The Deltatrac Metabolic Monitor (DTC), one of the most popular indirect calorimetry systems for measuring resting metabolic rate (RMR) in human subjects, is no longer being manufactured. This study compared five different gas analysis systems to the DTC. Resting metabolic rate was measured by the DTC and at least one other instrument at three study sites for a total of 38 participants. The five indirect calorimetry systems included: MedGraphics CPX Ultima, MedGem, Vmax Encore 29 System, TrueOne 2400, and Korr ReeVue. Validity was assessed using paired t-tests to compare means while reliability was assessed by using both paired t-tests and root mean square calculations with F tests for significance. Within-subject comparisons for validity of RMR revealed a significant difference between the DTC and Ultima. Bland-Altman plot analysis showed significant bias with increasing RMR values for the Korr and MedGem. Respiratory exchange ratio (RER) analysis showed a significant difference between the DTC and the Ultima and a trend for a difference with the Vmax (p = 0.09). Reliability assessment for RMR revealed that all instruments had a significantly larger coefficient of variation (CV) (ranging from 4.8% to 10.9%) for RMR compared to the 3.0 % CV for the DTC. Reliability assessment for RER data showed none of the instrument CV's were significantly larger than the DTC CV. The results were quite disappointing, with none of the instruments equaling the within person reliability of the DTC. The TrueOne and Vmax were the most valid instruments in comparison with the DTC for both RMR and RER assessment. Further testing is needed to identify an instrument with the reliability and validity of the DTC.Correspondence and request for reprints: Dr. Dale Schoeller,

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OBJECTIVE To determine whether rates of gestational diabetes among individuals at first live birth changed from 2011 to 2019 and how these rates differ by race and ethnicity in the US.DESIGN, SETTING, AND PARTICIPANTS Serial cross-sectional analysis using National Center for Health Statistics data for 12 610 235 individuals aged 15 to 44 years with singleton first live births from 2011 to 2019 in the US.EXPOSURES Gestational diabetes data stratified by the following race and ethnicity groups: Hispanic/Latina (including Central and South American, Cuban, Mexican, and Puerto Rican); non-Hispanic Asian/Pacific Islander (including Asian Indian, Chinese, Filipina, Japanese, Korean, and Vietnamese); non-Hispanic Black; and non-Hispanic White. MAIN OUTCOMES AND MEASURESThe primary outcomes were age-standardized rates of gestational diabetes (per 1000 live births) and respective mean annual percent change and rate ratios (RRs) of gestational diabetes in non-Hispanic Asian/Pacific Islander (overall and in subgroups), non-Hispanic Black, and Hispanic/Latina (overall and in subgroups) individuals relative to non-Hispanic White individuals (referent group). RESULTS Among the 12 610 235 included individuals (mean [SD] age, 26.3 [5.8] years), the overall age-standardized gestational diabetes rate significantly increased from 47.6 (95% CI, 47.1-48.0) to 63.5 (95% CI, 63.1-64.0) per 1000 live births from 2011 to 2019, a mean annual percent change of 3.7% (95% CI, 2.8%-4.6%) per year. Of the 12 610 235 participants, 21% were Hispanic/Latina (2019 gestational diabetes rate, 66.6 [95% CI, 65.6-67.7]; RR, 1.15 [95% CI, 1.13-1.18]), 8% were non-Hispanic Asian/Pacific Islander (2019 gestational diabetes rate, 102.7 [95% CI, 100.7-104.7]; RR, 1.78 [95% CI, 1.74-1.82]), 14% were non-Hispanic Black (2019 gestational diabetes rate, 55.7 [95% CI, 54.5-57.0]; RR, 0.97 [95% CI, 0.94-0.99]), and 56% were non-Hispanic White (2019 gestational diabetes rate, 57.7 [95% CI, 57.2-58.3]; referent group). Gestational diabetes rates were highest in Asian Indian participants (2019 gestational diabetes rate, 129.1 [95% CI, 100.7-104.7]; RR, 2.24 [95% CI,). Among Hispanic/Latina participants, gestational diabetes rates were highest among Puerto Rican individuals (2019 gestational diabetes rate, 75.8 [95% CI, 71.8-79.9]; RR, 1.31 [95% CI, 1.24-1.39]). Gestational diabetes rates increased among all race and ethnicity subgroups and across all age groups.CONCLUSIONS AND RELEVANCE Among individuals with a singleton first live birth in the US from 2011 to 2019, rates of gestational diabetes increased across all racial and ethnic subgroups. Differences in absolute gestational diabetes rates were observed across race and ethnicity subgroups.

The 100% oxygen (O 2 ) technique has been used to detect and quantify right-to-left shunt for more than 50 years. The goal of this study was to determine if breathing 100% O 2 affected intrapulmonary arteriovenous pathways during exercise. Seven healthy subjects (3 females) performed two exercise protocols. In Protocol I subjects performed an incremental cycle ergometer test (60 W + 30 W/2 min; breathing room air, F IO 2 = 0.209) and arteriovenous shunting was evaluated using saline contrast echocardiography at each stage. Once significant arteriovenous shunting was documented (bubble score = 2), workload was held constant for the remainder of the protocol and F IO 2 was alternated between 1.0 (hyperoxia) and 0.209 (normoxia) as follows: hyperoxia for 180 s, normoxia for 120 s, hyperoxia for 120 s, normoxia for 120 s, hyperoxia for 60 s and normoxia for 120 s. For Protocol II, subjects performed an incremental cycle ergometer test until volitional exhaustion while continuously breathing 100% O 2 . In Protocol I, shunting was seen in all subjects at 120-300 W. Breathing oxygen for 1 min reduced shunting, and breathing oxygen for 2 min eliminated shunting in all subjects. Shunting promptly resumed upon breathing room air. Similarly, in Protocol II, breathing 100% O 2 substantially decreased or eliminated exercise-induced arteriovenous shunting in all subjects at submaximal and in 4/7 subjects at maximal exercise intensities. Our results suggest that alveolar hyperoxia prevents or reduces blood flow through arteriovenous shunt pathways.

