Iron deficiency without anaemia is associated with reduced grip strength but not selfreported fatigue in people with crohn's in remission

Introduction

Iron deficiency anaemia (IDA) is associated with worse quality of life in inflammatory bowel disease (IBD) so treatment is advised when detected, but the impact of iron deficiency without anaemia (IDWA) is less clear so may go undetected and untreated in routine clinical care. We aimed to determine the relationship between the presence of IDWA with patient-reported outcome measures (PROMs), fatigue and grip strength in a cohort of people with CD in clinical remission.

Methods

202 CD patients in clinical remission (calprotectin <250ug/g and Harvey Bradshaw Index <5) were recruited at a single centre. Anaemia was defined as Hb <130g/L in males and <120g/L in females. Iron deficiency was defined by at least one of: ferritin < 11µg/L in females, <24µg/L in males or <100µg/L when CRP >8mg/L, transferrin saturation < 16% or soluble transferrin receptor/ferritin Index > 14. Self-reported fatigue was determined by FACIT-F. Health-related quality of life was measured using the SF36, generating a sub-score for Physical Function (SF36-PF). Grip strength was determined using Jamar® hand dynamometry.

Results

Complete data was available in 190 cases. 15 cases with anaemia (6 IDA) were excluded from the subsequent analysis. of the remaining 175, IDWA was detected in 34 (19.4%) cases with more IDWA in women than men (n= 24/91, 26.37% vs 10/84, 11.9%; p=0.026 Chi²). Self-reported severe fatigue, defined as FACIT-F <30, was present in 47 (26.9%) cases with a trend towards being more prevalent in women than men (n= 29/91, 31.9% vs 18/84, 21.4%; NS). The presence of IDWA when analysed according to gender was not associated with a lower FACIT F score (40 vs 36 in women and 40 vs 41 in men, NS) or SF36-PF score (80 vs 90 in women and 90 vs 95 in men, NS) than those without iron deficiency. IDWA was associated with a lower grip strength (26.5 vs 30.0kg p= 0.03 in women and 43.5 vs 50.0kg p=0.04 in men).

Conclusions

In this cohort of patients with CD in clinical remission, there were significant numbers of patients with iron deficiency and self-reported severe fatigue. IDWA was not associated with either self-reported fatigue or reduced physical functioning but was associated with lower grip strength, indicating a possible difference between objective and subjective assessments. These findings may guide decisions regarding the detection and treatment of IDWA in clinical practice, but further objective measures and intervention studies are required to determine whether there are treatment opportunities to improve physical function and quality of remission.