studies on relationships between
periodontal infections and cardiovascular disease (CVD)
Sr. Author
No.
1
Mattila
Work done
et
(1989 b)
Reference
No.
al. Total dental index (combined several 13
dental infections was
associated
with
acute
significantly
myocardial
infraction
2.
Grau
(1997)
et
al. Stroke victims tended to have more 14
severe periodontitis than controls
3.
Emingil
et
(2000)
al. Periodontal disease may have been 15
associated
with
acute
myocardial
infraction
4.
Maltila
et
(2000)
al. No significant association between 16
chronic (CAD) and severity as dental
disease
5.
Janket
et
al. No effects on each other
17
(2001)
6.
Reutger
person Periodontal disease may have been 18
et al. (2003)
associated with CAD was indeed
elevated
with
increasing
disease
severity of periodontal
7.
Maltila (2003)
Increased alveolar boneloss associated 19
with severity of cardiovascular disease
8.
Janket
(2004)
et
al. Oral health has the potential to affect 20
systemic health via more than just the
inflammatory process
Periodontal disease has been associated with increased risk of CAD and
CHD.
Longitudinal studies: This study design establishes the temporal relation
between a predictor and an outcome. These studies are equivocal about
periodontal disease involvement in development of CAD.
Table 3: Summaries of longitudinal studies on the relationship between
periodontal infections and coronary artery disease
Sr. Author
Work done
Reference
No.
No.
1.
De Stefano et al. Periodontal disease and tooth loss 21
(1993)
weakly
associated
with
CAD
development; stronger association for
subjects > 50 years old
2.
Maltila
et
(1995)
al. Statistical evidence for association 22
between
oral
infections
and
development of adverse cardiovascular
outcomes in patients at increased for
coronary artery disease (CAD)
3.
Beck
et
(1996)
al. Result
support
hypothesis
that 23
periodontal disease is involved in
development of CAD
4.
Genco
(1997)
et
al. Alveolar bone level predictive of 24
cardiovascular disease for persons < 60
years old
5.
Danesh
et
(1997)
6.
al. Significant association between the 25
number of teeth myocardial infraction
Morrison et al. Significant
(1999)
correlation
between 27
periodontal disease and risk of fatal
cardiovascular disease
7.
Saito
et
(1998)
8.
Hujoel
al. High BMI tend to exhibit poor 26
periodontal status
et
(2000)
al. Elimination of chronic dental infections 28
did not lead to reductions in risk of
CAD
9.
Howell
(2001)
et
al. Self reported periodontal disease not an 29
independent predictor of cardiovascular
disease in middle aged to elderly men
when adjusted for major cardiovascular
risk factors
10.
Tuominen et al. The association between oral health 30
(2003)
and fatal CAD might simply be due to
behavioral factors
11.
Scannapieco
al. (2003)
et There is insufficient evidence available 31
to justify periodontal intervention to
prevent the onset or progression of
atherosclerosis induced diseases
Systemic markers of inflammation:
Most systemic markers of inflammation are regarded as
predictive markers for cardiovascular diseases. These markers include
leukocytes count (WBC), C-reactive proteins (CRP), fibronogen and lipid
profile. Raised WBC counts, CRP and fibrinogen levels correlated with
periodontal disease (Table 4-6). On the other hand HDL levels are found to
be lowered in this condition. (Table 7), haemotocrit value and thrombocyte
counts are lowered in periodontal condition disease (Table 7). From the
available literature it is appears that the total number of leukocytes and
plasma levels of C-reactive protein are consistently higher in periodontitis
patients compared to healthy control. Number of red blood cells and the
levels of heamoglobin are lower in periodontitis and those as a trend towards
anemia of chronic disease. Most systemic markers of inflammation diseased
(Table 4 to 8) regarded as predictive markers for cardiovascular disease.
Hence, analogous to other infections inflammatory diseases, it is conceivable
that the chronically, slightly elevated or depressed systemic markers in blood
exacerbated ongoing inflammatory process in other organ systems and this
way perhaps increase the risk for atherosclerosis, leading to cardiovascular
and cerebrosvascular events.
Table 4: Summaries of leukocytes in periodontitis and healthy controls
Sr.
No.
1
Authors
Gustafsson
Leukocytes
mean+SD
Periodontitis
al. 7.7 + 2.1
(x109/l)
Reference
Controls
7.3 + 2.2
32
5.6 + 1.1
33
6.5 + 1.9
5.8 + 1.4
34
et
al. 6.6 + 1.7
5.9 + 1.3
35
et
al. 7.3 + 2.3
5.7 + 1.3
36
8.0 + 2.2
7.2 + 2.2
37
et
(1996)
2
Frederiksson et al. 7.0 + 1.4
(1998)
3
Loss et al. (2000)
4
Fokhema
(2002)
5
Bizzarro
(2005)
6
Rai et al. (2006)
Table 5: Summaries of c-reactive protein (CRP) plasma level (mg/l) in
periodontitis and healthy controls
Sr.
No.