Our randomized trial of a promotora-led educational intervention demonstrated improved Pap screening rates, in addition to increased knowledge about cervical cancer and self-efficacy. The observed association between cervical cancer knowledge and Pap smear receipt underscores the importance of educating vulnerable populations about the diseases that disproportionately affect them. Future research should evaluate such programs on a larger scale, and identify novel targets for intervention.

IMPORTANCE Understanding cardiovascular outcomes of initiating second-line antidiabetic medications (ADMs) may help inform treatment decisions after metformin alone is not sufficient or not tolerated. To date, no studies have compared the cardiovascular effects of all major second-line ADMs during this early decision point in the pharmacologic management of type 2 diabetes. OBJECTIVE To examine the association of second-line ADM classes with major adverse cardiovascular events. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study among 132 737 insured adults with type 2 diabetes who started therapy with a second-line ADM after taking either metformin alone or no prior ADM. This study used 2011-2015 US nationwide administrative claims data. Data analysis was performed from January 2017 to October 2018. EXPOSURES Dipeptidyl peptidase 4 (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists, sodium-glucose cotransporter 2 (SGLT-2) inhibitors, thiazolidinediones (TZDs), basal insulin, and sulfonylureas or meglitinides (both referred to as sulfonylureas hereafter). The DPP-4 inhibitors served as the comparison group in all analyses. MAIN OUTCOMES AND MEASURES The primary outcome was time to first cardiovascular event after starting the second-line ADM. This composite outcome was based on hospitalization for the following cardiovascular conditions: congestive heart failure, stroke, ischemic heart disease, or peripheral artery disease. RESULTS Among 132 737 insured adult patients with type 2 diabetes (men, 55%; aged 45-64 years, 58%; white, 63%), there were 3480 incident cardiovascular events during 169 384 person-years of follow-up. Patients were censored after the first cardiovascular event, discontinuation of insurance coverage, transition from International Classification of Diseases, Ninth Revision (ICD-9) to end of ICD-9 coding, or 2 years of follow-up. After adjusting for patient, prescriber, and health plan characteristics, the risk of composite cardiovascular events after starting GLP-1 receptor agonists was lower than DPP-4 inhibitors (hazard ratio [HR], 0.78; 95% CI, 0.63-0.96), but this finding was not significant in all sensitivity analyses. Cardiovascular event rates after starting treatment with SGLT-2 inhibitors (HR, 0.81; 95% CI, 0.57-1.53) and TZDs (HR, 0.92; 95% CI, 0.76-1.11) were not statistically different from DPP-4 inhibitors. The comparative risk of cardiovascular events was higher after starting treatment with sulfonylureas (HR, 1.36; 95% CI, 1.23-1.49) or basal insulin (HR, 2.03; 95% CI, 1.81-2.27) than DPP-4 inhibitors.

Background Research evaluating community health worker (CHW) programs inherently involves these natural community leaders in the research process, and often represents community-based participatory research (CBPR). Interpreting the results of CHW intervention studies and replicating their findings requires knowledge of how CHWs are selected and trained. Methods A summative content analysis was performed to evaluate the description of CHW selection and training in the existing literature. First-level coding focused on contextual information about CHW programs. Second-level coding identified themes related to the selection and training of CHWs. Results There was inconsistent reporting of selection and training processes for CHWs in the existing literature. Common selection criteria included personal qualities desired of CHWs. Training processes for CHWs were more frequently reported. Wide variation in the length and content of CHW training exists in the reviewed studies. A conceptual model is presented for the role development of CHWs based on the results of this review, which is intended to guide future reporting of CHW programs in the intervention literature. Conclusions Consistent reporting of CHW selection and training will allow consumers of intervention research to better interpret study findings. A standard approach to reporting selection and training processes will also more effectively guide the design and implementation of future CHW programs. All community-based researchers must find a balance between describing the research process and reporting more traditional scientific content. The current conceptual model provides a guide for standard reporting in the CHW literature.

The signal from a spirometer is directly correlated with respiratory motion and is ideal for target respiratory motion tracking. However, its susceptibility to signal drift deters its application in radiotherapy. In this work, a few approaches are investigated to control spirometer signal drift for a Bernoulli-type spirometer. A method is presented for rapid daily calibration of the spirometer to obtain a flow sensitivity function. Daily calibration assures accurate airflow measurement and also reduces signal drift. Dynamic baseline adjustment further controls the signal drift. The accuracy of these techniques was studied and it was found that the spirometer is able to provide a long-term drift-free breathing signal. The tracking error is comprised of two components: calibration error and stochastic signal baseline variation error. The calibration error is very small ͑1% of 3 l͒ and therefore negligible. The stochastic baseline variation error can be as large as 20% of the normal breathing amplitude. In view of these uncertainties, the applications of spirometers in treatment techniques that rely on breathing monitoring are discussed. Spirometer-based monitoring is noted most suitable for deep inspiration breath-hold but less important for free breathing gating techniques.