The possible evidence for an epidemiological transition hypothesis for elderly suicides.

BACKGROUND

An epidemiological transition hypothesis has been developed to explain simultaneously wide cross-national variations in elderly suicide rates, trends over time for elderly suicide rates and age-associated trends in suicides rates. This speculative hypothesis suggests that there is a curvilinear (inverted U-shaped curve) relationship between elderly suicide rates and socioeconomic status fitting the quadratic equation y = a + bx - cx2 (where y is the suicide rate, x is the socioeconomic status, and a, b and c are constants).

METHODS

The predicted curvilinear relationship between elderly suicide rates and gross national domestic product (GDP), a measure of socioeconomic status, fitting the above quadratic equation was examined with a curve estimation regression model using data from the World Health Organization.

RESULTS

The relationship between suicide rates in both sexes in the age-bands 65-74 and 75+ years and the GDP was curvilinear (inverted U-shaped curve) and fitted the above quadratic equation, and was statistically significant (at least p<0.05) in all four groups.

CONCLUSIONS

Caution should be exercised in accepting this model of the epidemiological transition hypothesis for elderly suicide rates because it is generated from cross-sectional data using an ecological design. Ideally, this model requires rigorous testing by following selected countries of low socioeconomic status over time as they develop socioeconomically.