a1 Ageing, Ethnicity and Mental Health, University of Central Lancashire, Preston, U.K. and West London Mental Health NHS Trust, London, U.K.
Background: Elderly suicide rates are associated with the elderly population size, the proportion of elderly in the general population and the elderly dependency ratio.
Methods: A cross-national study examining the “a priori” hypothesis that the relationship between elderly suicide rates and average annual population growth rates would be curvilinear (U-shaped curve) fitting the quadratic equation y = a + bx + cx2 (where y is the elderly suicide rate, x is the population growth rate and a, b and c are constants) was conducted using data from the World Health Organization and the United Nations.
Results: There was a significant curvilinear (U-shaped curve) relationship between elderly suicide rates and average annual population growth rates fitting the above quadratic equation.
Conclusions: A theoretical model with three sequential stages incorporating population growth, the elderly population size, the proportion of elderly in the general population, life expectancy and birth rates was proposed to explain the findings. Caution should be exercised in the application of this model because of the cross-sectional and ecological study design whereby the findings are subject to ecological fallacy and require rigourous testing in within-country longitudinal studies over time.
(Received June 30 2008)
(Revised July 30 2008)
(Revised July 31 2008)
(Accepted August 04 2008)
(Online publication November 25 2008)
c1 Correspondence should be addressed to: Professor Ajit Shah, Consultant Psychiatrist, West London Mental Health NHS Trust, Uxbridge Road, Southall, Middlesex, UB1 3EU, U.K. Phone: +44 208 354 8140; Fax: +44 208 354 8898. Email: firstname.lastname@example.org.