Sleep apnea and aggressiveness

Abstract

Obstructive sleep apnea (OSA) affects the sleep quality and is associated with psychosocial problems. Testosterone participates both in the pathophysiology of OSA, affecting the upper airway collapsibility, and is the leading hormone related to aggressive conduct. The relationship between decreased sleep quality and irritability or aggressiveness is a frequent anecdotal quote, but the experimental evidence validating this relation is still scarce. Thus, we hypothesized that OSA severity influences aggressiveness in men, independently of the sleepiness and testosterone levels. The present study aimed to evaluate the association of OSA with aggressivity scores on a questionnaire, controlling for sleepiness and testosterone level. A case-control study was conducted from August 2012 to February 2013 in patients who underwent full overnight polysomnography to investigate sleep disorders. Inclusion criteria were: men aged 18 to 50 years, without organic or mental disorders, social problems, and use of behavior-altering medication, alcohol or illicit drugs. All answered the Brazilian version of the Kurzfragebogen zur Erfassung von Aggressivitatsfaktoren (K-FAF) and of the Epworth Sleepiness Scale (ESS). In this analysis, seven questions scoring peaceful manners were excluded. In the morning after the polysomnography, blood was sampled for the dosage of testosterone. Cases had an apnea hypopnea index (AHI) > 15 events/hour and controls, an AHI <15/h. The 127 men included, 87 cases and 40 controls, were aged (mean ± SD) 37 ± 8.5 years. In uncontrolled analyses, cases are older than controls ( P < 0.001), had higher body mass index ( P < 0.001), had lower testosterone levels ( p = 0.001), and lower K-FAF scores ( P = 0.005) than controls. In bivariate correlation, the AHI correlates significantly with testosterone levels ( ρ = −0.40; P < 0.001) and with scores in K-FAF questionnaire ( ρ = −0.23; P = 0.008). The only significant variable to predict K-FAF scores was AHI ( β = −0.27; P = 0.022), adjusting for age, body mass index, ESS scores, and testosterone levels in the linear regression model (adjusted R2 = 0.103; p = 0.008). The results of this study demonstrate an effect of sleep apnea in reducing scores of aggressive behavior in a specific questionnaire, controlling for confounders. Casa do Psicologo, Capes, CNPq, and FIPE- HCPA.