Common genetic variants in the CLDN2 and PRSS1-PRSS2 loci alter risk for alcohol-related and sporadic pancreatitis

Pancreatitis is a complex, progressively destructive inflammatory disorder. Alcohol was long thought to be the primary causative agent, but genetic contributions have been of interest since the discovery that rare PRSS1, CFTR, and SPINK1 variants were associated with pancreatitis risk. We now report two significant genome-wide associations identified and replicated at PRSS1-PRSS2 (1×10-12) and x-linked CLDN2 (p < 1×10-21) through a two-stage genome-wide study (Stage 1, 676 cases and 4507 controls; Stage 2, 910 cases and 4170 controls). The PRSS1 variant affects susceptibility by altering expression of the primary trypsinogen gene. The CLDN2 risk allele is associated with atypical localization of claudin-2 in pancreatic acinar cells. The homozygous (or hemizygous male) CLDN2 genotype confers the greatest risk, and its alleles interact with alcohol consumption to amplify risk. These results could partially explain the high frequency of alcohol-related pancreatitis in men – male hemizygous frequency is 0.26, female homozygote is 0.07

Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease

We identified rare coding variants associated with Alzheimer’s disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1×10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5×10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38×10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56×10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55×10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development

A novel Alzheimer disease locus located near the gene encoding tau protein

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordAPOE ε4, the most significant genetic risk factor for Alzheimer disease (AD), may mask effects of other loci. We re-analyzed genome-wide association study (GWAS) data from the International Genomics of Alzheimer's Project (IGAP) Consortium in APOE ε4+ (10 352 cases and 9207 controls) and APOE ε4- (7184 cases and 26 968 controls) subgroups as well as in the total sample testing for interaction between a single-nucleotide polymorphism (SNP) and APOE ε4 status. Suggestive associations (P<1 × 10-4) in stage 1 were evaluated in an independent sample (stage 2) containing 4203 subjects (APOE ε4+: 1250 cases and 536 controls; APOE ε4-: 718 cases and 1699 controls). Among APOE ε4- subjects, novel genome-wide significant (GWS) association was observed with 17 SNPs (all between KANSL1 and LRRC37A on chromosome 17 near MAPT) in a meta-analysis of the stage 1 and stage 2 data sets (best SNP, rs2732703, P=5·8 × 10-9). Conditional analysis revealed that rs2732703 accounted for association signals in the entire 100-kilobase region that includes MAPT. Except for previously identified AD loci showing stronger association in APOE ε4+ subjects (CR1 and CLU) or APOE ε4- subjects (MS4A6A/MS4A4A/MS4A6E), no other SNPs were significantly associated with AD in a specific APOE genotype subgroup. In addition, the finding in the stage 1 sample that AD risk is significantly influenced by the interaction of APOE with rs1595014 in TMEM106B (P=1·6 × 10-7) is noteworthy, because TMEM106B variants have previously been associated with risk of frontotemporal dementia. Expression quantitative trait locus analysis revealed that rs113986870, one of the GWS SNPs near rs2732703, is significantly associated with four KANSL1 probes that target transcription of the first translated exon and an untranslated exon in hippocampus (P≤1.3 × 10-8), frontal cortex (P≤1.3 × 10-9) and temporal cortex (P≤1.2 × 10-11). Rs113986870 is also strongly associated with a MAPT probe that targets transcription of alternatively spliced exon 3 in frontal cortex (P=9.2 × 10-6) and temporal cortex (P=2.6 × 10-6). Our APOE-stratified GWAS is the first to show GWS association for AD with SNPs in the chromosome 17q21.31 region. Replication of this finding in independent samples is needed to verify that SNPs in this region have significantly stronger effects on AD risk in persons lacking APOE ε4 compared with persons carrying this allele, and if this is found to hold, further examination of this region and studies aimed at deciphering the mechanism(s) are warranted

Polypharmacy among older adults with dementia compared with those without dementia in the United States.

Background/objectivesIn older persons with dementia (PWD), extensive medication use is often unnecessary, discordant with goals of care, and possibly harmful. The objective of this study was to determine the prevalence and medication constituents of polypharmacy among older PWD attending outpatient visits in the United States.DesignCross-sectional analysis.Setting and participantsPWD and persons without dementia (PWOD) aged ≥65 years attending outpatient visits recorded in the nationally representative National Ambulatory Medical Care Survey (NAMCS), 2014-2016.MeasurementsPWD were identified as those with a diagnosis of dementia on the NAMCS encounter form and/or those receiving an anti-dementia medication. Visits with PWD and PWOD were compared in terms of sociodemographic, practice/physician factors, comorbidities, and prescribing outcomes. Regression analyses examined the effect of dementia diagnosis on contributions by clinically relevant medication categories to polypharmacy (defined as being prescribed ≥5 prescription and/or nonprescription medications).ResultsThe unweighted sample involved 918 visits for PWD and 26,543 visits for PWOD, representing 29.0 and 780 million outpatient visits. PWD had a median age of 81 and on average had 2.8 comorbidities other than dementia; 63% were female. The median number of medications in PWD was eight compared with three in PWOD (p&nbsp;&lt; 0.001). After adjustment, PWD had significantly higher odds of being prescribed ≥5 medications (AOR 3.0; 95% CI: 2.1-4.3) or ≥10 medications (AOR 2.8; 95% CI: 2.0-4.2) compared with PWOD. The largest sources of medications among PWD were cardiovascular and central nervous system medications; usage from other categories was generally elevated in PWD compared with PWOD. PWD had higher odds of receiving at least one highly sedating or anticholinergic medication (AOR 2.5; 95% CI: 1.6-3.9).ConclusionIn a representative sample of outpatient visits, polypharmacy was extremely common among PWD, driven by a wide array of medication categories. Addressing polypharmacy in PWD will require cross-cutting and multidisciplinary approaches

One Step at a Time: Improving Gait Speed Measurement in a Geriatric Medicine Clinic

(1) Background: Mobility assessment is a key component of the assessment of an older adult as a part of the Age-Friendly Health System (AFHS) “geriatric 4Ms” framework. Several validated tools for assessing mobility and estimating fall risk in older adults are available. However, they are often under-utilized in daily practice even in specialty geriatric medicine care settings. We aimed to increase formal mobility assessment with brief gait speed measurement in a geriatric medicine outpatient clinic using phased change interventions. (2) Methods: This quality improvement (QI) initiative was conducted in a single outpatient geriatric medicine clinic. All clinic attendees who could complete a gait speed measurement were eligible for inclusion. The outcome measure was the completion of a 4 m gait speed. Several change interventions were implemented on a phased basis using the Model for Improvement methodology during the period from December 2018 to March 2020. Statistical process control charts were used to record gait speed measurements and detect non-random shifts. (3) Results: During this QI initiative, 80 patients were seen, accounting for 142 clinic visits. In response to change interventions, gait speed measurement at clinic visits increased from a median of 25% of visits to 67% by March 2020. (4) Conclusions: Adopting an AFHS care model is an urgent and challenging task to improve the quality of care for older adults. This initiative details how to effectively incorporate a brief, validated assessment of mobility using gait speed measurement into every geriatric medicine outpatient visit and progresses implementation of the AFHS “geriatric 4Ms”. Mobility assessment can aid in identifying older adults at increased fall risk