1 1952 76 EPIGENETIC AGE ACCELERATION AMONG SURVIVORS OF PEDIATRIC MEDULLOBLASTOMA AND PRIMITIVE NEUROECTODERMAL TUMOR. SURVIVORS OF CHILDHOOD CENTRAL NERVOUS SYSTEM (CNS) TUMORS EXPERIENCE EARLY-ONSET AGING-RELATED PHENOTYPES. DNA METHYLATION (DNAM) AGE IS AN EMERGING EPIGENETIC BIOMARKER OF PHYSIOLOGIC AGE AND MAY BE PREDICTIVE OF CHRONIC HEALTH CONDITIONS IN LONG-TERM SURVIVORS. THIS REPORT DESCRIBES THE COURSE OF EPIGENETIC AGE ACCELERATION USING POST-DIAGNOSIS BLOOD SAMPLES (MEDIAN: 3.9 YEARS POST-DIAGNOSIS; RANGE: 0.04-15.96) FROM 83 SURVIVORS OF PEDIATRIC CNS TUMORS. EPIGENETIC AGE ACCELERATION WAS DETECTED IN 72% OF PATIENTS, WITH AN AVERAGE DIFFERENCE BETWEEN CHRONOLOGIC AND DNAM AGE OF 2.58 YEARS (95% CI: 1.75-3.41, P < 0.001). TIME FROM DIAGNOSIS TO SAMPLE COLLECTION CORRELATED WITH THE MAGNITUDE OF EPIGENETIC AGE ACCELERATION. 2023 2 175 25 ACCELERATED AGING WITH HIV BEGINS AT THE TIME OF INITIAL HIV INFECTION. LIVING WITH HIV INFECTION IS ASSOCIATED WITH EARLY ONSET OF AGING-RELATED CHRONIC CONDITIONS, SOMETIMES DESCRIBED AS ACCELERATED AGING. EPIGENETIC DNA METHYLATION PATTERNS CAN EVALUATE ACCELERATION OF BIOLOGICAL AGE RELATIVE TO CHRONOLOGICAL AGE. THE IMPACT OF INITIAL HIV INFECTION ON FIVE EPIGENETIC MEASURES OF AGING WAS EXAMINED BEFORE AND APPROXIMATELY 3 YEARS AFTER HIV INFECTION IN THE SAME INDIVIDUALS (N=102). SIGNIFICANT EPIGENETIC AGE ACCELERATION (MEDIAN 1.9-4.8 YEARS) AND ESTIMATED TELOMERE LENGTH SHORTENING (ALL P 0.05). EPIGENETIC AGING WAS ASSOCIATED WITH GREATER EMOTIONAL STABILITY (R = -0.461, P = 0.027), CONSCIENTIOUSNESS (R = -0.549, P = 0.007), AND LOWER EXTRAVERSION (R = 0.414, P = 0.049) BUT NOT DEPRESSION OR AFFECT (P'S > 0.05). EPIGENETIC AGING WAS ALSO ASSOCIATED WITH LOWER EPISODIC (R = -0.698, P = 0.001) AND WORKING MEMORY (R = -0.760, P < 0.001). OUR FINDINGS SUGGEST THAT CHRONIC PAIN IS ASSOCIATED WITH ACCELERATED EPIGENETIC AGING IN HEALTHY, COMMUNITY-DWELLING OLDER INDIVIDUALS, AND FUTURE STUDIES WITH LARGER SAMPLES ARE NEEDED TO CONFIRM OUR FINDINGS. AN AGING BIOMARKER SUCH AS THE EPIGENETIC CLOCK MAY HELP IDENTIFY PEOPLE WITH CHRONIC PAIN AT GREATER RISK OF FUNCTIONAL DECLINE AND POORER HEALTH OUTCOMES. 