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Kremers, Walter K

0000-0001-5714-3473

Mayo Clinic

Mayo Clinic, Rochester, Minnesota.

Citations 181

Rates of Brain Atrophy Across Disease Stages in Familial Frontotemporal Dementia Associated With MAPT , GRN , and C9orf72

JAMA Network Open | October 28, 2020 | Volume: 3 | Issue: 10 | Pages: e2022847

10.1001/jamanetworkopen.2020.22847 | PMID 33112398

Association of Cortical and Subcortical β-Amyloid With Standardized Measures of Depressive and Anxiety Symptoms in Adults Without Dementia

The Journal of Neuropsychiatry and Clinical Neurosciences | October 22, 2020 | Volume: 33 | Issue: 1 | Pages: 64-71

10.1176/appi.neuropsych.20050103 | PMID 33086924

Association Between Neuropsychiatric Symptoms and Functional Change in Older Non-Demented Adults: Mayo Clinic Study of Aging

Journal of Alzheimer's Disease | October 16, 2020 | Volume: 78 | Issue: 3 | Pages: 911-917

10.3233/jad-200764 | PMID 33074231

We examined the associations between baseline neuropsychiatric symptoms (NPS) and longitudinal changes in functional performance among 5,394 non-demented individuals aged ≥50 years (2,729 males; median age 74.2 years; 4,716 cognitively unimpaired, 678 mild cognitive impairment). After adjusting for age, sex, education, and medical comorbidities, NPS assessed by the Neuropsychiatric Inventory Questionnaire, clinical depression (Beck Depression Inventory score ≥13) and anxiety (Beck Anxiety Inventory score ≥10) were significantly associated with an increase in the Functional Activities Questionnaire score, indicating functional decline over time. This association may vary depending on the degree of cognitive impairment at baseline.
Larger Nephron Size and Nephrosclerosis Predict Progressive CKD and Mortality after Radical Nephrectomy for Tumor and Independent of Kidney Function

Journal of the American Society of Nephrology | September 16, 2020 | Volume: 31 | Issue: 11 | Pages: 2642-2652

10.1681/asn.2020040449 | PMID 32938650

Significance Statement Predicting outcomes on the basis of renal histology after a radical nephrectomy has been limited to studies with small sample sizes, short follow-ups, and only a descriptive characterization of histology. In this study of 936 patients followed up for a median of 6.4 years after establishing a new baseline kidney function following radical nephrectomy, the authors used morphometric methods to quantitatively characterize microstructural features on large renal wedge sections. Findings of larger nephrons and more extensive glomerulosclerosis and interstitial fibrosis predicted progressive CKD; interstitial fibrosis also predicted mortality from causes other than cancer. These findings provide insight into the important microstructural features of “generic” CKD in patients without a specific kidney disease and support the use of quantitative methods to evaluate renal histology after a radical nephrectomy to determine patients’ long-term risks. Background Nephron hypertrophy and nephrosclerosis may be important determinants of CKD and mortality. However, studies of outcomes associated with these microstructural features have been limited to small tissue specimens from patients selected for either good kidney health or known kidney disease. Methods To determine whether microstructural features are predictive of progressive CKD and mortality outcomes, we studied patients who underwent a radical nephrectomy for a tumor. Large wedge sections of renal parenchyma distal to the tumor were stained and scanned into high-resolution images; we annotated the cortex and all glomeruli to calculate glomerular volume, cortex volume per glomerulus, and percentage of globally sclerotic glomeruli. Morphometric measurements also included percentages of artery luminal stenosis and interstitial fibrosis/tubular atrophy (IF/TA) of the cortex. At follow-up visits every 6–12 months, we determined which patients experienced progressive CKD (defined as dialysis, kidney transplantation, or a 40% decline from postnephrectomy eGFR). Cox models for these outcomes were adjusted for age, sex, body mass index, hypertension, diabetes, smoking, eGFR, and proteinuria. Results Among 936 patients (mean age, 64 years; postnephrectomy baseline eGFR, 48 ml/min per 1.73 m 2 ), 117 progressive CKD events, 183 noncancer deaths, and 116 cancer deaths occurred during a median follow-up of 6.4 years. Larger glomerular volume, larger cortex per glomerulus, and higher percentage of globally sclerotic glomeruli or IF/TA predicted progressive CKD. Higher percentage IF/TA also predicted noncancer mortality. Microstructural features did not predict cancer mortality or recurrence. Conclusions After a radical nephrectomy, larger nephrons and nephrosclerosis predicted progressive CKD, and IF/TA predicted noncancer mortality. Morphometric analysis of renal parenchyma can predict noncancer clinical events in patients long after their radical nephrectomy.
Pansomatostatin Agonist Pasireotide Long-Acting Release for Patients with Autosomal Dominant Polycystic Kidney or Liver Disease with Severe Liver Involvement

