Clinical research of fibroscan ‒ TE-CAP at noninvasive diagnosis of hepatic steatosis in children

BACKGROUND & AIMS

The authors assess the diagnostic accuracy of the Transient Elastography-Controlled Attenuation Parameter (TE-CAP) in children of Southern China.

METHODS

105 obese or overweight children and adolescents were enrolled in the diagnostic test of TE-CAP assessment of hepatic steatosis using MRI-PDFF. Hepatic steatosis grades S0-S3 were classified. Statistical correlation, agreement and consistency between methods were evaluated. The diagnostic efficiency of TE-CAP was evaluated. The authors used the cutoff value of TE-CAP to detect hepatic steatosis in another 356 children.

RESULTS

The Area Under Curve (AUC) of TE-CAP for grade ≥ S1, ≥ S2, and ≥ S3 steatosis were 0.975, 0.984, and 0.997, respectively. For detecting ≥ S1 steatosis, TE-CAP had a sensitivity of 96 % and a specificity of 97 %. For detecting ≥ S2 steatosis, TE-CAP had a sensitivity of 97 % and a specificity of 93 %. For detecting ≥ S3 steatosis, TE-CAP had a sensitivity of 1 and a specificity of 94 %. TE-CAP and MRI-PDFF had a linear correlation (r = 0. 0.87, p < 0.001). The hepatic steatosis was identified in 40.2 % (143/356) of children in which the obesity and overweight were 69.8 % (113/162) and 40.0 % (18/45).

CONCLUSION

TE-CAP showed excellent diagnostic accuracy in pediatric hepatic steatosis.

The Diagnostic Utility of Growth Ultrasound for the Indication of Maternal Overweight or Obesity

OBJECTIVE

 The objective of this study was to evaluate the diagnostic utility of serial growth ultrasounds for the indication of maternal overweight or obesity.

STUDY DESIGN

 This is a retrospective cohort study of all women with a body mass index ≥25 kg/m2 who underwent at least one growth ultrasound at ≥24 weeks gestation and delivered at a single tertiary care institution between January 2010 and December 2013. Women were excluded if they had other medical indications for growth ultrasounds. Ultrasounds were divided into three gestational age epochs: 24 to 316/7 weeks, 32 to 356/7 weeks, and ≥36 weeks. Outcomes examined included the accuracy of sonographic detection of fetal growth restriction (FGR) and fetal overgrowth compared with diagnoses of small for gestational age (SGA) and large for gestational age (LGA) based on the birth weight. The test characteristics of ultrasound and the number needed to screen (NNS) to detect growth abnormalities at the time of birth were estimated for each condition and gestational age epoch. The NNS for the detection of fluid abnormalities was also assessed.

RESULTS

 During the study period, 3,945 eligible sonograms were performed in 2,928 women. FGR was identified on ultrasound in 42 (1.4%) women, fetal overgrowth in 94 (3.2%) women, oligohydramnios in 35 (1.2%) women, and hydramnios in 41 (1.4%) women. The NNS for the diagnoses of SGA, LGA, oligohydramnios, and hydramnios at delivery was at least 137 prior to 32 weeks of gestation and decreased (i.e., at least 45 and 16, for 32 to 356/7 weeks and ≥36 weeks, respectively) with advancing gestational age epochs.

CONCLUSION

 If growth ultrasounds are to be performed for the sole indication of maternal overweight or obesity, consideration should be given to delaying initiation until at least 32 weeks of gestation given the infrequency of growth and fluid abnormalities identified earlier.

KEY POINTS

· There are limited data to support serial growth ultrasounds in overweight and obese women.. · The sensitivity of ultrasound for growth abnormalities at <32 weeks is low in women with BMI ≥25. · Consideration should be given to delaying initiation of growth ultrasounds until at least 32 weeks.

Deep learning-based BMI inference from structural brain MRI reflects brain alterations following lifestyle intervention

Obesity is associated with negative effects on the brain. We exploit Artificial Intelligence (AI) tools to explore whether differences in clinical measurements following lifestyle interventions in overweight population could be reflected in brain morphology. In the DIRECT-PLUS clinical trial, participants with criterion for metabolic syndrome underwent an 18-month lifestyle intervention. Structural brain MRIs were acquired before and after the intervention. We utilized an ensemble learning framework to predict Body-Mass Index (BMI) scores, which correspond to adiposity-related clinical measurements from brain MRIs. We revealed that patient-specific reduction in BMI predictions was associated with actual weight loss and was significantly higher in active diet groups compared to a control group. Moreover, explainable AI (XAI) maps highlighted brain regions contributing to BMI predictions that were distinct from regions associated with age prediction. Our DIRECT-PLUS analysis results imply that predicted BMI and its reduction are unique neural biomarkers for obesity-related brain modifications and weight loss.

Comparison between ultrasonography and computed tomography for measuring skeletal muscle mass in critically ill patients with different body mass index

BACKGROUND & AIM

Among critical patients, there is an early onset of changes in both the quantity and quality of muscle mass. It is essential to find tools that promptly identify this muscle mass loss. The aim of this study was to compare the ultrasonography of the quadriceps femoris to the gold standard, thigh computed tomography (CT) for assessing the musculature of critically ill patients with different body mass index who have suffered traumatic brain injury.

METHODS

This is a prospective validation study in an Intensive Care Unit (ICU) specialized in trauma care, located at a tertiary teaching hospital. Our study involved a convenience sample of patients. Sequential ultrasound and CT scans were performed at three distinct time intervals: upon admission, between 24 and 96 h' post-admission, and finally, between 96 and 168 h' post-admission. For all ultrasound measurements, we conducted simultaneous quadriceps CT measurements. The correlation between measurements obtained by ultrasound and computed tomography at three different times and in three BMI ranges was analyzed, in individuals with normal weight, overweight and obese.

