title: Lithium dosage in the elderly. A study with matched age groups.
abstract: Lithium dosage was examined in 3 age groups (less than or equal to 45 years, 46-64 years, greater than or equal to 65 years) of 78 inpatients, matched on relevant variables. Although mean steady-state lithium plasma levels showed no essential differences, mean daily lithium doses were significantly lower in the elderly. The ratio of weight-related lithium dose to plasma level showed a 36% decline with age (0.58, 0.46 and 0.37 1/kg, P less than 0.0001, analysis of variance). Comparing different decades this ratio, indicating the dose required for a certain plasma level, displayed a clear-cut decrease at 50 years. This may be caused by age-related changes in apparent volume of distribution and/or in elimination half-life of lithium, the latter being the consequence of age-related decrease of glomerular filtration rate.
authors.forename: W
authors.initials: W
authors.lastname: Greil
authors.forename: M C
authors.initials: MC
authors.lastname: Stoltzenburg
authors.forename: M L
authors.initials: ML
authors.lastname: Mairhofer
authors.forename: M
authors.initials: M
authors.lastname: Haag
mesh_terms: D000367:Age Factors; D000368:Aged; D001714:Bipolar Disorder / Q000097:blood / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008094:Lithium / Q000097:blood / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011618:Psychotic Disorders / Q000097:blood / Q000188:drug therapy*
chemical_list: D008094:Lithium