Title : Classification of 80-year-old individuals into healthy, moderately healthy and frail based on different frailty scores, affects the interpretation of laboratory results
Background Interpretation laboratory analytes is crucial when assessing the patient’s condition. Reference intervals from apparently healthy, disease-free individuals may cause problems when outcomes from elderly patients with chronic diseases and on medications are being interpreted. Elderly individuals is a heterogenous group ranging from individuals managing their daily life independently to individuals with diseases and impairment, in need of nursing care around the clock i.e. frail; a term widely used although there is no consensus on the definition.
Aims To study the effect of classification of elderly into healthy, moderately healthy and frail, based on activities of daily living (ADL) and Mini-Mental State Examination (MMSE) or Frailty Index (FI), on the interpretation of outcomes regarding: albumin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine and gamma-glutamyltransferase (g-GT) levels.
Methods Individuals >=80 years (n=568), were classified either on ADL and MMSE, or number of deficits, (FI).
Results Individuals classified as frail based on FI had lower mean levels for ALT, creatinine and g-GT than individuals classified based on ADL and MMSE (p<0.05).
Discussion When dividing the elderly into healthy, moderately healthy, and frail, as in the present study, the reference intervals provided by the Nordic Reference Interval Project seem to be appropriate for the healthy and moderately healthy, but not for the group of frail elderly individuals, independent of classification model.
The model to define health status to some extent affected laboratory analyte levels in ≥80-year-olds, classified as healthy, moderately healthy and frail based on ADL and MMSE versus FI.