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101.
Cathleen S. Colón-Emeric Carl F. Pieper Courtney H. Van Houtven Janet M. Grubber Kenneth W. Lyles Joanne Lafleur Robert A. Adler 《Mayo Clinic proceedings. Mayo Clinic》2018,93(12):1749-1759
Objective
To determine the association between dual-energy x-ray absorptiometry (DXA) testing for osteoporosis and subsequent fractures in US male veterans without a previous fracture.Patients and Methods
This is a propensity score–matched observational study using Centers for Medicare and Medicaid Services and Veterans Affairs (VA) data from January 1, 2000, through December 31, 2010, with a mean follow-up time of 4.7 years (range, 0-10 years). Men receiving VA primary care aged 65 to 99 years without a previous fracture (N=2,539,812) were included. Men undergoing DXA testing were propensity score matched with untested controls in a 1:3 ratio, indicating the probability of DXA testing within the next year. Time to first clinical fracture was the primary outcome. Comorbidities, demographic characteristics, medications, DXA results, and osteoporosis treatment were defined using administrative data and natural language processing. A landmark analysis contingent on surviving to 12 months after screening was completed, accounting for competing risk of mortality.Results
During follow-up of 153,311 men tested by DXA and 390,158 controls, 56,083 (10.3%) had sustained a fracture and 111,774 (20.6%) died. Overall, DXA testing was not associated with a decrease in fractures; conclusions are limited by unmeasured confounders and low medication initiation and adherence in those meeting treatment thresholds (12% of follow-up time). In contrast, DXA testing in prespecified subgroups was associated with a lower risk of fracture in comparison to the overall population who underwent DXA testing: androgen deprivation therapy (hazard ratio [HR], 0.77; 95% CI, 0.66-0.89), glucocorticoids (HR, 0.77; 95% CI, 0.72-0.84), age 80 years and older (HR, 0.85; 0.81-0.90), 1 or more VA guideline risk factors (HR, 0.91; 95% CI, 0.87-0.95), and high Fracture Risk Assessment Tool using body mass index score (HR, 0.90; 95% CI, 0.86-0.95).Conclusion
Current VA DXA testing practices are ineffective overall; interventions to improve treatment adherence are needed. Targeted DXA testing in higher-risk men was associated with a lower fracture risk. 相似文献102.
103.
Novak Alison R. Shakowski Courtney Trujillo Toby C. Wright Garth C. Mueller Scott W. Kiser Tyree H. 《Journal of thrombosis and thrombolysis》2022,54(2):276-286
Journal of Thrombosis and Thrombolysis - Despite evolving evidence, the use of direct oral anticoagulants (DOACs) in patients with extremes of body weight remains controversial. This study aimed to... 相似文献
104.
Maliha?Khan Tariq?Muzzafar Hagop?Kantarjian Ifra?Badar Nicholas?Short Xuemei?Wang Kamal?Chamoun Preetesh?Jain Courtney?DiNardo Naveen?Pemmaraju Prithviraj?Bose Gautam?Borthakur Jorge?Cortes Srdan?Verstovsek Guillermo?Garcia-Manero Zeev?EstrovEmail author 《Annals of hematology》2018,97(7):1183-1191
The impact of bone marrow fibrosis grade on the prognosis of patients with chronic myelomonocytic leukemia (CMML) remains controversial. Therefore, we examined the records of 82 patients diagnosed with CMML at our institution and summarized baseline characteristics and molecular profiles by subgroups of absent or mild (grades 0/1) and moderate (grade 2) fibrosis. Cox proportional hazards models were constructed to assess the prognostic significance of fibrosis grade. Grade 2 fibrosis was identified in 63 patients (76.8%), grade 1 in 16 patients (19.5%), and grade 0 in 3 patients (3.7%). Grade 2 fibrosis was associated with reduced hemoglobin levels (median 9.75 vs 11.0 g/dL in grade 0/1; p?=?0.04) and increased percentages of ringed sideroblasts (7.5 vs 0%; p?=?0.008). In multivariable analysis, grade 2 fibrosis was an independent predictor of poor overall survival (OS; 95% CI 1.32–6.35; HR 2.90; p?=?0.008), but not event-free survival (EFS; 95% CI 0.62–2.67; HR 1.28; p?=?0.50). Absolute neutrophil count (ANC) was found to impact OS (95% CI 1.01–1.09; HR 1.05; p?=?0.009), while both ANC (95% CI 1.00–1.07; HR 1.04; p?=?0.04) and peripheral blood blast percentage (95% CI 1.02–1.32; HR 1.16; p?=?0.02) impacted EFS. These results implicate fibrosis grade is an important indicator of prognosis, with high-grade fibrosis predicting inferior survival. Given the prevalence of marrow fibrosis in CMML, fibrosis grading should be incorporated into prognostic assessment and therapeutic decision-making. 相似文献
105.