RESULTS

Results: We analyzed 252 images in 49 patients in time 1, 40 patients in time 2, and 37 in time 3 to compare the thickness quadriceps muscle using US and CT. Of these, 18 patients had a BMI ≤ 24.9 kg/m2 (normal weight), 18 patients from 25 to 29.9 kg/m2 (overweight), and 8 patients had a BMI ≥ 30 kg/m2 (obese). The mean age was 37 years, the majority (94%) were male and the main comorbidities were: hypertension 12%, diabetes 4% and 14% smoking. The results revealed minor discrepancies between measurements obtained through the two methods, these changes were not influenced by the body mass index, with these variations being practically insignificant in the context of clinical application. Thus, the correlation and concordance between the values obtained found a strong positive correlation with good limits of agreement. The Spearman's correlation coefficients obtained were r = 0.89, 0.91 and 0.88, p < 0.01 at T1, T2 and T3 respectively for normal weight, r = 0.91, 0.80 and 0.81, p < 0.01 at T1, T2 and T3 respectively for overweight and r = 0.89, 0.94 and 0.84, p < 0.01 at T1, T2 and T3 respectively for obesity. In addition to a positive correlation, we observed a high agreement between the methods. The Bland & Altman analysis at time 1 showed, respectively, the bias of 1.46, 2.03 and 0.76. At time 2, the bias was 0.42, 3.11 and 2.12. At time 3, the bias was 2.26, 3.38 and 2.11 mm.

CONCLUSION

Our findings suggest that measure femoral quadriceps muscle thickness ultrasound-based exhibits a comparable performance to thigh CT. This conclusion stems from the excellent correlation and good agreement observed between ultrasound and CT, which is considered the gold standard for muscle assessment in critically ill patients.

TRIAL REGISTRATION

This clinical trial is registered at REBEC https://ensaiosclinicos.gov.br/ identifier: RBR-2bzspnz. The protocol was approved, on July 30, 2019, by the Research Ethics Committee of the Hospital das Clínicas, Faculdade de Medicina de Ribeirão Preto - Trial Registration Number: 3,475,851.

Clinical correlates of CT imaging-derived phenotypes among lean and overweight patients with hepatic steatosis

The objective of this study is to define CT imaging derived phenotypes for patients with hepatic steatosis, a common metabolic liver condition, and determine its association with patient data from a medical biobank. There is a need to further characterize hepatic steatosis in lean patients, as its epidemiology may differ from that in overweight patients. A deep learning method determined the spleen-hepatic attenuation difference (SHAD) in Hounsfield Units (HU) on abdominal CT scans as a quantitative measure of hepatic steatosis. The patient cohort was stratified by BMI with a threshold of 25 kg/m2 and hepatic steatosis with threshold SHAD ≥  - 1 HU or liver mean attenuation ≤ 40 HU. Patient characteristics, diagnoses, and laboratory results representing metabolism and liver function were investigated. A phenome-wide association study (PheWAS) was performed for the statistical interaction between SHAD and the binary characteristic LEAN. The cohort contained 8914 patients-lean patients with (N = 278, 3.1%) and without (N = 1867, 20.9%) steatosis, and overweight patients with (N = 1863, 20.9%) and without (N = 4906, 55.0%) steatosis. Among all lean patients, those with steatosis had increased rates of cardiovascular disease (41.7 vs 27.8%), hypertension (86.7 vs 49.8%), and type 2 diabetes mellitus (29.1 vs 15.7%) (all p < 0.0001). Ten phenotypes were significant in the PheWAS, including chronic kidney disease, renal failure, and cardiovascular disease. Hepatic steatosis was found to be associated with cardiovascular, kidney, and metabolic conditions, separate from overweight BMI.

Metabolic interactions between organs in overweight and obesity using total-body positron emission tomography

BACKGROUND AND OBJECTIVES

Overweight and obesity is a complex condition resulting from unbalanced energy homeostasis among various organs. However, systemic abnormalities in overweight and obese people are seldom explored in vivo by metabolic imaging techniques. The aim of this study was to determine metabolic abnormities throughout the body in overweight and obese adults using total-body positron emission tomography (PET) glucose uptake imaging.

METHODS

Thirty normal weight subjects [body mass index (BMI) < 25 kg/m2, 55.47 ± 13.94 years, 16 men and 14 women], and 26 overweight and obese subjects [BMI ≥ 25 kg/m2, 52.38 ± 9.52 years, 21 men and 5 women] received whole-body 18F-fluorodeoxyglucose PET imaging using the uEXPLORER. Whole-body standardized uptake value normalized by lean body mass (SUL) images were calculated. Metabolic networks were constructed based on the whole-body SUL images using covariance network approach. Both group-level and individual-level network differences between normal weight and overweight/obese subjects were evaluated. Correlation analysis was conducted between network properties and BMI for the overweight/obese subjects.

RESULTS

Compared with normal weight subjects, overweight/obese subjects exhibited altered network connectivity strength in four network nodes, namely the pancreas (p = 0.033), spleen (p = 0.021), visceral adipose tissue (VAT) (p = 1.12 × 10-5) and bone (p = 0.021). Network deviations of overweight/obese subjects from the normal weight were positively correlated with BMI (r = 0.718, p = 3.64 × 10-5). In addition, overweight/obese subjects experienced altered connections between organs, and some of the altered connections, including pancreas-right lung and VAT-bilateral lung connections were significantly correlated with BMI.

CONCLUSION

Overweight/obese individuals exhibit metabolic alterations in organ level, and altered metabolic interactions at the systemic level. The proposed approach using total-body PET imaging can reveal individual metabolic variability and metabolic deviations between organs, which would open up a new path for understanding metabolic alterations in overweight and obesity.

Associations between adiposity and white matter hyperintensities: Cross-sectional and longitudinal analyses of 34,653 participants

OBJECTIVES

White matter hyperintensities (WMH) increase the risk of stroke and cognitive impairment. This study aims to determine the cross-sectional and longitudinal associations between adiposity and WMH.

METHODS

Participants were enrolled from the UK Biobank cohort. Associations of concurrent, past, and changes in overall and central adiposity with WMH were investigated by linear and nonlinear regression models. The association of longitudinal adiposity and WMH volume changes was determined by a linear mixed model. Mediation analysis investigated the potential mediating effect of blood pressure.