2019 5 1537 22 DNA METHYLATION IN ADOLESCENTS WITH ANXIETY DISORDER: A LONGITUDINAL STUDY. ANXIETY DISORDERS (AD) TYPICALLY MANIFEST IN CHILDREN AND ADOLESCENTS AND MIGHT PERSIST INTO ADULTHOOD. HOWEVER, THERE ARE STILL FEW DATA CONCERNING EPIGENETIC MECHANISMS ASSOCIATED WITH ONSET, PERSISTENCE OR REMISSION OF AD OVER TIME. WE INVESTIGATED A COHORT OF ADOLESCENTS AND YOUNG ADULTS AT BASELINE (AGE; 13.19 +/- 2.38) AND AFTER 5 YEARS AND CLASSIFIED THEM ACCORDING TO THE AD DIAGNOSIS AND THEIR LONGITUDINAL TRAJECTORIES INTO 4 GROUPS: (1) TYPICALLY DEVELOPING COMPARISONS (TDC; CONTROL GROUP, N = 14); (2) INCIDENT (AD IN THE SECOND EVALUATION ONLY, N = 11); (3) PERSISTENT (AD IN BOTH EVALUATIONS, N = 14) AND (4) REMITTENT (AD IN THE FIRST EVALUATION ONLY, N = 8). DNA METHYLATION WAS EVALUATED WITH THE INFINIUM HUMANMETHYLATION450 BEADCHIP FROM SALIVA SAMPLES COLLECTED AT BOTH EVALUATIONS. GENE SET ENRICHMENT ANALYSIS WAS APPLIED TO CONSIDER BIOLOGICAL PATHWAYS. WE FOUND DECREASED DNA METHYLATION IN TDC GROUP WHILE THE CHRONIC CASES OF AD PRESENTED HYPERMETHYLATION IN CENTRAL NERVOUS SYSTEM DEVELOPMENT PATHWAYS. MOREOVER, WE SHOWED THAT THIS PERSISTENT GROUP ALSO PRESENTED HYPERMETHYLATION WHILE THE OTHER THREE GROUPS WERE ASSOCIATED WITH HYPOMETHYLATION IN NERVOUS SYSTEM DEVELOPMENT PATHWAY. INCIDENCE AND REMISSION GROUPS WERE ASSOCIATED WITH INCREASED AND DECREASED METHYLATION IN NEURON DEVELOPMENT PATHWAYS, RESPECTIVELY. LARGER STUDIES ARE LIKELY TO DETECT SPECIFIC GENES RELEVANT TO AD. 2018 6 4024 28 LUNG ALLOGRAFT EPITHELIUM DNA METHYLATION AGE IS ASSOCIATED WITH GRAFT CHRONOLOGIC AGE AND PRIMARY GRAFT DYSFUNCTION. ADVANCED DONOR AGE IS A RISK FACTOR FOR POOR SURVIVAL FOLLOWING LUNG TRANSPLANTATION. HOWEVER, RECENT WORK IDENTIFYING EPIGENETIC DETERMINANTS OF AGING HAS SHOWN THAT BIOLOGIC AGE MAY NOT ALWAYS REFLECT CHRONOLOGIC AGE AND THAT STRESSORS CAN ACCELERATE BIOLOGIC AGING. WE HYPOTHESIZED THAT LUNG ALLOGRAFTS THAT EXPERIENCED PRIMARY GRAFT DYSFUNCTION (PGD), CHARACTERIZED BY POOR OXYGENATION IN THE FIRST THREE POST-TRANSPLANT DAYS, WOULD HAVE INCREASED BIOLOGIC AGE. WE CULTURED AIRWAY EPITHELIAL CELLS ISOLATED BY TRANSBRONCHIAL BRUSH AT 1-YEAR BRONCHOSCOPIES FROM 13 SUBJECTS WITH SEVERE PGD AND 15 CONTROLS MATCHED ON AGE AND TRANSPLANT INDICATION. WE MEASURED EPIGENETIC AGE USING THE HORVATH EPIGENETIC CLOCK. LINEAR MODELS WERE USED TO DETERMINE THE ASSOCIATION OF AIRWAY EPIGENETIC AGE WITH CHRONOLOGIC AGES AND PGD STATUS, ADJUSTED FOR RECIPIENT PGD RISK FACTORS. SURVIVAL MODELS ASSESSED THE ASSOCIATION WITH CHRONIC LUNG ALLOGRAFT DYSFUNCTION (CLAD) OR DEATH. DISTRIBUTIONS OF PROMOTER METHYLATION WITHIN PATHWAYS WERE COMPARED BETWEEN GROUPS. DNA METHYLTRANSFERASE (DNMT) ACTIVITY WAS QUANTIFIED IN AIRWAY EPITHELIAL CELLS UNDER HYPOXIC OR NORMOXIC CONDITIONS. AIRWAY EPIGENETIC AGE APPEARED YOUNGER BUT WAS STRONGLY ASSOCIATED WITH THE AGE OF