Effects of Glucagon-like Peptide-1 Receptor Agonists on Upper Endoscopy in Diabetic and Non-Diabetic Patients.

BACKGROUND AND AIMS: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) promote weight loss by suppressing appetite, enhancing satiety, regulating glucose metabolism and delaying gastric motility. We sought to determine whether GLP-1 RA use could impact sedated medical procedures like esophagogastroduodenoscopy (EGD). METHODS: We conducted a retrospective study on 35,183 patients who underwent EGD between 2019 and 2023, 922 of which were using a GLP-1-RA. Data were collected regarding demographics, diabetes status, retained gastric contents during EGD (RGC), incidence of aborted EGD, and necessity for repeat EGD. RESULTS: GLP-1 RA use was associated with a fourfold increase in the retention of gastric contents (p<0.0001), fourfold higher rates of aborted EGD (p<0.0001), and twice the likelihood of requiring repeat EGD (p=0.0001), even after stratifying for presence of diabetes. CONCLUSIONS: GLP-1 RA use can lead to delayed gastric emptying, affecting EGD adequacy regardless of the presence of diabetes, and may warrant dose adjustment to improve safety and efficacy of these procedures.

Obesity medicine as a subspecialty and United States certification - A review.

Background: Certification of obesity medicine for physicians in the United States occurs mainly via the American Board of Obesity Medicine (ABOM). Obesity medicine is not recognized as a subspecialty by the American Board of Medical Specialties (ABMS) or the American Osteopathic Association (AOA). This review examines the value of specialization, status of current ABOM Diplomates, governing bodies involved in ABMS/AOA Board Certification, and the advantages and disadvantages of an ABMS/AOA recognized obesity medicine subspecialty. Methods: Data for this review were derived from PubMed and appliable websites. Content was driven by the expertise, insights, and perspectives of the authors. Results: The existing ABOM obesity medicine certification process has resulted in a dramatic increase in the number of Obesity Medicine Diplomates. If ABMS/AOA were to recognize obesity medicine as a subspecialty under an existing ABMS Member Board, then Obesity Medicine would achieve a status like other ABMS recognized subspecialities. However, the transition of ABOM Diplomates to ABMS recognized subspecialists may affect the kinds and the number of physicians having an acknowledged focus on obesity medicine care. Among transition issues to consider include: (1) How many ABMS Member Boards would oversee Obesity Medicine as a subspecialty and which physicians would be eligible? (2) Would current ABOM Diplomates be required to complete an Obesity Medicine Fellowship? If not, then what would be the process for a current ABOM Diplomate to transition to an ABMS-recognized Obesity Medicine subspecialist (i.e., "grandfathering criteria")? and (3) According to the ABMS, do enough Obesity Medicine Fellowship programs exist to recognize Obesity Medicine as a subspecialty? Conclusions: Decisions regarding a transition to an ABMS recognized Obesity Medicine Subspecialty versus retention of the current ABOM Diplomate Certification should consider which best facilitates medical access and care to patients with obesity, and which best helps obesity medicine clinicians be recognized for their expertise.

Qualitative inquiry with persons with obesity about weight management in primary care and referrals.

Introduction: Referrals to evidence-based weight management in the community-commercial sector are aligned with clinical recommendations but underutilized. Methods: This qualitative study explored patients' perceptions and expectations about obesity treatment in primary care and referral to community-commercial sector programs. Individual semi-structured interviews were conducted with a sample of US persons with obesity via telephone. Audiotape transcripts, interviewer notes, and independent review of data by two investigators allowed for data and investigator triangulation. Transcripts were analyzed using thematic analysis. Results: Data saturation was reached with 30 participants who had a mean age of 41.6 years (SD 9.4), 37% male, 20% Black/African American and 17% Hispanic, 57% college educated, and 50% were employed full-time. Three primary themes emerged: (1) frustration with weight management in primary care; (2) patients expect providers to be better informed of and offer treatment options; and (3) opportunities and challenges with referrals to community-commercial programs. Discussion: Patients expect that providers offer personalized treatment options and referrals to effective community-commercial programs are an acceptable option. If patient-level data are shared between clinical and community entities to facilitate referrals, then privacy and security issues need attention. Future research is needed to determine feasibility of implementing clinical to community-commercial referrals for obesity treatment in the United States.

Blockbuster Medications for Obesity: A Primer for Nephrologists.