RESULTS

In 34,653 participants with available adiposity measures and imaging data, the concurrent obese group had a 25.3% (β [95% CI] = 0.253 [0.222-0.284]) higher WMH volume than the ideal weight group. Increment in all adiposity measures was associated with a higher WMH volume. Among them, waist circumference demonstrated the strongest effect (β [95% CI] = 0.113 [0.101-0.125]). Past adiposity also demonstrated similar effects. Among the subset of 2664 participants with available WMH follow-up data, adiposity measures were predictive of WMH change. Regarding changes of adiposity, compared with ideal weight stable group, those who turned from ideal weight to overweight/obese had a 8.1% higher WMH volume (β [95% CI] = 0.081 [0.039-0.123]), while participants who turned from overweight/obese to ideal weight demonstrated no significant WMH volume change. Blood pressure partly meditates the associations between adiposity and WMH.

CONCLUSIONS

Both concurrent and past adiposity were associated with a higher WMH volume. The detrimental effects of adiposity on WMH occurred throughout midlife and in the elderly and may still exist after changes in obesity status.

Comparative study of abdominal CT enhancement in overweight and obese patients based on different scanning modes combined with different contrast medium concentrations

PURPOSE

To compare image quality, iodine intake, and radiation dose in overweight and obese patients undergoing abdominal computed tomography (CT) enhancement using different scanning modes and contrast medium.

METHODS

Ninety overweight and obese patients (25 kg/m2≤body mass index (BMI)< 30 kg/m2 and BMI≥30 kg/m2) who underwent abdominal CT-enhanced examinations were randomized into three groups (A, B, and C) of 30 each and scanned using gemstone spectral imaging (GSI) +320 mgI/ml, 100 kVp + 370 mgI/ml, and 120 kVp + 370 mgI/ml, respectively. Reconstruct monochromatic energy images of group A at 50-70 keV (5 keV interval). The iodine intake and radiation dose of each group were recorded and calculated. The CT values, contrast-to-noise ratios (CNRs), and subjective scores of each subgroup image in group A versus images in groups B and C were by using one-way analysis of variance or Kruskal-Wallis H test, and the optimal keV of group A was selected.

RESULTS

The dual-phase CT values and CNRs of each part in group A were higher than or similar to those in groups B and C at 50-60 keV, and similar to or lower than those in groups B and C at 65 keV and 70 keV. The subjective scores of the dual-phase images in group A were lower than those of groups B and C at 50 keV and 55 keV, whereas no significant difference was seen at 60-70 keV. Compared to groups B and C, the iodine intake in group A decreased by 12.5% and 13.3%, respectively. The effective doses in groups A and B were 24.7% and 25.8% lower than those in group C, respectively.

CONCLUSION

GSI +320 mgI/ml for abdominal CT-enhanced in overweight patients satisfies image quality while reducing iodine intake and radiation dose, and the optimal keV was 60 keV.

Reduced versus standard dose contrast volume for contrast-enhanced abdominal CT in overweight and obese patients using photon counting detector technology vs. second-generation dual-source energy integrating detector CT

PURPOSE

To compare image quality of contrast-enhanced abdominal-CT using 1st-generation Dual Source Photon-Counting Detector CT (DS-PCD-CT) versus 2nd-generation Dual-Source Energy Integrating-Detector CT (DS-EID-CT) in patients with BMI ≥ 25, applying two different contrast agent volumes, vendor proposed protocols and different virtual monoenergetic images (VMI).

METHOD

68 overweight (BMI ≥ 25 kgm2) patients (median age: 65 years; median BMI 33.3 kgm2) who underwent clinically indicated, portal-venous contrast-enhanced abdominal-CT on a commercially available 1st-generation DS-PCD-CT were prospectively included if they already have had a pre-exam on 2nd-generation DS-EID-CT using a standardized exam protocol. Obesity were defined by BMI-calculation (overweight: 25-29.9, obesity grade I: 30-34.9; obesity grade II: 35-39.9; obesity grade III: > 40) and by the absolute weight value. Body weight adapted contrast volume (targeted volume of 1.2 mL/kg for the 1st study and 0.8 mL/kg for the 2nd study) was applied in both groups. Dual Energy mode was used for both the DS-PCD-CT and the DS-EID-CT. Polychromatic images and VMI (40 keV and 70 keV) were reconstructed for both the DS-EID-CT and the DS-PCD-CT data (termed T3D). Two radiologists assessed subjective image quality using a 5-point Likert-scale. Each reader drew ROIs within parenchymatous organs and vascular structures to analyze image noise, contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR).

RESULTS

Median time interval between scans was 12 months (Min: 6 months; Max: 36 months). BMI classification included overweight (n = 10, 14.7 %), obesity grade I (n = 38, 55.9 %), grade II (n = 13, 19.1 %) and grade III (n = 7, 10.3 %). The SNR achieved with DS-PCD-CT at QIR level 3was 12.61 vs. 11.47 (QIR 2) vs. 10.53 (DS-EID-CT), irrespective of parenchymatous organs. For vessels, the SNR were 16.73 vs. 14.20 (QIR 2) vs. 12.07 (DS-EID-CT). Moreover, the obtained median noise at QIR level 3 was as low as that of the DS-EID-CT (8.65 vs. 8.65). Both radiologists rated the image quality higher for DS-PCD-CT data sets (p < 0.05). The highest CNR was achieved at 40 keV for both scanners. T3D demonstrated significantly higher SNR and lower noise level compared to 40 keV and 70 keV. Median CTDIvol and DLP values for DS-PCD-CT and DS-EID-CT were 10.90 mGy (IQR: 9.31 - 12.50 mGy) vs. 16.55 mGy (IQR: 15.45 - 18.17 mGy) and 589.50 mGy * cm (IQR: 498.50 - 708.25 mGy * cm) vs. 848.75 mGy * cm (IQR: 753.43 - 969.58 mGy * cm) (p < 0.001).

CONCLUSION

Image quality can be maintained while significantly reducing the contrast volume and the radiation dose (27% and 34% lower DLP and 31% lower CDTIvol) for abdominal contrast-enhanced CT using a 1st-generation DS-PCD-CT. Moreover, polychromatic reconstruction T3D on a DS-PCD-CT enables sufficient diagnostic image quality for oncological imaging.

