Quality of life and its association with irritable bowel syndrome and fatigue ten years after giardiasis

BACKGROUND: Gastroenteritis has been associated with complications such as irritable bowel syndrome (IBS) and chronic fatigue (CF). Little is known about the implications for quality of life (QoL) in this setting. The aims of this study were to evaluate the association between exposure to Giardia infection and QoL ten years after the infection, and how this related to IBS and CF. METHODS: We followed 1252 patients with laboratory‐verified Giardia lamblia infection and a matched control group for 10 years after an epidemic in Bergen, Norway, in 2004. The main outcome was QoL after ten years as defined by the Short‐form 12 version 2 with a physical component summary (PCS) and a mental component summary (MCS), both with range 0‐100 (T‐score). Regression analyses were performed using mixed modeling. KEY RESULTS: Mean PCS T‐score in the exposed group (51.4; 95% CI: 50.6‐52.1) was 2.8 T‐score points (95% CI: −3.8 to −1.9, P < 0.001) lower than that in the control group (54.2; 95% CI: 53.7‐54.8). The mean MCS T‐score was also 2.8 T‐score points (95% CI: −3.8 to −1.9, P < 0.001) lower among the exposed (48.9; 95% CI: 48.2‐49.6) than the controls (51.7; 95% CI: 51.1‐52.4). Further analyses found that the effect of Giardia exposure on QoL was mediated by IBS and CF. CONCLUSIONS & INFERENCES: Exposure to Giardia infection was associated with a lower QoL ten years later as compared to a control group, an effect that was mediated by IBS and CF.