The association between pruritic dermatoses and inflammatory factors on sleep disorders: a cross-sectional study of the National Health and Nutrition Examination Survey (NHANES)

Pruritic dermatoses and sleep disorders have significant impacts on the health and quality of life of patients. Inflammatory conditions may lead to the sensation of itching. This study was to evaluate the association between pruritic dermatoses and inflammatory factors on sleep disorders. Data in the cross-sectional study were extracted from the National Health and Nutrition Examination Survey. The study population was divided into participants with and without sleep disorders. Pruritic dermatoses were assessed by the participant's self-report. Inflammatory factors included white blood cell count (WBC), lymphocyte count (LYM) and prognostic nutritional index (PNI). Logistic regression models were used with odds ratios and confidence intervals. The attributable proportion of interaction (AP) was utilized to assess the interaction between pruritic dermatoses and inflammatory factors on sleep disorders. Totally, 3,520 participants were included and 214 (6.08%) had sleep disorders. Pruritic dermatoses were associated with sleep disorders after adjusting for gender, age, race, marital status, body mass index, drinking, smoking, asthma, hay fever, allergy, depression and caffeine. LYM was associated with sleep disorders when inflammatory factors were divided by median. The interaction between participants without pruritic dermatoses and PNI < median on sleep disorders was observed compared to participants without pruritic dermatoses and PNI > median. Pruritic dermatoses were significantly associated with sleep disorders. We also found that a high level of PNI had an enhanced effect on the relationship between pruritic dermatoses and sleep disorders. Clinicians should focus on the potential sleep-related risks and changes in inflammatory factors in patients with pruritic dermatoses and intervene in time.