1
(CRP)
Authors
Patients
Controls
Frederiksson et al. 2.62 + 2.90
0.80 + 1.73
Reference
33
(1998)
2
Loss et al. (2000)
2.64 + 3.48
1.21 + 1.34
34
3
Noack et al. (2001)
4.06 + 5.55
1.70 + 1.91
38
4
Glurich et al. (2002) 2.40 + 1.80
1.68 + 1.42
39
5
Craig et al. (2003)
5.78 + 1.07
2.46 + 1.44
40
6
Bizzarro
al. 3.12 + 3.81
1.88 + 2.04
36
3.82 + 0.33
1.42 + 0.43
41
et
(2005)
7
Rai et al. (2006)
Table 6: Summaries of fibrinogen plasma level (g/l) in periodontitis patients
and healthy controls
Sr.
No.
1
Fibrinogen plasma level
Authors
Patients
Controls
Shingur et al. (2003) 2.50 + 0.10
2.25 + 0.12
Reference
42
2
Bizzarro
36
(2005)
et
al. 3.26 + 0.68
2.90 + 0.63
Table 7: Summaries of some other value of periodontitis and normal healthy
controls
Sr. Authors
No.
1
Christan
Work done
et
Reference
al. Non-surgical periodontal therapy 43
(2002)
among 27 patients with aggressive
periodontal resulted in a reduced of
numbers of thromocytes in the
peripheral circulation : the media
value at baseline of 2.6 x 1011/l was
reduced after therapy to 2.3 x 1011/l
2
Hutler et al. (2001)
Periodontitis is a disease process 44
which can result in a form of
anemia periodontitis patients have
lower hematocrit
3
Lainson et al.(1968) 58% of female periodontitis patients 45
and 30% of male periodontitis
patients had a depressed hematocrit
4
Loos et al. (2000)
11 of 26 control subjects (42%) and 34
47 of 88 periodontitis patients
(53%) had mearable IL-6 in plasma.
The Il-6 levels, like CRP, showed a
positive relation to extent of disease
5
Buhlin et al. (2003)
Elevated IL-6 plasma levels in 46
patients with severe periodontitis
compared to healthy controls
Table 8: Summaries of lipid profile in periodontitis and normal healthy
controls
Sr.
No. Authors
1
Work done
Reference
Katz et al. (2002)
Periodontal disease may influence 47
blood lipid concentrations
2
Buhlin’s
(2001)
3
et
al. Relation between periodontitis and 48
low concentrations of HDL
Joshipura
et Periodontal disease was associated 49
al.(2004)
with higher levels of LDL as
compared to healthy
Table 9: Summaries of oral health and stroke relationship
Sr. Authors
No.
1
Work done
Beck et al. (1996)
Strong
association
periodontitis
with
Reference
between 22
incidence
of
stroke among US veterans
2
Morrison
et
al. No-significant increase in risk of 50
(2001)
3
4
Joshipura
fatal stroke in periodontitis patients
et A significant association between 51
al.(2003)
stroke and periodontitis
Janket et al. (2003)
Relationship between periodontal 52
disease and stroke to be much
stronger that periodontal disease
and CHD
Table 10: Summaries the ratio for cardiovascular disease for patients with
periodontal disease
Sr. Authors
No.
1
De stefano et al. 1.46
(1993)
Ratio (fatal cardiovascular
disease/stroke)
Reference
21
2
Beck et al. (1996)
1.9/2.8
23
3
Gran et al. (1997)
2.6
14
Thus poor oral health in term in terms of periodontitis has strong
relationship between CHD and stroke in most of the studies reviewed (Table
10).
Table 11: Summaries of microbiological aspect of periodontitis and
cardiovascular disease
Sr. Authors
No.
1
Herzberg
Work done
et
(1990)
Reference
al. Oral bacteria such as streptococous 53
sanguis
and
gingivalis
porphyromanas
induce
platelet
aggression; which lead to thrombus
formation
2
Page et al. (1998)
Lipopolysacchride
and
gram 54
negative oral bacteria may enter the
blood
stream
and
increase
susceptibility to systemic disease
3
Sacransky
et
(2002)
al. P. gingivalis can actively adhere to 55
and invade fotal bovine
heart
endothelial
cells,
bovine
arotic
endothelial
cells,
and
human
umbilical vein endothelial cells
4
Wolf et al. (2003)
Oral pathogens are not the only 56
bacteria that have a postulated link
to
the
development
atherosclerosis
of
chlamydia
pneumoniae anid H. pylori are also
suspected
infectious
agents
in
atherogenesis
Conclusion:
The debate about whether periodontal disease is a risk factor for
cardiovascular disease is interesting, but still unresolved. Current evidence is
insufficient to unequivocally support the premise that dental infections
constitute an independent risk factor for cardiovascular disease. However,
the deposition of atherematous plaque in the coronary arteries may be
associated with many other infections in addition to periodontitis. Although
some studies have demonstrated that the relative risk for cardiovascular
disease is increased among patients with periodontitis, other analysis have
been potentially confounded by the fact that smoking and diabetes seen to
have a casual relationship with cardiovascular disease and periodontitis. As
long as the mechanism of cardiovascular remains obscure, it will be difficult
to determine the real relationship between oral and cardiovascular disease.
Therefore, evidence for potential association between oral and systemic
disease must be carefully reexamined to distinguish potential confounding
factors from other risk factors before treatment with the aim of preventing or
treating cardiovascular disease can be justified.
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