Clinical Journal of the American Society of Nephrology | August 25, 2020 | Volume: 15 | Issue: 9 | Pages: 1267-1278

10.2215/cjn.13661119 | PMID 32843370

Background and objectives We assessed safety and efficacy of another somatostatin receptor analog, pasireotide long-acting release, in severe polycystic liver disease and autosomal dominant polycystic kidney disease. Pasireotide long-acting release, with its broader binding profile and higher affinity to known somatostatin receptors, has potential for greater efficacy. Design, setting, participants, & measurements Individuals with severe polycystic liver disease were assigned in a 2:1 ratio in a 1-year, double-blind, randomized trial to receive pasireotide long-acting release or placebo. Primary outcome was change in total liver volume; secondary outcomes were change in total kidney volume, eGFR, and quality of life. Results Of 48 subjects randomized, 41 completed total liver volume measurements ( n =29 pasireotide long-acting release and n =12 placebo). From baseline, there were −99±189 ml/m absolute and −3%±7% change in annualized change in height-adjusted total liver volume (from 2582±1381 to 2479±1317 ml/m) in the pasireotide long-acting release group compared with 136±117 ml/m absolute and 6%±7% increase (from 2387±759 to 2533±770 ml/m) in placebo ( P <0.001 for both). Total kidney volumes decreased by −12±34 ml/m and −1%±4% in pasireotide long-acting release compared with 21±21 ml/m and 4%±5% increase in the placebo group ( P =0.05 for both). Changes in eGFR were similar between groups. Among the n =48 randomized, adverse events included hyperglycemia (26 of 33 [79%] in pasireotide long-acting release versus four of 15 [27%] in the placebo group; P <0.001), and among the 47 without diabetes at baseline, 19 of 32 (59%) in the pasireotide long-acting release group versus one of 15 (7%) in the placebo group developed diabetes ( P =0.001). Conclusions Another somatostatin analog, pasireotide long-acting release, slowed progressive increase in both total liver volume/total kidney volume growth rates without affecting GFR decline. Participants experienced higher frequency of adverse events (hyperglycemia and diabetes). Clinical Trial registry name and registration number Pasireotide LAR in Severe Polycystic Liver Disease, NCT01670110 Podcast This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_08_28_CJN13661119.mp3
Quality of life and caregiver burden in familial frontotemporal lobar degeneration: Analyses of symptomatic and asymptomatic individuals within the LEFFTDS cohort

Alzheimer's & Dementia | July 13, 2020 | Volume: 16 | Issue: 8 | Pages: 1115-1124