The prevalence of obesity in the United States and across the world continues to climb, imparting increased risk of chronic disease. This impact is doubly felt in nephrology because obesity not only increases the risk of chronic kidney disease (CKD) but also exacerbates existing cardiovascular morbidity and mortality. The role of medical weight loss therapy in CKD has been debated, but increasing evidence suggests that intentional weight loss is protective against adverse kidney and cardiovascular outcomes. This may be particularly true with the advent of novel pharmacotherapies taking advantage of the incretin system, resulting in weight loss approaching that seen with surgical interventions. Moreover, these novel therapies have repeatedly demonstrated protective effects on the cardiovascular system. Here, we review the impact of obesity and weight loss on CKD, and the biological basis and clinical evidence for incretin therapy. This perspective provides recommended prescribing practices as a practical tool to engage nephrologists and patients with CKD in the treatment of obesity-related morbidity.

Prior metabolic surgery reduced COVID-19 severity: Systematic analysis from year one of the COVID-19 pandemic.

Background: Obesity is a risk factor for COVID-19 severity. Recent studies suggest that prior metabolic surgery (MS) modifies the risk of COVID-19 severity. Methods: COVID-19 outcomes were compared between patients with MS (n = 287) and a matched cohort of unoperated patients (n = 861). Multiple logistic regression was used to identify predictors of hospitalization. A systematic literature review and pooled analysis was conducted to provide overall evidence of the influence of prior metabolic surgery on COVID-19 outcomes. Results: COVID-19 patients with MS had less hospitalization (9.8% versus 14.3%, p = 0.049). Age 70+, higher BMI, and low weight regain after MS were associated with more hospitalization after COVID-19. A systematic review of 7 studies confirmed that MS reduced the risk of post-COVID-19 hospitalization (OR = 0.71, 95%CI = [0.61-0.83], p < 0.0001) and death (OR = 0.44, 95%CI = [0.30-0.65], p < 0.0001). Conclusion: MS favorably modifies the risks of severe COVID-19 infection. Older age and higher BMI are major risk factors for severity of COVID-19 infection.

Clinical significance of iron deficiency among candidates for metabolic surgery.

BACKGROUND: Iron deficiency (ID), a known complication after metabolic surgery, is common among preoperative patients in the presence of inflammation. Evidence is now accumulating that preoperative ID may adversely affect perioperative outcomes. OBJECTIVES: To investigate the relationship between preoperative iron status and the risk of postoperative severe anemia. In addition, this study investigates the relationship between preoperative iron status and length of surgical stay SETTING: A large regional tertiary health system. METHODS: Among patients who underwent metabolic surgery between 2004 and 2020, 5171 patients had a full iron nutritional assessment prior to surgery. Study patients were divided into multiple smaller groups (10 female groups and 7 male groups) on the basis of levels of serum ferritin and Transferrin Saturation (T Sat) < or ≥20%. Study patients were followed after surgery and the time to the development of severe anemia (hemoglobin < 8 gm/dL) was recorded. Hospital length of stay (LOS) was analyzed in relation to preoperative iron status. RESULTS: Lower ferritin levels were associated with older age in males (P = .0001) and younger age in females (P < .0001). For males, after adjustment for age, body mass index (BMI), and year of surgery, surgical LOS was prolonged in those with T Sat <20% (P = .0041). For females the time until the development of severe anemia was associated with baseline iron status (P < .0001). CONCLUSIONS: Male preoperative patients for metabolic surgery with T Sat <20% are at risk for increased surgical LOS. Females with low ferritin levels consistent with ID are at increased risk for the development of postoperative severe anemia.

Prospective Study of Diet Quality and the Risk of Dementia in the Oldest Old.

This study examined the associations between overall diet quality and the risk of dementia in a rural cohort among the oldest old. Included in this prospective cohort study were 2232 participants aged ≥ 80 years and dementia-free at the baseline according to the Geisinger Rural Aging Study (GRAS), a longitudinal cohort in rural Pennsylvania. In 2009, diet quality was assessed by a validated dietary screening tool (DST). Incident cases of dementia during 2009-2021 were identified using diagnosis codes. This approach was validated by a review of electronic health records. Associations between diet quality scores and the incidence of dementia were estimated using the Cox proportional hazards models, adjusted for potential confounders. Across a mean of 6.90 years of follow-up, we identified 408 incident cases of all-cause dementia. Having a higher diet quality was not significantly associated with a lower risk for incidents of all-cause dementia (adjusted HR for the highest compared with the lowest tertile: 1.01, 95% CI: 0.79, 1.29, P-trend = 0.95). Similarly, we did not observe a significant association between diet quality and altered risks of Alzheimer's disease and other forms of dementia. Overall, having a higher diet quality was not significantly associated with a lower risk of dementia among the oldest old during the full follow-up.

