Albuminuria in recent-onset type 2 diabetes: The Strong Heart Study

OBJECTIVE - It is not known how frequently abnormal albumin excretion occurs in the initial years after the onset of type 2 diabetes and to what extent its occurrence is related to the severity of diabetes. We have used a prospective cohort study to examine this. RESEARCH DESIGN AND METHODS - A total of 782 participants from the Strong Heart Study who had normal glucose tolerance and normal albumin excretion (albumin-to-creatinine ratio <30 mg albumin/g creatinine) at baseline were assessed for diabetes and abnormal albumin excretion at a follow-up visit (interval 3.91 ± 0.95 years, mean ± SD). Logistic regression models were used to examine the associations. RESULTS - Abnormal albumin excretion was detected in 52 (6.6%) and diabetes was determined to be present in 105 (13.4%) of the participants at the follow-up visit. In univariate analyses, abnormal albumin excretion was statistically significantly related to the baseline albumin-to-creatinine ratio, diastolic blood pressure, fasting insulin, and extent of American Indian heritage. Abnormal albumin excretion was much more prevalent in those with recent onset diabetes at the follow-up visit (18 vs. 5%, P < 0.001). In a logistic regression analysis, abnormal albumin excretion and diabetes remained strongly related (odds ratio 3.45, P < 0.001), and associations of abnormal albumin excretion with baseline albumin-to-creatinine ratio, blood pressure, and American Indian heritage also remained significant in a separate logistic regression analysis, including only those who developed diabetes. There was a strong association between abnormal albumin excretion and fasting glucose levels (<0.01) at the follow-up visit. CONCLUSIONS - These data suggest that an appreciable percentage of individuals develop abnormal albumin excretion within the first few years after the onset of type 2 diabetes. Also, the severity of diabetes at onset appears to be a key risk factor for the early development of abnormal albumin excretion.