Self–reported fatigue and Quality of Life (QOL) in adult patients with cystic fibrosis
- N S Gale
- C E Bolton (Respiratory Medicine, Cardiff University)
- A Prossor (Adult CF Centre, Llandough Hospital, Penarth, Wales)
- Dr Stephanie Enright
- R I Ketchell (Adult CF Centre, Llandough Hospital, Penarth, Wales)
- D J Shale (Respiratory Medicine, Cardiff University)
Background: Fatigue is commonly reported by patients with CF. Determinants of fatigue and its links to QOL are unknown. We assessed fatigue, QOL and disease indicators in clinically stable patients.
Method: We studied 22 adults with confirmed CF (12 male), mean (SD) age 27.3(7.3) years. The Multi Dimensional Fatigue index (MFI-20)1 and the CF Quality of Life Questionnaire (CF-QOL)2 were self completed. The MFI-20 is validated in cancer and COPD, but its use in CF not explored. It utilises 20 questions (higher scores reflecting more fatigue) to determine five domains (each scored out of 20) including general and physical. Circulating interleukin-6 (IL-6) and tumour necrosis factor (TNF-α) soluble receptors (sr) I and II, albumin, CRP, spirometry, BMI and the Northern chest X-ray Score were determined.
Results: Mean (SD) FEV1% predicted was 64.2(23.8)% and BMI 23.3(3.6) kg/m2. The general fatigue score was 9.7(3.4) and physical fatigue 9.3(3.5), and the CF-QOL score 76.3(17.8)%, (higher scores indicating a better QOL), with no gender differences in either score. Systemic inflammatory status was CRP 7.94(2.51)µg/ml (n=20), IL-6 7.94(1.58)pg/ml, TNF-α srI 1258.93(1.58)pg/ml and TNF- α srII 1995.26(1.26)pg/ml, (geometric mean (SD), n=19). General (r=-0.737) and physical fatigue (r=-0.751) were related to total CF-QOL, both p<0.001. General fatigue was related to albumin (r=-0.46,p<0.05), and physical fatigue to log10CRP (r=0.47), the Northern score (r=0.47) and FEV1(l) (r=-0.43), all p<0.05, while the CF-QOL was unrelated. Patients with mild airways obstruction (FEV1>50% n=16), had higher CF-QOL scores 80.8(16.5) (p=0.05) than those with more severe airways obstruction 64.5(16.1), n=6. Physical fatigue tended to be greater (p=0.07), but not general fatigue, in more severe airways obstruction. Frequent exacerbators (>3/year), (n=8) had greater general, 11.6(2.2) vs 8.4(3.5), physical fatigue 10.9(4.4) vs 7.9(2.0) and IL-6 levels, (all p<0.05), but similar CF-QOL to those with <3 exacerbations/year.
Conclusion: Fatigue in adults with stable CF was related to QOL, but only fatigue was related to disease severity and systemic inflammation. The succinct MFI-20 may reflect more the disease process than QOL assessment. Further research is required to fully evaluate its utility.