Roberts A.J.,University of Washington |
Yi-Frazier J.P.,Seattle Childrens Research Institute Seattle |
Mitrovich C.A.,Seattle Childrens Research Institute Seattle |
Pascual M.F.,Seattle Childrens Research Institute Seattle |
Taplin C.E.,University of Washington
Pediatric Diabetes | Year: 2016
Objective: Insulin adjustments have been shown to reduce glycemic excursions during and after exercise, but little is known about their use in youth with type 1 diabetes (T1D). We aimed to assess practices in youth with T1D around exercise, assess factors that influence practices, and examine associations between key behaviors and glycemic outcomes. Research design and methods: We developed the 'Type 1 Diabetes Report of Exercise Practices Survey (T1D-REPS)' and piloted this tool in 100 youth with T1D on an insulin pump. Participants completed a 3-day physical activity recall and 30 days of pump/glucose data were collected. Chart review was conducted for key clinical measures. Results: Eighty-four percent of participants modified their insulin regimen around exercise; only 40% reported adjusting prandial insulin immediately before exercise while 68% reported some modification (suspension or decrease) of basal insulin during exercise. Following exercise, only 10% reported reducing overnight basal insulin. Those who performed ≥ 5 glucose checks/day adjusted basal insulin during exercise more frequently than those with fewer daily glucose checks (33% vs. 13%, p = 0.05, chi-squared = 3.7), and were more likely to report decreasing insulin dose for the bedtime snack following exercise (50% vs. 17%, p = 0.004, chi-squared = 8.2). Conclusions: Despite several studies showing the frequency of hypoglycemia during and after exercise, many youth are not adjusting insulin for exercise. A tool designed to capture patient practices and provide clinicians with a framework for patient education may lead to improved safety around exercise in youth with T1D. © 2016 John Wiley & Sons A/S.
PubMed | Seattle University, University of Chicago and Seattle Childrens Research Institute Seattle
Type: | Journal: Frontiers in neuroscience | Year: 2016
Chronic intermittent hypoxia (CIH) is a common state experienced in several breathing disorders, including obstructive sleep apnea (OSA) and apneas of prematurity. Unraveling how CIH affects the CNS, and in turn how the CNS contributes to apneas is perhaps the most challenging task. The preBtzinger complex (preBtC) is a pre-motor respiratory network critical for inspiratory rhythm generation. Here, we test the hypothesis that CIH increases irregular output from the isolated preBtC, which can be mitigated by antioxidant treatment. Electrophysiological recordings from brainstem slices revealed that CIH enhanced burst-to-burst irregularity in period and/or amplitude. Irregularities represented a change in individual fidelity among preBtC neurons, and changed transmission from preBtC to the hypoglossal motor nucleus (XIIn), which resulted in increased transmission failure to XIIn. CIH increased the degree of lipid peroxidation in the preBtC and treatment with the antioxidant, 5,10,15,20-Tetrakis (1-methylpyridinium-4-yl)-21H,23H-porphyrin manganese(III) pentachloride (MnTMPyP), reduced CIH-mediated irregularities on the network rhythm and improved transmission of preBtC to the XIIn. These findings suggest that CIH promotes a pro-oxidant state that destabilizes rhythmogenesis originating from the preBtC and changes the local rhythm generating circuit which in turn, can lead to intermittent transmission failure to the XIIn. We propose that these CIH-mediated effects represent a part of the central mechanism that may perpetuate apneas and respiratory instability, which are hallmark traits in several dysautonomic conditions.