Multiancestry exome sequencing reveals INHBE mutations associated with favorable fat distribution and protection from diabetes.

Body fat distribution is a major, heritable risk factor for cardiometabolic disease, independent of overall adiposity. Using exome-sequencing in 618,375 individuals (including 160,058 non-Europeans) from the UK, Sweden and Mexico, we identify 16 genes associated with fat distribution at exome-wide significance. We show 6-fold larger effect for fat-distribution associated rare coding variants compared with fine-mapped common alleles, enrichment for genes expressed in adipose tissue and causal genes for partial lipodystrophies, and evidence of sex-dimorphism. We describe an association with favorable fat distribution (p = 1.8 × 10-09), favorable metabolic profile and protection from type 2 diabetes (~28% lower odds; p = 0.004) for heterozygous protein-truncating mutations in INHBE, which encodes a circulating growth factor of the activin family, highly and specifically expressed in hepatocytes. Our results suggest that inhibin ßE is a liver-expressed negative regulator of adipose storage whose blockade may be beneficial in fat distribution-associated metabolic disease.

Germline Mutations in CIDEB and Protection against Liver Disease.

BACKGROUND: Exome sequencing in hundreds of thousands of persons may enable the identification of rare protein-coding genetic variants associated with protection from human diseases like liver cirrhosis, providing a strategy for the discovery of new therapeutic targets. METHODS: We performed a multistage exome sequencing and genetic association analysis to identify genes in which rare protein-coding variants were associated with liver phenotypes. We conducted in vitro experiments to further characterize associations. RESULTS: The multistage analysis involved 542,904 persons with available data on liver aminotransferase levels, 24,944 patients with various types of liver disease, and 490,636 controls without liver disease. We found that rare coding variants in APOB, ABCB4, SLC30A10, and TM6SF2 were associated with increased aminotransferase levels and an increased risk of liver disease. We also found that variants in CIDEB, which encodes a structural protein found in hepatic lipid droplets, had a protective effect. The burden of rare predicted loss-of-function variants plus missense variants in CIDEB (combined carrier frequency, 0.7%) was associated with decreased alanine aminotransferase levels (beta per allele, -1.24 U per liter; 95% confidence interval [CI], -1.66 to -0.83; P = 4.8×10-9) and with 33% lower odds of liver disease of any cause (odds ratio per allele, 0.67; 95% CI, 0.57 to 0.79; P = 9.9×10-7). Rare coding variants in CIDEB were associated with a decreased risk of liver disease across different underlying causes and different degrees of severity, including cirrhosis of any cause (odds ratio per allele, 0.50; 95% CI, 0.36 to 0.70). Among 3599 patients who had undergone bariatric surgery, rare coding variants in CIDEB were associated with a decreased nonalcoholic fatty liver disease activity score (beta per allele in score units, -0.98; 95% CI, -1.54 to -0.41 [scores range from 0 to 8, with higher scores indicating more severe disease]). In human hepatoma cell lines challenged with oleate, CIDEB small interfering RNA knockdown prevented the buildup of large lipid droplets. CONCLUSIONS: Rare germline mutations in CIDEB conferred substantial protection from liver disease. (Funded by Regeneron Pharmaceuticals.).

Qualitative inquiry with primary care providers and specialists about adult weight management care and referrals.

Obesity is a highly prevalent disease and providers are expected to offer or refer patients for weight management yet increasingly fewer clinical visits address obesity. Challenges to offering care are known but less is known about referrals and how specialists who treat obesity-related comorbidities address care and referrals. This study explored perceptions of primary care providers (PCPs) and specialty providers regarding care and referrals for weight management, specifically referrals to programs in the community setting. A qualitative design was used to interview 33 PCPs (mean age 54 years) and 31 specialists (cardiology, gynecology, endocrinology, and orthopedics [mean age 62 years]) in the USA during 2019. Each interview was conducted by telephone, audio-recorded, and transcribed verbatim. Inductive analysis was used and followed the constant comparative method. Four themes emerged from the data including (a) Clinical guidelines and provider discretion influence obesity care; (b) Facilitators and barriers to discussing weight and small step strategies; (c) Informal referrals are made for weight management in community settings; and (d) Opportunities and challenges for integrating clinical and community services for weight management. Facilitating referrals to effective programs, ideally with a feedback loop could coordinate care and enhance accountability, but education, compliance, and cost issues need addressed. Care may be offered but not be well-aligned with clinical guidelines. Knowledge gaps regarding community programs' offerings and efficacy were evident. Referrals could be systematically promoted, facilitated, and tracked to advance weight management objectives.

