Iron Deficiency, Depression, and Other Affective Disorders in Female State Fair Attendees

Iron deficiency affects nearly 2 billion people globally, and it is among the most common risk factors for disability and death. In its most extreme presentation, it results in anemia, where the RBC count of the individual is markedly low, hindering oxygen transport. Anemia has a remarkable global presence, affecting approximately one third of the world's population. Though there are multiple causes for anemia, the World Health Organization (WHO) estimates that the most common cause for anemia on the planet is iron deficiency. Although findings from the US indicate that iron deficiency is less prevalent than in many other nations, iron deficiency is still a pervasive national public health concern. A study that analyzed the National Health and Nutrition Examination Survey (NHANES) data from 2007-2010 indicated that US children 5 years of age and younger have an anemia incidence of 3.2 percent.

Incidence of depression varies based on diagnostic tools used and categories included, as well as the country, gender, age, and socioeconomic status of individuals. Globally, it is estimated that between 4 and 10 percent of people experience major depressive disorder (MDD) while between 2.5 and 5 percent experience dysthymia, a depression that involves less severe symptoms but has a chronic manifestation. On average, the first onset of depression is 20 years old, though this figure is highly variable. It has consistently been demonstrated that females experience a much higher incidence of depression than males. MDD has repeatedly been reported in females at rates 1.5 to 3 times that of males, and female dysthymia has been reported at 2 times that of males.

The current state of the literature on the connection between mental health and iron status is further muddled by subjective, self-reported assessments and a lack of randomized controlled trials, but the evidence certainly suggests an association. Affective characteristics studied in relation to iron deficiency include irritability, anger, or mood; depression, both as postpartum depression (PPD) or depression independently; and perceived QOL. Differences in assessment tools as well as length and dosage of iron treatment likely play a pivotal role in discordant results. Most studies also include fatigue as a primary outcome as it is closely tied to these affective characteristics.

The aim of this study is to further investigate iron status and iron deficiency symptoms in menstruating females. It builds on the existing research for use of cutoff values for various biochemical assessments of iron as well as for stages of deficiency in which symptoms are experienced. In addition, the association between iron status, measured either biochemically or by self-reported iron deficiency symptoms, and depression was examined.