title: Effect of normal aging versus hypertension, abnormal body mass index, and diabetes mellitus on white matter hyperintensity volume.
abstract: OBJECTIVE
  The natural history of white matter hyperintensity (WMH) progression resulting from normal aging versus comorbid vascular insults remains unclear. Therefore we investigated age-related differences in WMH volumes among a group with comorbid hypertension, abnormal body mass index, and diabetes mellitus to a normal aging group drawn from the same population lacking any of these comorbidities.
  
  
  METHODS
  WMH volumes were acquired using 3T MRI for 2011 Dallas Heart Study participants. The slope of the WMH versus age regression was compared between normal and comorbidity groups<50 and ≥50 years of age where a change in slope was demonstrated.
  
  
  RESULTS
  Aging was linearly associated with greater log WMH volume for both normal (P=0.02) and comorbidity (P<0.0001) groups. Beyond 50 years of age, more rapid increases in WMH volumes for age were seen in the group with comorbidities (P<0.0001) but not in the normal group (P=0.173). The between-group difference in slope of expected WMH for age was significantly greater in the comorbidity groups≥50 years of age (P=0.0008) but not <50 years of age (P=0.752).
  
  
  CONCLUSIONS
  After 50 years of age, but not before, comorbid hypertension, obesity, and diabetes mellitus were associated with significantly larger WMH volumes for age compared with a normal aging group lacking these conditions. These results support the assertion that age-related differences in WMH volumes are significantly increased in the presence of comorbidities, but the effect is only detectable after 50 years of age.
authors.affiliation: From the Departments of Radiology (K.S.K., R.M.P., R.W.M., K.M.H.), Internal Medicine (R.M.P., C.R.A., S.R.D.), and Psychiatry (H.C.R.), University of Texas Southwestern Medical Center, Dallas, TX.
authors.forename: Kevin S
authors.initials: KS
authors.lastname: King
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Peshock
authors.forename: Heidi C
authors.initials: HC
authors.lastname: Rossetti
authors.forename: Roderick W
authors.initials: RW
authors.lastname: McColl
authors.forename: Colby R
authors.initials: CR
authors.lastname: Ayers
authors.forename: Keith M
authors.initials: KM
authors.lastname: Hulsey
authors.forename: Sandeep R
authors.initials: SR
authors.lastname: Das
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology / Q000502:physiology*; D015992:Body Mass Index; D001921:Brain / Q000473:pathology*; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000473:pathology*; D005006:Ethnicity; D005260:Female; D006801:Humans; D006973:Hypertension / Q000473:pathology*; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000473:pathology; D012044:Regression Analysis; D012307:Risk Factors; D012737:Sex Factors; D012959:Socioeconomic Factors
keywords: aging; white matter hyperintensity