title: Impaired systolic blood dipping and nocturnal hypertension: an independent predictor of carotid intima-media thickness in type 1 diabetic patients.
abstract: OBJECTIVE
  Type 1 diabetes in children predicts a broad range of later health problems including an increased risk of cardiovascular morbidity and mortality. This study aimed to evaluate whether nocturnal hypertension and impaired nocturnal dipping affect atherosclerosis in children and adolescents with type 1 diabetes and to investigate the relationship between atherogenic risk factors and carotid intima-media thickness (CIMT).
  
  
  METHODS
  One hundred fifty-nine type 1 diabetic patients and 100 healthy controls were included in the study. We investigated metabolic and anthropometric parameters such as body mass index (BMI), waist circumference, fasting glucose and insulin, serum lipids, 24h ambulatory blood pressure monitoring (ABPM), and CIMT and compared these with those in control subjects (CS).
  
  
  RESULTS
  No difference was found between type 1 diabetic patients and CS in age, weight, waist/hip ratio, triglyceride, HDL-cholesterol level. However in children with type 1 diabetes, total cholesterol (p=0.016),and LDL-cholesterol (p=0.002) levels and CIMT (P<0.001) were greater than those of controls. It was determined that 10% of type 1 diabetic patients had dyslipidemia. In 23.2% of type 1 diabetic patients, ABPM showed arterial hypertension. CIMT was significantly higher in the hypertensive group than in the non-hypertensive group (P=0.003). Twenty-three (14.4%) diabetic patients had nocturnal hypertension. CIMT was significantly greater in the nocturnal hypertensive group (p=0.023). Mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) dipping was significantly different in diabetic patients (P<0.001). CIMT was correlated positively with Hba1c (r=0.220, p=0.037), and negatively with SBP dipping (r=-0.362, p=0.020) in the diabetic patients. In stepwise regression analysis, Hba1c and SBP dipping emerged as a significant predictor of CIMT (β=0.300, p=0.044, β=0.398 p=0.009) contributing to 15.58% of its variability.
  
  
  CONCLUSIONS
  These results provide additional evidence for the presence of subclinical cardiovascular disease (CVD) and its relation to hypertension in type 1 diabetic patients. They also indicate a significant relation between nocturnal hypertension, SBP dipping and increased arterial stiffness. It is also important to note that our findings reveal significant relationships between HBA1c cardiovascular changes and underline the importance of glucose control to predict CVD.
authors.affiliation: Department of Pediatric Endocrinology and Diabetes, School of Medicine, Necmettin Erbakan University, Konya, Turkey.
authors.forename: Mehmet Emre
authors.initials: ME
authors.lastname: Atabek
authors.affiliation: Department of Pediatric Endocrinology and Diabetes, School of Medicine, Necmettin Erbakan University, Konya, Turkey. Electronic address: n_akyurek@yahoo.com.tr.
authors.forename: Nesibe
authors.initials: N
authors.lastname: Akyürek
authors.affiliation: Department of Pediatric Endocrinology and Diabetes, School of Medicine, Necmettin Erbakan University, Konya, Turkey.
authors.forename: Beray Selver
authors.initials: BS
authors.lastname: Eklioglu
authors.affiliation: Department of Pediatric Cardiology School of Medicine, Necmettin Erbakan University, Konya, Turkey.
authors.forename: Hayrullah
authors.initials: H
authors.lastname: Alp
mesh_terms: D000293:Adolescent; D050197:Atherosclerosis / Q000000981:diagnostic imaging / Q000209:etiology; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D059168:Carotid Intima-Media Thickness; D002648:Child; D002940:Circadian Rhythm; D003922:Diabetes Mellitus, Type 1 / Q000150:complications* / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008137:Longitudinal Studies; D008297:Male; D011379:Prognosis; D012307:Risk Factors; D013599:Systole
keywords: Ambulatory blood pressure; Subclinical cardiovascular disease; Type 1 diabetes