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Dive into the research topics where Vahakn B. Shahinian is active.

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Featured researches published by Vahakn B. Shahinian.


American Journal of Kidney Diseases | 2015

US Renal Data System 2014 Annual Data Report: Epidemiology of Kidney Disease in the United States

Rajiv Saran; Bruce M. Robinson; Kevin C. Abbott; Lawrence Y. Agodoa; Patrick Albertus; John Z. Ayanian; Rajesh Balkrishnan; Jennifer L. Bragg-Gresham; Jie Cao; Joline L.T. Chen; Elizabeth Cope; Sai Dharmarajan; Xue Dietrich; Ashley Eckard; Paul W. Eggers; Charles Gaber; Daniel L. Gillen; Debbie S. Gipson; Haoyu Gu; Susan M. Hailpern; Yoshio N. Hall; Yun Han; Kevin He; Paul L. Hebert; Margaret Helmuth; William H. Herman; Michael Heung; David Hutton; Steven J. Jacobsen; Nan Ji

Author(s): Saran, Rajiv; Li, Yi; Robinson, Bruce; Abbott, Kevin C; Agodoa, Lawrence YC; Ayanian, John; Bragg-Gresham, Jennifer; Balkrishnan, Rajesh; Chen, Joline LT; Cope, Elizabeth; Eggers, Paul W; Gillen, Daniel; Gipson, Debbie; Hailpern, Susan M; Hall, Yoshio N; He, Kevin; Herman, William; Heung, Michael; Hirth, Richard A; Hutton, David; Jacobsen, Steven J; Kalantar-Zadeh, Kamyar; Kovesdy, Csaba P; Lu, Yee; Molnar, Miklos Z; Morgenstern, Hal; Nallamothu, Brahmajee; Nguyen, Danh V; OHare, Ann M; Plattner, Brett; Pisoni, Ronald; Port, Friedrich K; Rao, Panduranga; Rhee, Connie M; Sakhuja, Ankit; Schaubel, Douglas E; Selewski, David T; Shahinian, Vahakn; Sim, John J; Song, Peter; Streja, Elani; Kurella Tamura, Manjula; Tentori, Francesca; White, Sarah; Woodside, Kenneth; Hirth, Richard A


The New England Journal of Medicine | 2010

Reimbursement Policy and Androgen-Deprivation Therapy for Prostate Cancer

Vahakn B. Shahinian; Yong Fang Kuo; Scott M. Gilbert

BACKGROUNDnThe Medicare Modernization Act led to moderate reductions in reimbursement for androgen-deprivation therapy (ADT) for prostate cancer, starting in 2004 and followed by substantial changes in 2005. We hypothesized that these reductions would lead to decreases in the use of ADT for indications that were not evidence based.nnnMETHODSnUsing the Surveillance, Epidemiology, and End Results (SEER) Medicare database, we identified 54,925 men who received a diagnosis of incident prostate cancer from 2003 through 2005. We divided these men into groups according to the strength of the indication for ADT use. The use of ADT was deemed to be inappropriate as primary therapy for men with localized cancers of a low-to-moderate grade (for whom a survival benefit of such therapy was improbable), appropriate as adjuvant therapy with radiation therapy for men with locally advanced cancers (for whom a survival benefit was established), and discretionary for men receiving either primary or adjuvant therapy for localized but high-grade tumors. The proportion of men receiving ADT was calculated according to the year of diagnosis for each group. We used modified Poisson regression models to calculate the effect of the year of diagnosis on the use of ADT.nnnRESULTSnThe rate of inappropriate use of ADT declined substantially during the study period, from 38.7% in 2003 to 30.6% in 2004 to 25.7% in 2005 (odds ratio for ADT use in 2005 vs. 2003, 0.72; 95% confidence interval [CI], 0.65 to 0.79). There was no decrease in the appropriate use of adjuvant ADT (odds ratio, 1.01; 95% CI, 0.86 to 1.19). In cases involving discretionary use, there was a significant decline in use in 2005 but not in 2004.nnnCONCLUSIONSnChanges in the Medicare reimbursement policy in 2004 and 2005 were associated with reductions in ADT use, particularly among men for whom the benefits of such therapy were unclear. (Funded by the American Cancer Society.).


