BIOLOGICAL RHYTHM RESEARCH, vol.44, no.5, pp.807-814, 2013 (SCI-Expanded)
Chronic pruritus is a serious medical and psychiatric disorder that can have a huge impact on a patient's quality of life. Hence, we aimed to examine whether the chronotype characteristics impact on the severity of pruritus throughout the day. In our study we included 83 idiopathic chronic pruritus patients who did not have any underlying dermatological, systemic, or metabolic diseases. We examined the change in the severity of itching symptoms throughout 24 h at four time points. The latent growth modeling approach was used to assess the significance of the chronotype effect on symptom severity after controlling for age, gender, and depression. The patients with morning chronotype characteristics reported more severe itching symptoms later in the day, while the patients with evening chronotype characteristics complained of more severe itching earlier in the day. These findings suggest that chronobiological factors might play a deterministic role on the symptom severity.