Blood haemoglobin declines in the elderly: implications for reference intervals from age 70 to 88.
The objective was to determine whether Hb declines in healthy elderly men and women and if this influences health-related reference intervals. A representative population sample, comprising 30% of all 70-yr-old subjects in a Swedish city with 420,000 inhabitants (n = 1148, participation rate 85%), was followed at 1-5-yr intervals for 18 yr within a longitudinal population study. Age-related changes in Hb were calculated after exclusion of non-healthy probands and by multivariate analyses in the total study group. Mean Hb declined between age 70 and 88 from 149 to 138 g/L in men (annual decline 0.69 g/L, p = 0.000), and from 139 to 135 g/L in women (annual decline 0.06 g/L, n.s.). Healthy men declined from 152 to 141 g/L (annual decline 0.53 g/L, p = 0.038), for women from 140 to 138 g/L (annual decline 0.05 g/L, n.s.). Age and body mass index correlated, in multivariate analysis, independently to Hb in both men and women, as did variables indicating a non-healthy state. Epidemiological decision limits for anaemia declined for men from 128 to 116 g/L, for women from 118 to 114 g/L. Anaemia, thus defined, occurred in 3.2 to 9.7% of the subjects, whereas 28.3% of the 88-yr-old men had anaemia according to the WHO definition. In conclusion, there is a significant age-related decline in Hb from age 70 to 88 among healthy men, and a less pronounced decline among women. This justifies the use of lower epidemiological decision limits for anaemia of about 115 g/L for both men and women from age 80-82.
Nilsson-Ehle
H
H
Department of Medicine, Institute of Internal Medicine, Göteborg University, Sweden. herman.nilsson-ehle@medicine.gu.se
Jagenburg
R
R
Landahl
S
S
Svanborg
A
A
D000367:Age Factors; D000368:Aged / Q000502:physiology*; D000369:Aged, 80 and over; D000740:Anemia / Q000097:blood / Q000453:epidemiology; D001774:Blood Chemical Analysis; D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D006403:Hematologic Tests; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D012016:Reference Values; D012737:Sex Factors; D013548:Sweden / Q000453:epidemiology; D014505:Urban Population
D006454:Hemoglobins