Additional file 1 of Role of serum periostin in severe obstructive sleep apnea with albuminuria: an observational study
Creators: name: Sunadome, Hironobu
name: Matsumoto, Hisako
name: Tachikawa, Ryo
name: Matsumoto, Takeshi
name: Kiminobu Tanizawa
name: Oga, Toru
name: Ono, Junya
name: Ohta, Shoichiro
name: Izuhara, Kenji
name: Toyohiro Hirai
name: Chin, Kazuo
Publisher: name: figshare
Year: 2020
Subjects: subject: Biochemistry
subject: Medicine
subject: Cell Biology
subject: Molecular Biology
subject: Immunology
subject: FOS: Clinical medicine
subject: FOS: Clinical medicine
subject: Cancer
subject: Science Policy
subject: Hematology

description: Additional file 1: Supplementary methods. Definitions of the severity of obstructive sleep apnea (OSA) and of high/low for the other sleep parameters. The definitions severity of OSA and high/low sleep parameters in the current study. Cluster analysis. The detailed description of cluster analysis. Definitions of comorbidities. The detailed definition of the presence of major comorbidities in the current study. Supplementary results. Characteristics of four clusters obtained according to cluster analysis. Cluster 1 was characterized mainly by younger age, male population, dyslipidemia, and high BMI but low prevalence of severe OSA. Among the four clusters, the patients in this cluster had the lowest serum periostin levels. Cluster 2 composed mainly of subjects with mild to moderate OSA and those with abnormal glycometabolism. Clusters 3 and 4 were characterized by the accumulation of severe OSA cases. Albuminuria was present in eight subjects in cluster 4 and in no subject in cluster 3. Of the eight subjects, six were positive for microalbuminuria (four with DM) and two exhibited macroalbuminuria (one with DM). Compared with cluster 3, cluster 4 had higher mean ± SD serum periostin level (87.1 ng/mL ± 32.3 vs. 66.5 ± 21.8 ng/mL, p = 0.05); higher number of subjects with high serum periostin levels of ≥87 ng/mL, which was the highest quintile of serum periostin (p = 0.02); and higher prevalence of asthma. Figure S1. Serum periostin levels in patients with/without comorbidities. The presence of major comorbidities was not associated with serum periostin levels. The black bars and the numbers in the figure represent the mean serum periostin level. Figure S2. Distribution of the four clusters on the axes of apnea–hypopnea index and serum periostin levels. The details of each cluster are described in Table 3 and in the supplementary results (“Characteristics of four clusters obtained according to cluster analysis”). The encircled size represents the number of subjects in each cluster. The encircled number represents the cluster number in Table 3. Figure S3. Serum periostin level in OSA. Overweight/obesity has negative impacts on the serum periostin level in OSA, as observed in the general population. However, high intermittent hypoxia contributes to high serum periostin level. Furthermore, severe OSA and comorbid albuminuria show positive interactions for serum periostin level. A high serum periostin in patients with OSA despite being overweight/obese may indicate a phenotype of OSA (i.e., severe OSA with albuminuria). Table S1. Clinical effects of CPAP in patients with moderate OSA. The serum periostin level did not decrease in subjects with moderate OSA after CPAP treatment (p = 0.75).