Colonoscopy first for iron-deficiency anaemia: a Numbers Needed to Investigate approach

Prediction of Gastrointestinal Tract Cancers Using Longitudinal Electronic Health Record Data

BACKGROUND

Luminal gastrointestinal (GI) tract cancers, including esophageal, gastric, small bowel, colorectal, and anal cancers, are often diagnosed at late stages. These tumors can cause gradual GI bleeding, which may be unrecognized but detectable by subtle laboratory changes. Our aim was to develop models to predict luminal GI tract cancers using laboratory studies and patient characteristics using logistic regression and random forest machine learning methods.

METHODS

The study was a single-center, retrospective cohort at an academic medical center, with enrollment between 2004-2013 and with follow-up until 2018, who had at least two complete blood counts (CBCs). The primary outcome was the diagnosis of GI tract cancer. Prediction models were developed using multivariable single timepoint logistic regression, longitudinal logistic regression, and random forest machine learning.

RESULTS

The cohort included 148,158 individuals, with 1025 GI tract cancers. For 3-year prediction of GI tract cancers, the longitudinal random forest model performed the best, with an area under the receiver operator curve (AuROC) of 0.750 (95% CI 0.729-0.771) and Brier score of 0.116, compared to the longitudinal logistic regression model, with an AuROC of 0.735 (95% CI 0.713-0.757) and Brier score of 0.205.

CONCLUSIONS

Prediction models incorporating longitudinal features of the CBC outperformed the single timepoint logistic regression models at 3-years, with a trend toward improved accuracy of prediction using a random forest machine learning model compared to a longitudinal logistic regression model.

Testing Practices, Interpretation, and Diagnostic Evaluation of Iron Deficiency Anemia by US Primary Care Physicians

IMPORTANCE

Recognition of iron deficiency anemia (IDA) is important to initiate timely evaluation for gastrointestinal tract cancer. Retrospective studies have reported delays in diagnostic evaluation of IDA as a common factor associated with delayed diagnosis of colorectal cancer.

OBJECTIVE

To assess how US primary care physicians (PCPs) approach testing for anemia, interpret iron laboratory studies, and refer patients with IDA for gastrointestinal endoscopy.

DESIGN, SETTING, AND PARTICIPANTS

This survey study, conducted in August 2019, included members of the American College of Physicians Internal Medicine Insiders Panel, a nationally representative group of American College of Physicians membership, who self-identified as PCPs. Participants completed a vignette-based survey to assess practices related to screening for anemia, interpretation of laboratory-based iron studies, and appropriate diagnostic evaluation of IDA.

MAIN OUTCOMES AND MEASURES

Descriptive statistics based on survey responses were evaluated for frequency of anemia screening, correct interpretation of iron laboratory studies, and proportion of patients with new-onset IDA referred for gastrointestinal tract evaluation.

RESULTS

Of 631 PCPs who received an invitation to participate in the survey, 356 (56.4%) responded and 31 (4.9%) were excluded, for an adjusted eligible sample size of 600, yielding 325 completed surveys (response rate, 54.2%). Of the 325 participants who completed surveys, 180 (55.4%) were men; age of participants was not assessed. The mean (SD) duration of clinical experience was 19.8 (11.2) years (range, 1.0-45.0 years). A total of 250 participants (76.9%) screened at least some patients for anemia. Interpretation of iron studies was least accurate in a scenario of a borderline low ferritin level (40 ng/mL) with low transferrin saturation (2%); 86 participants (26.5%) incorrectly responded that this scenario did not indicate IDA, and 239 (73.5%) correctly identified this scenario as IDA. Of 312 participants, 170 (54.5%) recommended bidirectional endoscopy (upper endoscopy and colonoscopy) for new IDA for women aged 65 years; of 305 respondents, 168 (55.1%) recommended bidirectional endoscopy for men aged 65 years.

CONCLUSIONS AND RELEVANCE

In this survey study, US PCPs' self-reported testing practices for anemia suggest overuse of screening laboratory tests, misinterpretation of iron studies, and underuse of bidirectional endoscopy for evaluation of new-onset IDA. Both misinterpretation of iron studies and underuse of bidirectional endoscopy can lead to delayed diagnosis of gastrointestinal tract cancers and warrant additional interventions.

