Comorbid Diabetes Mellitus was Associated with Poorer Prognosis in Patients with COVID-19: A Retrospective Cohort Study

BackgroundThe 2019 novel coronavirus disease (COVID-19) emerged in Wuhan, Hubei province, China, and was characterized as pandemic by the World Health Organization. Diabetes mellitus is an established risk factor for poor clinical outcomes, but the association of diabetes with the prognosis of COVID-19 have not been reported yet. MethodsIn this cohort study, we retrospectively reviewed 258 consecutive hospitalized COVID-19 patients with or without diabetes at the West Court of Union Hospital of Huazhong University of Science and Technology in Wuhan, China, recruited from January 29 to February 12, 2020. The cases were confirmed by real-time PCR and the demographic, clinical, laboratory, radiological, and treatment data were collected and analyzed. Prognosis was defined as hospitalization, discharged survivor and death, which was followed up until March 12, 2020. ResultsOf the 258 hospitalized patients (63 with diabetes) with COVID-19, the median age was 64 years (range 23-91), and 138 (53.5%) were male. No significant differences in age and sex were identified between patients with and without diabetes. Common symptoms included fever (82.2%), dry cough (67.1%), polypnea (48.1%), and fatigue (38%). Patients with diabetes had significantly higher leucocyte and neutrophil counts, and higher levels of fasting blood glucose, serum creatinine, urea nitrogen and creatine kinase isoenzyme MB at admission compared with those without diabetes. COVID-19 patients with diabetes were more likely to develop severe or critical disease condition with more complications at presentation, and had higher incidence rates of antibiotic therapy, non-invasive and invasive mechanical ventilation, and death (11.1% vs. 4.1%). Cox proportional hazard model showed that diabetes (adjusted hazard ratio [aHR]=3.64; 95% confidence interval [CI]: 1.09, 12.21) and fasting blood glucose (aHR=1.19; 95% CI: 1.08, 1.31) were associated with the fatality of COVID-19, adjusting for potential confounders. ConclusionsDiabetes mellitus is associated with greater disease severity and a higher risk of mortality in patients with COVID-19. Primary and secondary prevention strategies are needed for COVID-19 patients with diabetes.

A computer-based simulator for intravascular photoacoustic images.

Intravascular photoacoustic (IVPA) is a newly developed catheter-based imaging technique for the diagnosis of arterial atherosclerosis. A framework of simulating IVPA transversal images from a cross-sectional vessel model with given optical and acoustic parameters was presented. The light illumination and transportation in multi-layered wall and atherosclerotic plaque tissues were modeled through Monte Carlo (MC) simulation. The generation and transmission of photoacoustic (PA) waves in the acoustically homogeneous medium were modeled through the PA wave equation, which is solved explicitly with a finite difference time domain (FDTD) algorithm in polar coordinates. Finally, a series of cross-sectional gray-scale images displaying the distribution of the deposited optical energy were reconstructed from the time-dependent acoustic pressure series with a time-reversal based algorithm. Experimental results demonstrate a good correlation between the simulated IVPA images and the optical absorption distribution profiles. The simulator provides a powerful tool for generating IVPA image data sets, which are used to improve the imaging catheter and to test the performance of image post-processing algorithms.

2-D image reconstruction of photoacoustic endoscopic imaging based on time-reversal.

BACKGROUNDS: Photoacoustic endoscopic (PAE) imaging is a rapidly emerging interventional imaging modality for identification and characterization of intraluminal pathological tissues. Since the scanning aperture of PAE is enclosed in the lumen, image reconstruction techniques used in photoacoustic tomography (PAT) can not be directly applied. OBJECTIVE: The purpose of this work is to design an image reconstruction method based on time-reversal (TR) for a PAE imaging catheter equipped with a single-element NFU transducer with circular scanning. METHODS: Firstly, the back-propagation of photoacoustic waves emitted from the tissue absorbers was modeled and simulated. Then, two-dimensional (2-D) grayscale images of the acoustic pressure distribution were obtained displaying the morphological structure of luminal cross-sections. A computer-simulated vessel phantom embedded with atherosclerotic plaques was used to validate and quantitatively evaluate the method. RESULT: The structural similarity (SSIM) of the images reconstructed with TR is comparable to algebraic reconstruction technique (ART), which is at least 65% higher than filtered back-projection (FBP). The time cost of TR is about 16 times that of FBP and 1/4 of ART under the same test condition. CONCLUSION: The reconstructed image quality may degrade when the photoacoustic data are incomplete due to sparse measuring locations and limited-view scanning. The spline interpolation can be used to improve the image quality and eliminate artifacts.