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Serum cholesterol, haemorrhagic stroke, ischaemic stroke, and myocardial infarction: Korean national health system prospective cohort study

BMJ 2006; 333 doi: https://doi.org/10.1136/bmj.38855.610324.80 (Published 29 June 2006) Cite this as: BMJ 2006;333:22

The Japanese comparison

Yet again, a potential relationship between low cholesterol levels
and haemorrhagic stroke is dismissed. Yet again, a causal relationship
between high cholesterol levels, ischaemic stroke and CHD is (apparently)
confirmed.

Yet data from Japan directly contradicts their conclusions. From 1958
to 1995 fat consumption increased from 5% to 20% of the total daily energy
consumption, and cholesterol levels rose from 3.9mmol/l to 5.0mmol/l (1).
During this period the rate of stroke (combined) fell from
1344/100,000/year to 205/100,000/year. (Age group 60 - 69). This is a 6.5
fold reduction in the rate of stroke (2). (There was also a decrease in
death rate from CHD)

The possiblity that increased fat consumption was the causal factor
in reducing the rate of stroke is strongly supported by a study in Stroke
(3), which concluded that: 'A high consumption of animal fat and
cholesterol was associated with a reduced risk of cerebral infarction
death.'

The fact is that a low cholesterol level has been found to be
associated with an increased risk of haemorrhagic stroke in many different
studies. And when cholesterol levels rose dramatically in Japan the rate
of stroke fell off the side of a cliff.

A low cholesterol level may well be a 'causal' risk factor for
haemorrhagic stroke, and the connection cannot be dismissed by this study.

1:Adachi H, Hino A. Trends in nutritional intake and serum
cholesterol levels over 40 years in Tanushimaru, Japanese men. J
Epidemiol. 2005 May;15(3):85-9.

2: Longjian Liu, MD, MSc, PhD; Katsumi Ikeda, PhD Yukio Yamori, MD,
PhD 'Changes in Stroke Mortality Rates for 1950 to 1997. A Great Slowdown
of Decline Trend in Japan.'Stroke. 2001;32:1745

3: Catherine Sauvaget, Jun Nagano, Mikiko Hayashi, Michiko Yamada.
'Animal Protein, Animal Fat, and Cholesterol Intakes and the Risk fo
Cerebral Infarction Mortality in the Adult Health Study.' Stroke
2004;35:1351.

Competing interests:
I am a member of the international network of cholesterol skeptics (THINCS)

Competing interests: No competing interests

09 June 2006
Malcolm E Kendrick
General Practitioner
Benchill Medical Centre, 127 Woodhouse Lane, Wythenshawe M22 7WP