Aims/hypothesis. A reduction of diabetes-related blindness by at least one
third was declared a primary objective for Europe in 1989 (St. Vincent Decl
aration). To ascertain a potential change of incidence rates, we collected
data on blindness in a German district (population: about 5 million) over 9
years.
Methods. We obtained complete lists of newly registered blindness-allowance
recipients between 1990 and 1998 and population data on Wurttemberg-Hohenz
ollern, Germany. We estimated incidence rates of blindness in the general p
opulation and the diabetic population. To ascertain any time trend, we appl
ied Poisson regression models.
Results. There were 6371 newly registered blindness allowance recipients (1
990-1998). Of these 67% were women and 27% had diabetes. Mean age was 71.7
years. Standardised results in the diabetic population (incidence rates per
100 000 person-years; standard: diabetic population; 95% CI): 1990: 72 (61
;82); 1991: 88 (76;100); 1992. 77 (67;88); 1993: 82 (71;93); 1994: 62 (53;7
2); 1995: 82 (71;93); 1996: 70 (60;80); 1997: 69 (59;79); 1998: 59 (49,68).
The Poisson model estimated a 3% decrease of incident blindness in the dia
betic population for each year (Relative risk per year 0.97; CI: 0.95; 0.99
). No significant change could be observed in the non-diabetic population (
Relative risk: 0.99; CI: 0.98; 1.00). Relative risks for each year varied b
etween sub-groups according to sex, diabetic status and cause of blindness
between 0.94 and 1.01.
Conclusion/interpretation. A slight reduction of incident blindness could b
e shown but a reduction by one third has not been reached. Several possible
sources of bias in the data have to be considered.