title: The prevalence and natural history of pituitary hemorrhage in prolactinoma.
abstract: BACKGROUND
  Incidental pituitary hemorrhage, without full pituitary apoplexy, is a recognized radiological finding, but little information exists on its clinical behavior, with most reports describing surgically treated macroprolactinoma or nonfunctioning adenoma.
  
  
  OBJECTIVE
  Our aim was to characterize the prevalence, natural history, and risk factors associated with pituitary hemorrhage in a large clinic prolactinoma population.
  
  
  METHODS
  The design consisted of a retrospective analysis of a clinic population.
  
  
  METHODS
  The setting was a tertiary endocrine center in a large teaching hospital.
  
  
  METHODS
  We studied three hundred sixty-eight patients with prolactinoma. The presence of hemorrhage was documented on magnetic resonance imaging.
  
  
  METHODS
  The main outcome measures were the prevalence, risk factors, and natural history of pituitary hemorrhage.
  
  
  RESULTS
  Pituitary hemorrhage was found in 25 patients, giving an overall prevalence of 6.8%, and was significantly higher in macroprolactinoma (20.3%) compared to microprolactinoma (3.1%, P < .0001). Three patients had classical pituitary apoplexy. The majority of patients in the hemorrhage group had macroprolactinomas (16/25 [64%]) and were women (22/25 [88%]). The proportion of women with macroprolactinoma was higher in the hemorrhage group (14/16 macroprolactinomas [87.5%]) than in the nonhemorrhage group (36/63 macroprolactinomas [57.1%], P = .02). The majority of pituitary hemorrhages (92%) were treated conservatively with dopamine agonist therapy for hyperprolactinemia. Eighty-seven percent of patients had complete resolution of their hemorrhage within 26.6 ± 23.3 (mean ± SD) months. The presence of macroprolactinoma (odds ratio 9.00 [95%CI 3.79-23.88], P < .001) and being female (odds ratio 8.03 [95%confidence interval 1.22-52.95], P = .03) were independently associated with hemorrhage.
  
  
  CONCLUSIONS
  These data show that incidental hemorrhage in prolactinoma is not uncommon. It is more likely to occur in macroprolactinoma, where 1 in 5 develop hemorrhage, and is particularly common in women with macroprolactinoma. The majority are asymptomatic and resolve spontaneously.
authors.affiliation: Department of Endocrinology, Guy's and St Thomas' National Health Service (NHS) Foundation Trust, London SE1 9RT, United Kingdom.
authors.forename: K N
authors.initials: KN
authors.lastname: Sarwar
authors.forename: M S B
authors.initials: MS
authors.lastname: Huda
authors.forename: V
authors.initials: V
authors.lastname: Van de Velde
authors.forename: L
authors.initials: L
authors.lastname: Hopkins
authors.forename: S
authors.initials: S
authors.lastname: Luck
authors.forename: R
authors.initials: R
authors.lastname: Preston
authors.forename: B M
authors.initials: BM
authors.lastname: McGowan
authors.forename: P V
authors.initials: PV
authors.lastname: Carroll
authors.forename: J K
authors.initials: JK
authors.lastname: Powrie
mesh_terms: D000328:Adult; D005260:Female; D006470:Hemorrhage / Q000453:epidemiology*; D006801:Humans; D007018:Hypopituitarism / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010900:Pituitary Diseases / Q000453:epidemiology*; D015995:Prevalence; D015175:Prolactinoma / Q000150:complications*; D012189:Retrospective Studies; D012307:Risk Factors