Prevalence of Appropriate Testing for Incident Anemia in the US Department of Veterans Affairs

This cohort study assesses the prevalence of appropriate testing for incident anemia in a large cohort from a national integrated health care system.

Efficacy of Gastrointestinal Endoscopy in 398 Patients With Iron Deficiency Anemia Who Lack Gastrointestinal Symptoms: Basrah Experience

Introduction

The diagnosis of iron deficiency anemia (IDA) relies heavily on symptom presentation, and patients lacking typical gastrointestinal (GI) symptoms represent a diagnostic challenge. IDA may be the initial manifestation of underlying pathology. This study sought to evaluate the effectiveness of different GI endoscopic studies in patients with IDA who lack GI symptoms.

Methods

We conducted an observational, multicenter retrospective analysis of 398 asymptomatic IDA patients admitted for GI endoscopic diagnosis from 2006 to 2016. Baseline measurements included hemoglobin, serum ferritin, mean corpuscular volume, serum iron, total iron-binding capacity, and transferrin saturation. We analyzed demographic characteristics, duration of hospital stay, the degree of severity of anemia, and endoscopic findings.

Results

The mean age of the study population was 52±9 years (range, 23 to 85 years), and 53% were men. Most patients were older than 45 years (n=353, 89%) with mild to moderate IDA. Patients underwent esophagogastroduodenoscopy (EGD, n=102), colonoscopy (n=271), or bidirectional endoscopy (n=25). The mean hospital stay was 2.72±1.66 days. The most common EGD results were atrophic gastritis (n=31), peptic ulcer (n=25), and negative findings (n=25). The most common colonoscopic results were negative findings (n=118), nonspecific colonic inflammatory changes (n=117), and non-bleeding hemorrhoids (n=29). We found no significant association between any endoscopic findings and age, gender, the severity of anemia, and length of hospitalization.

Conclusions

The presence of symptoms is of limited value in guiding diagnostic procedures concerning GI etiologies. Asymptomatic patients with IDA patients should receive an endoscopic examination irrespective of iron parameters, age, or gender for potentially treatable pathologies, especially for patients with suspected malignancies.

Predictors of serious findings on bi-directional endoscopy in young patients with anemia and GI symptoms

Background and Objective:

Iron deficiency anemia (IDA) has been cited as the most common cause of anemia globally. Gastrointestinal (GI) lesions are amongst the common cause of IDA. Endoscopic evaluation is the most effective way to investigate the IDA. The aim of this study was to show the association of alarming GI symptoms with abnormal endoscopic findings and to cut off the burden and cost of unnecessary endoscopies.

Methods:

This is cross sectional study of anemic patient who underwent upper and lower GI endoscopies in Aga Khan University Hospital, Karachi between July-December 2016.

Results:

Total 243 patients were identified after excluding ineligible patients. The mean age of subjects was 31.9 ± 6.1 years with a slight over-representation of females (57.4%). 149 (61.31%) patients underwent only upper GI endoscopic evaluation, and 83 (34.15%) patients on whom bi-directional endoscopy was performed (upper and lower). The remaining 11 (4.52%) patients underwent colonoscopy only. 16 (6.6%) subjects had negative findings on evaluation, while gastritis and serious findings were observed in 175 (72.0%) and 52 (21.4%) patients respectively. We found that patients with alarm features such as dysphagia (aOR: 2.07, 95%CI: 0.12-34.1), altered bowel habits (aOR: 1.64, 95%CI: 0.44-6.09) and weight loss (aOR: 1.25 95%CI: 0.54-2.85) demonstrated higher odds of serious findings on endoscopic evaluation as compared to the reference category, however they were not independently associated.

Conclusion:

Most of our patients had non-malignant pathologies, while alarm features were not found to be useful predictors of serious findings.

The difference in endoscopic yield in patients with either iron-deficiency anemia or anemia with normal ferritin

OBJECTIVE

Current guidelines recommend a gastroduodenoscopy (GDS) and colonoscopy in patients with iron-deficiency anemia (IDA). However, in daily practice, patients with nonferriprive anemia are also referred for endoscopy. The aim of this study is to compare the diagnostic yield of colonoscopy and GDS in patients with IDA and non-IDA.

