Complications in young adults with early-onset type 2 diabetes: losing the relative protection of youth.
OBJECTIVE
To determine whether adults diagnosed with type 2 diabetes from age 18 to 44 years more aggressively develop clinical complications after diagnosis than adults diagnosed at >or=45 years of age.


METHODS
We compared outcomes among 7844 adults in a health maintenance organization who were newly diagnosed with type 2 diabetes between 1996 and 1998. We abstracted clinical data from electronic medical, laboratory, and pharmacy records. To adjust for length of follow-up and sex, we used proportional hazards models to compare incident complication rates through 2001 between onset groups (mean follow-up 3.9 years). To adjust for the increasing prevalence of macrovascular disease with advancing age, onset groups were matched by age and sex to control subjects without diabetes for macrovascular outcomes.


RESULTS
Adults with early-onset type 2 diabetes were 80% more likely to begin insulin therapy than those with usual-onset type 2 diabetes (hazards ratio [HR] 1.8, 95% CI 1.5-2.0), despite a similar average time to requiring insulin ( approximately 2.2 years). Although the combined risk of microvascular complications did not differ overall, microalbuminuria was more likely in early-onset type 2 diabetes than usual-onset type 2 diabetes (HR 1.2, 95% CI 1.1-1.4). The hazard of any macrovascular complication in early-onset type 2 diabetic patients compared with control subjects was twice as high in usual-onset type 2 diabetic patients compared with control subjects (HR 7.9 vs. 3.8, respectively). Myocardial infarction (MI) was the most common macrovascular complication, and the hazard of developing an MI in early-onset type 2 diabetic patients was 14-fold higher than in control subjects (HR 14.0, 95% CI 6.2-31.4). In contrast, adults with usual-onset type 2 diabetes had less than four times the risk of developing an MI compared with control subjects (HR 3.7, P < 0.001).


CONCLUSIONS
Early-onset type 2 diabetes appears to be a more aggressive disease from a cardiovascular standpoint. Although the absolute rate of cardiovascular disease (CVD) is higher in older adults, young adults with early-onset type 2 diabetes have a much higher risk of CVD relative to age-matched control subjects.
Hillier
Teresa A
TA
Center for Health Research, Kaiser Permanente Northwest/Hawaii, Portland, Oregon 97227, USA. teresa.hillier@kp.org
Pedula
Kathryn L
KL
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000419:Albuminuria / Q000453:epidemiology; D015897:Comorbidity; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors