Tobacco and Public Health - TCSC Indonesia

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TOBACCO AND CARDIOVASCULAR DISEASE
Fig. 32.1 (continued).
have contributed to the unprecedented downturn in mortality from IHD that occurred
in the late 1960s and has continued since (Dwyer and Hetzel 1980) (see Fig. 32.2).
However, the same change in the epidemiology of the disease also ‘fits’ with the major
shift from plain to filter cigarettes that occurred from the late 1950s onwards. On the
other hand, neither the change in level of smoking nor the type of cigarette smoked
would explain why mortality from stroke, the more lethal manifestation of CeVD,
began falling in the early 1950s (Jamrozik 1997), unless the time-trend for reduction
of risk, specifically after cessation of smoking, was significantly faster for CeVD than
for IHD. Development of effective pharmacological treatments for high blood pressure
might conceivably have triggered the downturn in mortality from CeVD, even
though hypertension is also a major independent and modifiable risk factor for IHD.
Data on other potentially important factors, such as changes in dietary patterns consequent
on the arrival of significant numbers of migrants from continental Europe
and on developments in kitchen appliances, are extremely scant (Jamrozik et al.
1992), and those on levels of blood lipids and patterns of physical activity virtually
non-existent.
The example of secular trends in mortality from arterial disease in Australia serves to
illustrate several important points. While application of the Bradford Hill criteria to
observational data on individuals itself requires considerable judgement, interpretation