Lifestyle-related risk factors and their cumulative associations with hippocampal and total grey matter volume across the adult lifespan: A pooled analysis in the European Lifebrain consortium

BACKGROUND

Lifestyle-related risk factors, such as obesity, physical inactivity, short sleep, smoking and alcohol use, have been associated with low hippocampal and total grey matter volumes (GMV). However, these risk factors have mostly been assessed as separate factors, leaving it unknown if variance explained by these factors is overlapping or additive. We investigated associations of five lifestyle-related factors separately and cumulatively with hippocampal and total GMV, pooled across eight European cohorts.

METHODS

We included 3838 participants aged 18-90 years from eight cohorts of the European Lifebrain consortium. Using individual person data, we performed cross-sectional meta-analyses on associations of presence of lifestyle-related risk factors separately (overweight/obesity, physical inactivity, short sleep, smoking, high alcohol use) as well as a cumulative unhealthy lifestyle score (counting the number of present lifestyle-related risk factors) with FreeSurfer-derived hippocampal volume and total GMV. Lifestyle-related risk factors were defined according to public health guidelines.

RESULTS

High alcohol use was associated with lower hippocampal volume (r = -0.10, p = 0.021), and overweight/obesity with lower total GMV (r = -0.09, p = 0.001). Other lifestyle-related risk factors were not significantly associated with hippocampal volume or GMV. The cumulative unhealthy lifestyle score was negatively associated with total GMV (r = -0.08, p = 0.001), but not hippocampal volume (r = -0.01, p = 0.625).

CONCLUSIONS

This large pooled study confirmed the negative association of some lifestyle-related risk factors with hippocampal volume and GMV, although with small effect sizes. Lifestyle factors should not be seen in isolation as there is evidence that having multiple unhealthy lifestyle factors is associated with a linear reduction in overall brain volume.

Higher body weight-dependent neural activation during reward processing

Obesity is associated with alterations in brain structure and function, particularly in areas related to reward processing. Although brain structural investigations have demonstrated a continuous association between higher body weight and reduced gray matter in well-powered samples, functional neuroimaging studies have typically only contrasted individuals from the normal weight and obese body mass index (BMI) ranges with modest sample sizes. It remains unclear, whether the commonly found hyperresponsiveness of the reward circuit can (a) be replicated in well-powered studies and (b) be found as a function of higher body weight even below the threshold of clinical obesity. 383 adults across the weight spectrum underwent functional magnetic resonance imaging during a common card-guessing paradigm simulating monetary reward. Multiple regression was used to investigate the association of BMI and neural activation in the reward circuit. In addition, a one-way ANOVA model comparing three weight groups (normal weight, overweight, obese) was calculated. Higher BMI was associated with higher reward response in the bilateral insula. This association could no longer be found when participants with obesity were excluded from the analysis. The ANOVA revealed higher activation in obese vs. lean, but no difference between lean and overweight participants. The overactivation of reward-related brain areas in obesity is a consistent finding that can be replicated in large samples. In contrast to brain structural aberrations associated with higher body weight, the neurofunctional underpinnings of reward processing in the insula appear to be more pronounced in the higher body weight range.

Patients with body mass index ≥25 kg/m2 as a target population for improvement of rate of follow-up duplex venous ultrasound examinations following initial incomplete examinations

OBJECTIVE

Obesity is highly prevalent and a major risk factor for deep vein thrombosis (DVT) and chronic venous disease. It can also technically limit duplex ultrasound evaluations for lower extremity DVT. We compared the rates and results of repeat lower extremity venous duplex ultrasound (LEVDUS) after an initial incomplete and negative (IIN) LEVDUS in overweight (body mass index [BMI] ≤25-30 kg/m2) and obese (BMI ≥30 kg/m2) patients with those of patients with a BMI <25 kg/m2 to evaluate whether increasing the rate of follow-up examinations in overweight and obese patients might facilitate improved patient care.

METHODS

We performed a retrospective review of 617 patients with an IIN LEVDUS study from December 31, 2017 to December 31, 2020. Demographic and imaging data of the patients with an IIN LEVDUS and the frequency of repeat studies performed within 2 weeks were abstracted from the electronic medical records. The patients were divided into three BMI-based groups: normal (BMI <25 kg/m2), overweight (BMI 25-30 kg/m2), and obese (BMI ≥30 kg/m2).

RESULTS

Of the 617 patients with an IIN LEVDUS, 213 (34.5%) were normal weight, 177 (29%) were overweight, and 227 (37%) were obese. The repeat LEVDUS rates were significantly different across the three weight groups (P < .001). After an IIN LEVDUS, the rate of repeat LEVDUS for the normal weight, overweight, and obese groups was 46% (98 of 213), 28% (50 of 227), and 32% (73 of 227), respectively. The overall rates of thrombosis (both DVT and superficial vein thrombosis) in the repeat LEVDUS examinations were not significantly different among the normal weight (14%), overweight (11%), and obese (18%) patients (P = .431).

CONCLUSIONS

Overweight and obese patients (BMI ≥25 kg/m2) received fewer follow-up examinations after an IIN LEVDUS. Follow-up LEVDUS examinations of overweight and obese patients after an IIN LEVDUS study have similar rates of venous thrombosis compared with normal weight patients. Targeting improving usage of follow-up LEVDUS studies for all patients, but especially for those who are overweight and obese, with an IIN LEVDUS through quality improvement efforts could help minimize missed diagnoses of venous thrombosis and improve the quality of patient care.

The Abdominal Ultrasonography Results of Cappadocia Cohort Study of Turkey Reveals High Prevalence of Fatty Liver

BACKGROUND

There is limited data about the prevalence of frequent gastrointestinal diseases in developing parts of the world based on community-based screening studies. Therefore, we aimed to present the detailed transabdominal ultrasonography results of the previously completed Turkey Cappadocia cohort study, which included a population-based evaluation of gastrointestinal symptoms and diseases in adults.

METHODS

This cross-sectional study was conducted in Cappadocia cohort. The transabdominal ultrasonography, anthropometric measurements, and disease questionnaires were applied to cohort persons.

