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ABSTRACT
The present study is an attempt to investigate
the mortality rates by age, sex and different
categories of diseases. The diseases are categorized
as Micro-organism
(C1), Un-natural (C2),
Physiological disorder (C3)
and Other (C4). and also
as Endogenous ( ),
Exogenous ( )
and other ( )
and depending on age, the stages of life are categorized
as Infant (<1 year), Children (1-4 years),Youth
age group (5-19 years), Most productive age group
(20-44 years), Older productive age group (45-64
years) and Old age group (65+ years ).The analysis
shows that child and old age death rates are still
high in Matlab particularly due to causes of micro-organism
(C1)
and exogenous ().
Key Words: Mortality Rate, Diseases, Endogenous,
Exogenous, Productive Age
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INTRODUCTION
Cause-specific mortality statistics
are primary evidence for health policy formulation,
programme evaluation, and epidemiological research (Seval
Akgün et al., 2007). Study of the trends in mortality
by causes of death in Bangladesh is scarce due to paucity
of relevant data.
Data on mortality by age, sex
and cause are primary inputs for assessing population
health status, and a cornerstone of the evidence base
for health policy, in combination with other epidemiological
and socio-economic information. While medically certified
cause of death data from complete civil registration
systems is the 'gold standard' for such statistics,
these are generally not available in over two-thirds
of all countries (Mathers et al., 2005). Currently,
several critical mortality indicators (e.g. infant,
child and maternal mortality rates) are estimated using
data from demographic surveys.
While trends in these indicators
do suggest improvements in maternal and child health
over the past three decades, they are prone to measurement
error, due to sampling as well as recall bias. Even
if the levels and trends were reliably estimated, further
improvements in population health would require accurate
information on cause-specific mortality to guide policy
and programme priorities (Ruzicka et al., 1990).
Persons dying of different causes
are not recorded on a national basis therefore it is
very difficult to obtain cause-specific death statistics
for the population of the country. Death statistics
by various causes are recorded, perhaps only for Matlab
population under the Demographic Surveillance System
(DSS) undertaken by ICDDR, B.
The present study was carried
out with an objective of investigating the trend in
the level of mortality by various types of causes of
death and stages of life, in the population of Matlab,
a rural population of the country.
DATA AND METHODOLOGY
The present study has utilized
published data on mortality of Matlab population in
Chandpur district, Bangladesh. The Scientific Reports
of ICDDR,B publish statistics on births, deaths, migration
and marriage of the DSS, Matlab. The mortality data
are published by age and sex and also by causes of death.
Our present study uses causes-specific, age and sex
data from the years 1980 and 1987. Such data are available
in the Scientific Report No.70 published in 1992 (ICDDR,
B 1992). Quite a good number of causes of death (in
terms of disease) prevail in Bangladesh as well as in
Matlab. The Scientific Reports of DSS of the year 1980
recorded 27 diseases, and 21 diseases in 1987. For the
sake of analysis the age groups are classified on the
basis of Spengler and Duncan (1963) classification which
we call stages of life. These are as follows:
Under 1 (one) year: Infant
1-4 years: Children
5-19 years: Youth age group
20-44 years: Most productive age group
45-64 years: Older productive age group
65+ years: Old age
However, such a classification
of life cycle is arbitrary but we believe that prevalence
of disease and incidence of death due to various diseases
can well be represented by such a classification of
life stages.
The causes of death are grouped into the following categories
with the relevant disease.
Category I: Micro-organism
(Labelled as C1):
Measles, tetanus, diarrhoea (acute, chronic), dysentery
(acute, chronic), jaundice, tuberculosis, venereal disease,
cholera (proved), rheumatism, ENT disease other infectious
disease, ARI (pneumonia, influenza), etc.
Category II: Unnatural
Death (Labelled as C2):
Drowning, murder, suicide, homicide, accident etc.
