NGHIÊN CỨU GÁNH NẶNG KINH TẾ XÃ HỘI ĐỐI VỚI PHƠI NHIỄM THUỐC LÁ CHỦ YẾU VỀ BỆNH TIM MẠCH Ở VÙNG NÔNG THÔN_TÂY NAM TRUNG QUỐC

The economic burden of tobacco
exposure-related major cardiovascular
diseases in rural south- west China
Cai Le, MD, Ph.D.
Professor
School of Public Health
Kunming Medical University


Outline
 Background
 Objective
 Methodology
 Results
 Conclusions


Background
 Cardiovascular

diseases (CVD) are a major
public health concern in the world, accounting
for half of all non-communicable disease
deaths worldwide. China is also experiencing
an epidemic of CVD during recent decades.
 Smoking was an independent risk factor for
CVD, and secondhand smoke (SHS) is also d
emonstrated to be an established cause of C
VD in previous studies.

Background
 As

one of the most costly diseases, CVD
represents a major economic burden on
healthcare systems. However, the literature
on the economic consequences of CVD
associated with tobacco use is still sparse in
China.


Objectives
 The

aim of this study is to use a prevalencebased, disease-specific cost-of-illness
method to estimate the economic burden of
two major components of CVD (coronary
heart disease and stroke) attributable to both
smoking and exposure to SHS in rural
southwest China including direct and indirect
costs.


Methodology


Study area and population






This study was a community-based, cross-sectional
survey conducted in four rural areas of Yunnan
province, China.
Yunnan is located in southwest China and had a
recorded population of 45.9 million people.
Yunnan is a production and consumption hub for
tobacco products, tobacco is cultivated in 45 of the
province’s counties and more than 2.3 million
farmers in the province are engaged in tobacco
cultivation.


Cost components
 The

cost of CVD comprised two components:
direct costs and indirect costs. Direct costs
were further divided into two subcategories:
direct medical costs and direct non-medical
costs.


Data source
 Information

regarding the prevalence,
economic consequences and related aspects

of CHD and stroke, smoking habits, and
exposure to SHS in rural areas of Yunnan
province were obtained from a communitybased cross-sectional health interview and
examination survey.


Sampling technique
A

multi-stage stratified random sampling
method was used to select individuals aged
≥18 years from a total of 44 townships in
Yunnan province.


Multi-stage stratified random sampling
129 Counties in Yunnan Province
Tobacco cultivation areas

Economically
advantaged

Economically
disadvantaged

Non-tobacco cultivation areas

Economically
advantaged

Economically
disadvantaged

All townships (44 townships)
PPS sampling

Village 1

Village 2
SRS sampling

Individuals

Village 3

……


Data collection


Each participant who gave the informed consent was
personally interviewed face-to-face by trained
interviewers, using a pre-tested structured questionnaire.
Information on demographic characteristics, self-reported
smoking habits, annual disease specific inpatients
hospitalization expenditures, expenditures for outpatient
visit and self-medication, direct non-medical costs, and
work absence due to target disease were obtained
through the questionnaire.

Definitions
 CHD

and stroke was identified by selfreported physician diagnosis.
 Smokers were defined as persons who had
smoked at least 100 cigarettes in their
lifetime.
 Exposure to SHS was defined as nonsmokers who reported exposure to
environmental tobacco smoke at home or at
work for a minimum of 15 minutes at least
one day per week.


Calculation of Population Attributable
Fraction (PAF)

P (OR  1)
PAF 
100%
P (OR  1)  1
Where: P denotes to the prevalence of
smoking or exposure to SHS in a given
population, and OR denotes odds ratio for
disease-specific morbidity caused by
smoking or exposure to SHS.


Calculation of direct costs

 The

costs associated with outpatient/inpatient
visits were estimated by multiplying the
number of outpatient visits/inpatient hospital
admissions related to CVD by the
outpatient/inpatient unit costs per year.


Calculation of indirect costs
 Indirect

costs were estimated as the earnings
lost as a result of CVD-related morbidity
using the “human capital” approach.