RESULTS

Transabdominal ultrasonography was performed in 2797 subjects (62.3% were female and the mean age was 51 ± 15 years). Among them, 36% were overweight, 42% were obese, and 14% had diabetes mellitus. The most common pathological finding in transabdominal ultrasonography was hepatic steatosis (60.1%). The severity of hepatic steatosis was mild in 53.3%, moderate in 38.8%, and severe in 7.9%. Age, body mass index, liver size, portal vein, splenic vein diameter, hypertension, diabetes mellitus, and hyperlipidemia were significantly higher while physical activities were significantly lower in hepatic steatosis group. Ultrasonographic grade of hepatic steatosis was positively correlated with liver size, portal vein and splenic vein diameter, frequency of diabetes mellitus, hypertension, and coronary artery disease. Hepatic steatosis was observed in none of the underweight, 11.4% of the normal weights, 53.3% of the overweight, and 86.7% of the obese subjects. The percentage of hepatic steatosis cases with normal weight (lean nonalcoholic fatty liver disease) was 3.5%. The rate of lean nonalcoholic fatty liver disease in the entire cohort was 2.1%. Regression analysis revealed male gender (hazard ratio [HR]: 3.2), hypertension (HR: 1.5), and body mass index (body mass index: 25-30 HR: 9.3, body mass index >30 HR: 75.2) as independent risk factors for hepatic steatosis. The second most common ultrasonographic finding was gallbladder stone (7.6%). In the regression analysis, female gender (HR: 1.4), body mass index (body mass index: 25-30 HR: 2.1, body mass index >30 HR: 2.9), aging (30-39 age range HR: 1.5, >70 years HR: 5.8), and hypertension (HR: 1.4) were the most important risk factors for gallbladder stone.

CONCLUSIONS

Cappadocia cohort study in Turkey revealed a high prevalence of hepatic steatosis (60.1%) while the prevalence of gallbladder stones was 7.6% among the participants. The results of the Cappadocia cohort located in central Anatolia, where overweight and lack of physical activity are characteristic, showed that Turkey is one of the leading countries in the world for nonalcoholic fatty liver disease.

[State of the hepatobiliary system on the data of ultrasonic examination in children and adolescents with overweight and obesity]

Currently, a stable increase in the incidence of overweight and obesity is noted, this fact leads to an elevation in comorbidity with them. The relevance of the study is due to the involvement of the hepatobiliary system in the development of metabolic dysfunction and the formation of non-alcoholic fatty liver disease in the future. The aim of the research was to study the effect of overweight and obesity in children and adolescents on the state of the hepatobiliary system on the basis of ultrasound examination. Material and methods. A single-center retrospective comparative study was conducted. The main group consisted of 112 children and adolescents with Z-score body mass index (BMI) above +1SD, the comparison group consisted of 264 persons with a BMI from -2 to +1SD aged 5-17 years. An analysis of the results of anthropometric, including the assessment of BMI, ultrasound and biochemical studies was carried out. Results. The Z-score of BMI corresponding to overweight was recorded in 54 (13.8%) examined persons, and obesity - in 58 (14.8%) patients. In children of the main group, an increase in the size of the liver was recorded 3.6 fold more often, diffuse changes in the liver were revealed 32.4 fold more often, an increase in the volume of the gallbladder - 2.1 fold, signs of excessive aerocolia - 3.3 fold more often (p<0.001). In children with overweight and obesity, the level of triglycerides (p=0.003), low-density lipoprotein cholesterol (p=0.035), glucose (p=0.012), C-reactive protein (p=0.011), malon dyalldehyde (p=0.012), the activity of alaninaminotransferase (p<0.001) and alkaline phosphatase (p=0.001) were statistically significant, with a significantly lower level of high-density lipoprotein cholesterol (p<0.001). Statistically significant logistic models of the probability of an increase in the linear dimensions of the liver, diffuse changes, an increase in the volume of the gallbladder, the presence of excessive aerocolia signs from the Z-score BMI value were obtained. The Nigelkirk determination coefficient was 0.34, 0.17, 0.11 and 0.10 c.u. respectively. Conclusion. The contribution of overweight and obesity to the increase in the linear dimensions of the liver and the volume of the gallbladder, the formation of diffuse changes and excessive aerocolia according to the ultrasound examination was 10-34%.

The impact of body mass index on patient radiation dose in general radiography

The aim of the present study was to determine the influence of the body mass index (BMI) on the dose area product (DAP) and effective dose (ED) in overweight and obese patients. We also wanted to determine the typical dose values as well as suggest adjustments to clinical practice for overweight and obese patients. In this study we considered 597 patients referred for imaging of the chest in posteroanterior and lateral projection, the lumbar spine in anteroposterior (AP) and lateral projection, the pelvis, the knee in AP and lateral projection, and the shoulder in AP projection. For each examination, the image field size, tube voltage, mAs product, source-to-image receptor distance and values of DAP were collected. Based on their BMI, the patients were divided into three groups (normal weight, overweight and obese). At the end, PCXMC 2.0 software was used to calculate the ED. The study showed a statistically significant DAP and ED increase in overweight and obese patients by 28.9% up to 275.4% in the case of DAP and an increase in ED from 11.0% to 241.9% in all mentioned examinations except knee and shoulder imaging. Typical DAP values ranged from 2.2 to 54.8µGym²for normal-weight patients, from 2.2 to 87.6µGym²for overweight patients, and from 2.2 to 172.5µGym²for obese patients. Spearman's correlation coefficient revealed very weak to very strong correlations when comparing BMI and DAP, as well as when comparing BMI and ED. A strong and very strong correlation was found in the case of examinations of the torso (except for the comparison of BMI and ED in the case of lateral lumbar spine projection).

Sex-Specific Patterns of Body Mass Index Relationship with White Matter Connectivity

BACKGROUND

Obesity is an increasingly recognized modifiable risk factor for Alzheimer's disease (AD). Increased body mass index (BMI) is related to distinct changes in white matter (WM) fiber density and connectivity.

