| MICRONUTRIENTS
AND TRACE ELEMENTS IN ACUTE MYOCARDIAL INFARCTION |
| Sreekanth KS, Geevar
Zachariah, Annamalai PT |
 |
Departments
of Clinical Biochemistry and Cardiology, Amala
Cancer Hospital and Research Centre, Amala
Nagar, Thrissur - 680 553, Kerala. |
|
| |
 SUMMARY |
| |
| Acute myocardial infarction (AMI)
continues to be a major public health problem in
the developing world, despite impressive strides
made in its diagnosis and management. Among the
several causes of the disease alteration in the
levels of micronutrients and trace elements are
also important. The present study was focused on
the alteration of these elements in AMI patients
as compared to that of the healthy individuals and
their changes depending up on different risk factors.
The present study included 300 AMI patients and
100 healthy individuals as controls. We observed
a decreased value of vitamin E, vitamin C, zinc
and magnesium (p<0.01) in the serum of AMI patients
when compared to that of the normal controls. However
the values of iron, % transferrin saturation and
ferritin were found to be significantly increased
in these patients (p<0.01), but the value of
total iron binding capacity was found to be significantly
decreased (p<0.01) in AMI patients. The distributions
of these parameters were significantly differed
among various risk factors studied. |
| |
|
INTRODUCTION |
| |
| Acute myocardial infarction (AMI),
an important manifestation of coronary artery disease
(CAD) is emerging as one of the major cause of mortality
worldwide. Several factors have been attributed
for the cause of the disease. But the exact mechanism
responsible for the cause and complication is still
unknown. Micronutrients and trace elements are very
essential for the normal functioning of the body.
Even though they are required in very small amounts,
an alteration in the level of these elements may
lead to serious impairments which in turn lead to
diseases like CAD. Prospective studies have demonstrated
reduced risk of coronary artery disease in subjects
with a greater intake of vitamin E1
or vitamin C2, because
these antioxidant vitamins inhibit oxidation of
low-density lipoprotein (LDL), a critical event
in the coronary artery disease. Further vitamin
E and vitamin C, the two essential micronutrients,
is capable to remove the oxygen-derived free radicals
by virtue of their antioxidant property. |
| |
| The role of essential micronutrient
metals in lipid metabolism is of recent investigation.
The metabolism of zinc (Zn) is significantly altered
in patients with cardiovascular disease as evidenced
by abnormally low plasma or serum concentrations
of zinc. Recent studies have shown a relationship
between zinc status and the metabolism of cholesterol
and lipoproteins3.
Magnesium (Mg), another trace element is essential
for the activation of a variety of enzymes involved
in cellular metabolism, especially in neurochemical
transmission and muscular activity. It has been
shown that magnesium depletion modifies coronary
blood flow, blood clotting and atherogenesis 4.
There is a strong relationship between iron levels
and cardiovascular disease. It has been observed
that the amount of iron has been increased considerably
in patients with acute myocardial infarction, which
in turn can stimulate the lipid peroxidation5. |
| |
| The present
study evaluate the role of the trace elements such
as iron, zinc and magnesium and micronutrients such
as vitamin E and vitamin C along with ferritin,
total iron binding capacity and % transferrin saturation
in patients with acute myocardial infarction and
their sequential variation in the complication of
acute myocardial infarction associated with different
risk factors taken in to account. |
| |
|
MATERIALS AND METHODS |
| |
| The study period was from November
1999 to September 2003. All patients admitted to
the Intensive Coronary Care Unit (ICCU) of Amala
Cancer Hospital with a diagnosis of acute myocardial
infarction presenting within 24 hours of onset of
chest pain during this period were included in the
study. Present study included 300 AMI patients and
100 sex and age matched control subjects. Myocardial
infarction was diagnosed by at least 0.1-mv ST segment
elevation in two or more contiguous limb leads or
0.2-mv ST segment elevation in two or more chest
leads associated with typical chest pain. Patients
with cardiogenic shock, cerebrovascular accident
and significant hepatic or renal disease were excluded.
Patients with clear evidence of infection anywhere
in the body were also excluded. |
| |
| In patients included in the study,
detailed history was taken and complete physical
examination was carried out by the cardiologist.
