Sir,
We read with interest Miller's article describing a discrepancy between Chinese rates of suicide and depression (27th January 2006). However, we feel that Miller, by concentrating on fatal self-harm rather than all acts of self-harm, misses an opportunity to understand the discrepancy he notes.
High rates of suicide and low rates of depression are not restricted to China. Many countries of the Asian ‘Suicide Belt’ have suicide rates higher than China.1 For example, community studies from rural India report rates as high as 100/100,000.2
Suicide rates result from the incidence of self-harm and its case fatality. Our research in Sri Lanka indicates that high rates of suicide from self-poisoning are due to a high case fatality rather than a high incidence of self-harm itself.3 A useful contrast can be made with the UK.
Self-poisoning in the UK is very common, with an annual incidence of presentation to hospital of around 300/100,000. However, self-poisoning is rarely lethal, with case fatality normally <0.5%.4 Self-poisoning is also common in Sri Lanka, with an estimated incidence of around 363/100,000 in one rural district. However, the case fatality is significantly higher at ∼7.4% - at least 15 fold higher than the UK.3 The reason for this higher case fatality in Sri Lanka, as in China, is the common use of highly toxic poisons such as pesticides. Sri Lankan self-poisoners do not seem more keen to die - they simply have easier access to pesticides than to the medicines used in the UK.5
The high suicide rate in Sri Lanka, and China, is not due to higher levels of mental illness or rates of self-harm, but to a higher lethality of self-harm acts. Concentrating solely on rates of mental illness in Asia will not explain the high levels of suicide in this region.
References
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