In 1997, the South African death notification form was revised to include questions on the smoking status of the deceased. This study used 481,640 notifications of deaths occurring between 1999 and 2007 to assess smoking-attributed mortality in South Africa. Methods: A case-control proportional mortality design was used to estimate smoking-associated relative risks and attributable fractions for a number of potentially smoking-related causes of death. Cases: deaths from underlying causes known from other studies to be causally associated with smoking. Controls: deaths from medical conditions expected to be largely unrelated to smoking. The attributable fractions were then used to calculate the annual average number of deaths attributable to smoking in South Africa.

1. Tobacco-attributed mortality from
a question on smoking on the
South African Death Certificate.
Acknowledgements
We are grateful to the thousands of doctors and funeral undertakers who completed the information
on smoking on the death notification forms, and to the millions of next of kin who willingly provided it.
The Ministry of Health, led by Hon Dr N Dlamini-Zuma, approved the revised death notification form.
Background
In 1997, the South African death notification form was revised to include questions on the smoking status of the deceased. We used
481,640 notifications of deaths occuring between 1999 and 2007 to assess smoking-attributed mortality in South Africa.
Methods
A case-control proportional mortality design was used to estimate smoking-associated relative risks and attributable fractions for a
number of potentially smoking-related causes of death. Cases: deaths from underlying causes known from other studies to be causally
associated with smoking. Controls: deaths from medical conditions expected to be largely unrelated to smoking. The attributable
fractions were then used to calculate the annual average number of deaths attributable to smoking in South Africa.
Results
During 1999 to 2007 the four
major smoking-attributed
causes of death aged 35-74 in
South Africa were tuberculosis;
ischaemic heart disease; lung
cancer and chronic obstructive
pulmonary disease; with 3438,
3187, 2882 and 2610 smoking-
attributed deaths per year
respectively. The smoker vs. non-
smoker relative risks of death
from lung cancer were higher
than for all other causes of death
for both males and females
(3.58 and 4.20 respectively).
Relative risks of death from any
cause were similar for males and
females (1.18 for male smokers
vs. 1.21 for female smokers).
Overall, smoking was responsible
for 16,794 deaths per year or
about 6% of all deaths aged 35-
74 years.
For both males and females, the
proportions of deaths attributable
to smoking were highest in the
coloured population (23.6%
males, 14.1% females) followed
by the white population (14.0%
males, 11.8% females). The
corresponding proportions in the
black population were relatively
low (5.7% males, 1.4% females).
Given that blacks comprise
about 80% of the South African
population, considerable
increases in tobacco attributed
mortality will occur in South
Africa if smoking behaviour
amongst blacks becomes
more like that of their coloured
counterparts.
Conclusions
Adding questions on smoking on the death notification form is a
cost effective and accurate way to monitor smoking attributed mortality.
Debbie Bradshaw1
, Sam Egger2
Pam Groenewald1
, Ria Laubscher3
, Danuta Kielkowski4
, Richard Peto5
, Freddy Sitas2
1. Burden of Disease Research Unit, South African Medical Research Council, Johannesburg 2.Cancer Council NSW, Sydney 3. Biostatistics Unit, South
African Medical Research Council, Cape Town 4.National Institute for Occupational Health, Cape Town 5.Clinical Trials Services Unit, Oxford University
* A smoker was defined as someone who “smoked on most days”
Case-control analysis of 481,640 deaths at ages 35-74 years
^
Attributable deaths/total deaths (nationwide annual averages for deaths aged 35-74)
5.7% (7073/123828)^
23.6% (2663/11284)^
14.0% (2246/16085)^
13.3% (827/6208)^
0510152025
%deathsattributabletosmoking
Black
Coloured
White
Other
Population group
Black Coloured White Other
%deathsattributabletosmoking
5
20
15
10
25
0
Population Group
23.6% (2663/11284)^
14.0% (2246/16085)^
13.3% (827/6208)^
5.7% (7073/123828)^
1.4% (1361/98730)^
14.1% (1318/9366)^
11.8% (1231/10419)^
1.6% (75/4562)^
0510152025
%deathsattributabletosmoking
Black
Coloured
White
Other
Population group
Black Coloured White Other
%deathsattributabletosmoking
5
20
15
10
25
0
Population Group
14.1% (1318/9366)^
11.8% (1231/10419)^
1.6% (75/4562)^
1.4% (1361/98730)^
Cause of death
Male
RR
adjusted*
Female
RR
adjusted*
RR
adjusted*
Attrib.
fraction
%
smokers Deaths
Smoking
attrib.
deaths
Case causes:
Tuberculosis 1.43 1.56 1.45 (1.42-1.47) 13.9 45.0 24794 3438
Chronic obstructive pulmonary disease 2.09 2.83 2.22 (2.16,2.29) 29.6 53.9 8815 2610
Other respiratory 1.34 1.34 1.34 (1.31,1.37) 9.0 35.7 5008 451
Ischaemic heart disease 1.49 1.71 1.54 (1.49,1.59) 15.0 42.9 21317 3187
Stroke 1.17 1.19 1.17 (1.14,1.20) 4.3 29.3 31784 1374
Other cardiovascular 1.25 1.30 1.27 (1.23,1.30) 6.7 31.9 3129 210
Lung cancer 3.58 4.20 3.72 (3.52,3.93) 49.6 67.8 5811 2882
Upper aerodigestive cancer 2.73 2.38 2.66 (2.53,2.80) 35.8 57.3 5716 2044
Stomach, liver, pancreas cancer 1.40 1.35 1.39 (1.31,1.46) 11.4 40.8 4936 562
Female genital/urinary cancer, myeloid leukaemia 1.07 1.20 1.16 (1.09,1.24) 3.1 22.5 4834 152
Parkinson’s, Crohn’s and endometrial cancer 0.44 0.67 0.62 (0.49,0.79) -32.6 14.3 356 -116
Control causes^ 1.00 1.00 1.00 0.0 30.6 73267 0
Cirrhosis^ - - - 0.0 48.0 3716 0
Mental and behavioural disorders^ - - - 0.0 49.0 894 0
HIV related disease^ - - - 0.0 39.5 63007 0
External^ - - - 0.0 46.5 23098 0
Total (all causes): 1.18 1.21 1.18 (1.17,1.20) 6.0 38.4 280482 16794
Black 1.12 1.11 1.12 (1.11,1.14) 3.8 35.3 222558 8434
Coloured 1.45 1.36 1.42 (1.38,153) 19.3 65.6 20650 3981
White 1.40 1.53 1.44 (1.34,1.46) 13.1 43.1 26504 3477
Other 1.29 1.19 1.28 (1.21,1.38) 8.4 38.8 10770 902
* Relative risks adjusted for age, province of death, year of death, education, marital status, sex and population group where appropriate
^ Attributable fractions and RRs were set by definition to zero and one respectively for deaths from control causes, cirrhosis, mental and behavioural
disorders, HIV-related disease and external causes.
Both sexes
Males Females
Nationwide annual
averages
Excluded
causes