PATIENTS AND METHODS

A retrospective single-center cohort study was carried out from January 2013 till February 2016 that included 917 patients with anemia. We compared the endoscopic yield in patients with IDA versus patients with anemia otherwise. Multivariate regression analyses were carried out to identify predictive factors for the diagnostic yield of GDS and colonoscopy.

RESULTS

The yield of both GDS (25%) and colonoscopy (30%) was comparable in IDA and non-IDA patients. However, in patients without known gastrointestinal medical history and without concomitant indications for endoscopy (N=373), the diagnostic yield of GDS was three times higher in IDA patients compared with non-IDA patients (P<0.01). The diagnostic yield for colonoscopy was not significantly different between the two groups. Age and sex were recurrent predictive variables in the outcome of both GDS and colonoscopies.

CONCLUSION

We recommend IDA as well as non-IDA as indications for GDS and colonoscopy. Only in patients without gastrointestinal history or localizing complaints a significant difference in the diagnostic yield is found between IDA and non-IDA patients. In this group, upper endoscopy can be omitted in non-IDA patients as they were three times less likely to have a bleeding source found on GDS compared with IDA patients.

Practical gastrointestinal investigation of iron deficiency anaemia

About 10% of oesophagogastroduodenoscopies (OGDs) and colonoscopies are done for investigation of iron deficiency anemia (IDA) . Much of the existing guidance on investigation of IDA predates CRC screening, which has driven significant improvements in colonoscopy quality and completion rates, as well as a reduction in Helicobacter pylori prevalence and increase in PPI usage, and therefore probably needs re-consideration. New investigations, e.g. CT colonography, enteroscopy and capsule endoscopy have also been introduced. Areas covered: This review updates the approach to practical investigation of IDA. Medline was searched using the terms iron deficiency AND anemia AND/OR gastroscopy, colonoscopy, capsule and enteroscopy, together with review of recent relevant published abstracts on the topic. Expert commentary: Gastrointestinal pathology is now a more common cause of IDA than upper GI causes, reflecting better colonoscopy accuracy and completion rates as well as changing disease patterns, and carcinomas are more likely cause IDA than benign adenomas. Increasing use of antiplatelet and anticoagulants is driving greater presentation of IDA. Capsule endoscopy, enteroscopy and CT colonography are increasingly used. Fecal occult blood testing may be a useful simple screening method in the frail, as a negative test can avoid the need for invasive tests.

Outcome of endoscopy-negative iron deficiency anemia in patients above 65: A longitudinal multicenter cohort

After the age of 65 years, iron deficiency anemia (IDA) requires the elimination of digestive neoplasia and is explored with upper and lower gastrointestinal (GI) endoscopy. However, such explorations are negative in 14% to 37% of patients. To further evaluate this issue, we evaluated the outcomes of patients aged over 65 years with endoscopy-negative IDA.We retrospectively analyzed the outcomes of in-patients over the age of 65 years with IDA (hemoglobin <12 g/dL and ferritin <70 μg/L) who had negative complete upper and lower GI endoscopies in 7 tertiary medical hospitals. Death, the persistence of anemia, further investigations, and the final diagnosis for IDA were analyzed after at least 12 months by calling the patients' general practitioners and using hospital records.Between 2004 and 2011, 69 patients (74% women) with a median age of 78 (interquartile range (IQR) 75-82) years and hemoglobin and ferritin levels of 8.4 (IQR 6.8-9.9) g/dL and 14 (IQR 8-27) μg/L, respectively, had endoscopy-negative IDA, and 73% of these patients received daily antithrombotics. After a follow-up of 41 ± 22 months, 23 (33%) of the patients were dead; 5 deaths were linked with the IDA, and 45 (65%) patients had persistent anemia, which was significantly associated with death (P = 0.007). Further investigations were performed in 45 patients; 64% of the second-look GI endoscopies led to significant changes in treatment compared with 25% for the capsule endoscopies. Conventional diagnoses of IDA were ultimately established for 19 (27%) patients and included 3 cancer patients. Among the 50 other patients, 40 (58%) had antithrombotics.In endoscopy-negative IDA over the age of 65 years, further investigations should be reserved for patients with persistent anemia, and second-look GI endoscopy should be favored. If the results of these investigations are negative, the role of antithrombotics should be considered.