Expression of taste signaling elements in jejunal tissue in subjects with obesity.

Taste-signaling proteins, which are expressed throughout the digestive tract, are involved in regulating metabolism and immunity. This study aimed to determine if these genes are expressed and altered in jejunal tissues from patients with extreme obesity who received bariatric surgery. Reverse transcription polymerase chain reaction revealed that phospholipase C beta 2 and transient receptor potential channel M5 expression was downregulated in the jejunum of patients with a body mass index above 50, whereas gustducin expression remained unchanged. Our data suggest that taste-signaling dysregulation might contribute to obesity.

Impact of Sustained Weight Loss on Cardiometabolic Outcomes.

Obesity increases the risk of developing type 2 diabetes, hypertension, and hyperlipidemia. We sought to determine the impact of obesity maintenance, weight regain, weight loss maintenance, and magnitudes of weight loss on future risk and time to developing these cardiometabolic conditions. This was a retrospective cohort study of adults receiving primary care at Geisinger Health System between 2001 and 2017. Using electronic health records, patients with ≥3-weight measurements over a 2-year index period were identified and categorized. Obesity maintainers (OM) had obesity (body mass index ≥30 kg/m²) and maintained their weight within ±3% from baseline (reference group). Both weight loss rebounders (WLR) and weight loss maintainers (WLM) had obesity at baseline and lost >5% body weight in year 1; WLR regained ≥20% of weight loss by end of year 2 and WLM maintained ≥80% of weight loss. Incident type 2 diabetes, hypertension, and hyperlipidemia, and time-to-outcome were determined for each study group and by weight loss category for WLM. Of the 63,567 patients included, 67% were OM, 19% were WLR, and 14% were WLM. The mean duration of follow-up was 6.6 years (SD, 3.9). Time until the development of electronic health record-documented type 2 diabetes, hypertension, and hyperlipidemia was longest for WLM and shortest for OM (log-rank test p <0.0001). WLM had the lowest incident type 2 diabetes (adjusted hazard ratio [HR] 0.676 [95% confidence interval [CI] 0.617 to 0.740]; p <0.0001), hypertension (adjusted HR 0.723 [95% CI 0.655 to 0.799]; p <0.0001), and hyperlipidemia (adjusted HR 0.864 [95% CI 0.803 to 0.929]; p <0.0001). WLM with the greatest weight loss (>15%) had a longer time to develop any of the outcomes compared with those with the least amount of weight loss (<7%) (p <0.0001). In an integrated delivery network population, sustained weight loss was associated with a delayed onset of cardiometabolic diseases, particularly with a greater magnitude of weight loss.

Case presentation and panel discussion: Cardiometabolic risk mitigation.

The worldwide increase in the prevalence of obesity and adiposity-related comorbidities has required a novel approach to cardiometabolic risk mitigation focused on the key mechanistic drivers of disease. The current manuscript presents the case of a 74-year-old male with obesity complicated by coronary artery disease, hypertriglyceridemia, hypertension, nonalcoholic fatty liver disease, obstructive sleep apnea, and type 2 diabetes. Expert panelists discuss optimal diagnostic and treatment strategies focused on lifestyle modifications including dietary interventions such as the Mediterranean dietary pattern, medications that target multiple drivers of disease, as well as procedural options.

Effects of sustained weight loss on outcomes associated with obesity comorbidities and healthcare resource utilization.