Category III: Physiological
Disorder (Labelled as C3):
Disease of GI tract, respiratory, malignant neoplasms,
COPD, gastrointestinal, dropsy, vascular (heart and
liver) disease senility (old diseases ) etc.
Category IV: Other (labelled
as C4):
Skin disease, childbirth (direct obstetric), nutritional,
fever (all forms), unknown and other.
In analyzing mortality in terms
of cause of death in detail it is useful to distinguish
the broad classes of disease designated as endogenous
and exogenous (Siegel and Sryock, 1976). Thus on the
basis of our data and nature of diseases the total causes
are again categorized into three categories. They are
as follows with the relevant disease:
Category I: Endogenous
(Labelled as ):
Malignant neoplasms (cancer), disease of G.I. tract,
cardiovascular (heart & liver) diseases, gastrointestinal,
childbirth (direct obstetric), skin disease, dropsy,
rheumatism, senility (old age), COPD (Chronic, Obstructive,
Pulmonary Disease ).
Category II: Endogenous
(Labelled as ):
Diarrhoea (acute, chronic), dysentery (acute, chronic),
tuberculosis, tetanus, measles, venereal disease, drowning,
murder, suicide, homicide, accident, cholera (proved),
jaundice, respiratory, fever (all forms), ENT disease,
other infectious and ARI (pneumonia, influenza), etc.
Category III: Other (Labelled
as ):
Nutritional, unknown and other.
The analysis is performed following
the stages of life and various categories of disease
as described above.
In order to get a clearer picture
of the prevalence of mortality due to various categories
of diseases at different stages of life, we need to
compute the cause and life stage specific mortality
rates for the study population. Such rates are computed
(Johnson.et al.,1980) in the following way,
Mis = (Dis
/ Ps) x 1000
Where Mis is the observed mortality rate
due to i'th category of disease at the stages of life
S. Here Dis denotes observed deaths due to
i'th category of disease at the Sth stage of life out
of the exposure population Ps in that stage of life.
For infant stage,
Mis = (Dis
/ B) x 1000
Where B is the total births
born alive and S indicates the infant stage of life.
RESULTS
Table 1 presents the mortality
rates due to various categories of diseases viz, C1(micro-organism
), C2(unnatural
death), C3(Physiological
disorder) and C4(other
) and also for all causes (C) at different stages of
life as indicated in the table for males and females
of Matlab DSS population for the years 1980 and 1987.
The data shows that infant mortality
rates (IMR) due to all causes (C) for male, female and
both sexes respectively are 90.3, 118.5 and 103.9 per
1000 live births in 1980 whereas the respective figures
are 90.3, 83.1 and 86.7 in 1987. Marked difference is
evident in male-female IMR in both the year of 1980
and 1987 with a sharp decline in female IMR in 1987.
Except that of child stage of life mortality rates due
to all disease, all other stages have not shown any
virtual temporal variation. Table 1 further shows high
infant mortality rate is due to category C1(micro-organism
) and is 59.8 in 1980 and 79.0 in 1987 followed by cause
C4
(other) which is 23.4 in 1980 and 9.4 in 1987. It is
also found that rates of male death have increased in
1987 in comparison to micro-organism and unnatural causes
in 1980, but the female infants death rates have declined
in 1987 with respect to all categories of disease except
the cause of unnatural death.
The infant female mortality
rates in 1980 are 69.4, 1.7, 9.8 and 37.6 due to categories
of C1, C2, C3
and C4 respectively. Whereas the corresponding
figures in 1987 are 67.7, 2.8, 8 and 1.8 respectively.
The child mortality rates decline in 1987 compared to
1980 due to all categories of causes, except cause C2
(unnatural cause of death ) for male, female and both
sexes.
