The 'funnel effect' of Fibromyalgia (FM) assumes that as patients access healthcare services, they present greater severity and a more complex clinical situation than individuals with FM from the general population, but the studies comparing patients treated in different levels of healthcare are scarce. The aim of this study was to analyse the 'funnel effect' hypothesis by comparing patients from secondary and tertiary healthcare services.
A cross-sectional sample of female patients was selected in secondary (rheumatology practices - RP) and in tertiary healthcare (chronic pain clinics - CPC). Information about sociodemographic, clinical and psychological characteristics was collected and health related quality of life (HRQL) was assessed.
In total, 55 patients from RP and 60 patients from CPC were included in the comparison. Patients from CPC revealed a worst clinical status (higher number of tender points, medical visits and comorbidity), more somatic symptoms (pain and daytime dysfunction levels) and worst emotional status (more anxiety) than patients from RP. Patients attending CPC also revealed a worst HRQL than RP patients although this difference was mediated by the differences in clinical and psychological variables.
The worst clinical and psychological status and poorer quality of life in the patients from tertiary healthcare (chronic pain clinics) in relation to the patients from secondary healthcare (rheumatology practices) must be taken into account to design studies that assess any of these aspects, to a proper analysis and interpretation of the data, and to define the scope of its generalization, as data from different clinical settings are not directly comparable.
Our study supports the 'funnel effect' hypothesis among patients of different healthcare levels, with patients from tertiary healthcare services revealing worst clinical status, more somatic and psychological symptoms, and worst HRQL than patients from secondary healthcare services.