Role of faecal occult bloods in the diagnosis of iron deficiency anaemia

OBJECTIVE

To determine whether faecal occult blood (FOB) testing in patients with iron deficiency anaemia (IDA) can predict the presence of gastrointestinal cancer.

DESIGN

Cohort study.

SETTINGS

Single secondary care hospital UK.

PATIENTS

All individuals aged 20 years and older referred for the investigation for IDA.

INTERVENTIONS

Data was collected from all the patients regarding haemoglobin (Hb), mean corpuscular volume, age, sex, symptomatology and medication. All patients had FOB tests using laboratory guaiac and haemocell methods, and then underwent gastroscopy and colonoscopy.

MAIN OUTCOME MEASURES

Accuracy, sensitivity and specificity of FOBs for identifying cancer in the upper or lower gastrointestinal tract.

RESULTS

In total, 292 patients completed the study; 37 patients were diagnosed with carcinoma (colon 34, gastro-oesophageal 3). Using an optimal combination of lab guiaic and haemocell test resulted in just one colorectal cancer being missed, a sensitivity of 97%, specificity of 49% and negative predictive value of 99%. The test was less effective for upper gastrointestinal cancer, with 2/3 tumours missed by the tests.

CONCLUSIONS

Patients who have negative FOB tests are very unlikely to have a colorectal cancer, and the benefits to further colonic investigation is limited. This should be carefully considered in patients with significant comorbidities, where the risks of investigation may outweigh the benefits.

Symptoms and signs in patients with colorectal cancer

The symptoms and signs of colorectal cancer vary from the general population to primary care and in the referred population to secondary care. This review aims to address the diverse symptoms, signs and combinations with relevance to colorectal cancer at various points in the diagnostic pathway and tries to shed light on this complex and confusing area. A move towards a lower threshold for referral and increased use of diagnostics might be a more reliable option for early diagnosis.

Treatment of iron deficiency anemia associated with gastrointestinal tract diseases

The gastrointestinal (GI) tract is a common site of bleeding that may lead to iron deficiency anemia (IDA). Treatment of IDA depends on severity and acuity of patients’ signs and symptoms. While red blood cell transfusions may be required in hemodynamically unstable patients, transfusions should be avoided in chronically anemic patients due to their potential side effects and cost. Iron studies need to be performed after episodes of GI bleeding and stores need to be replenished before anemia develops. Oral iron preparations are efficacious but poorly tolerated due to non-absorbed iron-mediated GI side effects. However, oral iron dose may be reduced with no effect on its efficacy while decreasing side effects and patient discontinuation rates. Parenteral iron therapy replenishes iron stores quicker and is better tolerated than oral therapy. Serious hypersensitive reactions are very rare with new intravenous preparations. While data on worsening of inflammatory bowel disease (IBD) activity by oral iron therapy are not conclusive, parenteral iron therapy still seems to be advantageous in the treatment of IDA in patients with IBD, because oral iron may not be sufficient to overcome the chronic blood loss and GI side effects of oral iron which may mimic IBD exacerbation. Finally, we believe the choice of oral vs parenteral iron therapy in patients with IBD should primarily depend on acuity and severity of patients’ signs and symptoms.

Iron status and colorectal cancer in symptomatic elderly patients

OBJECTIVE

The study aim is to determine the relationship between the prevalence of colorectal cancer and iron status in elderly anemic and non-anemic patients.

METHODS

We retrospectively investigated 359 consecutive elderly patients, aged 70 years and more, who presented to a geriatric department and who underwent a total colonoscopy. The histopathologic diagnosis of colorectal carcinoma was the primary outcome measure, and its presence was compared with the iron status, evaluated by serum ferritin and hemoglobin levels.

RESULTS

Less than half of the patients with colorectal carcinoma had iron-deficiency anemia. The prevalence of colorectal carcinoma was similar among patients with a serum ferritin level less than 50 microg/L (16%), between 50 and 100 mirog/L (20%), and greater than 100 microg/L (13%), and was not different between anemic and non-anemic patients. Sex (odds ratio for men 2.1; 95% confidence interval [CI], 1.2-3.9) and increasing age (6.6% per year; 95% CI, 1.2-12.4), but not hemoglobin and serum ferritin, were independent risk factors for colorectal carcinoma. Those with a proximal colorectal carcinoma had a lower hemoglobin and ferritin level and a higher prevalence of iron-deficiency anemia compared with patients with a distal colorectal carcinoma.

