Two Consequences of Quitting

Quitting seems to have little effect on life-expectancy, as is shown in six of the

seven controlled trials which have been conducted to determine any such effect. The results

of the seventh are more complex.

This was a randomised five-year multifactorial prevention trial of

vascular disease (Miettinen, Huttunen, Naukkarinen et al., 1985). An

intervention group of 612 forty-eight year old businessmen, considered

to be at high risk of cardiovascular disease, were encouraged to

change their diet (particularly with regard to fat intake) to reduce

smoking and to take more exercise. Where blood pressure and serum

lipid levels did not fall sufficiently, the subjects were treated with

a variety of drugs, mainly diuretics and beta-blockers and probucol

and clofibrate. A similar group of 610 men was uncounselled and

untreated except that 15% of them received anti-hypertensive drugs.

After 5 years, most risk factors, including weight, blood pressure,

serum cholesterol and triglycerides and tobacco consumption had

improved significantly in the intervention group compared

with the control group.

At the end of 5 years, total mortality in the intervention group was

10/612 and in the control group 5/610, a non-significant difference.

There were no significant differences in mortality from specific

causes nor in morbidity except for non-fatal stroke which was more

common in the control group (8 versus 0). In brief,

improvement in lifestyle did not reduce CHD deaths or total deaths.

15 years later the story was very different.There were 45% more deaths

in the intervention group than in the control group (67v46). This was

largely due to more than twice as many cardiac deaths but there were

also 13 "violent" deaths compared to 1 in the control group.Quitting

may not have caused this disastrous result but it doesnt appear to

have helped.

There have been just 6 other similar trials, with happier results: no

change in total death rates, deaths due to cancer or deaths due to

cardiovascular disease. Quitting is probably less dangerous than this

Finnish study suggests

But one consequence of quitting, though rare, is well-known and

dangerous, ulcerative colitis. I give the example of a woman who found

that smoking eliminated all sign of the disease. When she tried quitting

the disease recurred.

This case is a clear reminder that people are all different. Quitting is

not good for eveyone and may be seriously harmful.

(Finnish study)

( Ulcerative colitis2)

Installed 7 august 2006.