OBJECTIVE

We investigated whether sex differentially affects the relationship between BMI and WM structural connectivity.

METHODS

A cross-sectional sample of 231 cognitively normal participants were enrolled from the Knight Alzheimer Disease Research Center. Connectome analyses were done with diffusion data reconstructed using q-space diffeomorphic reconstruction to obtain the spin distribution function and tracts were selected using a deterministic fiber tracking algorithm.

RESULTS

We identified an inverse relationship between higher BMI and lower connectivity in the associational fibers of the temporal lobe in overweight and obese men. Normal to overweight women showed a significant positive association between BMI and connectivity in a wide array of WM fibers, an association that reversed in obese and morbidly obese women. Interaction analyses revealed that with increasing BMI, women showed higher WM connectivity in the bilateral frontoparietal and parahippocampal parts of the cingulum, while men showed lower connectivity in right sided corticostriatal and corticopontine tracts. Subgroup analyses demonstrated comparable results in participants with and without positron emission tomography or cerebrospinal fluid evidence of brain amyloidosis, indicating that the relationship between BMI and structural connectivity in men and women is independent of AD biomarker status.

CONCLUSION

BMI influences structural connectivity of WM differently in men and women across BMI categories and this relationship does not vary as a function of preclinical AD.

Effects of Arterial Stiffness and Carotid Intima-Media Thickness Progression on the Risk of Overweight/Obesity and Elevated Blood Pressure/Hypertension: a Cross-Lagged Cohort Study

We examined the temporal longitudinal associations of carotid-femoral pulse wave velocity (cfPWV), a measure of arterial stiffness, and carotid intima-media thickness (cIMT) with the risk of overweight/obesity and elevated blood pressure (BP)/hypertension. We studied 3862 adolescents aged 17.7 years from the Avon Longitudinal Study of Parents and Children, followed-up for 7 years. cfPWV and cIMT were measured by ultrasound. Total and trunk fat mass and lean mass were assessed by dual-energy X-ray absorptiometry. Body mass index and BP were measured. Data were analyzed using logistic regression, linear mixed-effect, and cross-lagged structural equation models, with covariate adjustments. Among 1719 male and 2143 female participants, higher cfPWV at 17.7 years was associated with the risk of elevated systolic BP/hypertension (odds ratio, 1.20 [1.02-1.41]; P=0.026), elevated diastolic BP/hypertension (1.77 [1.32-2.38]; P<0.0001), body mass index-overweight/obesity (1.19 [1.01-1.41]; P=0.041), and trunk fat mass overweight/obesity (1.24 [1.03-1.49]; P=0.023) at 24.5 years. Higher cIMT at 17.7 years had no associations with obesity and elevated BP at follow-up. cfPWV progression was directly associated with 7-year increase in systolic BP (effect estimate 16 mm Hg [9-24]; P<0.0001) and diastolic BP (28 mm Hg [23-34]; P<0.0001). cIMT progression was directly associated with the 7-year increase of all adiposity measures and diastolic BP. In the temporal analysis, baseline cfPWV was directly associated with follow-up systolic and diastolic BP, however, baseline BP was unassociated with follow-up cfPWV. cfPWV but not cIMT was bidirectionally associated with adiposity. Obesity and hypertension prevention from adolescence may require developing novel approaches to mitigate arterial stiffness.

Comparing feasibility of different tube voltages and different concentrations of contrast medium in coronary CT angiography of overweight patients

OBJECTIVES

To compare image quality, radiation dose, and iodine intake of coronary computed tomography angiography (CCTA) acquired by wide-detector using different tube voltages and different concentrations of contrast medium (CM) for overweight patients.

MATERIALS AND METHODS

A total of 150 overweight patients (body mass index≥25 kg/m2) who underwent CCTA are enrolled and divided into three groups according to scan protocols namely, group A (120 kVp, 370 mgI/ml CM); group B (100 kVp, 350 mgI/ml CM); and group C (80 kVp, 320 mgI/ml CM). The CT values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and figure-of-merit (FOM) of all images are calculated. Images are subjectively assessed using a 5-point scale. In addition, the CT dose index volume (CTDIvol) and dose length product (DLP) of each patient are recorded. The effective radiation dose (ED) is also calculated. Above data are then statistically analyzed.

RESULTS

The mean CT values, SNR, CNR, and subjective image quality of group A are significantly lower than those of groups B and C (P < 0.001), but there is no significant difference between groups B and C (P > 0.05). FOMs show a significantly increase trend from group A to C (P < 0.001). The ED values and total iodine intake in groups B and C are 30.34% and 68.53% and 10.22% and 16.85% lower than those in group A, respectively (P < 0.001).

CONCLUSION

The lower tube voltage and lower concentration of CM based on wide-detector allows for significant reduction in iodine load and radiation dose in CCTA for overweight patients comparing to routine scan protocols. It also enhances signal intensity of CCTA and maintains image quality.

Influence of maternal body mass index on interobserver variability of fetal ultrasound biometry and amniotic-fluid assessment in late pregnancy

OBJECTIVE

To determine the interobserver reproducibility of fetal ultrasound biometric and amniotic-fluid measurements in the third trimester of pregnancy, according to maternal body mass index (BMI) category.

METHODS

This was a prospective cohort study of women with a singleton gestation beyond 34 weeks, recruited into four groups according to BMI category: normal (18.0-24.9 kg/m² ), overweight (25.0-29.9 kg/m²⁾ , obese (30.0-39.9 kg/m² ) and morbidly obese (≥ 40 kg/m² ). Multiple pregnancies, women with diabetes and pregnancies with a fetal growth, structural or genetic abnormality were excluded. In each woman, fetal biometric (biparietal diameter (BPD), head circumference, abdominal circumference (AC), femur length (FL) and estimated fetal weight) and amniotic-fluid (amniotic-fluid index (AFI) and maximum vertical pocket (MVP)) measurements were obtained by two experienced sonographers or physicians, blinded to gestational age and each other's measurements. Differences in measurements between observers were expressed as gestational age-specific Z-scores. The interobserver intraclass correlation coefficient (ICC) and Cronbach's reliability coefficient (CRC) were calculated. Bland-Altman analysis was used to assess the degree of reproducibility.

