Discordant trends in microvascular complications in adolescents with type 1 diabetes from 1990 to 2002.
OBJECTIVE
Since the Diabetes Control and Complications Trial, diabetes management goals have changed. The aims of the present study were to assess complication rates, including nerve abnormalities, in adolescents from 1990 to 2002 and to investigate associated risk factors.


METHODS
Cross-sectional analysis of complications was assessed in three study periods (1990-1994 [T1], 1995-1998 [T2], and 1999-2002 [T3]) in adolescents matched for age and diabetes duration (n = 878, median age 14.6 years, median duration 7.5 years). Retinopathy was assessed by seven-field stereoscopic fundal photography, albumin excretion rate (AER) from three consecutive timed overnight urine collections, peripheral nerve function by thermal and vibration thresholds, and autonomic nerve function by cardiovascular reflexes.


RESULTS
Retinopathy declined significantly (T1, 49%; T2, 31%; and T3, 24%; P < 0.0001), early elevation of AER (> or = 7.5 microg/min) declined (38, 30, and 25%, respectively, P = 0.022), and microalbuminuria (AER > or = 20 microg/min) declined (7, 3, and 3%, respectively; P = 0.017, T1 vs. T2 and T3). Autonomic nerve abnormalities were unchanged (18, 21, and 18%, respectively; P = 0.60), but peripheral nerve abnormalities increased (12, 19, and 24%, respectively; P = 0.0017). More patients were treated with three or more injections per day (12, 46, and 67%, respectively; P < 0.0001) and insulin dose increased (1.08, 1.17, and 1.22 units x kg(-1) x day(-1), respectively; P < 0.0001), but median HbA(1c) (A1C) was unchanged (8.5, 8.5, and 8.4%, respectively). BMI and height SD score increased: BMI 0.46, 0.67, and 0.79, respectively (P < 0.0001), and height -0.09, 0.05, and 0.27, respectively (P < 0.0001).


CONCLUSIONS
Retinopathy and microalbuminuria declined over time in this cohort, but the increased rate of peripheral nerve abnormalities is of concern. Despite intensified management (higher insulin dose and more injections), A1C has not changed and remains well above the recommended targets for adolescents.
Mohsin
Fauzia
F
Institute of Endocrinology and Diabetes, Locked Bag 4001, Westmead, NSW 2145, Australia.
Craig
Maria E
ME
Cusumano
Janine
J
Chan
Albert K F
AK
Hing
Stephen
S
Lee
Jennifer W
JW
Silink
Martin
M
Howard
Neville J
NJ
Donaghue
Kim C
KC
D000293:Adolescent; D000328:Adult; D000419:Albuminuria / Q000453:epidemiology; D001794:Blood Pressure; D002648:Child; D002784:Cholesterol / Q000097:blood; D003430:Cross-Sectional Studies; D003710:Demography; D003922:Diabetes Mellitus, Type 1 / Q000150:complications*; D003925:Diabetic Angiopathies / Q000097:blood / Q000453:epidemiology* / Q000503:physiopathology; D003929:Diabetic Neuropathies / Q000097:blood / Q000453:epidemiology / Q000503:physiopathology; D003930:Diabetic Retinopathy / Q000097:blood / Q000453:epidemiology* / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D015994:Incidence; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D012307:Risk Factors; D012959:Socioeconomic Factors
D007328:Insulin; D002784:Cholesterol