ABC | Volume 111, Nº3, September 2018

Original Article Medeiros et al Obstructive sleep apnea in chagas disease Arq Bras Cardiol. 2018; 111(3):364-372 The only predictor of left atrial dimension in the multivariate analysis was Log 10 (AHI) ( β = 3.86, 95% CI: 1.91 to 5.81; p < 0.01) in the whole population (Table 4), as well as in the subgroup with Chagas cardiomyopathy. The independent predictors of the presence of ventricular dysfunctionwere AHI (≥15 events/h) (OR=3.61, 95%C.I.:1.31 to 9.98; p=0.01), systolic blood pressure (OR=1.06, 95%C.I.: 1.02 – 1.10; p =< 0.01) and male gender (OR = 3.24, 95% C.I.: 1.31 – 8.01; p = 0.01) (Table 5). Discussion To the best of our knowledge, this is the first study that evaluated OSA in consecutive patients with CD. We found a high frequency of moderate to severe OSA in patients with CD (21%). None of the participants had a previous diagnosis of OSA, which suggests a low awareness of the disease in this population. Patients with moderate to severe OSA were more hypertensive, used more antihypertensive drugs and had increased nocturnal blood pressure. In addition, moderate Figure 3 – Frequency of Obstructive Sleep Apnea in patients with Chagas disease OSA: obstructive sleep apnea; Kruskal-Wallis test. p < 0.01 p = 0.06 p = 0.93 11 28 39 89 72 61 EF < 50% EF > 50% 100 90 80 70 60 50 40 30 20 10 0 Percentage (%) Without OSA Mild OSA Mod/Severe OSA Table 4 – Univariate and multiple linear regression predictors of left atrial dimension Univariate Multivariate Variable (β) p (β) CI p Age (Years) 0.05 0.36 24h Systolic BP (mmHg) –0.03 0.46 BMI. kg/m 2 0.32 0.01 0.16 –0.01 to 0.44 0.06 Log 10 AHI (events/hour) 3.86 < 0.001 3.86 1.91 to 5.81 < 0.01 BP: blood pressure; BMI: body mass index; AHI: Apnoea-hypopnoea; CI: Confidence interval Table 5 – Logistic regression to assess predictors of ventricular dysfunction Univariate Multivariate Variable p OR CI p Age (years) 0.49 BMI. kg/m 2 0.09 Male % 0.01 3.24 1.31 – 8.01 0.01 24h Systolic BP (mmHg) 0.01 1.06 1.02 – 1.10 < 0.01 DM 0.95 AHI (≥ 15 events per hour) 0.02 3.61 1.31 – 9.98 0.01 Desaturation index. number/hour 0.25 SaO 2 < 90%. % of night time 0.21 BMI: body mass index; BP: blood pressure; DM: Diabetes mellitus; AHI: apnoea-hypopnoea; OR: odds ratio; CI: Confidence interval. 369