Frequency and Severity of the Dawn Phenomenon in Type 2 Diabetes Relationship to age

OBJECTIVE-To know whether age has an independent effect on the dawn phenomenon in noninsulin-using type 2 diabetes. RESEARCH DESIGN AND METHODS-Eighty-one individuals with type 2 diabetes were matched for HbA(1c) and divided by age into three subgroups of 27 individuals (1: >= 70 years; 2: 60-69 years; and 3: <= 59 years). All underwent ambulatory continuous glucose monitoring for quantifying the dawn phenomenon (i.e., the absolute [partial derivative G, mg/dL] or relative [partial derivative G%] increments from nocturnal nadirs to prebreakfast time points). RESULTS-HbA(1c) levels and 24-h glycemic profiles were similar across the three groups. Glucose increments (mean +/- SEM) were identical in the three groups: partial derivative G (mg/dL), 22.0 +/- 4.7 (1), 21.3 +/- 3.6 (2), and 18.0 +/- 3.6 (3) and partial derivative G(%), 19.9 +/- 4.9 (1), 21.6 +/- 4.4 (2), and 17.6 +/- 4.2 (3). Using the most common definition (partial derivative G >10 mg/dL), the prevalence of the dawn phenomenon was 52, 70, and 59% in groups 1, 2, and 3, respectively. CONCLUSIONS-The dawn phenomenon is present in the elderly.