CONCLUSION

The prevalence of colorectal carcinoma is high in anemic and non-anemic elderly symptomatic patients, irrespective of the iron status. Therefore, the decision to order a colonoscopy in older patients should not only be considered in patients with anemia or iron deficiency but also in patients with suspicious symptoms without anemia or iron deficiency.

Predictors of gastrointestinal lesions on endoscopy in iron deficiency anemia without gastrointestinal symptoms

BACKGROUND

Iron deficiency anaemia (IDA) due to occult gastrointestinal (GI) blood loss usually remains unnoticed until patient become symptomatic. There is sparse data in IDA patients without gastrointestinal symptoms. This study was designed to find out the frequency and predictors of endoscopic lesions in IDA without gastrointestinal symptoms. Cross-sectional study performed on a convenience sample of consecutive subjects.

METHODS

Ninety five consecutive patients with laboratory based diagnosis of IDA having no gastrointestinal symptoms were interviewed and their clinical and biochemical variables were recorded. All the study patients underwent esophago-gastroduodenoscopy (EGD) and colonoscopy. Endoscopic findings were documented as presence/absence of bleeding related lesion and presence/absence of cause of IDA. Multiple logistic regressions were performed to identify variables significantly related to outcome variables.

RESULTS

Possible cause of anaemia was found in 71% and bleeding related lesions were found in 53% of patients. Upper gastrointestinal tract lesions were found in 41% of patients with bleeding related lesions. On multivariable logistic regression; advancing age, low mean corpuscular volume (MCV Collapse

Key Words Collapse

MESH Headings

• Adult
• Age Factors
• Aged
• Anemia, Iron-Deficiency/etiology
• Cross-Sectional Studies
• Endoscopy, Digestive System
• Erythrocyte Indices
• Female
• Gastrointestinal Diseases/complications
• Gastrointestinal Diseases/diagnosis
• Gastrointestinal Hemorrhage/complications
• Gastrointestinal Hemorrhage/diagnosis
• Humans
• Logistic Models
• Male
• Middle Aged
• Occult Blood
• Predictive Value of Tests

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Grants Collapse

Affiliation(s)

Shahid Majid Section of Gastroenterology, Department of Medicine, Aga Khan University Hospital, Karachi, Pakistan
Mohammad Salih Section of Gastroenterology, Department of Medicine, Aga Khan University Hospital, Karachi, Pakistan
Rozina Wasaya Section of Gastroenterology, Department of Medicine, Aga Khan University Hospital, Karachi, Pakistan
Wasim Jafri Section of Gastroenterology, Department of Medicine, Aga Khan University Hospital, Karachi, Pakistan

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Validation of the Lower Gastrointestinal Electronic Referral Protocol

Background

Recognition of people presenting to the general practitioner with symptoms suggestive of colorectal cancer varies considerably, as do the subsequent patterns of referral and treatment. The Lower Gastrointestinal Electronic Referral Protocol (e-RP) was developed to be used alongside the national Choose and Book programme. This paper addresses the validation of the e-RP.

Methods

The e-RP was validated using three datasets: 100 consecutive patients with colorectal cancer, 100 2-week wait (TWW) suspected cancer referrals and 100 routine referrals. The actual destination of referred patients, their clinical diagnosis and referral urgency were compared with destination and referral urgency assigned by the e-RP.

Results

Some 43·0 per cent of patients with colorectal cancer were actually referred through the TWW system and the e-RP successfully upgraded 85·0 per cent of these patients as TWW referrals (Pearson χ2 = 9·76, 1 d.f., P = 0·002). The e-RP also redirected three of four patients with colorectal cancer in routine referrals to TWW clinics. Right-sided cancers were appropriately directed to colonoscopy as the first contact in secondary care or to outpatients for investigation of a palpable mass. Most patients with left-sided cancers were directed to flexible sigmoidoscopy clinics.

Conclusion

A dedicated referral protocol addressing all colorectal symptoms would significantly improve the overall yield of colorectal cancers through the TWW route and reduce delays in patient pathways with ‘straight to test’ in secondary care.