RESULTS

In total, 110 women were enrolled prospectively (including 1320 measurements obtained by 17 sonographers or physicians). Twenty (18.2%) women had normal BMI, 30 (27.3%) women were overweight, 30 (27.3%) women were obese and 30 (27.3%) women were morbidly obese. Except for AFI (ICC, 0.65; CRC, 0.78) and MVP (ICC, 0.49; CRC, 0.66), all parameters had a very high level of interobserver reproducibility (ICC, 0.72-0.87; CRC, 0.84-0.93). When assessing reproducibility according to BMI category, BPD measurements had a very high level of reproducibility (ICC ≥ 0.85; CRC > 0.90) in all groups. The reproducibility of AC and FL measurements increased with increasing BMI, while the reproducibility of MVP measurements decreased. Among the biometric parameters, the difference between the BMI categories in measurement-difference Z-score was significant only for FL. Interobserver differences for biometric measurements fell within the 95% limits of agreement.

CONCLUSION

Obesity does not seem to impact negatively on the reproducibility of ultrasound measurements of fetal biometric parameters when undertaken by experienced sonographers or physicians who commonly assess overweight, obese and morbidly obese women. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Pre-gestational diabetes: Maternal body mass index and gestational weight gain are associated with augmented umbilical venous flow, fetal liver perfusion, and thus birthweight

OBJECTIVES

To assess how maternal body mass index and gestational weight gain are related to on fetal venous liver flow and birthweight in pregnancies with pre-gestational diabetes mellitus.

METHODS

In a longitudinal observational study, 49 women with pre-gestational diabetes mellitus were included for monthly assessments (gestational weeks 24-36). According to the Institute Of Medicine criteria, body mass index was categorized to underweight, normal, overweight, and obese, while gestational weight gain was classified as insufficient, appropriate or excessive. Fetal size, portal flow, umbilical venous flow and distribution to the fetal liver or ductus venosus were determined using ultrasound techniques. The impact of fetal venous liver perfusion on birthweight and how body mass index and gestational weight gain modified this effect, was compared with a reference population (n = 160).

RESULTS

The positive association between umbilical flow to liver and birthweight was more pronounced in pregnancies with pre-gestational diabetes mellitus than in the reference population. Overweight and excessive gestational weight gain were associated with higher birthweights in women with pre-gestational diabetes mellitus, but not in the reference population. Fetuses of overweight women with pre-gestational diabetes mellitus had higher umbilical (p = 0.02) and total venous liver flows (p = 0.02), and a lower portal flow fraction (p = 0.04) than in the reference population. In pre-gestational diabetes mellitus pregnancies with excessive gestational weight gain, the umbilical flow to liver was higher than in those with appropriate weight gain (p = 0.02).

CONCLUSIONS

The results support the hypothesis that umbilical flow to the fetal liver is a key determinant for fetal growth and birthweight modifiable by maternal factors. Maternal pre-gestational diabetes mellitus seems to augment this influence as shown with body mass index and gestational weight gain.

Fully automated waist circumference measurement on abdominal CT: Comparison with manual measurements and potential value for identifying overweight and obesity as an adjunct output of CT scan

Objective

Waist circumference (WC) is a widely accepted anthropometric parameter of central obesity. We investigated a fully automated body segmentation algorithm for measuring WC on abdominal computed tomography (CT) in comparison to manual WC measurements (WC-manual) and evaluated the performance of CT-measured WC for identifying overweight/obesity.

Materials and methods

This retrospective study included consecutive adults who underwent both abdominal CT scans and manual WC measurements at a health check-up between January 2013 and November 2019. Mid-waist WCs were automatically measured on noncontrast axial CT images using a deep learning-based body segmentation algorithm. The associations between CT-measured WC and WC-manual was assessed by Pearson correlation analysis and their agreement was assessed through Bland-Altman analysis. The performance of these WC measurements for identifying overweight/obesity (i.e., body mass index [BMI] ≥25 kg/m²) was evaluated using receiver operating characteristics (ROC) curve analysis.

Results

Among 763 subjects whose abdominal CT scans were analyzed using a fully automated body segmentation algorithm, CT-measured WCs were successfully obtained in 757 adults (326 women; mean age, 54.3 years; 64 women and 182 men with overweight/obesity). CT-measured WC was strongly correlated with WC-manual (r = 0.919, p < 0.001), and showed a mean difference of 6.1 cm with limits of agreement between -1.8 cm and 14.0 cm in comparison to WC-manual. For identifying overweight/obesity, CT-measured WC showed excellent performance, with areas under the ROC curve (AUCs) of 0.960 (95% CI, 0.933–0.979) in women and 0.909 (95% CI, 0.878–0.935) in men, which were comparable to WC-manual (AUCs of 0.965 [95% CI, 0.938–0.982] and 0.916 [95% CI, 0.886–0.941]; p = 0.735 and 0.437, respectively).

Conclusion

CT-measured WC using a fully automated body segmentation algorithm was closely correlated with manually-measured WC. While radiation issue may limit its general use, it can serve as an adjunctive output of abdominal CT scans to identify overweight/obesity.

Does overweight affect the sagittal dimension of the posterior airway space in a non-OSAS population? A case control study

OBJECTIVE

The null hypothesis was that, in a non-obstructive sleep apnea syndrome population, overweight do not reduce the antero-posterior dimension of the posterior airway space.

MATERIALS AND METHODS

The author retrospectively reviewed the records of subjects evaluated at the Maxillofacial Surgery Unit, Department of Neurosciences, University of Padova Medical School, Padova, Italy, from 2016 to 2018. Only patients with complete demographic, anthropological and CBCT dataset were enrolled. OSAS patient were also ruled-out. Enrolled patients were divided into overweight (28 cases) and non-overweight (32 controls) groups according to the patient's Body Mass Index. Each two-dimensional cephalometric radiography obtained from the cone-beam computer tomography dataset was evaluated in order to measure linear and angular distances between standardized cephalometric landmarks. The two-sample t-test was the statistical test applied to compare the case and control data.

