medwireNews: Changes in adiponectin levels in adolescents with type 2 diabetes predict treatment response and may even underlie racial differences in treatment response, show data from the TODAY study.
Contrary to the researchers’ expectations, baseline levels of adiponectin did not predict treatment response, despite the known antidiabetic effects of adiponectin and its reduced levels in type 2 diabetes patients.
Laure El ghormli (George Washington University, Rockville, Maryland, USA) and team looked at high-molecular-weight adiponectin (HMWA), along with insulin sensitivity and C-peptide index, because these are known to vary among people of different ethnicities. They hoped to explain why oral antidiabetic treatment was less successful in the 227 Black participants of TODAY than the 278 Hispanic and 142 White patients (all aged 10–17 years).
During 36 months of treatment (with metformin alone or with rosiglitazone or lifestyle intervention) changes in insulin sensitivity and C-peptide index were similar regardless of ethnicity. But HMWA levels were lower at baseline in Black patients than in Hispanic and White patients (2411 vs 3083 and 3124 ng/mL, respectively) and remained lower during treatment.
HMWA levels rose in all ethnic groups over the first 6 months, and each standard deviation increase was associated with a significant 39% reduction in the likelihood of treatment failure during follow-up (glycated hemoglobin ≥8% for 6 months, or need for insulin). Baseline glycated hemoglobin levels and oral disposition index also predicted treatment success, but the predictive power of HMWA remained after accounting for these factors and adjusting for variables including age, gender, treatment group, and baseline body mass index.
The relationship between HMWA increases and treatment success was significant for all ethnicities; however, the 6-month increase in HMWA was less in Black patients (17.3%) than in Hispanic and White patients (29.9 and 33.7%, respectively).
This therefore “provides a possible explanation for the higher therapeutic failure rates in [non-Hispanic Blacks] than in the other two racial/ethnic groups,” write the researchers in Diabetes Care.
They caution that it is not clear if this is caused by ethnic biologic/genetic differences or if it could be explained by treatment adherence, although they note that adherence according to pill count did not differ by ethnicity.
Baseline glycated hemoglobin level was the most powerful predictor of treatment failure, with an accuracy of 65%, but adding HMWA improving the accuracy by a significant 4 percentage points, to 69%.
“Therefore, adiponectin levels may carry prognostic value for diabetes course beyond the currently recognized set of risk factors,” says the team.
medwireNews is an independent medical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2016