Table 1. Mortality
Rates due to Group One Categories of Diseases at Different
Stages of Life: Mis; i=1, 2, 3, 4. [Matlab population,1980
and 1987]
|
Mortality rates per 1000(Mis) |
|
Stages life |
Sex |
All causes(C) |
1st cause
C1 |
2nd cause
C2 |
3rd cause
C3 |
4th cause
C2 |
| |
1980 |
1987 |
1980 |
1987 |
1980 |
1987 |
1980 |
1987 |
1980 |
1987 |
|
Infant
<1
|
Male |
90.3 |
90.3 |
58.9 |
79.0 |
0.0 |
1.4 |
7.9 |
0.6 |
23.4 |
9.4 |
|
Female |
118.5 |
83.1 |
69.4 |
67.7 |
1.8 |
2.8 |
9.8 |
0.8 |
37.6 |
11.8 |
|
Both |
103.9 |
86.7 |
64.0 |
73.4 |
0.8 |
2.1 |
8.8 |
0.7 |
30.3 |
10.6 |
|
Child
1-4
|
Male |
16.5 |
8.7 |
6.2 |
5.3 |
2.5 |
2.3 |
2.5 |
0.1 |
5.4 |
1.1 |
|
Female |
28.0 |
16.7 |
14.2 |
11.8 |
2.1 |
2.5 |
5.4 |
0.5 |
6.4 |
1.9 |
|
Both |
22.1 |
12.6 |
10.1 |
8.4 |
2.3 |
2.4 |
3.9 |
0.3 |
5.9 |
1.5 |
|
Youth
5-19
|
Male |
1.6 |
1.5 |
0.7 |
0.5 |
0.2 |
0.4 |
0.2 |
0.2 |
0.6 |
0.7 |
|
Female |
2.2 |
1.7 |
0.8 |
0.5 |
0.1 |
0.1 |
0.4 |
0.1 |
0.9 |
0.9 |
|
Both |
1.9 |
1.6 |
0.7 |
0.5 |
0.2 |
0.3 |
0.3 |
0.1 |
0.7 |
0.7 |
|
Most Productive
20-44
|
Male |
2.9 |
1.7 |
0.5 |
0.3 |
0.2 |
0.4 |
1.2 |
0.3 |
0.9 |
0.7 |
|
Female |
2.9 |
3.0 |
0.7 |
0.3 |
0.1 |
0.3 |
0.8 |
0.5 |
1.4 |
1.9 |
|
Both |
2.9 |
2.4 |
0.6 |
0.3 |
0.1 |
0.3 |
1.0 |
0.4 |
1.2 |
1.3 |
|
Older Productive
45-64
|
Male |
14.5 |
16.0 |
2.9 |
2.1 |
0.5 |
0.6 |
6.8 |
6.3 |
4.7 |
7.0 |
|
Female |
13.2 |
10.4 |
3.7 |
1.9 |
0.0 |
0.1 |
5.4 |
4.8 |
4.1 |
3.6 |
|
Both |
14.0 |
13.2 |
3.3 |
2.0 |
0.3 |
0.3 |
6.1 |
5.5 |
4.4 |
5.3 |
Old age
65+ |
Male |
69.8 |
75.6 |
18.9 |
6.9 |
1.1 |
0.8 |
36.7 |
61.5 |
13.1 |
6.4 |
|
Female |
75.0 |
72.6 |
17.4 |
7.2 |
1.3 |
0.6 |
42.2 |
54.2 |
14.2 |
6.6 |
|
Both |
72.1 |
74.2 |
18.2 |
7.1 |
1.2 |
0.7 |
39.2 |
60.0 |
13.6 |
6.5 |
|
Total |
Male |
12.1 |
10.2 |
4.8 |
4.8 |
0.6 |
0.7 |
3.4 |
3.3 |
3.3 |
1.9 |
|
Female |
14.1 |
10.3 |
6.1 |
4.6 |
0.4 |
0.6 |
3.6 |
2.8 |
4.1 |
2.3 |
|
Both |
13.1 |
10.2 |
5.4 |
4.5 |
0.5 |
0.6 |
3.5 |
3.0 |
3.7 |
2.1 |
The child mortality rates
are 6.2, 14.2 and 10.1 for male, female and both sexes
respectively due to micro-organism cause in 1980. Such
rates in 1987 are 5.3, 11.8 and 8.4 respectively. The
corresponding figures due to causes of unnatural death
are 2.5, 2.1 and 2.3 in 1980 and 2.3, 2.5 and 2.4 in 1987.