JAMA Internal Medicine | 2006

Risk of the "Androgen Deprivation Syndrome" in Men Receiving Androgen Deprivation for Prostate Cancer

Vahakn B. Shahinian; Yong Fang Kuo; Jean L. Freeman; James S. Goodwin

BACKGROUNDnAndrogen deprivation therapy for prostate cancer has been associated with a spectrum of adverse effects, such as depression, memory difficulties, and fatigue, termed the androgen deprivation syndrome. Primary care physicians providing follow-up care for men with prostate cancer will be faced with managing these effects. We therefore sought to estimate the incidence of these effects and, by using a control group, ascertain whether these effects were related to androgen deprivation itself.nnnMETHODSnWe assessed the risk of physician diagnoses of depression, cognitive impairment, or constitutional symptoms in Medicare data following androgen deprivation using a sample of 50 613 men with incident prostate cancer and 50 476 men without cancer, from 1992 through 1997, in the linked Surveillance, Epidemiology, and End Results-Medicare database. Cox proportional hazards regression was used to adjust for confounding variables.nnnRESULTSnOf men surviving at least 5 years after diagnosis, 31.3% of those receiving androgen deprivation developed at least 1 depressive, cognitive, or constitutional diagnosis compared with 23.7% in those who did not (P<.001). After adjustment for variables such as comorbidity, tumor characteristics, and age, the risks associated with androgen deprivation were substantially reduced or abolished: relative risk (RR) for depression diagnosis, 1.08 (95% confidence interval [CI], 1.02-1.15); RR for cognitive impairment, 0.99 (95% CI, 0.94-1.04); and RR for constitutional symptoms, 1.17 (95% CI, 1.13-1.22).nnnCONCLUSIONnDepressive, cognitive, and constitutional disorders occur more commonly in patients receiving androgen deprivation, but this appears to be primarily because patients receiving androgen deprivation are older and have more comorbid conditions and more advanced cancers.


American Journal of Kidney Diseases | 2000

Prevalence of HIV-associated nephropathy in autopsies of HIV-infected patients

Vahakn B. Shahinian; Srinivasan Rajaraman; Michael J. Borucki; James J. Grady; W.Mike Hollander; Tejinder S. Ahuja

Previous studies have reported that approximately 10% of the patients with human immunodeficiency virus (HIV) infection develop HIV-associated nephropathy (HIVAN). However, over the last decade, morbidity and mortality as a result of HIV-1 infection has remarkably decreased with the availability of potent new antiretroviral drugs. We therefore determined the prevalence of HIVAN from autopsy data of HIV-infected patients in more recent years (1992 to 1997). Autopsy reports of 389 patients were reviewed. In reports suggestive of possible HIVAN, slides of renal tissue were retrieved and reviewed again to ensure appropriate classification. The criteria for the diagnosis of HIVAN were focal segmental glomerulosclerosis with collapse of the glomerular tuft in some glomeruli, extensive tubular ectasia, and significant tubulointerstitial disease. Of 389 autopsy reports, 54% of the patients were black, 35% were white, and 11% were Hispanic. Thirty-three percent of the patients had a history of intravenous drug abuse. The mean CD4 count of the patients was 54 +/- 91/microL (mean +/- SD). In 27 cases, typical features of HIVAN were found based on the criteria used, accounting for an overall HIVAN prevalence of 6.9% (27 of 389 autopsies). Because the overwhelming majority of these patients were black (93%), the prevalence in blacks was 12% (25 of 209 autopsies). We conclude that although mortality and morbidity from HIV infection is decreasing, HIVAN remains an important complication of HIV infection in blacks, even in recent years.


American Journal of Nephrology | 1999

Is the Prevalence of HIV-Associated Nephropathy Decreasing?

Tejinder S. Ahuja; Michael J. Borucki; Marjorie Funtanilla; Vahakn B. Shahinian; Michael Hollander; Srinivasan Rajaraman

Initial reports have suggested that approximately 10% of patients with HIV-infection develop HIV-associated nephropathy (HIVAN). It has also been predicted that by the end of the decade, HIVAN is likely to become a third leading cause of end-stage renal disease (ESRD) in African-Americans between the ages of 20–64 years. As the morbidity and mortality from HIV-infection has decreased in the last few years, it is possible that prevalence of HIVAN is also changing. We therefore screened HIV-1-infected patients followed in our hospital for HIVAN. A screening urinalysis was performed in 557 HIV-1-infected adult patients between March and May 1998. Of these, 252 were outpatients and 305 were Texas Department of Criminal Justice inmates (TDCJI). Demographic and laboratory data of these patients was obtained from the HIV patients’ database. Fifty percent of the patients were African-American, 36.6% were Caucasian and 12.7% were Hispanic. The mean age of patients was 37 ± 8 years. Seventy-nine percent of the patients were males and a history of intravenous drug abuse (IVDA) was present in 28%. Twenty-three percent of the patients were concomitantly infected with hepatitis C virus, 4.1% were positive for hepatitis B surface antigen, and rapid plasma reagin test for syphilis was positive in 9.1%. In 38 patients who had more than 100 mg/dl (2+) proteins on screening urinalysis, total urinary proteins were quantitated by collecting 24 h urine specimens. Fifteen of these patients had urinary proteins more than 1.5 g/day (12 patients >3.5 g/24 h and 3 patients >1.5 g/24 h). A renal biopsy was done in 14 of these patients and clinical diagnosis of HIVAN was made in one patient who refused biopsy. Renal biopsies revealed HIVAN [9], diabetic nephropathy [2], membranoproliferative glomerulonephritis [2], Fibrillary glomerulonephritis [1]. All 10 patients (5 TDCJI and 5 outpatients) with HIVAN were African-American. Two of these 10 patients had a history of IVDA and another two were concomitantly infected with hepatitis C virus. The plasma viral load (Pvl) and total CD4 count was not different in patients with or without HIVAN [(Pvl log 10.05 ± 1.39 vs. 9.9 ± 2.18 copies/ml, p = 0.78) (CD4: 187 ± 192 vs. 288 ± 249 cells/μl, p = 1.17) mean ± SD]. We conclude that in our HIV-infected population HIVAN exclusively affected African-Americans and the prevalence in them was 3.5%.


