1. Ambulatory Blood Pressure Profiles in Adolescents with Type 1 Diabetes Andrew J. Ellis 1,2, B.A.; David M. Maahs 2, M.D. Ph.D.; Franziska K. Bishop 2, M.S.; R. Paul Wadwa 2, M.D. 1 -Saint Louis University School of Medicine, Saint Louis, MO 2 -Barbara Davis Center for Childhood Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO Objective 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). 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. 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. Background Methods 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. 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. 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). Results Acknowledgments Table 1: Subject Characteristics by dipping status SBP Dip >10%SBP Dip <10%P-value N1415N/A Age (years)13.7+1.816.0+2.30.007 T1D duration (years)6.0+4.26.7+5.40.67 Sex, % male43%67%0.20 BMI (kg/m 2 )20.0+2.423.4+4.40.03 Clinic SBP (mmHg)111.1+5.3117.1+10.10.07 Clinic DBP (mmHg) 68.7+4.9 72.1+10.50.39 HbA1c (%)8.7+1.59.9+2.30.12 Total Cholesterol (mg/dL)157.9+24.0166.7+46.70.61 HDL-c (mg/dL)53.6+9.050.7+12.00.47 LDL-c (mg/dL)87.9+15.497.3+30.50.41 Urine Albumin:Creatinine Ratio61.8+1338.23+5.590.17 Figure 1: SpaceLabs 90207 ABP Monitor