Association of polysomnographic parameters with clinical symptoms severity grading in Robin sequence patients: a cohort nested cross-sectional study

To evaluate the association of polysomnographic parameters with clinical symptom severity in Robin sequence (RS) patients.All patients diagnosed as presenting with RS at Hospital de Clínicas de Porto Alegre from October 2012 to June 2016 were enrolled. They were classified as isolated RS, RS-plus, and syndromic RS. Polysomnography (PSG) was performed, except for those patients in need of respiratory support. Symptom severity was evaluated as defined by the Cole et al.Ordinal OR (for the chance of increase in one grade on the clinical severity scale) and R2 (determination coefficient from ordinal logistic regression) were computed from data analysis.A total of 80 participants were enrolled in the study. Fifty-five of these were able to undergo polysomnography. Worsening of the studied PSG parameters was associated with increase in clinical severity grading, as follows: desaturation index (OR 1.27; 95% CI; 1.07-1.51; R2 = 19.8%; p = 0.006); apnea/hypopnea Index (OR 1.13; 95% CI; 1.01-1.26; R2 = 12.5%; p = 0.02); sleep mean oxygen saturation (OR 0.16; 95% CI; 0.05-0.52; R2 = 22.6%; p = 0.002); oxygen saturation nadir (OR 0.73; 95% CI; 0.56-0.96; R2 = 10.0%; p = 0.02); percentage of time with oxygen saturation <90% (OR 9.49; 95% CI; 1.63-55.31, R2 = 37.6%; p = 0.012); and percentage of time presenting with obstruction (OR 2.5; 95% CI; 1.31-4.76; R2 = 25.1%; p = 0.006).Polysomnography parameters were associated with severity of clinical manifestations in patients with RS. Oxyhemoglobin saturation-based parameters had surprisingly significant R2 values. Therefore, those parameters, which have traditionally been undervalued in other clinical settings, should also be assessed in the polysomnographic evaluation of RS patients.