Journal of the American Geriatrics Society | 2009

Cause of Death in Older Men After the Diagnosis of Prostate Cancer

Melanie Ketchandji; Yong Fang Kuo; Vahakn B. Shahinian; James S. Goodwin

OBJECTIVES: To compare survival and cause of death in men aged 65 and older diagnosed with prostate cancer and with survival and cause of death in a noncancer control population.


Journal of the National Cancer Institute | 2010

Risk of colorectal cancer in men on long-term androgen deprivation therapy for prostate cancer

Silke Gillessen; Arnoud J. Templeton; Giancarlo Marra; Yong Fang Kuo; Emanuele Valtorta; Vahakn B. Shahinian

BACKGROUNDnAndrogen deprivation with gonadotropin-releasing hormone (GnRH) agonists or orchiectomy is a common but controversial treatment for prostate cancer. Uncertainties remain about its use, particularly with increasing recognition of serious side effects. In animal studies, androgens protect against colonic carcinogenesis, suggesting that androgen deprivation may increase the risk of colorectal cancer.nnnMETHODSnWe identified 107u2009859 men in the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare database who were diagnosed with prostate cancer in 1993 through 2002, with follow-up available through 2004. The primary outcome was development of colorectal cancer, determined from SEER files on second primary cancers. Cox proportional hazards regression was used to assess the influence of androgen deprivation on the outcome, adjusted for patient and prostate cancer characteristics. All statistical tests were two-sided.nnnRESULTSnMen who had orchiectomies had the highest unadjusted incidence rate of colorectal cancer (6.3 per 1000 person-years; 95% confidence interval [CI] = 5.3 to 7.5), followed by men who had GnRH agonist therapy (4.4 per 1000 person-years; 95% CI = 4.0 to 4.9), and men who had no androgen deprivation (3.7 per 1000 person-years; 95% CI = 3.5 to 3.9). After adjustment for patient and prostate cancer characteristics, there was a statistically significant dose-response effect (P(trend) = .010) with an increasing risk of colorectal cancer associated with increasing duration of androgen deprivation. Compared with the absence of these treatments, there was an increased risk of colorectal cancer associated with use of GnRH agonist therapy for 25 months or longer (hazard ratio [HR] = 1.31, 95% CI = 1.12 to 1.53) or with orchiectomy (HR = 1.37, 95% CI = 1.14 to 1.66).nnnCONCLUSIONnLong-term androgen deprivation therapy for prostate cancer is associated with an increased risk of colorectal cancer.


American Journal of Kidney Diseases | 2016

Acute Kidney Injury Recovery Pattern and Subsequent Risk of CKD: An Analysis of Veterans Health Administration Data

Michael Heung; Diane E. Steffick; Brenda W. Gillespie; Tanushree Banerjee; Chi-yuan Hsu; Neil R. Powe; Meda E. Pavkov; Desmond E. Williams; Rajiv Saran; Vahakn B. Shahinian; Yi Li; Jennifer L. Bragg-Gresham; Hal Morgenstern; Diane Steffick; Anca Tilea; William H. Herman; Jerry Yee; William M. McClellan; Deb Gipson; Sai Dharmarajan; Rajesh Balkrishnan; April Wyncott; Kirsten Bibbins-Domingo; Deidra C. Crews; Vanessa Grubbs; Delphine S. Tuot; Yunno Zhu; Nilka Ríos Burrows; Mark S. Eberhardt; Paul W. Eggers

