Objective: Health is a complex and multi-dimensional entity and is neither easily determined nor easily conveyed to others. Publications have often combined various variables of disease activity and health-related quality of life (HRQoL), used the variables interchangeably or utilized summation indices to compare health assessment. The aim of this study is to investigate the relationship between measurements of disease activity and HRQoL.
Study: design Cross-sectional evaluation of disease activity and HRQoL.
Study population: Two hundred and eleven consecutive patients with ulcerative colitis.
Setting: The catchment area of Linköping University Hospital.
Measurements: HRQoL was measured using two questionnaires, the Sickness Impact Profile (SIP) and the Rating Form of IBD Patient Concerns (RFIPC). Patients were also asked if they were 'feeling fit and well', as a measurement of general health perception. Disease activity was measured by means of symptom cards, laboratory tests and sigmoidoscopy.
Results: The correlations (Spearman's r (r5)) between variables of disease activity and HRQoL were low. 'Feeling fit and well' was best correlated to worries and concerns (the RFIPC, rs 0.32, P < 0.05), while there was a decreasing association with subjective functional status (the SIP, rs 0.31, P < 0.05), symptoms (stools per day, rs 0.15, not significant) and biological variables (endoscopy score, rs 0.04, not significant).
Conclusion: The correlations between traditional measurements of disease activity and various measures of HRQoL are low. We therefore propose a system whereby the process is conceptualized using a 'network strategy', ordering the measurements of disease activity and HRQoL into five dimensions: biological variables, symptoms, functional status, worries and concerns, and health perceptions. We feel that this method of interpretation more accurately reflects the overall health of a group of patients with IBD than more traditional summation indices.