ObjectiveTo evaluate physical activity (PA) and sedentary time in subjects with knee osteoarthritis (OA) measured by the Fitbit Charge 2 (Fitbit) and a wrist-worn ActiGraph GT3X+ (AGW) compared to the hip-worn ActiGraph (AGH).DesignWe recruited a cohort of subjects with knee OA from rheumatology clinics. Subjects wore the AGH for four weeks, AGW for two weeks, and Fitbit for two weeks over a four-week study period. We collected accelerometer counts (ActiGraphs) and steps (ActiGraphs, Fitbit) and calculated time spent in sedentary, light, and moderate-to-vigorous activity. We used triaxial PA intensity count cut-points from the literature for ActiGraph and a stride length-based cadence algorithm to categorize Fitbit PA. We compared Fitbit wear times calculated from a step-based algorithm and a novel algorithm that incorporates steps and heart rate (HR).ResultsWe enrolled 15 subjects (67% female, mean age 68 years). Relative to AGH, Fitbit, on average, overestimated steps by 39% and sedentary time by 37% and underestimated MVPA by 5 minutes. Relative to AGH, AGW overestimated steps 116%, underestimated sedentary time by 66%, and captured 281 additional MVPA minutes. The step-based wear time Fitbit algorithm captured 14% less wear time than the HR-based algorithm.ConclusionsFitbit overestimates steps and underestimates MVPA in knee OA subjects. Cut-offs validated for AGW should be developed to support the use of AGW for PA assessment. The HR-based Fitbit algorithm captured more wear time than the step-based algorithm. These data provide critical insight for researchers planning to use commercially-available accelerometers in pragmatic studies.

As neurodegenerative conditions are increasingly linked to mitochondrial dysfunction, methods for studying brain cell metabolism at high spatial resolution are needed to elucidate neurodegeneration mechanisms. Two-photon excited fluorescence (TPEF) imaging is a non-destructive, high-resolution technique for studying cell metabolism via endogenous fluorescence of reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD). We employed TPEF to study the metabolism of primary rat astrocyte and neuronal cultures under normal growth conditions and in response to manganese (Mn) treatment. Histograms of pixel-wise optical redox ratio, defined as FAD/(FAD + NAD(P)H), revealed three distinct redox distributions and significant differences in their relative weights between astrocytes and neurons. When treated with Mn, both cell types exhibited redox ratio shifts consistent with increased oxidative stress. However, the manner in which the redox distributions was affected was distinct for the two cell types. Furthermore, NAD(P)H fluorescence lifetime imaging revealed an increase in bound NAD(P)H fraction upon Mn treatment for neurons, consistent with enhanced apoptosis. Astrocytes showed a decrease in bound fraction, possibly due to a shift towards glycolytic metabolism in response to impaired respiration. These results exhibit TPEF’s utility for characterizing detailed metabolic changes of different brain cell types in response to neurotoxins.

ObjectiveWe conducted a meta-analysis and systematic review of published randomized controlled trials (RCTs) to evaluate the impact of financial incentives (FI) on objectively-measured physical activity (PA) and weight loss (WL) in adults with sedentary behavior or chronic health conditions.Evidence reviewWe performed a systematic search for RCTs published in English indexed in PubMed, Embase, or Web of Science through July 27, 2017. We limited our search to RCTs that involved an FI intervention with a monetary component, objectively-measured PA or WL outcomes, samples with either sedentary lifestyles or chronic health conditions, and a comparator group that did not receive performance-contingent FI. We calculated the mean difference and standardized mean difference (SMD) for each study and used a random effects model to summarize intervention efficacy. We used the Jadad scoring tool to assess the quality of the identified articles.ResultsWe abstracted data from 11 RCTs. Two of the 11 included studies focused on PA, totaling 126 intervention and 116 control subjects. Nine RCTs evaluated the effect of FI on WL, totaling 1,799 intervention and 1,483 control subjects. The combined estimate for change in daily steps was 940 (95%CI [306–1,574]) more in PA intervention groups than in control groups and 2.36 (95%CI [1.80–2.93]) more kilograms lost by WL intervention groups compared to control groups. The overall estimated SMD for both outcomes combined was 0.395 (95%CI [0.243–0.546; p<0.001]), favoring FI interventions.ConclusionFI interventions are efficacious in increasing PA and WL in adults with chronic conditions or sedentary adults. Public health programs to increase PA or prevent chronic disease should consider incorporating FI to improve outcomes.

Background and Objectives: We assessed frailty, measured by a comprehensive geriatric assessment-based frailty index (FI-CGA), and its association with postoperative outcomes among older thoracic surgical patients.Methods: Patients aged ≥65 years evaluated in the geriatric-thoracic clinic between June 2016 through May 2020 who underwent lung surgery were included. Frailty was defined as FI-CGA > 0.2, and "occult frailty", a level not often recognized by surgical teams, as 0.2 < FI-CGA < 0.4. A qualitative analysis of geriatric interventions was performed.Results: Seventy-three patients were included, of which 45 (62%) were nonfrail and 28 (38%) were frail. "Occult frailty" was present in 23/28 (82%). Sixty-one (84%) had lung malignancy. Geriatric interventions included delirium management, geriatricspecific pain and bowel regimens, and frailty optimization. More sublobar resections versus lobectomies (61% vs. 25%) were performed among frail patients. Frailty was not significantly associated with overall complications (odds ratio [OR]: 2.4; 95% confidence interval [CI]: 0.88-6.44; p = 0.087), major complications (OR: 2.33; 95% CI: 0.48-12.69; p = 0.293), discharge disposition (OR: 2.8; 95% CI: 0.71-11.95; p = 0.141), or longer hospital stay (1.3 more days; p = 0.18). Conclusion:Frailty and "occult frailty" are prevalent in patients undergoing lung surgery. However, with integrated geriatric management, these patients can safely undergo surgery.

Although growing evidence suggests that bariatric surgery is associated with improvements in osteoarthritis pain and functional status, the utilization of bariatric surgery among morbidly obese persons with knee osteoarthritis remained consistent from 2005 to 2014. Bariatric surgery in persons with knee osteoarthritis is generally safe, as inpatient complication and mortality rates remained low despite an increase in age and number of comorbidities.