THE ALLOGRAFT (SLOPE 0.38 PER YEAR, 95% CI 0.27-0.48). THERE WAS NO CORRELATION BETWEEN EPIGENETIC AGE AND RECIPIENT AGE (P = 0.96). EPIGENETIC AGE WAS 6.5 YEARS GREATER (95% CI 1.7-11.2) IN SUBJECTS WHO HAD EXPERIENCED PGD, AND THIS EFFECT REMAINED SIGNIFICANT AFTER ADJUSTING FOR DONOR AND RECIPIENT CHARACTERISTICS (P = 0.03). EPIGENETIC AGE WAS NOT ASSOCIATED WITH CLAD-FREE SURVIVAL RISK (P = 0.11). ANALYSIS OF DIFFERENTIAL METHYLATION OF PROMOTERS OF KEY BIOLOGIC PATHWAYS REVEALED HYPOMETHYLATION IN REGIONS RELATED TO HYPOXIA, INFLAMMATION, AND METABOLISM-ASSOCIATED PATHWAYS. ACCORDINGLY, AIRWAY EPITHELIAL CELLS CULTURED IN HYPOXIC CONDITIONS SHOWED SUPPRESSED DNMT ACTIVITY. WHILE AIRWAY METHYLATION AGE WAS PRIMARILY DETERMINED BY DONOR CHRONOLOGIC AGE, EARLY INJURY IN THE FORM OF PGD WAS ASSOCIATED WITH INCREASED ALLOGRAFT EPIGENETIC AGE. THESE DATA SHOW HOW PGD MIGHT SUPPRESS KEY PROMOTER METHYLATION RESULTING IN LONG-TERM IMPACTS ON THE ALLOGRAFT. 2021 7 177 24 ACCELERATED EPIGENETIC AGING AND INFLAMMATORY/IMMUNOLOGICAL PROFILE (IPAGE) IN PATIENTS WITH CHRONIC KIDNEY DISEASE. CHRONIC KIDNEY DISEASE (CKD) IS DEFINED BY A REDUCED ESTIMATED GLOMERULAR FILTRATION RATE (EGFR). THIS FAILURE CAN BE RELATED TO A PHENOTYPE OF ACCELERATED AGING. IN THIS WORK, WE CONSIDERED 76 PATIENTS WITH END-STAGE RENAL DISEASE (ESRD) AND 83 HEALTHY CONTROLS. WE CONCOMITANTLY EVALUATED FOR THE FIRST TIME TWO MEASURES THAT CAN BE INFORMATIVE OF THE RATE OF AGING, I.E., WHOLE BLOOD DNA METHYLATION USING THE ILLUMINA INFINIUM EPIC ARRAY AND PLASMA LEVELS OF A SELECTION OF INFLAMMATORY/IMMUNOLOGICAL PROTEINS USING MULTIPLEX IMMUNOASSAYS. FIRST OF ALL, WE DEMONSTRATED ACCELERATED AGING IN TERMS OF THE MOST COMMON EPIGENETIC AGE ESTIMATORS IN CKD PATIENTS. MOREOVER, WE DEVELOPED A NEW CLOCK/PREDICTOR OF AGE BASED ON THE INFLAMMATORY/IMMUNOLOGICAL PROFILE (IPAGE) AND IDENTIFIED THE INFLAMMATORY/IMMUNOLOGICAL BIOMARKERS DIFFERENTIALLY EXPRESSED BETWEEN CASES AND CONTROLS. IPAGE APPEARED TO BE MORE SENSITIVE THAN EPIGENETIC CLOCKS IN QUANTIFYING THE ACCELERATED AGING PHENOTYPE OF ESRD PATIENTS. INTERESTINGLY, WE DID NOT FIND ANY CORRELATION BETWEEN THE AGE ACCELERATION EVALUATED ACCORDING TO THE EPIGENETIC CLOCKS AND IPAGE IN EITHER THE ESRD GROUP OR THE CONTROL GROUP. ON THE WHOLE, OUR DATA SHOW A CONSISTENT ACCELERATED AGING PHENOTYPE IN ESRD PATIENTS, WHICH IS BETTER APPRECIATED BY QUANTIFYING THE UNDERLYING INFLAMMATORY PROCESSES (INFLAMMAGING) BY IPAGE THAN BY USING EPIGENETIC CLOCKS. 