Effect of parental type 2 diabetes on offspring with type 1 diabetes.
OBJECTIVE
The purpose of this study was to study the association between a parental history of type 2 diabetes and the metabolic profile as well as the presence of the metabolic syndrome and diabetes complications in patients with type 1 diabetes.


METHODS
This was a cross-sectional study design in 1,860 patients with type 1 diabetes from the Finnish Diabetic Nephropathy (FinnDiane) Study (620 patients with and 1,240 age-matched patients without a parental history of type 2 diabetes). Information on parental history was received from the type 1 diabetic offspring by a standardized questionnaire.


RESULTS
Patients with type 1 diabetes and a positive parental history of type 2 diabetes had a higher prevalence of the metabolic syndrome (44 vs. 38%; P = 0.013) and a metabolic profile related to insulin resistance (higher BMI, larger waist circumference, and higher triglycerides, A1C, and insulin dose per kilogram) and also had a later onset of type 1 diabetes (17.2 +/- 9.2 vs. 16.1 +/- 8.9 years; P = 0.008), which was also confirmed in the publicly available Diabetes Control and Complications Trial data set. In contrast, no association was observed with blood pressure, diabetes complications, or HLA genotype distribution. Parental history of type 2 diabetes was independently associated with age at onset of type 1 diabetes (odds ratio 1.02 [95% CI 1.01-1.03]), BMI (1.07 [1.02-1.12]), triglycerides (1.18 [1.03-1.35]), and insulin dose per kilogram (1.63 [1.04-2.54]).


CONCLUSIONS
Parental history of type 2 diabetes is associated with a later onset of type 1 diabetes, the metabolic syndrome, and a metabolic profile related to insulin resistance.
Folkhälsan Institute of Genetics, Folkhälsan Research Center, Biomedicum Helsinki, Helsinki, Finland.
Lena M
LM
Thorn
Carol
C
Forsblom
Johan
J
Wadén
Jenny
J
Söderlund
Milla
M
Rosengård-Bärlund
Markku
M
Saraheimo
Outi
O
Heikkilä
Kustaa
K
Hietala
Kim
K
Pettersson-Fernholm
Jorma
J
Ilonen
Per-Henrik
PH
Groop
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D015992:Body Mass Index; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics; D008297:Male; D024821:Metabolic Syndrome / Q000235:genetics*; D008875:Middle Aged; D009679:Nuclear Family; D010290:Parents; D011795:Surveys and Questionnaires; D055105:Waist Circumference