Declining incidence of severe retinopathy and persisting decrease of nephropathy in an unselected population of Type 1 diabetes-the Linköping Diabetes Complications Study.
OBJECTIVE
In a previous study conducted over the last decades we found a decreased incidence of nephropathy but unchanged incidence of severe retinopathy among patients with Type 1 diabetes diagnosed in childhood and with 20 years duration of diabetes. The aim of our current study was to investigate the incidence 5 to 10 years later in the same population.


METHODS
We studied all 269 patients in whom Type 1 diabetes was diagnosed in childhood between 1961 and 1985 in a district in southeastern Sweden. Ninety-one percent were monitored for retinopathy until at least 1997 and 95% were monitored for nephropathy. Severe retinopathy was defined as laser-treated retinopathy and nephropathy as persistent proteinuria. Survival analysis was used and the patients divided into five cohorts according to the time of onset of diabetes.


RESULTS
The cumulative proportion of severe retinopathy had declined ( p=0.006). After 25 years it was 47% (95% CI 34-61), 28% (15-40) and 24% (12-36) in the cohorts 1961 to 1965, 1966 to 1970 and 1971 to 1975 respectively. After 30 years it was 53% (40-66) and 44% (28-59) in the oldest cohorts. The cumulative proportion of nephropathy after 25 years duration was 30% (18-42), 8% (1-16) and 13% (4-23) in the cohorts 1961 to 1965, 1966 to 1970 and 1971 to 1975 respectively. After 30 years, it was 32% (20-44) and 11% (2-20) for the oldest cohorts ( p<0.0001).


CONCLUSIONS
In an unselected population with Type 1 diabetes diagnosed in childhood, modern diabetes care markedly reduced the incidence of severe retinopathy and nephropathy.
Nordwall
M
M
Division of Paediatrics and Diabetes Research Centre, Department of Molecular and Clinical Medicine, University Hospital, Linköping, Sweden. Maria.Nordwall@lio.se.|Division of Paediatrics, Department of Molecular and Clinical Medicine, Faculty of Health Science, 581 83, Linköping, Sweden. Maria.Nordwall@lio.se.
Bojestig
M
M
Division of Internal Medicine and Diabetes Research Centre, Department of Medicine and Care, University Hospital, Linköping, Sweden.|Department of Medicine, Eksjö Hospital, Eksjö, Sweden.
Arnqvist
H J
HJ
Division of Internal Medicine and Diabetes Research Centre, Department of Medicine and Care, University Hospital, Linköping, Sweden.
Ludvigsson
J
J
Division of Paediatrics and Diabetes Research Centre, Department of Molecular and Clinical Medicine, University Hospital, Linköping, Sweden.
D000293:Adolescent; D017668:Age of Onset; D002648:Child; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology / Q000503:physiopathology*; D003928:Diabetic Nephropathies / Q000453:epidemiology* / Q000401:mortality / Q000517:prevention & control; D003930:Diabetic Retinopathy / Q000453:epidemiology* / Q000401:mortality / Q000517:prevention & control; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D011627:Puberty; D016019:Survival Analysis; D013548:Sweden / Q000453:epidemiology