In a regional cohort of children with T1DM, we found that Pacific Islanders and those of low SES had higher HbA1c levels at 6 months from diagnosis, with an even greater deterioration in glycaemic control in Pacific Island children after 24 months. In addition, children not living with both biological parents also displayed poorer glycaemic control.
Cross-sectional analyses have previously shown that both ethnicity and to a lesser degree SES influence HbA1c
levels in patients with diabetes 
. Other studies have observed that children and adolescents from ethnic minorities display worse glycaemic control 
. African American children and adolescents with T1DM showed a similar marked difference in HbA1c
values, which were 1.3 to 1.5% higher than European Americans 
. Less dramatic differences have been seen in other ethnicities such as New Zealand Maori (HbA1c
1.0% higher than Europeans) 
and American Hispanic children (HbA1c
0.5% higher) 
. However, even though ethnicity is linked to diabetes control (HbA1c
), the key characteristics of minority groups associated with poor glycaemic control have not been well-described. Nonetheless, ethnicity and SES are often associated, and minority ethnic groups tend to be more socially disadvantaged, experiencing higher poverty rates and worse health status 
. Although SES can be associated with poor glycaemic control in children, this is not always the case 
. In this study, we observed that SES on its own influenced HbA1c
, but when combined with ethnicity in a multivariate regression, ethnicity was the greater influence and there was no independent SES effect.
Family living arrangement was also an important factor determining diabetes management, and children living with both their biological parents were associated with better glycaemic control 24 months after diagnosis. Other studies have shown that living with a single parent is associated with poor glycaemic control in children and adolescents 
. In our study, single-parents were combined with other living arrangements, mainly those living in blended-parent families, for which similar association with poor glycaemic control has been previously observed 
With awareness of the risk factors associated with poor glycaemic control, physicians can assist those patients most at risk of inadequate diabetes management in the long-term. This study has identified a number of primary risk factors: Pacific Island ethnicity, lower SES, higher HbA1c 6mo, increased BMI SDS, and living arrangements without both biological parents. Although predictably higher HbA1c 6mo was associated with higher HbA1c 24mo, the relationship was weak.
Recently, a study found that HbA1c
at 1 year in children with T1DM would not allow practitioners to predict the trajectory of glycaemic control over the subsequent 3 years 
, but other physiological and environmental factors were not included in their analysis. Thus, to better predict glycaemic control at 24 months from diagnosis (i.e. HbA1c 24mo
), we have developed a multivariate regression equation using demographic characteristics at diagnosis and clinical features 6 months afterwards (including HbA1c 6mo
). The equation not only identifies primary risk factors associated with inadequate diabetes management, but also enables clinicians to estimate long-term glycaemic control. The regression equation estimating HbA1c
24 months after diagnosis included three factors: HbA1c 6mo
, ethnicity, and family living arrangements. So, for example, the model predicts with 95% confidence that a Pacific Island child with an HbA1c 6mo
of 7.9% from a single-parent family would have HbA1c
24 months after diagnosis of 10.3±0.6 (mean ± SD). Alternatively, a European child with HbA1c 6mo
of 7.3% living with two biological parents would have HbA1c
24 months after diagnosis of 8.1±0.2.
Shortly after diagnosis, children with T1DM have a temporary but appreciable residual insulin secretion (remission phase), which may disguise attributes associated with poor glycaemic control. We observed that 6 months after diagnosis a third of T1DM children were in the remission phase, but by 24 months virtually no children remained in this phase. These data are consistent with values obtained in other studies 
In the months after diagnosis clinicians may not adjust for the impact of the remission phase. In this period glycemic control can appear satisfactory, but it is in fact too high for the remission phase. Other studies have not examined changes in HbA1c levels from within and then beyond this remission phase. Thus, in the first few months following diagnosis, most children with T1DM appear to have good glycaemic control, creating an illusion that their diabetes is well managed. Once the remission phase is over, HbA1c levels are more likely to reflect actual diabetes management, rather than endogenous insulin secretion.
The end of this remission phase unmasks non-compliant patients, which show a dramatic increase in HbA1c
levels, signalling poor glycaemic control. In our study, although Pacific Island children initially had only a slightly higher HbA1c 6mo
than European children, this difference was considerably amplified after the remission phase. As a result, there was a marked deterioration in glycaemic control 24 months after diagnosis among Pacific Island children, whose mean HbA1c 24mo
was 9.9% compared to 8.1% among Europeans. Importantly, the remission phase can be prolonged with more intensive insulin treatment and could be of considerable benefit to Pacific Island children 
. Interestingly, the remission phase among Pacific Island children was very short, and 83% of subjects transitioned out of this phase within 6 months of diagnosis which occurred more than twice as quickly as for European children. Thus, inadequate diabetes management characteristics were likely to have been present among Pacific Island children shortly after diagnosis.
Obesity among Pacific Islanders is extremely high, and a recent representative study of 1011 Pacific Island adults in Auckland showed that 74% of women and 53% of men were obese 
. Obesity among Pacific Island children is also very common (approximately 24–26%) and rates are considerably higher than in other ethnic groups 
. The rate of obesity in diabetic Pacific Island children in this study was even higher (67%), and we speculate that it may be a major contributor to their poor glycaemic control and shorter remission phase. However, obesity in European children was found to be only weakly associated with HbA1c.
Pacific Islanders suffer from greater morbidity and mortality than other ethnic groups in New Zealand 
, with greater prevalence of diabetes and metabolic syndrome than Europeans 
. A study of over 13,000 patients with T1DM and T2DM attending general practices in the South Island showed that Pacific Islanders/Maori also had poorer glycaemic control than Europeans 
. Although genetics may be a factor 
, cultural and environmental factors other than SES are likely to be at play as observed elsewhere 
, and Pacific Islanders in this study are likely to be representative of minority ethnicities in other countries.
We also found that the prevalence and severity of DKA at diagnosis was considerably greater among girls. Further, girls had worse glycaemic control than boys, a pattern that has been previously observed 
. Differences in metabolism and/or pubertal status between the sexes may account for these differences, and Hoffman et al
. showed that early pubertal girls were less insulin sensitive than boys, but that this difference was compensated by increased insulin secretion 
Deterioration in glycaemic control typically occurs from 6 months to 24 months after diagnosis in children with T1DM. This pattern is particularly marked in Pacific Island children and in those not living with both biological parents. Clinicians need to be aware of factors associated with poor glycaemic control beyond the remission phase, so that more effective measures can be implemented shortly after diagnosis to prevent deterioration in diabetes management.