'Physical or psychological?' - a comparative study of causal attribution for chronic fatigue in Brazilian and British primary care patients

Objective: Causal attribution influences symptom experience, help-seeking behaviour and prognosis in chronic fatigue syndrome. We compared causal attribution of patients with unexplained chronic fatigue (UCF) in Brazil and Britain. Method: Primary care attenders in Sao Paulo (n = 3914) and London (n = 2459) were screened for the presence of UCF. Those with UCF (Sao Paulo n = 452; London n = 178) were assessed for causal attribution (physical vs. psychosocial), perceived chronicity (i.e. reported duration of fatigue) and disability. Results: British UCF patients were more likely to attribute their fatigue to physical causes (adjusted odds ratio 1.70, P = 0.037) and perceived their fatigue to be more chronic (adjusted beta 0.15, P = 0.002). There was no significant difference in current disability (adjusted beta -0.01, P = 0.81). Conclusion: Despite similar disability levels, UCF patients in different cultural settings presented different attributions and perceptions about their illness. Sociocultural factors may have an important role in shaping illness attribution and perception around chronic fatigue.