A 12 lead ECG with V3R
and V4R is recorded
immediately on admission and repeated after 2hrs,
6hrs, 12hrs, 24hrs, 48hrs and pre-discharge. 10ml
blood was withdrawn for laboratory analysis. Serial
creatine kinase assays were also done to confirm
the myocardial infarction and it was done at 2hrs,
6hrs, 12hrs, 24hrs, 48hrs after admission. Chest
X- ray was done at the time of discharge from the
ICCU. An echocardiographic examination was performed
at the time of discharge or at the end of the first
week or early second week after admission. All patients
were seen in the cardiology out-patient department
4 to 6 weeks after discharge, when a detailed history
was taken and complete physical examination was
again carried out. A symptom limited treadmill test
was done as per the Bruce protocol and maximum heart
rate (HR), blood pressure (BP), double product,
time to 1 mm ST depression, metabolic equivalences
(METs) achieved, duration of exercise, angina, dyspnea
and arrhythmias were recorded along with ST segment
changes. |
| |
| The normal volunteers had no past
history or evidence of cardiovascular disease, hypertension
or diabetes mellitus. The present study does not
include control subjects with a history of neoplastic,
hepatic, infectious or autoimmune disease or any
surgical procedure in the preceding 6 months. |
| |
| The patients were allowed to relax
and on the second day they were subjected to an
oral questionnaire as described in our Performa,
in order to collect the history of these patients.
They were asked about the type of chest pain, the
time of onset of the pain, radiation to other parts
of the body and any previous history of chest pain.
They were also asked about the symptoms associated
with the chest pain, history of diabetes, history
of hypertension, habits of smoking or alcohol or
pan chewing, food habits (vegetarians or non vegetarians)
and any positive family history of AMI. Then these
patients were categorized according to the following
risk factors and based on these risk factors the
study has been designed. |
| |
1) Age and sex
2) Time of onset of chest pain
3) History of diabetes and hypertension
4) A cholesterol value of <200 mg/dl and >200
mg/dl
5) Habits of smoking and alcohol intake
6) Food habits and a positive and negative family
history of AMI. |
| |
| Plasma tocopherol was assayed using
the Emmeric Engel reaction6,
Vitamin C was done by the photometric reduction
method7, Zinc in
the serum was detected by the Nitro-PAPS method8
and magnesium was done by the Xylidyl blue method9.
Iron was estimated by the reaction with a, a'-dipyridyl10,
Total Iron Binding Capacity (TIBC) was done by the
addition of magnesium carbonate, and then following
the same reaction for iron 11.
Percentage saturation of transferrin was done by
using the formula: (iron/TIBC) X 10012
and ferritin was estimated in the serum by a solid
phase enzyme linked immunosorbent assay (ELISA)13.
The statistical analysis was done by using the 'z-
test' and the inter group comparison were done by
the analysis of variance (ANOVA)14. |
| |
|
RESULTS |
| |
| Table 1 represents the values of micronutrients
and trace elements in normal and in AMI patients.
Here the values of vitamin E, vitamin C, Zn and
Mg were found to be decreased significantly (p<0.01)
in the serum of the AMI patients when compared to
that of the normal controls. |
| |
| Table 1: Values of micronutrients
and trace elements in various groups |
| |
| Parameters |
Groups |
| |
Normal
(n=100) |
AMI
(n=300) |
| Vitamin
E (mg/dl) |
5.94±
0.82 |
2.89±
0.75** |
| Vitamin
C (mg/dl) |
1.19±
0.22 |
0.24±
0.13** |
| Zn
(mg/dl) |
48.71±
8.71** |
88.82
± 12.04 |
| Mg
(mg/dl) |
0.73
± 0.36** |
2.31
± 0.30 |
|
| |
| Values are mean ± SD,
**p<0.01 |
| |
| Table 2: Micronutrients and
trace elements in normal and in AMI patients according
to age and sex |
| |
| Parameters |
Age (years) |
Sex |
| |
<40 |
40-60 |
>60 |
Male |
Female |
| |
Normal n=22 |
AMI n=27 |
Normal n=54 |
AMI n=160 |
Normal n=24 |
AMI n=113 |
Normal n=85 |
AMI n=261 |
Normal n=15 |
AMI n=39 |
| Vitamin E (mg/dl) |
5.80±0.86 |
2.56±0.11* |
6.03±0.80 |
2.98±0.778* |
5.86±0.79 |
2.84±0.55* |
5.95±0.82 |
2.89±0.78* |
5.88±0.80 |
2.84±0.56* |
| Vitamin C (mg/dl) |
1.15±0.24 |
0.19±0.13* |
1.21±0.22 |
0.23±0.14* |
1.19±0.21 |
0.27±0.12* |
1.19±0.23 |
0.23±0.13* |
1.20±0.22 |
0.29±0.12* |
| Zn (mg/dl) |
89.47±12.08 |
51.00±8.42* |
88.62±11.74 |
48.08±9.01* |
88.69±12.64 |
49.04±8.31* |
89.15±11.95 |
48.57±8.84 |
87.00±12.36 |
49.64±8.01* |
| Mg (mg/dl) |
2.19±0.27 |
0.72±0.29* |
2.36±0.29 |
0.63±0.31* |
2.29±0.30 |
0.87±0.39* |
2.30±0.30 |
0.71±0.35* |
2.36±0.29 |
0.90±0.37* |
|
| |
| Values are mean ±SD;
* p<0.01. |
| |
Table 2 represents the values of micronutrients
and trace elements in normal and in AMI patients
according to the age and sex. Irrespective of the
age and sex the values of all these parameters were
significantly decreased (p<0.01) in all the groups
when compared to that of their respective controls.
