Predictors of iron-deficiency anemia in primary care older adults: a real-world European multi-country longitudinal study

Background: Iron deficiency is a major cause of anemia in older people. Increasing the knowledge on the predictors of iron-deficiency anemia (IDA) may facilitate its timely diagnosis. Aim: To investigate the predictors of IDA in older people in four European countries. Design and Setting: Retrospective longitudinal study. Primary care patients aged 65 or older (N = 24,051) in four European countries. Methods: IDA predictors were estimated using multivariate Cox regression based on information gathered from national primary care databases: Italy (years 2002–2013), Belgium, Germany and Spain (years 2007–2012). Adjusted hazard ratios (aHR) with 95% confidence intervals (CIs) were estimated. Results: In Spain and Belgium, men were at greater risk of IDA than women, while they had a lower risk in Italy. Weakness, irritability, alopecia and xerostomia were signs and symptoms significantly associated with IDA. Concurrent diseases, potential causes of anemia, positively associated with IDA were small bowel polyposis, stomach cancer, obesity, gastritis and peptic ulcer, esophagitis, Crohn’s disease, celiac disease, lymphangiectasis, gastrectomy or gastric atrophy, gut resection or bypass, and cardiac prosthetic valve. Aspirin users had a 12–35% higher hazard of IDA than non-users. Similarly, corticosteroids and anti-acids were positively associated with IDA. A higher level of comorbidity was associated with an increased hazard of IDA in all countries. Conclusions: Specific signs and symptoms, chronic conditions, a greater comorbidity burden, and specific pharmacological treatments registered in primary care databases represent relevant predictors and correlates of incident IDA in older people in Europe. General practitioners might employ this information to obtain early diagnosis of IDA in community-dwelling older adults.