RESULTS

There were no statistical differences between the two study groups for any of the evaluated variables: the null hypothesis was accepted.

CONCLUSION

This study showed that in a non-obstructive sleep-apnea population, overweight and class I obesity does not influence the airway space in the antero-posterior dimension. Further investigation should focus on categorized overweight-obese population. Accurate and reliable protocol for tridimensional airways assessment should be implemented.

Meeting ACR Dose Guidelines for CT Lung Cancer Screening in an Overweight and Obese Population

RATIONALE AND OBJECTIVES

Lung cancer screening adoption coincides with a growing obesity epidemic. Maintaining high-quality imaging at low radiation dose is challenging in obesity. We investigate the feasibility of meeting American College of Radiology (ACR) dose guidelines for lung cancer screening in a predominantly overweight and obese population.

MATERIALS AND METHODS

Radiation dose (Volumetric CT dose index [CTDIvol], dose-length product), and body mass index (BMI) were collected for baseline screening CTs December, 2012-December, 2017. Dose metrics were analyzed according to BMI classification (normal <25, overweight 25-29, obese ≥30 kg/m²), using k = 0.014 mSv/mGy*cm. Results were compared to ACR dose guidelines and mean national 2017 Lung Cancer Screening Registry dose metrics. Analysis used Kruskal-Wallis (SPSS, version 24.0.0, IBM corp, Armonk, NY).

RESULTS

Study population comprised 1478 patients (49.2% [727] women: mean BMI 28.1 ± 6.5 kg/m², 26.9% [397] normal weight, 35.9% [530] overweight, 37.2% [551] obese). ACR dose requirements were met for both genders in all BMI classifications. Dose metrics were higher in men than in women; median effective dose and CTDIvol were 1.39 (0.8-1.58) mSv and 2.78 (1.41-2.80) mGy in men versus 1.16 (0.71-1.43) mSv and 2.70 (1.4-2.78) mGy in women. There were significant differences in dose metrics between men and women in the same BMI classification and between BMI classifications (p < 0.001). Mean dose metrics in our program were considerably lower than 2017 national average- mean CTDIvol and effective dose 2.45 ± 1.14 mGy and 1.26 ± 0.59 mSv versus 3.24 mGy and 1.35 mSv, respectively for our program and nationally. Mean dose metrics were also lower in our obese patients versus obese patients nationally.

CONCLUSION

ACR dose metrics for lung cancer screening were met and can be appropriately tailored in a predominantly overweight and obese population clinical program.

Implications of Abdominal Adipose Tissue Distribution on Nonalcoholic Fatty Liver Disease and Metabolic Syndrome: A Chinese General Population Study

INTRODUCTION

Visceral adipose tissue (VAT) has been found to play a critical role in the development of metabolic syndrome and nonalcoholic fatty liver disease (NAFLD) independent of generalized obesity.

METHODS

In this secondary study of prospectively acquired data, 625 participants underwent magnetic resonance spectroscopy and chemical shift fat-water separation MRI (2-point Dixon) of the liver and whole abdomen, respectively, in a 3 Tesla magnet. Whole abdominal VAT and subcutaneous adipose tissue (SAT) were extracted from the 2-point Dixon image series using an automated method. Clinical/anthropometric/blood biochemistry parameters were measured. Using region-specific body mass index, participants were classified into 3 paired subgroups (lean, overweight, and obese) and presence of NAFLD (liver fat content ≥ 5.5%).

RESULTS

All relevant clinical/anthropometric/blood biochemistry characteristics and liver enzymes were statistically significant between groups (P < 0.001). NAFLD was found in 12.1%, 43.8%, and 68.3% and metabolic syndrome in 51.1%, 61.9%, and 65% of the lean, overweight, and obese, respectively. Odds ratio for metabolic syndrome and NAFLD was increased by 2.73 (95% confidence interval [CI] 2.18-3.40) and 2.53 (95% CI 2.04-3.12), respectively, for 1SD increase in VAT volume while prevalence of metabolic syndrome was increased by 2.26 (95% CI 1.83-2.79) for 1SD increase in liver fat content (%). VAT/SAT ratio in the lean with fatty liver showed the highest ratio (0.54) among all the subgroups, without a significant difference between the lean and obese with NAFLD (P = 0.127).

DISCUSSION

Increased VAT volume/disproportional distribution of VAT/SAT may be vital drivers to the development of metabolic syndrome and NAFLD irrespective of body mass index category.

Toward a Routine Assessment of Visceral Adipose Tissue Volume from Computed Tomographic Data

OBJECTIVE

The study's aim was to determine to what extent total visceral adipose tissue (VAT) volume (V_VAT-T ) measured from segmented VAT areas (A_VAT ) on all axial computed tomography (CT) sections (thickness of 5 mm) between the diaphragm and pelvic floor can be predicted by the A_VAT of commonly selected landmark sections in patients with overweight or obesity.

METHODS

A total of 113 patients (31 females, 82 males) with images of full abdominopelvic coverage and proper image quality were included (BMI = 25.0-64.1 kg/m² , 29.5 ± 4.9 kg/m² ). Linear regression between A_VAT and V_VAT-T (reference) was used to determine approximate equations for VAT volume for all parameters (single sex, different anatomical landmarks or lumbar intervertebral disc spaces, one or five axial sections). Agreement was evaluated by the multivariate coefficient of determination and by the SD of the percentage difference (s_d% ) between the estimated VAT volume on one or five sections and V_VAT-T .

RESULTS

The V_VAT-T was 0.9 to 8.4 (3.8 ± 2.2) L for females and 2.7 to 11.7 (5.6 ± 2.1) L for males. Best agreement was found at L2-3 (s_d%  = 14.3%-15.5%) for females and at L1-2 or L2-3 (11.7%-12.4%) for males. Agreement at the umbilicus or the femoral heads was poor (20.2%-57.9%). Segmentation of one or five sections was substantially faster (11/70 seconds) than whole-abdomen processing (15 minutes).

CONCLUSIONS

V_VAT-T can be rapidly estimated by VAT segmentation of axial CT sections at sex-specific lumbar intervertebral disc spaces.