Among the age groups the value of vitamin C was
found to be significantly decreased in AMI patients
with age 40
years when compared to the other two groups and
the value Mg was found to be decreased significantly
in AMI patients with age ranges from 40-60 years,
when compared to that of the other two groups. Vitamin
E and Zn did not show any significant variation
among the groups. The values of vitamin C and Mg
were found to be significantly decreased in AMI
males when compared to that of AMI females. Here
also the values of vitamin E and Zn did not show
much alteration between the groups. |
| |
| Table 3: Micronutrients and
trace elements according to the time of onset of
chest pain |
| |
| Parameters |
|
Time of onset
of chest pain |
| |
Normal |
Acute
MI |
| |
|
12am to 6 am (n=50) |
6 am to 12 noon (n=94) |
12 noon to 6 pm (n-90) |
6 pm to 12 am (n=66) |
| Vitamin E (mg/dl) |
5.94±0.82 |
2.51±088* |
2.79±0.67* |
3.25±0.75* |
2.82±0.55* |
| Vitamin C (mg/dl) |
1.19±0.22 |
0.21±0.14* |
0.24±0.16* |
0.22±0.11* |
0.29±0.11* |
| Zn (mg/dl) |
88.82±12.04 |
49.13±7.93* |
47.66±8.01* |
48.60±10.39* |
50.03±7.54* |
| Mg (mg/dl) |
2.31±0.30 |
0.67±0.26* |
0.65±0.35* |
0.71±0.35* |
0.92±0.38* |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 4: Micronutrients and
trace elements in patients with diabetes and hypertension |
| |
| Parameters |
|
Acute MI |
| |
Normal |
Diabetes |
Hypertension |
| |
|
Diabetes (n=101) |
No diabetes (n=199) |
Hypertension (n=62) |
No hypertension
(n=238) |
| Vitamin E (mg/dl) |
5.94+0.82 |
2.51+0.74* |
3.08+0.69* |
2.62+0.56* |
2.95+0.78* |
| Vitamin C (mg/dl) |
1.19+0.22 |
0.21+0.15* |
0.25+0.12* |
0.22+0.16* |
0.24+0.13 |
| Zn (mg/dl) |
88.82+12.04 |
47.65+8.24* |
49.24+8.88* |
16.55+8.48* |
49.27+8.71* |
| Mg (mg/dl) |
2.31+0.30 |
0.65+0.28* |
0.77+0.38* |
0.65+0.32* |
0.75+0.37* |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 3 represents the values of micronutrients
and trace elements in normal and in AMI patients
according to the time of onset of chest pain. Here
the values of vitamin E, vitamin C, Zn and Mg were
found to be significantly decreased (p<0.01)
in all the AMI patients with different time of onset
of chest pain. The values of vitamin E and vitamin
C were found to be significantly altered in AMI
patients with onset of chest pain from 12 midnight
to 6 am when compared to the other three groups.
The value of Mg was found to be significantly altered
in AMI patients with onset of chest pain from 6
am to 12 noon when compared to the other three groups.
