Background: The use of laboratory intervals based on younger and
healthier populations is of questionable validity in older populations. The aim of
this study was to examine haematological and biochemical profiles in a sample of
community-dwelling older people and to study the impact of age, disease, disability
and medications.
Methods: Basic haematological and biochemical values were obtained for
338 survivors of a random sample of community-living people aged 75 years or over at
time of recruitment. These values were compared to the laboratory reference intervals
and the effects of age, disease, medication and disability examined.
Results: The distribution of the 35 parameters measured differed from
those described by the laboratory reference intervals in all but four of the
variables. The values showed few significant age associations but did show
associations with disease, disability and drug use.
Conclusions: Abnormalities identified in haematological and biochemical
testing are not due to age but to age-related illnesses. This is contrary to previous
studies reporting a change in haematological and biochemical parameters purely on the
basis of age. In the presence of abnormalities, identification and clarification of
disease states should be made.
