title: The effect of overt and subclinical hypothyroidism on the development of non-dipper blood pressure.
abstract: BACKGROUND
  'Non-dippers' are individuals without the anticipated nocturnal decrease in blood pressure. An increased incidence of target organ damage and a worse outcome in terms of cardiovascular events have been reported in this group of people. The pathogenesis of non-dipper hypertension is not clear at present. We aimed to investigate the effects of overt and subclinical hypothyroidism on the development of a non-dipper blood pressure pattern via 24-hour ambulatory blood pressure monitoring.
  
  
  METHODS
  109 normotensive patients with overt and subclinical hypothyroidism were evaluated, and 95 of these patients without reverse dipping and masked hypertension were included in the study. The control group consisted of 75 gender- and age-matched, normotensive, euthyroid healthy individuals.
  
  
  RESULTS
  Median serum TSH levels were 7.61 and 1.59 mUmL in patient and control groups, respectively. The number of non-dippers according to systolic, diastolic and mean blood pressure was significantly higher in the patients with hypothyroidism compared to the control group. In linear regression analysis, TSH had a negative effect on the night/day ratio of the systolic, diastolic and mean blood pressures.
  
  
  CONCLUSIONS
  Despite the fact that the effect of hypothyroidism on non-dipper blood pressure pattern is not known, the present study has revealed that elevated TSH levels are likely to increase the risk of non-dipping in normotensive patients with either overt or subclinical hypothyroidism.
authors.affiliation: Department of Nephrology Beşevler, Gazi University Medical School, Ankara, Turkey. salihinal@yahoo.com
authors.forename: Salih
authors.initials: S
authors.lastname: Inal
authors.forename: Mehmet A
authors.initials: MA
authors.lastname: Karakoç
authors.forename: Erdal
authors.initials: E
authors.lastname: Kan
authors.forename: Fatma A
authors.initials: FA
authors.lastname: Ebinç
authors.forename: Füsun B
authors.initials: FB
authors.lastname: Törüner
authors.forename: Metin
authors.initials: M
authors.lastname: Aslan
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination; D018660:Blood Pressure Monitoring, Ambulatory; D016022:Case-Control Studies; D002940:Circadian Rhythm / Q000502:physiology*; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000150:complications* / Q000503:physiopathology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D013972:Thyrotropin / Q000378:metabolism*
chemical_list: D013972:Thyrotropin