However the value of Zn was not differed significantly
among the groups with different time of onset of
chest pain. |
| |
| Table 4 represents the values of micronutrients
and trace elements in normal and in AMI patients
with the history of diabetes and hypertension. Here
the values of these micronutrients and trace elements
were found to be decreased significantly (p<0.01)
in AMI patients with and without the history of
diabetics and hypertension when compared to that
of the normal healthy individuals. A comparison
of AMI patients with and without the history of
diabetes have shown the significant values of vitamin
E, vitamin C and Mg in AMI patients with the history
of diabetes when compared to AMI patients without
the history of diabetes. However the values of Zn
did not show any significant difference between
these two groups. A comparison between the AMI patients
with and without the history of hypertension has
shown significant values of Zn and Mg in AMI patients
with the history of hypertension when compared to
that of the AMI patients without the history of
hypertension. Vitamin E and vitamin C did not differ
between these groups. |
| |
| Table 5: Micronutrients and
trace elements according to blood cholesterol |
| |
| Parameters |
|
Acute MI |
| |
Normal |
Cholesterol |
| |
|
> 200 mg/dl (n=105 |
<200 mg/dl (n=195) |
| Vitamin E (mg/dl) |
5.94±0.82 |
2.51±0.72* |
3.09±0.69* |
| Vitamin C (mg/dl) |
1.19±0.22 |
0.21±0.16* |
0.25±0.12* |
| Zn (mg/dl) |
88.82±12.04 |
47.22±8.36* |
49.51±8.77* |
| Mg (mg/dl) |
2.31±0.30 |
0.64±0.28* |
0.78±0.38* |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 5 gives the values of micronutrients
and trace elements in normal and in AMI patients
according to the values of cholesterol. Here the
values of vitamin E, vitamin C, Zn and Mg were found
to be significantly decreased (p<0.01) in AMI
patients with cholesterol value >200 mg/dl and
<200 mg/dl. A comparison between the values of
these micronutrients and trace elements in AMI patients
with cholesterol value>200 mg/dl and <200
mg/dl have shown significant values of vitamin E,
Zn and Mg in AMI patients with cholesterol value>200
mg/dl when compared to AMI patients with cholesterol
value <200 mg/dl. The value of vitamin C was
found to be unaltered between these two groups. |
| |
| Table 6: Micronutrients and
trace elements according to habits of smoking and
alcohol intake |
| |
| Parameters |
Smoking |
Alcohol intake |
| |
Yes |
No |
Yes |
No |
| |
Normal (n=62) |
AMI (n=222) |
Normal (n=38) |
AMI (n=78) |
Normal (n=20) |
AMI (n=160) |
Normal (n=80) |
AMI (n=140) |
| Vitamin E (mg/dl) |
5.90±0.81 |
2.91±0.82* |
6.00±0.81 |
2.82±0.54* |
5.85±0.89 |
2.99±0.80* |
5.96±0.79 |
2.80±0.69* |
| Vitamin C (mg/dl) |
1.18±0.23 |
0.22±0.14* |
1.20±0.21 |
0.28±0.12* |
1.15±0.25 |
0.22±0.15* |
1.20±0.22 |
0.25±0.11* |
| Zn (mg/dl) |
89.17±11.40 |
48.42±9.03* |
88.26±13.03 |
49.52±7.81* |
89.24±12.64 |
48.70±8.66* |
88.71±11.91 |
48.72±8.81* |
| Mg (mg/dl) |
2.28±0.29 |
0.68±0.33* |
2.36±0.30 |
0.88±0.39* |
2.17±0.27 |
0.66±0.32* |
2.35±0.29 |
0.81±0.39* |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 7: Micronutrients and
trace elements according to food habits and family
history |
| |
| Parameters |
Food habits |
Family history |
| |
Vegetarians |
Non
vegetarians |
|
AMI |
| |
Normal (n=16) |
AMI (n=27) |
Normal (n=84) |
AMI (n=273) |
Normal (n=100) |
Positive (n=82) |
Negative (n=218) |
| Vitamin E (mg/dl) |
5.84±0.78 |
3.88±0.60* |
5.96±0.82 |
2.79±0.69* |
5.94±0.82 |
3.36±0.73* |
2.71±0.69* |
| Vitamin C (mg/dl) |
1.12±0.22 |
0.21±0.11* |
1.19±0.23 |
0.24±0.14* |
1.19±0.22 |
0.25±0.15* |
0.23±0.13* |
| Zn (mg/dl) |
87.34±12.04 |
46.32±9.43* |
89.11±12.06 |
48.94±8.60* |
88.82±12.64 |
47.85±8.66* |
49.03±8.71* |
| Mg (mg/dl) |
2.39±0.31 |
1.02±0.32* |
2.29±0.29 |
0.70±0.35* |
2.31±0.30 |
0.74±0.35* |
0.73±0.36* |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 6 represents the values of micronutrients
and trace elements in normal and in AMI patients
according to the habit of smoking and alcohol intake.
Here the values of vitamin E, vitamin C, Zn and
Mg were found to be significantly decreased (p<0.01)
in AMI patients with and without the habits of smoking
and alcohol intake when compared to their respective
controls. A comparison of AMI patients with and
without the habit of smoking has shown significant
values of vitamin C and Mg in AMI patients with
the habit of smoking when compared to that of the
AMI patients without the habit of smoking. Vitamin
E and Zn did not show any significant alteration
between the groups. A comparison between the AMI
patients with and without the habit of alcohol intake
have shown significant value of Mg in AMI patients
with the habit of alcohol intake when compared to
AMI patients without the habit of alcohol intake.
