Comparison and correlation analysis of sleep parameters between watch-type sleep monitor (Actiwatch) and polysomnography / 北京大学学报(医学版)

OBJECTIVE@#With the rapid development of sleep medicine, there are various methods for detecting sleep diseases. This study compared the correlation between the lightweight watch-type sleep monitor (Actiwatch) and the "gold standard" polysomnography (PSG) in the Chinese population, in order to provide a basis for clinical application.@*METHODS@#From August 2018 to December 2019, 121 subjects who simultaneously performed sleep breathing monitoring (PSG) and wearing a watch-type sleep monitor (Actiwatch) in the Sleep Center of Peking University People's Hospital were enrolled. All subjects received PSG and Actiwatch at the same time, and filled out the sleep diary next morning. Monitoring indicators were collected for linear correlation analysis and paired t test to compare the differences.@*RESULTS@#Under low sensitivity conditions, the correlation coefficient of total sleep time (TST) between PSG and Actiwatch was 0.53 (P < 0.05). Paired t test analysis showed that there was no significant difference between the TSTs of Actiwatch and PSG (t=-0.890, P=0.36). According to age stratification, the smaller the age, the stronger the correlation between the TSTs of Actiwatch and PSG, and the coefficient could be up to 0.92 (P < 0.05). Paired t test showed that there was no significant difference between them (t=-1.057, P=0.35). According to the stratification by diagnosis, the correlation coefficient between the TSTs of Actiwatch and PSG in normal PSG group could be as high as 0.79 (P < 0.05), the results of paired t test showed that there was no significant difference between the TSTs of Actiwatch and PSG in normal PSG group (t=-0.784, P=0.44).@*CONCLUSION@#As a wearable home recorder, when the analysis parameters of Actiwatch were set as low sensitivity, PSG and Actiwatch had the highest TST correlation. The younger the age, the stronger correlation between the TSTs of Actiwatch and PSG. The PSG and Actiwatch subjects with normal PSG presentation had a higher TST correlation.

Orthogonal factor analysis on metabolic syndrome / 中华流行病学杂志

To elucidate the principal of orthogonal factor analysis, using an example of factor analysis of metabolic syndrome. The basic structures and the fundamental concepts of orthogonal factor analysis were introduced and data involving 1877 women aged of 35-65 years, selected from a cross-sectional study, which was conducted in 1998 - 2001 in Shanghai, were included in this study. Factor analysis was carried out using principle components analysis with Varimax orthogonal rotation of the components of the metabolic syndrome. The different components of the metabolic syndrome were not linked closely with the other components and loaded on the six different factors,which mainly reflected by the variables of obesity, blood pressure, plasma glucose, plasma insulin, triglycerides and HDL-cholesterol respectively. Six major factors of the metabolic syndrome were uncorrelated with each other and explained 86% of the variance in the original data. The factor score and total factor score for the individual could be obtained according to the component score coefficient matrix. Although the components of the metabolic syndrome were related statistically, the finding of six factors suggested that the components of the metabolic syndrome did not show high degrees of intercorrelation. As a linear method of data reduction, the mode reduced a large set of measured intercorrelation variables into a smaller set of uncorrelated factors, which explained the majority of the variance in the original variables. Factor analysis was well suited for revealing underlying patterns or structure among variables showing high degrees of intercorrelation.

Serum lipid profile changes of the adults in Shanghai communities / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the adult lipid profile of Huayang community from 1998 to 2000 and Caoyang communities in 2001.</p><p><b>METHODS</b>Representative serum samples of 5628 adults (aged 20 - 95 years) were obtained in Huayang and Caoyang communities during 1998.9 and 2001.11. Standard epidemiology questionnaire, physical check-ups and serum lipids data were analyzed.</p><p><b>RESULTS</b>After standardization to Chinese census statistics of 2000, the age-and sex-standardized means of total cholesterol, HDL-C, LDL-C and triglycerides of the two communities (Huayang vs. Caoyang) were 5.01 mmol/L vs. 4.43 mmol/L, 1.28 mmol/L vs. 1.32 mmol/L, 3.37 mmol/L vs. 2.99 mmol/L, 1.97 mmol/L vs. 1.60 mmol/L respectively, and the age- and sex- standardized prevalence of dyslipidemia was 52.9% vs. 25.1%, and the prevalence for borderline dyslipidemia was 76.0% vs. 56.2%, respectively. The decreasing order of dyslipidemia prevalence of the two communities was: elevated TG, decreased HDL-C, elevated LDL-C and TC. The standardized proportions of optimal HDL-C level were only 15.7% and 16.1% in Huayang and Caoyang respectively which was much lower than these of TG, LDL and TC.</p><p><b>CONCLUSIONS</b>The standardized prevalence of adult dyslipidemia and borderline dyslipidemia in the two communities were high. Dyslipidemia of the two communities was TG and decreased.</p>