Cluster analysis of home mechanical ventilation in copd patients: a picture of the real world and its impact on mortality

The degree of perceived taxonomic change in various lineages may be directly related to their general morphologic complexity: more complex forms appear to change more rapidly. “Rates of evolution” as customarily reported by paleontologists may therefore be a poor indication of evolutionary changes in the underlying genome. Two approaches were used to examine this problem. (1) We have estimated the degree of morphologic complexity by using the number of descriptive terms per genus, and per family, for 12 major groups of animals. Three general levels of complexity occur: (i) gastropods, bivalves and ectoprocts have relatively few terms; (ii) echinoids, foraminiferans, ostracodes, nautiloids, corals, trilobites, and brachiopods have an intermediate number of terms; (iii) mammals and ammonoids appear to have a relatively large number of terms. These 3 levels of complexity also increase in rate of taxonomic turnover; i.e., an increasing rate of evolution. (2) Using a cluster analysis based on morphologic similarity, we grouped 200 lineages of a computer-generated phylogenetic sequence according to 4 phenetic bases: 3, 5, 10 and 20 morphologic traits. Groups based on a few characters are longer lived and are commonly polyphyletic in comparison with groups based on many characters. In both the real world and the computer simulation, the bias of differential morphologic complexity may account for the observation that “only complicated animals evolve.” Most paleontologic studies of the “rate of evolution” may tell us more about morphologic complexity than about evolutionary rates of genomes.

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The characteristics of airflow obstruction and its association with treatment response in the real world in different GOLD groups of COPD patients

10.21203/rs.3.rs-145783/v1 ◽

2021 ◽

Author(s):

Qing Song ◽

Yi-Yang Zhao ◽

Yu-Qin Zeng ◽

Cong Liu ◽

Wei Cheng ◽

...

Keyword(s):

Mortality Rate ◽

Pulmonary Function ◽

Treatment Response ◽

Real World ◽

Airflow Obstruction ◽

Chronic Obstructive ◽

The Real ◽

Copd Patients ◽

Long Acting ◽

Group D

Abstract Background: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 separated spirometry from combined assessment to guide treatment. We aimed to analyze the characteristics of airflow obstruction and its association with treatment response in the real world in different GOLD groups of COPD patients. Methods: For this prospective observational study, stable COPD outpatients were enrolled and divided into Groups A, B, C and D based on GOLD 2017, and followed-up for 18 months. Data on patient demographics, pulmonary function, COPD assessment test (CAT), Clinical COPD Questionnaire (CCQ), modified Medical Research Council (mMRC), exacerbations, mortality and treatments were collected to analyze the airflow obstruction and its association with treatment response. Results: A total of 993 subjects were classified into Groups A (n = 170, 17.1%), B (n = 360, 36.3%), C (n = 122, 12.3%), and D (n = 341, 34.3%). There were significant differences in mMRC, CAT, CCQ, exacerbations and hospitalizations among different groups (P < 0.001). Groups B and D had more airflow obstruction and ventilatory disorder than Groups A and C (P < 0.05). In the same groups with different GOLD grades, the differences were mainly observed in BMI, CAT, CCQ and treatment with long-acting muscarinic antagonist (LAMA) and LAMA + long-acting β2-agonist (LABA) + inhaled corticosteroid (ICS) (P < 0.05). After 18 months of follow-up, the number of exacerbations and hospitalizations were significantly different among different groups, with Group D having the highest values. Also, there were more frequent exacerbators and a higher mortality rate in Group D. However, in the same groups with different GOLD grades, the mortality rates and number of exacerbations, hospitalizations and frequent exacerbators showed no differences. Conclusion: There were significant differences in pulmonary function in different groups. However, different GOLD grades had no impact on future exacerbations and mortality rate in the same groups.

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