The values of vitamin E, vitamin C and Zn were unaltered
between these two groups. |
| |
| Table 7 represents the values of micronutrients
and trace elements in normal and in AMI patients
according to the food habits and family history
of AMI. The values of all these micronutrients and
trace elements were found to be significantly decreased
(p<0.01) in AMI patients with the habit of both
vegetarian and non vegetarian food intake and with
and without the family history of AMI. A comparison
between the AMI patients with vegetarian and non
vegetarian food intake have shown significant value
of vitamin E and Mg in AMI patients with the habit
of non vegetarian food intake when compared to that
of the AMI patients with the habit of vegetarian
food intake. The values of vitamin C and Zn were
found to be unaltered between these groups. A comparison
between the AMI patients with and without the family
history of AMI have shown the significant value
of vitamin E in AMI patients without the family
history of AMI when compared to AMI patients with
the family history of AMI. The values of vitamin
C, Zn and Mg were found to be unaltered between
these groups. |
| |
| Table 8 represents the values of
iron, TIBC, %transferrin saturation and ferritin
in normal and in AMI patients. The values of iron,
%transferrin saturation and ferritin were found
to be significantly increased (p<0.01) in AMI
patients when compared to that of the normal controls.
However the value of TIBC was found to be significantly
decreased (p<0.01) in AMI patients when compared
to that of the normal controls. |
| |
| Table 8: Values of iron, transferrin
saturation (%) and ferritin in normal and AMI patients |
| |
| Parameters |
Groups |
| |
Normal (n=100) |
AMI (n=300) |
| Iron (mg/dl) |
99.67±13.51 |
154.96±23.08* |
| TIBC (mg/dl) |
324.74±15.84 |
256.21±24.16* |
| Transferrin
saturation % |
30.68±4.35 |
59.87±4.00 |
| Ferritin (ng/ml) |
65.78±12.78 |
131.3±24.76 |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 9 represents the values of iron,
TIBC, %transferrin saturation and ferritin in normal
and in AMI patients according to the age and sex.
Here the values of iron, %transferrin saturation
and ferritin were found to be significantly elevated
(p<0.01) in AMI patients with different age groups
and sex when compared to that of the normal controls.
The value of TIBC was found to be significantly
decreased (p<0.01) in AMI patients with different
age groups and sex when compared to that of the
normal controls. |
| |
| Table 9: Iron, TIBC, transferrin
and ferritin concentrations according to age and
sex |
| |
| Parameters |
Age (years) |
Sex |
| |
<40 |
40-60 |
>60 |
Male |
Female |
| |
Normal n=22 |
AMI n=27 |
Normal n=54 |
AMI n=160 |
Normal n=24 |
AMI n=113 |
Normal n=85 |
AMI n=261 |
Normal n=15 |
AMI n=39 |
| Iron (mg/dl) |
99.16±11.34 |
151.57±24.57* |
100.71±13.62 |
155.83±23.17* |
97.80±14.79 |
154.52±22.45* |
100.07±12.93 |
155.67±23.23* |
97.39±16.19 |
150.20±21.34* |
| TIBC (mg/dl) |
315.72±15.91 |
251.56±24.57* |
329.52±14.96 |
257.32±24.10* |
322.25±13.30 |
255.74±24.01* |
325.19±16.03 |
256.74±24.22* |
322.20±14.42 |
252.64±23.45* |
Transferrin_
saturation % |
31.12±3.46 |
59.85±3.92* |
30.58±4.47 |
60.37±4.16* |
30.51±4.76 |
60.22±3.78* |
30.62±4.35 |
60.35±4.09* |
31.05±4.33 |
59.62±3.30* |
| Ferritin (ng/ml) |
67.55±8.85 |
128.98±40.17* |
69.81±10.44 |
131.89±22.98* |
55.08±14.48 |
131.09±22.19* |
67.88±11.74 |
131.76±25.37* |
53.86±11.87 |
128.42±20.01* |
|
| Values are mean ±SD;
* p<0.01. |
| |
| Table 10: Iron, TIBC, transferrin
and ferritin concentrations according to the time
of onset of chest pain |
| |
| Parameters |
|
Time of onset
of chest pain |
| |
Normal (n=100) |
Acute MI |
| |
12am to 6 am (n=50) |
6 am to 12 noon
(n=94) |
12 noon to 6 pm
(n-90) |
6 pm to 12 am (n=66) |
| Iron (mg/dl) |