BACKGROUNDnStudies suggest an association between acute kidney injury (AKI) and long-term risk for chronic kidney disease (CKD), even following apparent renal recovery. Whether the pattern of renal recovery predicts kidney risk following AKI is unknown.nnnSTUDY DESIGNnRetrospective cohort.nnnSETTING & PARTICIPANTSnPatients in the Veterans Health Administration in 2011 hospitalized (> 24 hours) with at least 2 inpatient serum creatinine measurements, baseline estimated glomerular filtration rate > 60 mL/min/1.73 m², and no diagnosis of end-stage renal disease or non-dialysis-dependent CKD: 17,049 (16.3%) with and 87,715 without AKI.nnnPREDICTORnPattern of recovery to creatinine level within 0.3 mg/dL of baseline after AKI: within 2 days (fast), in 3 to 10 days (intermediate), and no recovery by 10 days (slow or unknown).nnnOUTCOMEnCKD stage 3 or higher, defined as 2 outpatient estimated glomerular filtration rates < 60 mL/min/1.73m² at least 90 days apart or CKD diagnosis, dialysis therapy, or transplantation.nnnMEASUREMENTSnRisk for CKD was modeled using modified Poisson regression and time to death-censored CKD was modeled using Cox proportional hazards regression, both stratified by AKI stage.nnnRESULTSnMost patients AKI episodes were stage 1 (91%) and 71% recovered within 2 days. At 1 year, 18.2% had developed CKD (AKI, 31.8%; non-AKI, 15.5%; P < 0.001). In stage 1, the adjusted relative risk ratios for CKD stage 3 or higher were 1.43 (95% CI, 1.39-1.48), 2.00 (95% CI, 1.88-2.12), and 2.65 (95% CI, 2.51-2.80) for fast, intermediate, and slow/unknown recovery. A similar pattern was observed in subgroup analyses incorporating albuminuria and sensitivity analysis of death-censored time to CKD.nnnLIMITATIONSnVariable timing of follow-up and mostly male veteran cohort may limit generalizability.nnnCONCLUSIONSnPatients who develop AKI during a hospitalization are at substantial risk for the development of CKD by 1 year following hospitalization and timing of AKI recovery is a strong predictor, even for the mildest forms of AKI.


Journal of Clinical Oncology | 2007

Characteristics of urologists predict the use of androgen deprivation therapy for prostate cancer.

Vahakn B. Shahinian; Yong Fang Kuo; Jean L. Freeman; Eduardo Orihuela; James S. Goodwin

PURPOSEnWe previously have reported wide variations among urologists in the use of androgen deprivation for prostate cancer. Using the Surveillance, Epidemiology, and End Results-Medicare linked database, we examined how individual urologist characteristics influenced the use of androgen deprivation therapy.nnnMETHODSnParticipants included 82,375 men with prostate cancer who were diagnosed from January 1, 1992, through December 31, 2002, and the 2,080 urologists who provided care to them. Multilevel analyses were used to estimate the likelihood of androgen deprivation use within 6 months of diagnosis in the overall cohort, in a subgroup in which use would be of uncertain benefit (primary therapy for localized prostate cancer), and in a subgroup in which use would be evidence-based (adjuvant therapy with radiation for locally advanced disease).nnnRESULTSnIn the overall cohort of patients, a multilevel model adjusted for patient characteristics, tumor characteristics, and urologist characteristics (eg, board certification, academic affiliation, patient panel size, years since medical school graduation) showed that the likelihood of androgen deprivation use was significantly greater for patients who saw urologists without an academic affiliation. This pattern also was noted when the analysis was limited to settings in which androgen deprivation would have been of uncertain benefit. Odds ratios for use in that context were 1.66 (95% CI, 1.27 to 2.16) for urologists with no academic affiliation and 1.45 (95% CI, 1.13 to 1.85) for urologists with minor versus major academic affiliations.nnnCONCLUSIONnUse of androgen deprivation for prostate cancer varies by the characteristics of the urologist. Patients of non-academically affiliated urologists were significantly more likely to receive primary androgen deprivation therapy for localized prostate cancer, a setting in which the benefits are uncertain.


Advances in Chronic Kidney Disease | 2010

The Role of Primary Care in the Management of the Chronic Kidney Disease Population

Vahakn B. Shahinian; Rajiv Saran

With the recognition of the high prevalence of CKD and its associated morbidity and mortality, increasing attention has focused on how to optimally provide care to this population. An immediate concern is that the sheer size of the population with early-stage CKD will overwhelm the capacity of the current nephrology workforce. Thus, the burden of care for most CKD patients will likely have to fall on primary care physicians (PCPs). This article reviews the issues surrounding the role of primary care in the management of the CKD population. Topics covered include specific roles that PCPs can play in the care of CKD patients, barriers and challenges to PCP involvement, and a discussion of strategies to improve the care provided to CKD patients by PCPs.

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Yong Fang Kuo

University of Texas Medical Branch

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James S. Goodwin

University of Texas Medical Branch

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Rajiv Saran

University of Michigan

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Cecilia Yee

Wayne State University

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Jean L. Freeman

University of Texas Medical Branch

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