title: Characteristics of beat-to-beat photoplethysmography waveform indexes in subjects with metabolic syndrome.
abstract: Metabolic syndrome (MetS) increases the risk of the subsequent development of cardiovascular disease. This study aimed to determine if the harmonic indexes of finger photoplethysmography (PPG) waveforms can be used to discriminate different arterial pulse transmission conditions between MetS and healthy subjects. Three-minute PPG signals were obtained in 65 subjects, who were assigned to 3 age-matched groups (MS, with no less than three MetS factors; pre-MS, with one or two MetS factors;
  
  
  
  with no MetS factor). FDT (foot delay time) and amplitude proportions (Cn) and their standard deviations (SDn) and coefficients of variations (CVn) were calculated for harmonics 1 to 10 of the PPG waveform. FDT was smaller in MS than in CONTROL. C1 and C2 values were significantly smaller, whereas C4-C9 values were significantly or appeared to be larger in MS than in pre-MS. Most of the SDn and CVn values were largest in MS. This study is the first to demonstrate that harmonic-analysis indexes of the beat-to-beat PPG waveform can provide information about MetS-induced changes in the arterial pulse transmission and cardiovascular regulatory activities. The present findings may therefore be useful in developing a noninvasive and easy-to-perform technique that could improve the early detection of cardiovascular diseases.
authors.affiliation: Department of Family & Community Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Yaw-Wen
authors.initials: YW
authors.lastname: Chang
authors.affiliation: Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan. Electronic address: hhsiu@mail.ntust.edu.tw.
authors.forename: Hsin
authors.initials: H
authors.lastname: Hsiu
authors.affiliation: Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan.
authors.forename: Shu-Han
authors.initials: SH
authors.lastname: Yang
authors.affiliation: Department of Family & Community Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Wen-Hwei
authors.initials: WH
authors.lastname: Fang
authors.affiliation: Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan.
authors.forename: Hung-Chi
authors.initials: HC
authors.lastname: Tsai
mesh_terms: D000328:Adult; D062186:Arterial Pressure; D002318:Cardiovascular Diseases / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D016022:Case-Control Studies; D042241:Early Diagnosis; D005260:Female; D005385:Fingers / Q000098:blood supply*; D006339:Heart Rate; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000175:diagnosis; D008833:Microcirculation; D008875:Middle Aged; D017156:Photoplethysmography; D011237:Predictive Value of Tests; D011674:Pulse; D012039:Regional Blood Flow; D013997:Time Factors
keywords: Harmonic analysis; Metabolic syndrome; Photoplethysmography; Pulse; Variability