99.67±13.51 |
154.84±26.36* |
156.11±22.52* |
154.28±22.11* |
154.31±22.40* |
| TIBC (mg/dl) |
324.74±15.84 |
254.54±26.66* |
258.28±24.04* |
256.24±23.01* |
254.47±23.68* |
| Transferrin
saturation % |
30.68±4.35 |
60.27±4.28* |
60.16±4.33* |
60.48±3.83* |
60.11±3.48* |
| Ferritin (ng/ml) |
65.78±12.78 |
128.33±35.52* |
129.82±221.94* |
136.29±22.00* |
129.73±20.88* |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 11: Iron, TIBC, transferrin
and ferritin concentrations in patients with diabetes
and hypertension |
| |
| Parameters |
|
Acute MI |
| |
Normal (n=100) |
Diabetes |
Hypertension |
| |
Diabetes (n=101) |
No diabetes (n=199) |
Hypertension (n=62) |
No hypertension
(n=238) |
| Iron (mg/dl) |
99.67±13.51 |
154.80±24.47* |
155.03±22.33* |
155.19±25.07* |
154.89±22.51* |
| TIBC (mg/dl) |
324.74±15.84 |
255.92±23.06* |
256.78±26.17* |
255.89±24.43* |
256.29±24.10* |
| Transferrin
saturation % |
30.68±4.35 |
59.88±4.57* |
60.46±3.67* |
60.06±3.87* |
60.32±4.04* |
| Ferritin (ng/ml) |
65.78±12.78 |
127.25±29.42* |
133.39±21.73* |
128.76±23.15 |
132.00±25.11* |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 10 represents the values of
iron, TIBC, %transferrin saturation and ferritin
in normal and in AMI patients according to the time
of onset of chest pain. The values of iron, %transferrin
saturation and Ferritin were found to be significantly
increased (p<0.01) in AMI patients with different
time of onset of chest pain when compared to that
of the normal controls. The value of TIBC was found
to be significantly decreased (p<0.01) in AMI
patients with different time onset of chest pain
when compared to that of the normal controls. A
comparison between AMI patients with different time
of onset of chest pain have shown significant value
of ferritin in AMI patients with time of onset of
chest pain from 12 midnight to 6 am when compared
to the other three groups. The values of iron, TIBC
and %transferrin saturation were remained unaltered
between the groups. |
| |
| Table 11 represents the values of
iron, TIBC, %transferrin saturation and ferritin
in normal and in AMI patients with and without the
history of diabetes and hypertension. Here the values
of iron, %transferrin saturation and ferritin were
found to be significantly increased (p<0.01)
in AMI patients with and without the history of
diabetes and hypertension when compared to that
of the normal controls. The value of TIBC was found
to be significantly decreased (p<0.01) in AMI
patients with and without the history of diabetes
and hypertension when compared to that of the normal
controls. |
| |
| Table 12 represents the values of
iron, TIBC, %transferrin saturation and ferritin
in normal and in AMI patients according to the values
of cholesterol. The values of iron, %transferrin
saturation and ferritin were found to be significantly
increased (p<0.01) in AMI patients with cholesterol
values >200 mg/dl and <200 mg/dl when compared
to that of the normal controls. The value of TIBC
was found to be significantly decreased (p<0.01)
in AMI patients with cholesterol values >200
mg/dl and <200 mg/dl when compared to that of
the normal controls. |
| |
| Table 12: Iron, TIBC, transferrin
and ferritin concentrations in patients with diabetes
and hypertension |
| |
| Parameters |
|
Acute MI |
| |
Normal |
Cholesterol |
| |
|
> 200 mg/dl (n=105 |
<200 mg/dl (n=195) |
| Iron (mg/dl) |
99.67±13.51 |
155.02±24.89* |
154.92±22.02* |
| TIBC (mg/dl) |
324.74±15.84 |
257.38±25.98* |
255.57±23.11* |
| Transferrin
saturation % |
30.68±4.35 |
60.01±4.54* |
60.41±3.68* |
| Ferritin (ng/ml) |
65.78±12.78 |
127.58±29.10* |
133.34±21.79* |
|
| Values are mean±SD; *
p<0.01 |
| |
| Table 13 represents the values of
iron, TIBC, %transferrin saturation and ferritin
in normal and in AMI patients according to the habit
of smoking and alcohol intake. The values of iron,