10.1002/alz.12095 | PMID 32656921

AbstractObjectiveThe Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects evaluates familial frontotemporal lobar degeneration (FTLD) kindreds with MAPT, GRN, or C9orf72 mutations. Objectives were to examine whether health‐related quality of life (HRQoL) correlates with clinical symptoms and caregiver burden, and whether self‐rated and informant‐rated HRQoL would correlate with each other.MethodsIndividuals were classified using the Clinical Dementia Rating (CDR®) Scale plus National Alzheimer's Coordinating Center (NACC) FTLD. HRQoL was measured with DEMQOL and DEMQOL‐proxy; caregiver burden with the Zarit Burden Interview (ZBI). For analysis, Pearson correlations and weighted kappa statistics were calculated.ResultsThe cohort of 312 individuals included symptomatic and asymptomatic individuals. CDR® plus NACC FTLD was negatively correlated with DEMQOL (r = −0.20, P = .001), as were ZBI and DEMQOL (r = −0.22, P = .0009). There was fair agreement between subject and informant DEMQOL (κ = 0.36, P <.0001).ConclusionLower HRQoL was associated with higher cognitive/behavior impairment and higher caregiver burden. These findings demonstrate the negative impact of FTLD on individuals and caregivers.
CSF biomarkers in Olmsted County

Neurology | June 27, 2020 | Volume: 95 | Issue: 3 | Pages: No page available

10.1212/wnl.0000000000009874 | PMID 32591471

Diagnostic and Prognostic Accuracy of the Cogstate Brief Battery and Auditory Verbal Learning Test in Preclinical Alzheimer’s Disease and Incident Mild Cognitive Impairment: Implications for Defining Subtle Objective Cognitive Impairment

Journal of Alzheimer's Disease | June 9, 2020 | Volume: 76 | Issue: 1 | Pages: 261-274

10.3233/jad-200087 | PMID 32538841

Cortical atrophy patterns of incident MCI subtypes in the Mayo Clinic Study of Aging

Alzheimer's & Dementia | May 17, 2020 | Volume: 16 | Issue: 7 | Pages: 1013-1022

10.1002/alz.12108 | PMID 32418367

AbstractIntroductionWe examined differences in cortical thickness in empirically derived mild cognitive impairment (MCI) subtypes in the Mayo Clinic Study of Aging.MethodsWe compared cortical thickness of four incident MCI subtypes (n = 192) to 1257 cognitive unimpaired individuals.ResultsThe subtle cognitive impairment cluster had atrophy in the entorhinal and parahippocampal cortex. The amnestic, dysnomic, and dysexecutive clusters also demonstrated entorhinal cortex atrophy as well as thinning in temporal, parietal, and frontal isocortex in somewhat different patterns.DiscussionWe found patterns of atrophy in each of the incident MCI clusters that corresponded to their patterns of cognitive impairment. The identification of MCI subtypes based on cognitive and structural features may allow for more efficient trial and study designs. Given individuals in the subtle cognitive impairment cluster have less structural changes and cognitive decline and may represent the earliest group, this could be a unique group to target with early interventions.
Competing Risk Analysis in Renal Allograft Survival: A New Perspective to an Old Problem

Transplantation | April 25, 2020 | Volume: 105 | Issue: 3 | Pages: 668-676

10.1097/tp.0000000000003285 | PMID 32332421

Background. Graft survival after kidney transplant (KTX) is often estimated by the Kaplan-Meier (KM) method censoring for competing endpoints, primarily death. This method overestimates the incidence of graft loss. Methods. In 3157 adult KTX recipients followed for a mean of 79.2 months, we compared kidney and patient survival probabilities by KM versus competing risk analysis (CRA). These methods are extended to comparing different regression methods. Results. Compared with CRA, the probabilities of death and graft loss (censored for the other outcome) were substantially higher by KM. These differences increased with increasing follow-up time. Importantly, differences in graft losses were magnified in subgroups with greater probabilities of death. Among recipients with diabetes, the probabilities of graft loss at 20 years were 57% by KM and 32% by CRA, while for non-diabetes mellitus corresponding values were 44% and 35%. Similar results are noted when comparing older versus younger recipients. Finally, we find that the Fine-Gray method assumptions are violated when using age and gender as covariates and that the alternative method of Aalen-Johansen may be more appropriate. Conclusions. CRA provides more accurate estimates of long-term graft survival and death, particularly in subgroups of recipients with higher rates of the competing event. Overestimation of risk by KM leads to both quantitative and qualitative misinterpretations of long-term KTX outcomes. When using regression analyses, care should be taken to check assumptions to guide the choice of appropriate method.