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DePew, Zachary S.

https://orcid.org/0000-0002-3179-2261

A5045529995 | I4210165183

Mayo Clinic

Pulmonary and Critical Care Associates

Citations 5

Measuring Gait Speed in the Out-Patient Clinic: Methodology and Feasibility

Respiratory Care | August 27, 2013 | Volume: 59 | Issue: 4 | Pages: 531-537

10.4187/respcare.02688 | PMID 23983271

Idiopathic subglottic stenosis: An evolving therapeutic algorithm

The Laryngoscope | July 1, 2013 | Volume: 124 | Issue: 2 | Pages: 498-503

10.1002/lary.24287 | PMID 23818139

Correlations Between Gait Speed, 6-Minute Walk Distance, Physical Activity, and Self-Efficacy in Patients With Severe Chronic Lung Disease

Respiratory Care | May 21, 2013 | Volume: 58 | Issue: 12 | Pages: 2113-2119

10.4187/respcare.02471 | PMID 23696689

BACKGROUND: Four-meter gait speed (4MGS) has been associated with functional capacity and overall mortality in elderly patients, and may easily be translated to daily practice. We evaluated the association of 4MGS with meaningful outcomes. METHODS: In 70 subjects we conducted the 4MGS, 6-min walk test (6MWT), objectively measured physical activity, and assessed dyspnea, quality of life, and self-efficacy for walking and routine physical activity. 4MGS was measured in 3 separate time epochs during the 6MWT, to explore 4MGS variability. RESULTS: Diagnoses included COPD (51.4%), interstitial lung disease (38.6%), and other pulmonary conditions (10%). The mean ± SD values were: 4MGS 0.85 ± 0.21 m/s, 6-min walk distance (6MWD) 305 ± 115 m, and physical activity level 1.28 ± 0.17, which is consistent with severe physical inactivity. The gait speeds within the time epochs 1–2, 3–4, and 5–6 min during the 6MWT were not significantly different: 1.01 ± 0.29 m/s, 0.98 ± 0.31 m/s, and 1.00 ± 0.31 m/s, respectively. 4MGS had a significant correlation with 6MWD ( r = 0.70, P < .001). 6MWD was the dominant variable for predicting 4MGS. Other significant predictors of 4MGS included dyspnea, self-efficacy, quality of life, and objectively measured physical activity. CONCLUSIONS: 4MGS is significantly and independently associated with 6MWD, and may serve as a reasonable simple surrogate for 6MWD in subjects with chronic lung disease. Gait speed was remarkably stable throughout the 6MWT, which supports the validity of an abbreviated walk test such as 4MGS.
Screening for severe physical inactivity in chronic obstructive pulmonary disease

Chronic Respiratory Disease | November 13, 2012 | Volume: 10 | Issue: 1 | Pages: 19-27

10.1177/1479972312464243 | PMID 23149382

Objectively measured severe physical inactivity (SPI) has been reported as the strongest independent predictor of mortality in patients with chronic obstructive pulmonary disease (COPD). Activity monitoring is not feasible in routine clinical practice; therefore, we set out to determine the utility of simple clinical measures for predicting SPI in patients with COPD. A total of 165 patients with COPD wore an activity monitor for 5 days to define the presence or absence of SPI. Logistic models were generated including the modified Medical Research Council (MMRC) dyspnea grade, spirometry and the age–dyspnea–airflow obstruction (ADO) index. Physical Activity Scale for the Elderly (PASE) and Stanford Brief Activity Scale (SBAS) were also tested for validity and reliability in a subgroup of 67 patients. The MMRC dyspnea grade, PASE score, ADO index and SBAS score were associated with SPI, but general self-efficacy and spirometry were not. An MMRC dyspnea grade ≥3 was the best independent predictor of SPI (AUC: 0.74; PPV: 0.83; NPV: 0.68) followed closely by a PASE score of <111. The combination of MMRC dyspnea grade and PASE score provided the most robust model (AUC: 0.83; Positive Predictive Value (PPV): 0.95; Negative Predictive Value (NPV): 0.63). The results were confirmed using 5000 bootstrapped models from the cohort of 165 patients. MMRC dyspnea grade ≥3 may be the best triage tool for SPI in patients with COPD. The combination of the MMRC and PASE score provided the most robust prediction. Our results may have significant practical applicability for clinicians caring for patients with COPD.
Pulmonary Mantle Cell Lymphoma: A Rare Manifestation of an Uncommon Condition

Rare Tumors | February 22, 2012 | Volume: 4 | Issue: 1 | Pages: 30-31

10.4081/rt.2012.e11 | PMID 22532909

Herein we describe the case of a 64-year old man with a history of mantle cell lymphoma found to have evidence of pulmonary parenchymal involvement by recurrence of his lymphoma. While lung involvement is not necessarily uncommon with Non-Hodgkin's lymphomas as a group, it is very rare for mantle cell lymphoma to involve the lung parenchyma. In addition, the radiographic manifestation of his pulmonary lymphoma as a discrete FDG-avid ground-glass lesion on chest imaging was also distinctly uncommon for pulmonary lymphoma which classically appears in one of three patterns: scattered ill-defined nodules, a bronchovascular/lymphangitic process, or pneumonic/alveolar consolidation effectively indistinguishable from bacterial pneumonia. Due to significant underlying lung disease our patient was not a candidate for high-dose conditioning and autologous stem cell transplantation. He was ultimately treated with rituximab and cladribine therapy and had early signs of clinical response at last correspondence.