OBJECTIVE: Determine the impact of long-term non-surgical weight loss maintenance on clinical relevance for osteoarthritis, cancer, opioid use, and depression/anxiety and healthcare resource utilization. METHODS: A cohort of adults receiving primary care within Geisinger Health System between 2001-2017 was retrospectively studied. Patients with ≥3 weight measurements in the two-year index period and obesity at baseline (BMI ≥30 kg/m2) were categorized: Obesity Maintainers (reference group) maintained weight within +/-3%; Weight Loss Rebounders lost ≥5% body weight in year one, regaining ≥20% of weight loss in year two; Weight Loss Maintainers lost ≥5% body weight in year one, maintaining ≥80% of weight loss. Association with development of osteoarthritis, cancer, opioid use, and depression/anxiety, was assessed; healthcare resource utilization was quantified. Magnitude of weight loss among maintainers was evaluated for impact on health outcomes. RESULTS: In total, 63,567 patients were analyzed including 67% Obesity Maintainers, 19% Weight Loss Rebounders, and 14% Weight Loss Maintainers; median follow-up was 9.7 years. Time until osteoarthritis onset was delayed for Weight Loss Maintainers compared to Obesity Maintainers (Logrank test p <0.0001). Female Weight Loss Maintainers had a 19% and 24% lower risk of developing any cancer (p = 0.0022) or obesity-related cancer (p = 0.0021), respectively. No significant trends were observed for opioid use. Weight loss Rebounders and Maintainers had increased risk (14% and 25%) of future treatment for anxiety/depression (both <0.0001). Weight loss maintenance of >15% weight loss was associated with the greatest decrease in incident osteoarthritis. Healthcare resource utilization was significantly higher for Weight Loss Rebounders and Maintainers compared to Obesity Maintainers. Increased weight loss among Weight Loss Maintainers trended with lower overall healthcare resource utilization, except for hospitalizations. CONCLUSIONS: In people with obesity, sustained weight loss was associated with greater clinical benefits than regained short-term weight loss and obesity maintenance. Higher weight loss magnitudes were associated with delayed onset of osteoarthritis and led to decreased healthcare utilization.

"Bioelectrical impedance analysis in managing sarcopenic obesity in NAFLD".

INTRODUCTION: Sarcopenic obesity and its association with nonalcoholic fatty liver disease (NAFLD) is under-recognized by many healthcare providers in Western medicine due to the lack of awareness and diagnostic guidelines. The result is delayed recognition and treatment, which leads to further health deterioration and increased healthcare costs. Sarcopenic obesity is characterized by the presence of increased fat mass in combination with muscle catabolism related to chronic inflammation and/or inactivity. Previous research has recommended evaluating body composition and physical function performance to adequately diagnose sarcopenic obesity. Body composition analysis can be performed by imaging applications through magnetic resonance imaging, computed tomography, and dual-energy x-ray absorptiometry. Due to the cost of each device and radiation exposure for patients as evidenced in all three modalities, bioelectrical impedance analysis offers a noninvasive approach capable of providing quick and reliable estimates of lean body and fat mass. METHODS AND RESULTS: This review analyzes the current evidence-based literature, indicating a lower skeletal muscle mass and increased visceral adipose tissue correlation to the advancement of fibrosis in fatty liver disease. CONCLUSION: Given the substantial promising research conducted in predominantly Asian populations regarding body tissue distribution and NAFLD, additional prospective research is needed to extend these findings in Western populations.

Differential DNA methylation and changing cell-type proportions as fibrotic stage progresses in NAFLD.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is characterized by changes in cell composition that occur throughout disease pathogenesis, which includes the development of fibrosis in a subset of patients. DNA methylation (DNAm) is a plausible mechanism underlying these shifts, considering that DNAm profiles differ across tissues and cell types, and DNAm may play a role in cell-type differentiation. Previous work investigating the relationship between DNAm and fibrosis in NAFLD has been limited by sample size and the number of CpG sites interrogated. RESULTS: Here, we performed an epigenome-wide analysis using Infinium MethylationEPIC array data from 325 individuals with NAFLD, including 119 with severe fibrosis and 206 with no histological evidence of fibrosis. After adjustment for latent confounders, we identified 7 CpG sites whose DNAm associated with fibrosis (p < 5.96 × 10-8). Analysis of RNA-seq data collected from a subset of individuals (N = 56) revealed that gene expression at 288 genes associated with DNAm at one or more of the 7 fibrosis-related CpGs. DNAm-based estimates of cell-type proportions showed that estimated proportions of natural killer cells increased, while epithelial cell proportions decreased with disease stage. Finally, we used an elastic net regression model to assess DNAm as a biomarker of fibrotic stage and found that our model predicted fibrosis with a sensitivity of 0.93 and provided information beyond a model based solely on cell-type proportions. CONCLUSION: These findings are consistent with DNAm as a mechanism underpinning or marking fibrosis-related shifts in cell composition and demonstrate the potential of DNAm as a possible biomarker of NAFLD fibrosis.

Iron deficiency is highly prevalent among candidates for metabolic surgery and may affect perioperative outcomes.

