Prevalence, incidence and types of mild anemia in the elderly: the "Health and Anemia" population-based study.
BACKGROUND
Hemoglobin concentrations slightly below the lower limit of normal are a common laboratory finding in the elderly, but scant evidence is available on the actual occurrence of mild anemia despite its potential effect on health. The objectives of this study were to estimate the prevalence and incidence of mild grade anemia and to assess the frequency of anemia types in the elderly.


METHODS
This was a prospective, population-based study in all residents 65 years or older in Biella, Italy.


RESULTS
Blood test results were available for analysis from 8,744 elderly. Hemoglobin concentration decreased and mild anemia increased steadily with increasing age. Mild anemia (defined as a hemoglobin concentration of 10.0-11.9 g/dL in women and 10.0-12.9 g/dL in men) affected 11.8% of the elderly included in the analysis, while the estimated prevalence in the entire population was 11.1%. Before hemoglobin determination, most mildly anemic individuals perceived themselves as non-anemic. Chronic disease anemia, thalassemia trait, and renal insufficiency were the most frequent types of mild anemia. The underlying cause of mild anemia remained unexplained in 26.4% of the cases, almost one third of which might be accounted for by myelodysplastic syndromes. In a random sample of non-anemic elderly at baseline (n=529), after about 2 years, the annual incidence rate of mild anemia was 22.5 per 1000 person-years and increased with increasing age.


CONCLUSIONS
The prevalence and incidence of mild anemia increase with age and mild anemia affects more than one out of ten elderly individuals. Unexplained anemia is common and may be due to myelodysplastic syndromes in some cases.
Tettamanti
Mauro
M
Laboratory of Geriatric Neuropsychiatry, Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan, Italy.
Lucca
Ugo
U
Gandini
Francesca
F
Recchia
Angela
A
Mosconi
Paola
P
Apolone
Giovanni
G
Nobili
Alessandro
A
Tallone
Maria Vittoria
MV
Detoma
Paolo
P
Giacomin
Adriano
A
Clerico
Mario
M
Tempia
Patrizia
P
Savoia
Luigi
L
Fasolo
Gilberto
G
Ponchio
Luisa
L
Della Porta
Matteo G
MG
Riva
Emma
E
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000097:blood / Q000453:epidemiology* / Q000235:genetics; D002908:Chronic Disease; D005260:Female; D006454:Hemoglobins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D040641:Quantitative Trait Loci; D051437:Renal Insufficiency / Q000097:blood / Q000453:epidemiology / Q000235:genetics; D013789:Thalassemia / Q000097:blood / Q000453:epidemiology / Q000209:etiology / Q000235:genetics
D006454:Hemoglobins