Gender differences in determinants of iron-deficiency anemia: a population-based study conducted in four European countries.

Iron-deficiency anemia (IDA) was the main condition contributing to higher rates of years lived with disabilities in women in 2016. To date, few studies have investigated gender differences in determinants of IDA in Europe. The aim of the present study was to evaluate the determinants of IDA among females and males in four European countries. IDA determinants were estimated using multivariable Cox regression based on information gathered from national primary care databases, namely Italy (for years 2002-2013), Belgium, Germany, and Spain (for years 2007-2012). Adjusted hazard ratios (aHR) with 95% confidence intervals (CIs) were estimated. Age was significantly associated with IDA in females of childbearing age in all four countries, as well as pregnancy, for which the aHR ranged from 1.20 (95% CI 1.15-1.25) in Italy to 1.88 (95% CI 1.53-2.31) in Germany. In males, the aHR increased with age starting from the 65-69 age group. Menometrorrhagia was associated with IDA in Germany (aHR 2.71, 95% CI 1.96-3.73), Italy (aHR 1.80, 95% CI 1.60-2.03), and Spain (aHR 1.52, 95% CI 1.31-1.76). A greater risk for women with alopecia was also observed. Weakness and headache indicated a higher risk in both men and women. Patients with diseases characterized by blood loss or gastrointestinal malabsorption were also at significantly increased risk. Physicians should encourage women of childbearing age to adhere to dietary recommendations regarding iron intake and regularly prescribe screening of iron status. Upper and lower gastrointestinal investigations should be recommended for patients with a confirmed diagnosis of IDA.