BACKGROUND: The presence of chronic low-grade inflammation, commonly identified in patients with severe obesity, alters iron homeostasis and indicators of iron status, fostering the development of updated guidelines for the diagnosis of iron deficiency (ID). Current recommended diagnostic thresholds for ID in obesity derived from expert opinion include a ferritin level of <30 ng/mL and/or transferrin saturation (TSAT) < 20%. Earlier studies of ID among candidates for metabolic surgery using low levels of ferritin or iron as diagnostic thresholds demonstrated a prevalence of 5%-20%. OBJECTIVES: Using the current recommended diagnostic thresholds for ID, this study measures the prevalence of ID in a large cohort of surgical candidates and its relationship to surgical outcomes. SETTING: Geisinger Medical Center, Danville, Pennsylvania. METHODS: The study cohort included 3,723 patients who underwent pre- operative nutritional assessment which included markers of iron nutrition over the period 2004-2018. RESULTS: The cohort included 2,988 women (80.3%) and 735 men (19.7%); body mass index: 49.4 ± 9 kg/m2. The diagnosis of ID was based on ferritin level <30 ng/mL (true ID) and/or TSAT < 20% representing a combination of true ID and inflammation (serum ferritin ≥ 30 ng/mL and TSAT < 20%). A total of 399 patients (10.8%) were anemic. A serum ferritin level of < 30 ng/mL was found in 488 patients (13%; 481 women and 7 men). Of these, 122 patients (25.2%) were also anemic. An additional 1,204 had serum ferritin ≥ 30 ng/mL and TSAT < 20%. Overall, 1,692 patients (45.4%) in this cohort had laboratory evidence of ID by current criteria that adjusts for the very high prevalence of inflammation. Men with serum ferritin levels ≥30 ng/mL with TSAT < 20% had an increased surgical length of stay. CONCLUSION: The prevalence of ID among surgical candidates (45.4%) is more than twice that identified as ID in earlier studies. ID was commonly identified in the absence of anemia. The most severe ID was found in those with a serum ferritin level <30 ng/mL and TSAT < 20%. ID in the presence of inflammation is often unrecognized and has implications regarding surgical outcomes after metabolic surgery.

Sequencing of 640,000 exomes identifies GPR75 variants associated with protection from obesity.

Large-scale human exome sequencing can identify rare protein-coding variants with a large impact on complex traits such as body adiposity. We sequenced the exomes of 645,626 individuals from the United Kingdom, the United States, and Mexico and estimated associations of rare coding variants with body mass index (BMI). We identified 16 genes with an exome-wide significant association with BMI, including those encoding five brain-expressed G protein-coupled receptors (CALCR, MC4R, GIPR, GPR151, and GPR75). Protein-truncating variants in GPR75 were observed in ~4/10,000 sequenced individuals and were associated with 1.8 kilograms per square meter lower BMI and 54% lower odds of obesity in the heterozygous state. Knock out of Gpr75 in mice resulted in resistance to weight gain and improved glycemic control in a high-fat diet model. Inhibition of GPR75 may provide a therapeutic strategy for obesity.

The Association between Poor Diet Quality, Physical Fatigability and Physical Function in the Oldest-Old from the Geisinger Rural Aging Study.

More perceived physical fatigability and poor diet quality are associated with impairments in physical function in older adults. However, the degree to which more perceived fatigability explains the association between poor diet quality and low physical function is unknown. We examined this relationship in 122 (66F, 56M) of the oldest-old participants from the Geisinger Rural Aging Study (GRAS). We used 24-h dietary recalls to assess the Healthy Eating Index (HEI), the Pittsburgh Fatigability Scale (PFS, 0-50) to assess perceived physical fatigability, and the PROMIS Physical Function 20a* to assess physical function. We grouped participants into three age categories: 80-84 (n = 51), 85-89 (n = 51), and 90+ (n = 20) years. Multiple linear regression revealed that a lower HEI was associated with higher PFS Physical score after adjusting for age group, sex, body mass index, and the number of medical conditions (p = 0.001). Several macro- and micro-nutrient intakes were also lower in those reporting more (≥15) compared to less (<15) perceived physical fatigability. Mediation analysis revealed that PFS Physical scores explained ~65% (p = 0.001) of the association between HEI total score and PROMIS19 Physical Function score. Poor diet quality may contribute to more perceived physical fatigability, which could exacerbate impairments in the oldest-old's physical function.