Prevalence of potential underlying aetiology of macrocytic anaemia in Dutch general practice.
BACKGROUND
Macrocytic anaemia (MCV ≥ 100 fL) is a relatively common finding in general practice. However, literature on the prevalence of the different causes in this population is limited. The prevalence of macrocytic anaemia and its underlying aetiology were analysed in a general practice population. The potential effect of the different aetiology on survival was also evaluated.


METHODS
Between the 1st of February 2007 and the 1st of February 2015, patients aged 50 years or older and presenting to their general practitioner with a newly diagnosed anaemia, were included in the study. Anaemia was defined as haemoglobin level below 13.7 g/dL in men and below 12.1 g/dL in women. A broad range of laboratory tests was performed for each patient. The causes of anaemia were consequently determined by two independent observers based on the laboratory results.


RESULTS
Of the 3324 included patients, 249 (7.5 %) displayed a macrocytic anaemia and were subsequently analysed. An underlying explanation could be established in 204 patients (81.9 %) with 27 patients (13.2 %) displaying multiple causes. Classic aetiology (i.e. alcohol abuse, vitamin B12/folic acid deficiency, haemolysis and possible bone marrow disease) was found in 115 patients. Alternative causes (i.e. anaemia of chronic disease, iron deficiency, renal anaemia and other causes) were encountered in 101 patients. In addition, a notable finding was the median gamma GT of 277 U/L in patients diagnosed with alcohol abuse (N = 24, IQR 118.0-925.5) and 23 U/L in the remaining cohort (N = 138, IQR 14.0-61.0). The distribution of gamma GT values was statistically different (P < 0.001). Five year survival rates were determined for six categories of causes, ranging from 39.9 % (95 % CI 12.9-66.9) for renal anaemia to 76.2 % (95 % CI 49.4-103.0) for the category multiple causes.


CONCLUSION
In addition to classic explanations for macrocytosis, alternative causes are frequently encountered in patients with macrocytic anaemia in general practice.
['Stouten|Karlijn|K|', 'Riedl|Jurgen A|JA|', 'Droogendijk|Jolanda|J|', 'Castel|Rob|R|', 'van Rosmalen|Joost|J|', 'van Houten|Ron J|RJ|', 'Berendes|Paul|P|', 'Sonneveld|Pieter|P|', 'Levin|Mark-David|MD|']
D000368:Aged D000369:Aged, 80 and over D000437:Alcoholism D018798:Anemia, Iron-Deficiency D000748:Anemia, Macrocytic D001855:Bone Marrow Diseases D058006:General Practice D006461:Hemolysis D006801:Humans D007674:Kidney Diseases D008875:Middle Aged D009426:Netherlands D015995:Prevalence D015996:Survival Rate D014806:Vitamin B 12 Deficiency D005723:gamma-Glutamyltransferase
Macrocytic anaemia General practice Survival Erythrocytes Erythropoiesis Laboratory markers