Statistical analysis
 Descriptive

analysis techniques and
multivariate logistic regression were used in
this study. All data analyses were conducted
with R2.9.2 software


Results


Demographic characteristics of

the study population


A total of 18,000 individuals
aged ≥18 years were asked
to participate in this study.
Of these, 17,158 agreed to
participate (response rate =
95.3%).

Participants in the study
included 8,156 males and
9,002 females.



Prevalence of smoking, SHS ,
and CVD
 The

overall prevalence of smoking and
exposure to SHS in the study population was
35.5% and 42.2, respectively.
 The overall prevalence of stroke and CHD
was 1.0% and 1.7% among the surveyed
population, respectively.


OR and PAF% of major cardiovascular
diseases associated with smoking and SHS

Secondhand smoke exposure
(SHS)

Smoking
Variables

Multivariable
adjusted OR †
(95% CI)

PAF(%)

Multivariable
adjusted OR †
(95% CI)

PAF(%)

Male

2.42** (1.28, 4.58)

50.93

2.32** (1.26, 4.25)

33.98

Female

4.01* (1.38, 11.68)

3.77

1.92** (1.18, 3.11)

28.39

All

2.46** (1.67, 3.64)

34.14

2.04** (1.39, 2.97)

30.50

Male

8.32** (3.88, 17.87)

84.25

3.54** (2.14, 5.87)

49.76

Female

4.27** (1.85, 9.84)

4.08

1.60** (1.14, 2.23)

20.55

All

5.34** (3.15, 9.03)

60.64

1.94** (1.45, 2.59)

28.40

Stroke

CHD


OR and PAF% of major cardiovascular
diseases associated with smoking and SHS
 There

were significant positive associations
between smoking, exposure to SHS and risk
for stroke and CVD for both sexes.

Cost of illness of major cardiovascular
diseases (in US$) in rural southwest China
Stroke

Coronary heart disease

Unit cost

Total
(million)

Unit cost

Male

Female

All

Total
(million
)

Direct medical
costs

1238.0

1565.0

1406.8

8.71

2324.6

1331.7

1738.0

16.16

Outpatient visits

13.70

35.6

26.2

0.16

42.3

30.62

34.5

0.32

Hospitalization

1048.3

1292.0

1171.9

7.26

1928.4

1052.5

1415.2

13.16

Self-medication

176.04

237.42

208.7

1.29

353.8

248.6

288.3

2.68

Direct non-medical
costs

19.43

102.21

60.03

0.37

31.9

59.3

48.6

0.45

Total direct costs

1257.4

1667.2

1466.8

9.08

2356.5

1391.1

1786.6

16.61

9.82

23.12

19.3

0.12

14.5

39.1

31.2

0.29

1267.2

1690.4

1486.2

9.2

2371.0

1430.2

1817.9

16.9

Cost components

Total indirect costs
Total cost of
illness

Male

Femal
e

All

Cost of illness of major cardiovascular
diseases (in US$) in rural southwest China

Males had higher unit costs of illness due to
CHD than females, whereas unit costs of
illness due to stroke were higher in females
than in males (P<0.05).
 Inpatient hospitalizations represented the
main component of direct costs of CVD, and
direct costs were the main drivers of the
economic burden of CVD.



Cost of CVD attributable to smoking
and exposure to SHS
Variables

Costs of illness attributable to
smoking
(million)

Costs of illness attributable to
secondhand smoke exposure
(million)

Direct
costs

Indirect
costs

Total cost of
illness

Direct
costs

Indirect
costs

Total cost of
illness

Male

3.97

0.31

4.28

2.65

0.21

2.86

Female

0.37

0.05

0.42

2.77

0.38

3.15

All

4.34

0.36

4.70

5.42

0.59

6.01

Male

15.55

0.01

15.56

10.9

0.07

10.97

Female

0.03

0.002

0.03

3.18

0.09

3.27

All

15.58

0.01

15.59

14.08

0.16

14.24

Stroke

CHD