Adults with iron deficiency without anaemia face a measurable risk of serious gastrointestinal disease and neoplasia, according to findings from a retrospective study conducted between January 2023 and June 2025 at the Gastroenterology Clinic of Ankara Etlik City Hospital, Türkiye, requiring individualized clinical evaluation.
Findings in Patients With and Without Anaemia
The investigation evaluated clinical variables associated with gastrointestinal findings by examining 1,160 adults who underwent both upper gastrointestinal endoscopy and colonoscopy following laboratory confirmation of iron deficiency. Among these participants, 553 individuals presented with iron deficiency without anaemia, while 607 patients had iron deficiency anaemia.
Clinically significant gastrointestinal lesions appeared more frequently in the anaemia group than in patients without anaemia, affecting 22.1% and 10.7% of patients respectively, a statistically significant difference. A comparable pattern emerged for gastrointestinal neoplasia, which was documented in 11.0% of patients with iron deficiency anaemia compared with 5.8% of those without anaemia.
Total gastrointestinal malignancy was also more prevalent among individuals with anaemia, touching 6.6% compared with 2.2% in the non-anaemia group.
Within the group without anaemia, male sex emerged as the sole independent clinical variable associated with gastrointestinal neoplasia, establishing a potential factor for risk assessment even though the research did not determine that sex alone should dictate whether an endoscopy is performed.
Further consideration of patient specific risk factors may help guide decisions about investigation in this population, as noted by researchers Yıldırım and Deniz in their published work.
Risk Stratification and Surgical Outcomes in Colorectal Cancer
Beyond diagnostic endoscopy, iron metabolism disorders carry severe implications for patients facing surgical intervention. A prospective observational study investigated geriatric patients scheduled for elective laparoscopic colorectal cancer surgery, evaluating preoperative frailty using the Edmonton Frail Scale, a 17-point multidimensional instrument assessing cognitive, functional, physical, nutritional, and psychosocial domains.
Among 120 patients aged 65 years or older, anaemia was present in half of the cohort, while iron deficiency anaemia affected 34.2% of patients.
Edmonton Frail Scale scores were markedly higher in patients with iron deficiency anaemia, and this association persisted even after researchers adjusted for age and the Charlson Comorbidity Index.
Postoperative complications proved considerably more frequent in the iron deficiency anaemia group, reaching 46.3% compared with 7.6% among non-affected patients.
Anemic patients without iron deficiency did not differ from non-anemic patients in their frailty scores, early recovery measures, or intensive care unit lengths of stay, indicating that iron deficiency itself drives the elevated vulnerability rather than low hemoglobin alone.
The Edmonton Frail Scale discriminated postoperative complications effectively, with an area under the curve of 0.807, and an Edmonton Frail Scale score of 6.5 or greater showed a strong association with complications in the prespecified model, yielding an odds ratio of 4.51. This association was somewhat attenuated after adjustment for comorbidity burden.
Global Context and Dietary Factors Influencing Iron Metabolism
Iron metabolism disorders intersect broadly with public health and oncology. Colorectal cancer represents the third most common cancer worldwide, carrying substantial global incidence and mortality burdens, as noted in the Chinese Medical Journal. Iron deficiency anaemia acts as a frequent extraintestinal symptom of colorectal cancer that can precede formal diagnosis by up to two years, functioning as an early diagnostic marker and prognostic indicator.
Recent scientific literature has also provided compelling mechanistic insights into how iron operates inside oncological pathways. Investigators have demonstrated that iron is involved in colorectal cancer development through its promotion of human telomerase reverse transcriptase and telomerase reactivation, which represents a biological mechanism that cancer cells use to maintain telomere length and achieve unlimited replication.
Dietary patterns influence these pathways. Because the colorectal epithelium is directly exposed to iron, managing the intake of dietary iron is a vital strategy for prevention.
The collective evidence demonstrates that a normal haemoglobin count does not rule out serious pathology. Clinicians must weigh individual risk factors rather than relying exclusively on the presence or absence of anaemia when deciding whether to pursue endoscopic investigations.
Restoring iron levels carefully through supplementation while monitoring ferritin and transferrin saturation is a clinical goal, though erythropoiesis-stimulating agents must be used with caution to avoid stimulating tumor growth.
Whether sex alone should dictate whether an endoscopy is performed remains undetermined by the research, leaving open how clinicians should weigh male sex as the sole independent clinical variable associated with gastrointestinal neoplasia within the group without anaemia.