title: Vulnerable caregivers of Alzheimer disease patients have a deficit in beta 2-adrenergic receptor sensitivity and density.
abstract: OBJECTIVE
  The chronic stress of caregiving may lead to sympathetic nervous system activation and immune suppression. beta(2)-adrenergic receptors are expressed on all immune cells and contribute to the stress-induced loss of immune-cell function. The authors examined the effects of being a spousal caregiver of a patient with Alzheimer disease (AD) on the lymphocyte beta(2)-adrenergic receptor.
  
  
  METHODS
  One hundred and six women and men, spousal caregivers and non-caregivers, participated (mean age: 71.5 years). Caregivers were classified as either vulnerable or non-vulnerable on the basis of the amount of care required by the patient relative to the amount of respite the caregiver received during the previous 6 months. beta(2)-adrenergic receptor sensitivity (cyclic-AMP response to isoproterenol stimulation) and density (radioligand binding) were determined by use of whole lymphocytes.
  
  
  RESULTS
  Vulnerable caregivers had reduced beta(2)-adrenergic receptor sensitivity and density when compared with their non-vulnerable counterparts or with non-caregivers.
  
  
  CONCLUSIONS
  The findings indicate that for more vulnerable caregivers, the stress of caregiving leads to a loss of lymphocyte beta(2)-adrenergic receptors. This finding may be relevant to previous observations of clinically-relevant reduced immunity in highly stressed caregivers of AD patients.
authors.affiliation: Department of Psychiatry, University of California San Diego, 92103-0804, USA. pmills@ucsd.edu
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Mills
authors.forename: Karen A
authors.initials: KA
authors.lastname: Adler
authors.forename: Joel E
authors.initials: JE
authors.lastname: Dimsdale
authors.forename: Christy J
authors.initials: CJ
authors.lastname: Perez
authors.forename: Michael G
authors.initials: MG
authors.lastname: Ziegler
authors.forename: Sonia
authors.initials: S
authors.lastname: Ancoli-Israel
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Patterson
authors.forename: Igor
authors.initials: I
authors.lastname: Grant
mesh_terms: D000368:Aged; D000544:Alzheimer Disease; D001008:Anxiety Disorders / Q000378:metabolism / Q000523:psychology; D001665:Binding Sites; D017028:Caregivers / Q000523:psychology*; D002452:Cell Count; D017281:Cost of Illness; D000242:Cyclic AMP / Q000378:metabolism; D003866:Depressive Disorder / Q000378:metabolism / Q000523:psychology; D005260:Female; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D018343:Receptors, Adrenergic, beta-2 / Q000378:metabolism*; D012680:Sensitivity and Specificity; D013315:Stress, Psychological / Q000378:metabolism* / Q000523:psychology*; D013566:Sympathomimetics / Q000494:pharmacology; D035862:Vulnerable Populations / Q000706:statistics & numerical data*
chemical_list: D018343:Receptors, Adrenergic, beta-2; D013566:Sympathomimetics; D000242:Cyclic AMP; D007545:Isoproterenol