Anaemia In Nonagenarians: Incidence, Severity and Aetiology

The population of Australians aged 90–99 years has increased by 204% (42,234 to 128,654) [0.25% to 0.59%] between 1990 and 2010 compared to a 30% increase in the general population (17.06 million to 21.99 million) highlighting the trend to aging of the population. At this age bracket the M:F ratio is ~1:3. One third of the Australian population lives in the state of New South Wales (NSW) (www.abs.gov.au). The Australian heathcare system of federally funded pathology has resulted in marked consolidation of pathology providers servicing all non-hospital healthcare settings. Symbion Pathology account for ~35% of all pathology services in NSW and hence closely reflects the community incidence for laboratory diagnosed disorders. Community-based pathology laboratories now see large numbers of patients in this 90–99 year old age range.

We assessed all individual patients aged between 90 and 99 years with anaemia over the 5 year period 2005–2009. Patients were included in the analysis if they had at least one full blood count (FBC/CBC) showing a hemoglobin below the laboratory reference range (RR) of 130g/L for males and 115g/L for females. All duplicate individuals and full blood counts (FBC) were excluded.

There were 4,369 (33.8%) of 12,921 individuals with anaemia. Classification by red cell size showed the majority were normochromic (80.6%), while 5.8% were microcytic and 13.6% were macrocytic.

In microcytic anaemias, 136 (53%) had a ferritin level performed and 63 (46% of this 136 patients) were iron deficient. In macrocytic anaemias, only 149 (25%) had B12 assays and 13 were deficient. In normocytic anaemias, 2910 (82.7%) had urea performed with 1413 patients had urea >10 mmol/L (48%) and 976 patients had urea >12 mmol/L (33%) (RR 3.5–9.0 mmol/L). Pancytopenia was present in 44 (1%) patients. In most patients, anaemia was mild but 25% of females and 50% of males had Hb >15g/L below the lower limit of the RR.

Anaemia is very common in individuals aged 90–99 years occurring in one-third of the population at this age. Half the males and a quarter of females have a Hb >15g/L below the RR making this a significant comorbidity in the very elderly. As might be expected the aetiology is heterogeneous but appears to be frequently under investigated. In particular, simple haematinic assays appear to be under-utilised to better define the aetiology despite being inexpensive and readily available. The study highlights the substantial social, economic and healthcare implications in this era of significant ageing of the population.

No relevant conflicts of interest to declare.