For cause physiological disorder (C3) the respective results
are 2.5, 5.4 and 3.9 in 1980 and 4.1, 0.5 and 0.3 in 1987.
It has also been found from Table 1 that female child
mortality rate due to every category of diseases are higher
than male child mortality rates in both the years 1980
and 1987. The highest male child mortality is 6.2 in 1980
due to cause C1 and 5.3 in 1987 due to the same cause
C1 and the lowest figure are 2.5 in 1980 and 0.1 in 1987
both due to cause C3. The highest female child mortality
rate is 14.2 in 1980 and 11.8 in 1987 for cause C1.
From Table 1 it has been found
that mortality rates in youth and most productive age
groups by sex, have declined slightly in1987 from 1980,
due to all categories of disease except category C2.
Mortality rates for both stages of life are slightly
increased in 1987 than in 1980 for female and both sexes
for the causes C2. The youth male mortality rate is
higher due to cause C1 than all other causes in 1980
whereas that in 1987 was due to cause C4. On the other
hand the highest youth female mortality rate is 0.9
in 1987 due to cause C4. The highest male rate of most
productive age group is 1.2 in 1980 due to cause C3
and 0.9 in 1987 due to cause C4. and the highest female
rate of most productive age group is 1.4 in 1980 and
1.9 in 1987 due to other causes.
In oldest productive age group
and oldest age group the male mortality rates are 14.5
and 69.8 respectively due to all causes in 1980 and
the corresponding figures are 16.0 and 75.6 in 1987.Thus
the male mortality rates of oldest productive and old
age groups have increased in 1987 in comparison to 1980.
However for females the corresponding mortality rates
are 13.16 and 72.1 in 1980 and 13.2 and 74.2 in 1987
for both sexes. All other categories also show the same
trend except cause C2 for oldest productive age and
cause C3 of old age group .The oldest productive death
rates due to causes C2 are approximately the same in
1980 and 1987, and older death rates for female and
both sexes have decreased at all categories of causes,
except category C2 in 1987 compared to 1980.
The overall death rates are
12.1, 14.1 and 13.1 of male, female and both sexes respectively
in 1980 and the corresponding figures in 1987 are 10.2,
10.3 and 10.2 implying the death rates have declined
in 1987 compared to 1980.
Mortality rate due to endogenous
, exogenous and other categories of disease of group
two at different stages of life for males, females and
both sexes together for the years 1980 and 1987, are
presented in Table 2.
It is found from this Table
that the infant mortality rates of male, female and
both sexes are 3.2, 3.9 and 3.5 respectively in 1980
and 0.6, 0.8 and 0.7 in 1987 indicating a declining
tendency over time. No sex differential in IMR due to
endogenous cause is apparent. In cases of exogenous
cause the male IMR has increased from 69.5 in 1980 to
80.4 in 1987. The female IMR has shown the reverse trend;
it has decreased from 86.7 in 1980 to 70.5 in 1987.
Infant mortality rates due to exogenous causes for both
the sexes are higher than that of endogenous causes
and other causes . Such a trend is apparent in both
the years.
Child mortality rates due to
both the sexes and different categories Ci
(i=1, 2, 3) of diseases of group two are higher in 1980
than in 1987 .Child mortality rates for different categories
are higher for females than that for males for both
the years 1980 and 1987.
