Incidence of schizophrenia does not vary with economic status of the country: evidence from a systematic review.
BACKGROUND
A recent systematic review found that the prevalence of schizophrenia was lower in developing nations compared to developed nations. However, there is a lack of information about the association between economic status and the incidence of schizophrenia. The aim of this study was to examine the association between economic status and the underlying incidence of schizophrenia based on a recently published systematic review of the incidence of schizophrenia.


METHODS
The analyses were based on 167 discrete incidence rates from 52 studies. Nations were divided into three categories according to per capita gross national product. Based on these categories, we compared the incidence rates for schizophrenia when adjusted for within-study variation.


RESULTS
The median (and 10-90% quantiles) incidence rates per 100,000 persons for Least Developed Countries (three studies), Emerging Economies (nine studies), and Developed Countries (42 studies) were 20.0 (0.4-35.0), 11.0 (5.0-26.0) and 16.0 (8.0-48.0) respectively. There was no significant difference in incidence rates between these groups.


CONCLUSIONS
While there is a lack of information on the incidence of schizophrenia in the developing world, there is no evidence to suggest that the incidence of schizophrenia varies by economic status. In light of the evidence that the prevalence of schizophrenia is higher in developed countries, more research is warranted focused on the interaction between economic measures, and the incidence, prevalence and course of schizophrenia.
Saha
Sukanta
S
Queensland Centre for Mental Health Research The Park Centre for Mental Health, Wacol, QLD, 4076, Australia. sukanta_saha@qcmhr.uq.edu.au
Welham
Joy
J
Chant
David
D
McGrath
John
J
D019049:Developed Countries / Q000706:statistics & numerical data; D003906:Developing Countries / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D015995:Prevalence; D012559:Schizophrenia / Q000191:economics / Q000453:epidemiology*; D012923:Social Class