Effect of the alpha-adrenergic blocker, doxazosin, on endothelial function and insulin action 总被引:2,自引:0,他引:2
Courtney CH McCance DR Atkinson AB Bassett J Ennis CN Sheridan B Bell PM 《Metabolism: clinical and experimental》2003,52(9):1147-1152
Essential hypertension is associated with impairment of both endothelial function and insulin action, and this has provided rationale for the use of antihypertensive agents that are at least neutral, if not beneficial, in these areas. This study examines the effect of the alpha-adrenergic blocker, doxazosin, on endothelial function and insulin action. Sixteen patients with essential hypertension were recruited with 13 (3 men/10 women; median age, 55 years; range, 38 to 65 years) completing the study. A double-blind, placebo-controlled crossover study design was used. After a 6-week placebo run-in, there were two 12-week treatment periods of either placebo or doxazosin, separated by a 6-week wash out period. Subjects were studied at the end of each treatment period with endothelial function assessed by forearm plethysmography and insulin action by the hyperinsulinemic clamp technique. Blood pressure was significantly lowered by doxazosin (doxazosin 144 +/-3/86 +/- 2 mm Hg; placebo 159 +/- 3/96 +/- 1 mm Hg, P <.005 for both systolic and diastolic pressure; mean +/- SEM). Baseline forearm blood flow (FBF) was unchanged (doxazosin 4.9 +/- 0.9; placebo 4.0 +/- 0.7 mL x 100 mL(-1) x min(-1), P >.05), however, FBF responses (area under dose response curve, percentage change in infused:control arm ratio) to acetylcholine (endothelium-dependent vasodilation) were improved by doxazosin (doxazosin 58.6 +/- 11.7 standard units [SU]; placebo 22.1 +/- 7.0 SU, P =.03) with responses to sodium nitroprusside (endothelium-independent vasodilation) unchanged (doxazosin 40.3 +/- 5.5 SU; placebo 46.3 +/- 8.1 SU, P >.05). Exogenous glucose infusion rates to maintain euglycemia during hyperinsulinemia were not significantly different (doxazosin 30.4 +/- 0.9; placebo 32.3 +/- 1.0 micromol x kg(-1) min(-1), P >.05). Suppression of postabsorptive endogenous glucose production by insulin was also unchanged by treatment (doxazosin 65.6% +/- 7.5% suppression; placebo 68.3% +/- 11.2% suppression, P >.05). Doxazosin has a neutral effect on both peripheral and hepatic insulin action, but improves endothelium-dependent vasodilation. These results indicate that doxazosin can be used safely in patients with insulin resistance, while its positive effect on endothelial function may lessen the subsequent incidence of atherosclerosis. 相似文献
106.
Laboratory and clinical experience in 55 patients with macroprolactinemia identified by a simple polyethylene glycol precipitation method 总被引:6,自引:0,他引:6
Leslie H Courtney CH Bell PM Hadden DR McCance DR Ellis PK Sheridan B Atkinson AB 《The Journal of clinical endocrinology and metabolism》2001,86(6):2743-2746
PRL exists in different forms in human serum. The predominant form is little PRL (molecular mass 23 kDa) with smaller amounts of big PRL (molecular mass 50--60 kDa) and at times big big or macroprolactin (molecular mass 150--170 kDa). The frequency and clinical consequences of macroprolactinemia have not been clearly established, mainly because of difficulty in identifying these patients biochemically. This previously required the use of gel filtration chromatography, which could not be used routinely. Recently, a screening test using polyethylene glycol (PEG) has been used to identify macroprolactin in serum. Consequently, this study was designed to examine the use of PEG precipitation in the identification of patients with a predominance of macroprolactin and to establish the clinical characteristics of such a cohort. Over 12 months, 18,258 requests for serum PRL were received and of these 1225 patients had a serum PRL more than 700 mU/L. A total of 322 of these patients (26%) had a percentage recovery after PEG precipitation of less than 40%, thus indicating the presence of a predominance of macroprolactin. Fifty-five of these patients were referred for detailed clinical assessment. Symptoms typical of hyperprolactinemia were not common in this cohort. None had sustained amenorrhea and eight have had oligomenorrhea at age less than 40 yr. One had galactorrhea. All had pituitary imaging, and four had a microadenoma with none having a macroadenoma. PEG precipitation allows easy identification of macroprolactin in routine clinical practice. As the clinical consequences of this entity at this stage seem relatively benign, referral and intensive investigation of these patients may not be necessary. However, follow-up of a large cohort is required to ensure that the long-term outlook is likewise benign. This would have important implications for both patients and healthcare systems. 相似文献
107.
108.
109.
110.
Audrey Duarte Patricia Hearons Yashu Jiang Mary Courtney Delvin Rachel N. Newsome Paul Verhaeghen 《Psychophysiology》2013,50(5):465-476
Behavioral evidence from the young suggests spatial cues that orient attention toward task‐relevant items in visual working memory (VWM) enhance memory capacity. Whether older adults can also use retrospective cues (“retro‐cues”) to enhance VWM capacity is unknown. In the current event‐related potential (ERP) study, young and old adults performed a VWM task in which spatially informative retro‐cues were presented during maintenance. Young but not older adults' VWM capacity benefited from retro‐cueing. The contralateral delay activity (CDA) ERP index of VWM maintenance was attenuated after the retro‐cue, which effectively reduced the impact of memory load. CDA amplitudes were reduced prior to retro‐cue onset in the old only. Despite a preserved ability to delete items from VWM, older adults may be less able to use retrospective attention to enhance memory capacity when expectancy of impending spatial cues disrupts effective VWM maintenance. 相似文献