%transferrin saturation and ferritin were found
to be significantly increased (p<0.01) in AMI
patients with and without the habits of smoking
and alcohol intake when compared to that of the
normal controls. However the value of TIBC was found
to be significantly decreased (p<0.01) in AMI
patients with and without the habits of smoking
and alcohol intake when compared to that of the
normal controls. |
| |
| Table 13: Iron, TIBC, transferrin
and ferritin concentrations according to habits
of smoking and alcohol intake |
| |
| Parameters |
Smoking |
Alcohol intake |
| |
Yes |
No |
Yes |
No |
| |
Normal (n=62) |
AMI (n=222) |
Normal (n=38) |
AMI (n=78) |
Normal (n=20) |
AMI (n=160) |
Normal (n=80) |
AMI (n=140) |
| Iron (mg/dl) |
100.99±11.78 |
155.58±23.2* |
97.51±15.62 |
153.15±22.53* |
98.53±11.53 |
156.18±23.83* |
99.95±13.92 |
153.56±22.09* |
| TIBC (mg/dl) |
324.95±16.76 |
256.77±24.26* |
324.41±14.17 |
254.61±23.81* |
315.83±16.64 |
257.22±24.47* |
326.97±14.79 |
255.06±23.76* |
| Transferrin_saturation
% |
31.01±3.84 |
60.39±4.10* |
30.14±5.03 |
59.91±3.69* |
30.98±3.51 |
60.30±4.20* |
30.61±4.53 |
60.22±3.76* |
| Ferritin (ng/ml) |
68.40±10.69 |
132.13±25.90* |
61.50±14.59 |
129.06±21.00* |
66.80±8.81 |
130.17±26.62* |
65.53±13.56 |
132.65±22.36* |
|
| Values are mean ±SD;
* p<0.01. |
| |
| Table 14: Iron, TIBC, transferrin
and ferritin concentrations according to food habits
and family history |
| |
| Parameters |
Food habits |
Family history |
| |
Vegetarians |
Non vegetarians |
|
AMI |
| |
Normal (n=16) |
AMI (n=27) |
Normal (n=84) |
AMI (n=273) |
Normal (n=100) |
Positive (n=82) |
Negative (n=218) |
| Iron (mg/dl) |
97.57±15.68 |
152.68±22.49* |
100.07±13.01 |
155.18±23.11* |
99.67±13.51 |
156.88±20.97* |
154.23±20.67* |
| TIBC (mg/dl) |
322.94±14.24 |
254.36±24.81* |
325.09±16.09 |
256.39±24.08* |
324.74±15.84 |
257.04±23.97* |
255.89±24.22* |
| Transferrin_saturation
% |
30.38±4.93 |
59.73±3.32* |
30.74±4.22 |
60.32±4.06* |
30.68±4.35 |
61.12±3.69* |
59.94±4.07* |
| Ferritin (ng/ml) |
54.18±11.53 |
131.46±18.56* |
67.99±11.77 |
131.32±25.27* |
65.78±12.78 |
134.58±21.42* |
130.11±25.79* |
|
| Values are mean ±SD;
* p<0.01. |
| |
| Table 14 represents the values of
iron, TIBC, %transferrin saturation and ferritin
in normal and in AMI patients according to the food
habits and family history of AMI. The values of
iron, %transferrin saturation and ferritin were
found to be significantly increased (p<0.01)
in AMI patients with the habits of vegetarian and
non vegetarian food intake and with and without
the family history of AMI when compared to that
of the normal controls. The value of TIBC was found
to be significantly decreased (p<0.01) in AMI
patients with the habits of vegetarian and non vegetarian
food intake and with and without the family history
of AMI when compared to that of the normal controls.
The comparison between the AMI patients with and
without the family history of AMI have shown significant
value of %transferrin saturation in AMI patients
without the family history of AMI when compared
to that of the AMI patients with the family history
of AMI. However the other parameters did not show
significant alteration between the groups. |
| |
| DISCUSSION |
| |
| The role of micronutrients and trace
elements in the pathogenesis of CAD have been recently
reported, hence studies related to this aspect are
very rare. However the significant role of antioxidant
vitamins such as vitamin E and vitamin C, the two
very important micronutrients in the pathogenesis
of AMI have been described. Vitamin E which provides
protection against endothelial injury have been
associated with atherosclerosis by preserving endothelium
derived nitric oxide (NO) activity15.
Being a chain breaking antioxidant, vitamin E inhibits
or delay arterial thrombogenesis16.
