Can non-invasive haemoglobin measurement triage for expedited colonoscopy? An exploratory study

Colonoscopy is the most common diagnostic procedure for colorectal cancer (CRC). However, limited resources and increased demand have led to prolonged waiting times. Given that anaemia is a symptom of CRC, this exploratory study aimed to evaluate whether a non-invasive haemoglobin measurement (NHM) device could be used to triage patients for earlier colonoscopy.
Patients scheduled for index colonoscopy were recruited and had their NHM recorded once before colonoscopy. Patients with previous colorectal surgery, radiologically-proven colorectal pathology, anaemia and those having impediments to accurate NHM readings were excluded from the study. Post-colonoscopy outcomes were collected.
CRC and polyp prevalence was at 2.3% and 57.9% respectively in our sample of 221 patients. Mean haemoglobin (Hb) probe readings were within the non-anaemic range of 14.87 SpHb g/dL for males and 12.94 SpHb g/dL for females. NHM Hb values were not significantly associated with polyp presence or CRC from colonoscopy. There was also no difference in mean HNM Hb values between patients with or without CRC/polyps.
Use of a novel NHM device to identify potential anaemic patients for earlier colonoscopy seems unfeasible. This might be because anaemia is an undifferentiated symptom associated but not exclusive to CRC, or the variable prevalence of anaemia in CRC populations (11.0-57.0%). Future studies could examine the use of NHM for other CRC settings, including inpatient monitoring of Hb.