Table
2. Mortality Rates ( is;
i=1,2,3) due to group two categories of diseases
( i;
i=1,2,3) at indicated stages of life: Matlab population,
1980 and 1987
|
Mortality
Rates Per 1000
|
|
Stages of life |
Sex |
Endogenous
cause |
Exogenous
causes |
Other
causes |
| 1980 |
1987 |
1980 |
1987 |
1980 |
1987 |
|
Infant
<1
|
Male |
3.2 |
0.6 |
69.4 |
17.6 |
9.4 |
9.4 |
|
Female |
3.9 |
0.8 |
86.7 |
27.9 |
11.8 |
11.8 |
|
Both |
3.5 |
0.7 |
77.8 |
22.6 |
10.2 |
10.2 |
|
Child
1-4
|
Male |
1.6 |
0.1 |
12.7 |
2.3 |
1.1 |
1.1 |
|
Female |
4.0 |
0.5 |
20.8 |
3.2 |
1.9 |
1.9 |
|
Both |
2.8 |
0.3 |
16.6 |
2.7 |
1.5 |
1.5 |
|
Youth
5-19
|
Male |
0.2 |
0.2 |
1.1 |
0.3 |
0.4 |
0.4 |
|
Female |
0.5 |
0.2 |
1.3 |
0.4 |
0.8 |
0.8 |
|
Both |
0.4 |
0.2 |
1.2 |
0.4 |
0.6 |
0.6 |
|
Most Productive
20-44
|
Male |
1.1 |
0.3 |
1.1 |
0.7 |
0.7 |
0.7 |
|
Female |
1.0 |
1.0 |
1.3 |
0.7 |
1.4 |
1.5 |
|
Both |
1.0 |
0.7 |
1.2 |
0.7 |
1.1 |
1.1 |
|
Older Productive
45-64
|
Male |
5.3 |
6.3 |
7.0 |
2.5 |
7.0 |
7.0 |
|
Female |
5.4 |
4.8 |
5.7 |
2.1 |
3.6 |
3.6 |
|
Both |
5.3 |
5.5 |
6.4 |
2.3 |
5.3 |
5.3 |
|
Old age
65+
|
Male |
35.4 |
61.5 |
26.1 |
8.3 |
6.4 |
6.4 |
|
Female |
43.4 |
58.2 |
24.8 |
6.8 |
6.6 |
6.6 |
|
Both |
39.0 |
60.0 |
25.5 |
7.6 |
6.5 |
6.5 |
|
Total
|
Male |
2.8 |
3.3 |
7.2 |
2.1 |
1.9 |
1.9 |
|
Female |
3.3 |
3.0 |
8.4 |
2.3 |
2.1 |
2.1 |
|
Both |
3.1 |
3.1 |
7.8 |
2.2 |
2.0 |
2.0 |
Youth and most productive mortality
rates for male, female and both sexes for all of categories
of diseases remain almost the same but with a slightly
decline tendency in 1987 compared to 1980. Mortality
rates at the oldest productive, and old age groups,
have shown an increasing tendency for causes categorized
as endogenous (C1)
and, group other a decline tendency over time for cause
exogenous (C2).
The phenomena are evident in both the sexes.
Thus our impression is that
the diseases categorized as exogenous are more prominent
in Matlab in comparison to diseases categorized as endogenous
and others, at least at the infant, and old stages of
life. Children of 1 to 4 years of age also die in good
numbers due to this exogenous cause. However, decreasing
trends in death rates by cause is apparent in almost
all stages of life.
CONCLUSSIONS
Of all causes of death that
prevail in Matlab deaths due to the cause of micro-organisms
are substantial compared to other categories of diseases
at least among the infants and children. This is also
the case in the exogenous category of diseases. Both
the categories consist of mostly communicable and water-borne
diseases. Prevention and control of such disease largely
depends on the improvement of health and sanitation
conditions. Temporal trend in the level of mortality
by various categories of diseases and at different stages
of life cycle reflects a somewhat improved health care
system in Matlab. The impression is that much care still
needs to be taken for further improvement of the environment
condition related to health in this area in particular,
and in the country, in general .
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