All new patients attending a general surgical
outpatient clinic were studied over three months. There were 606 patients aged over 30
years. In each case the hair was recorded as natural, grey, or balding before a subsequent
detailed history was taken of the use of hair colorants and smoking. Patients using hair
colorants were excluded from the study. Baldness was assessed by reference to the Hamilton
baldness scale(3) and regarded as present on category III or greater. A non-smoker was
defined as someone who smoked fewer than 10 cigarettes or less than 14 g of tobacco a month.
Those who had smoked in the past were counted as smokers.
Of the 268 men and 338 women,
152 of each sex smoked. Initially an overall odds ratio for the association of smoking and
baldness in men, allowing for the relation between baldness and age, was calculated using
the logit method. The odds ratio was 1.93 (95% confidence interval 1.13 to 3.28). Since the
number of bald women was very small (4) no corresponding
calculation was carried out for women. The overall odds ratio for
the relation of grey hair and smoking was then calculated, for both men and women, excluding
bald subjects, allowing for the relation between grey hair colour and age, giving a value of
4.40 (3.24 to 5.96). This indicates a significant relation between grey hair and smoking
(P<0.0001). Since some values in table 1 were 0, the odds ratio was calculated after adding
0.5 to each value.(4) The relation between grey hair and smoking, after excluding bald
subjects, was consistent for all age groups in both sexes.
Comment Aging is a
complex process that affects us all. All organs undergo a series of age related changes in
which the vascular system is prominent. In a detailed study among employees of the
Department of the Environment Bulpitt et al observed that, in men but not women,
smoking was associated with an increase in apparent biological age over chronological
age.(5)
Our observational study suggests a link between smoking and grey hair in
both men and women and between smoking and baldness in men, but it cannot demonstrate a
causal link. Patients attending the clinic may not be representative of the general
population, or there may be other factors that give rise to an association between smoking
and hair changes. Possibly smoking causes severe disease, which in turn causes biological
aging. In a sample of patients attending an outpatient clinic we may get a high proportion
with severe disease, which might lead to an apparent association between smoking and
biological aging. Unfortunately, we omitted to ascertain the number of cigarettes each
smoker smoked per week and therefore a dose response relation could not be calculated.
If
young people can be persuaded that smoking will lead to premature grey hair, and in men to
baldness, this may offer a promising line of approach in health education against smoking.
Funding: None.
Conflict of interest: None.
Leigh Infirmary,
Leigh,
Lancashire WN7 1HS
J G Mosley, consultant
surgeon
Centre for Cancer Epidemiology,
Christie Hospital,
Manchester M20 4QL
A C C Gibbs,
statistician
References:
1 Model D. Smokers face:
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2 Schnohr P, Lange P,
Byboe J, Appleyard M, Jensen G. Grey hair, baldness and wrinkles in relation to myocardial
infarction. Am Heart J 1995;130:1003-10.
3 Lesko SM, Rosenberg L, Shapiro
S. A case control study of baldness in relation to myocardial infarction in men. JAMA
1993;269:998-1003.
4 Armitage P, Berry G. Statistical methods in medical
research. Oxford: Blackwell, 1994:515.
5 Bulpitt C J, Shipley M J, Broughton P M G,
Fletcher A E, Markowe H L J, Marmot M G, et al. The assessment of biological age.
Ageing Clin Exp Res 1994;6:181-91.
