Prevalence of Iron Deficiency (ID) without anemia in the general population presenting to primary care clinics: a cross-sectional study

Objectives: There are no evidence-based recommendations to screen for iron deficiency in non-anemic patients, even though symptoms may be present. The aim of this study is to measure the prevalence of iron deficiency (ID) without anemia in the general population aged 18-50 presenting to primary care along with the incidence and time to develop anemia in the iron-deficient population. Methods: A single-center retrospective chart review of patients who presented to family medicine clinics between June 2010 and March 2018 at the American University of Beirut Medical Center (AUBMC). Adults 18-50 years old, who had a CBC and ferritin levels ordered with the proximity of maximum four weeks, with an absence of current or previously documented anemia (back to 2007) defined as MCV less than 80 or hemoglobin (Hb) less than 12 in females and 13 in males were included. ID was defined as serum ferritin level below 30 ng/mL. Results: A total of 1,784 adults aged 18-50 years were included. The prevalence of iron deficiency without anemia was 57.5% [95% confidence interval, 55.08% to 59.92%] among females and 7.6% [95% confidence interval, 3.77% to 11.43%] among males. Iron deficiency without anemia was significantly associated with the level of hemoglobin (Hb) among females (Chi-square, p < 0.001). Overt iron deficiency anemia developed within the 5 years follow up in 14% of females and 0.5% of males. There was a statistically significant association between iron deficiency and menorrhagia (Chi-square, P-value = 0.004), dizziness (Chi-square, P-value = 0.018), dyspnea/shortness of breath (Chi-square, P-value = 0.020), polycystic ovarian syndrome (Chi-square, P-value = 0.0256) and rheumatoid arthritis (Chi-square, P-value = 0.00278). Conclusion: Iron deficiency without anemia in childbearing females is common but only one-seventh of females developed anemia within 5 years. Guidelines should consider incorporating ferritin levels with CBC in the workup of patients presenting with symptoms suggestive of iron deficiency or anemia.