To compare the clinical characteristics, case fatality and the impact of ethnicity on YouthOnset and OlderOnset T2DM diagnosed at 15-30 and 40-50 years of age respectively.  Data from 354 YouthOnset individuals collected over 20 years were retrieved from our computer system and then matched (1:3) for duration of diabetes to 1062 OlderOnset individuals.  Clinical parameters for the first and last visits were examined.  Case fatality of each group was evaluated by cross-referencing against the National Death Index.  

The YouthOnset group had a stronger family history of diabetes (p<0.0001).  Despite their younger age, they were equally affected by features of the metabolic syndrome but were less commonly on treatment for hypertension and dyslipidaemia (p<0.0001). There was no difference in the updated HbA1c and prevalence of retinopathy between the two groups.  However, the YouthOnset group had more albuminuria (p=0.01) and neuropathy (p=0.002). The YouthOnset group died at an earlier age, at a disadvantage of 16 years and after the same duration of diabetes, usually from vascular disease (50%) (Logrank test x²=14.6; p=0.0001).  The deceased individuals of YouthOnset group could not be distinguished from the survivors by any clinical criteria at their first visit but at the last visit which occurred at a median of 5.1years before death, the deceased group had more albuminuria, hypertension, peripheral artery disease and stroke (p=0.01). There were no treatment differences between ethnic groups in YouthOnset cohort but the Anglo-Celtic, Aboriginals and Arabs had more IHD (16, 23,18% respectively ) (x²=21; p=0.01) and high mortality (19, 21, 8% respectively) (p=0.04) compare with other ethnic groups. 

We conclude that Youth Onset T2DM suffers at least a 16 years excessive loss in life expectancy. Their cardiovascular risk factors should be treated more intensively from the beginning.