Vulnerable caregivers of Alzheimer disease patients have a deficit in beta 2-adrenergic receptor sensitivity and density

Am J Geriatr Psychiatry. May-Jun 2004;12(3):281-6.

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.

Conclusion: 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.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Alzheimer Disease*
  • Anxiety Disorders / metabolism
  • Anxiety Disorders / psychology
  • Binding Sites
  • Caregivers / psychology*
  • Cell Count
  • Cost of Illness*
  • Cyclic AMP / metabolism
  • Depressive Disorder / metabolism
  • Depressive Disorder / psychology
  • Female
  • Humans
  • Isoproterenol / pharmacology
  • Lymphocytes / metabolism
  • Male
  • Receptors, Adrenergic, beta-2 / metabolism*
  • Sensitivity and Specificity
  • Stress, Psychological / metabolism*
  • Stress, Psychological / psychology*
  • Sympathomimetics / pharmacology
  • Vulnerable Populations / statistics & numerical data*

Substances

  • Receptors, Adrenergic, beta-2
  • Sympathomimetics
  • Cyclic AMP
  • Isoproterenol