Vitamin C, a water soluble antioxidant vitamin,
have been reported to improve the endothelial function,
thus reducing the risk of CAD. The antioxidant activity
of vitamin C is not restricted to extra cellular
fluids. It is actively transported into cells and
may play a role in the regulation of intracellular
redox state and antioxidant defenses17,
possibly via regulation of intracellular thiol species
such as glutathione. |
| |
| In the present study the values of
vitamin E and vitamin C were found to be decreased
in AMI patients when compared to that of the normal
healthy individuals, indicating the low values of
these vitamins in the serum of AMI patients. Irrespective
of the risk factors the values of these vitamins
were found to be decreased in all the AMI patients
either due to a low supplementation or due to an
impaired metabolism. Further the value of vitamin
C was found to be less in AMI patients with age40mg/dl
when compared to the other age groups. In AMI males
the value of vitamin C was found to be less than
that in AMI females. According to the time of onset
of chest pain the values of vitamin E and vitamin
C were found to be less in patients with time of
onset of chest pain from 12 midnight to 6 am when
compared to that of the other groups. The values
of vitamin E and vitamin C were found to be less
in AMI patients with the history of diabetes and
hypertension, indicating that the values of these
vitamins may be less in diabetic and hypertensive
patients. Further the value of vitamin E was found
to be less in AMI patients the cholesterol value
>200 mg/dl, in patients with non vegetarian food
intake and in patients without the family history
of AMI. Vitamin C was found to be less in patients
with the habit of smoking. All these results together
indicate the impairment of the endothelial function
in these AMI patients due to a reduction in the
amount of these antioxidant vitamins in the body. |
| |
| Zn and Mg, the two essential trace
elements require for the normal functioning of the
body is thought to impair the oxidative injury by
free radicals or ROS18.
Zn is an integral component of various metallo-enzymes
and along with other metals can activate a wide
variety of enzymes. Further Zn functions to stabilize
the membranes, perhaps by decreasing the lipid peroxidation
of these structures. The salutary effect of Zn in
wound healing may be related to the membrane stabilizing
effect. Thus cell damage would be decreased19.
Hypomagnesaemia has been reported in patients with
coronary artery disease20.
Magnesium is an obligatory cofactor in the enzyme
reactions of GSH synthesis and in all biosynthetic
enzyme reactions involving ATP and Mg deficiency
has been reported to inhibit biosynthesis of GSH21.
Further more, Mg deficiency also leads to reduced
levels of endogenous antioxidant defenses (vitamin
E and vitamin C), which may limit free radical detoxification21. |
| |
| In the present study we have observed
the decreased value of Zn and Mg in all the AMI
patients when compared to that of the normal controls,
indicating the deficiency of these trace elements
in AMI thus leading to the more complications of
the disease. The value of Mg was found to be less
in AMI patients with age ranges from 40-60 years
and in AMI males when compared to that of the AMI
females. The value was found to be even less in
patients with the onset of chest pain from 6 am
to 12 noon, in patients with the history of diabetes
and hypertension, patients with a cholesterol value
>200 mg/dl and in patients with the habit of
non vegetarian food intake. The value of Zn was
found to be less in patients with the history of
hypertension and a cholesterol value of >200
mg/dl. These results indicate the impaired values
of Zn and Mg in AMI patients and it could potentiate
the oxidative injury to myocardium by free radicals. |
| |
| The presence of iron in cytochromes,
catalase, hydroxylase, peroxidases, saturases, lipoxygenases
and cyclooxygenases suggest that iron has an important
role in various metabolic events related to lipids,
such as the oxidative degradation of fatty acids
and the synthesis of unsaturated fatty acids, plasminogens
and prostaglandins. However, studies in this area
are limited. Oxidation of LDL-cholesterol is catalyzed
by iron present in atherosclerotic gruel12.
Serum deficient in iron has minimal oxidative capacity
that increases with iron repletion. Several studies
have been conducted in developed countries to assess
the association of iron with coronary heart disease
or AMI. Iron besides promoting lipid peroxidation
could increase the risk of AMI through the elevation
of blood haematocrit and blood hemoglobin levels.
This in turn increases the viscosity of blood and
has a direct thrombogenic effect22.
Ferritin is the storage form of iron and high levels
of ferritin are always associated with CAD23.
The concentration of ferritin in the serum is directly
proportional to the levels of body iron stores.
The body iron status in turn related to the concentration
of the ferritin, its storage form and transferrin,
the transport form. The total iron binding capacity
(TIBC) is also considered to be an indicator to
know the iron status of the body. |
| |
| The results of the present study have
shown increased values of iron, %transferrin saturation
and ferritin in AMI patients when compared to that
of the normal healthy individuals. The TIBC value
was found to be decreased. The value of ferritin
was found to be more in patients with time of onset
of chest pain from 12 noon to 6 pm and the value
of % transferrin saturation was found to be more
in AMI patients with a family history of AMI. However
all the other parameters did not show much alteration
between the groups. So the present study indicates
the increased levels of iron, %transferrin saturation
and decreased values of TIBC in AMI patients. |
| |
| The results of the present study indicate
the deficiency of the micronutrients such as vitamin
E, vitamin C, Zn and Mg in AMI patients and increased
values of iron, %transferrin saturation and ferritin
and decreased values of TIBC in AMI patients compared
to that of the normal controls. These together constitute
the further complications and the severity of AMI
in these patients. |
| |
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