Objective

1. Ambulatory Blood Pressure Profiles in Adolescents with Type 1 DiabetesAndrew J. Ellis1,2, B.A.; David M. Maahs2, M.D. Ph.D.; Franziska K. Bishop2, M.S.; R. Paul Wadwa2, M.D.1-Saint Louis University School of Medicine, Saint Louis, MO2-Barbara Davis Center for Childhood Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO Background Results Conclusions • Lack of nocturnal dip in SBP is present in adolescents with T1D and is associated with older age. • T1D adolescents with non-dipping had HbA1c, BMI, blood pressure, and lipids that trended towards a worse CVD risk factor profile compared to those with normal nocturnal dipping. • Further studies are needed to determine if BMI, HbA1c, in clinic blood pressure measurements and lipid levels are significantly associated with non-dipping in adolescents with T1D. • Determination of modifiable factors associated with abnormal ABP may lead to more aggressive blood pressure treatment and lowering of lifetime risk for CVD for adolescents with T1D. • Cardiovascular disease (CVD) is the leading cause of mortality in patients with type 1 diabetes (T1D). • Adolescents with T1D have an increased risk for the development of CVD and those with abnormal blood pressure are at even higher risk for premature CVD. • Ambulatory blood pressure (ABP) monitoring has been shown to be a useful measure of blood pressure that may be more sensitive than traditional in-clinic blood pressure assessment. • Nocturnal decrease in blood pressure, or “dipping”, is a normal physiologic occurrence. • Abnormal dipping or reduced fall in blood pressure (“non-dipping”) has been associated with diabetic nephropathy in adults with T1D. • There were no differences between males and females with respect to age, diabetes duration, HbA1c, BMI, total cholesterol, HDL-c, LDL-c and urine ACR. • Out of 29 participants, 15 (52%) had an abnormal (<10%) decrease in nocturnal SBP (“non-dippers”). • Participants who had an abnormal SBP dip were older than those with a normal SBP dip (Table 1). • Participants with T1D who had an abnormal SBP dip had a higher BMI than patients with a normal dip (Table 1). • Although differences did not reach statistical significance, HbA1c, total cholesterol, LDL-c, clinic SBP, and clinic DBP trended higher and HDL-c trended lower in non-dippers compared to participants with normal nocturnal SBP dip (p>0.05). • In logistic regression analyses, age, but not sex, BMI, clinic blood pressure, lipids or urine ACR, was associated with increased odds of non-dipping (p=0.03 for age). Table 1: Subject Characteristics by dipping status Objective Acknowledgments • The objective of this study was to assess the relationship between ABP profiles and in-clinic blood pressure measurements and to determine factors associated with non-dipping using ABP monitoring in adolescents with T1D age 12-19 years. • We hypothesized that T1D adolescents with an abnormal decrease in blood pressure (non-dippers) would have a worse CVD risk factor profile compared to T1D adolescents with normal nocturnal dipping. • This research project was supported by the following: • NIDDK Medical Student Research Program, Grant 3T32DK063687-09S1 • JDRF Early Career Award (11-2007-694) for Dr. Wadwa • NIDDK DK 075630 for Dr. Maahs • NIH/NCRR Colorado CTSI Grant Number UL1 RR025780. The contents of this abstract are the authors’ sole responsibility and do not necessarily represent official NIH views. Methods • ABP profiles were obtained using a SpaceLabs 90207 monitor in 29 adolescents with T1D (age 14.8+2.4 years, duration 6.2+4.7, HbA1c 9.2+2.0%) who were part of a larger study investigating CVD risk factors in adolescents with T1D. • Participants wore monitors for a 24-hour period with measurements recorded every 20 minutes during the day and every 60 minutes at night and recorded sleep and activity levels. • ABP profiles were analyzed for non-dipping status, defined as an average SBP decrease <10% during sleep compared to average wakeful SBP. • Demographic, anthropometric, and lab data were also collected, including age, gender, T1D duration, BMI, in-clinic blood pressure, HbA1c, lipid levels, and urine albumin:creatinine ratio (ACR). Figure 1: SpaceLabs 90207 ABP Monitor