2022 8 4502 23 MORTALITY ASSOCIATIONS WITH DNA METHYLATION-BASED BIOLOGICAL AGING AND PHYSICAL FUNCTIONING MEASURES ACROSS A 20-YEAR FOLLOW-UP PERIOD. BACKGROUND: MEASURES OF BIOLOGICAL AGING RANGE FROM DNA METHYLATION (DNAM)-BASED ESTIMATES TO MEASURES OF PHYSICAL ABILITIES. THE PURPOSE OF THIS STUDY WAS TO COMPARE DNAM- AND PHYSICAL FUNCTIONING-BASED MEASURES OF BIOLOGICAL AGING IN PREDICTING MORTALITY. METHODS: WE STUDIED 63- TO 76-YEAR-OLD WOMEN (N = 395) FROM THE FINNISH TWIN STUDY ON AGING (FITSA). PARTICIPANTS' BIOLOGICAL AGE (EPIGENETIC CLOCKS DNAM GRIMAGE AND DUNEDINPACE) WAS ESTIMATED USING BLOOD DNAM DATA. TESTS OF PHYSICAL FUNCTIONING CONDUCTED UNDER STANDARDIZED LABORATORY CONDITIONS INCLUDED THE TIMED UP AND GO (TUG) TEST AND 10-M WALK TEST. MORTALITY HAZARD RATIOS WERE CALCULATED PER EVERY 1 STANDARD DEVIATION (SD) INCREASE IN THE PREDICTOR. COX REGRESSION MODELS WERE CONDUCTED FOR INDIVIDUALS AND TWIN PAIRS, THE LATTER CONTROLLING FOR UNDERLYING GENETIC EFFECTS. THE MODELS WERE ADJUSTED FOR KNOWN LIFESTYLE PREDICTORS OF MORTALITY. RESULTS: DURING THE FOLLOW-UP PERIOD (MEAN 17.0 YEARS, RANGE 0.2-20.3), 187 PARTICIPANTS DIED. IN BOTH THE INDIVIDUAL-BASED AND PAIRWISE ANALYSES, GRIMAGE AND BOTH FUNCTIONAL BIOMARKERS OF AGING WERE ASSOCIATED WITH MORTALITY INDEPENDENT OF FAMILY RELATEDNESS, CHRONOLOGICAL AGE, PHYSICAL ACTIVITY, BODY MASS INDEX, SMOKING, EDUCATION, OR CHRONIC DISEASES. IN A MODEL INCLUDING BOTH THE DNAM-BASED MEASURES AND FUNCTIONAL BIOMARKERS OF AGING, GRIMAGE AND TUG REMAINED PREDICTIVE. CONCLUSIONS: THE FINDINGS SUGGEST THAT DNAM GRIMAGE AND THE TUG TEST ARE STRONG PREDICTORS OF MORTALITY INDEPENDENT OF EACH OTHERS AND GENETIC INFLUENCES. DNAM-BASED MEASURES AND FUNCTIONAL TESTS CAPTURE DIFFERENT ASPECTS OF THE AGING PROCESS AND THUS COMPLEMENT EACH OTHER AS MEASURES OF BIOLOGICAL AGING IN PREDICTING MORTALITY. 2023 9 1849 22 EIGHT WEEKS OF PHYSICAL TRAINING DECREASES 2 YEARS OF DNA METHYLATION AGE OF SEDENTARY WOMEN. PURPOSE: THE ACCELERATION OF EPIGENETIC AGE IS A PREDICTOR OF MORTALITY AND CONTRIBUTES TO THE INCREASE IN CHRONIC DISEASES. ADHERENCE TO A HEALTHY LIFESTYLE IS A STRATEGY TO REDUCE EPIGENETIC AGE. THE PRESENT STUDY AIMED TO DETERMINE WHETHER EIGHT WEEKS OF COMBINED (AEROBIC AND STRENGTH) TRAINING (CT) CAN INFLUENCE THE EPIGENETIC AGE OF WOMEN BETWEEN 50 AND 70 YEARS OLD AND THE DIFFERENCES IN SITES AND METHYLATED REGIONS. METHODS: EIGHTEEN WOMEN (AAR(LOW): LOWER AGE ACCELERATION RESIDUAL, N = 10; AAR(HIGH): HIGHER AGE ACCELERATION RESIDUAL, N = 8) PARTICIPATED IN A COMBINED EXERCISE TRAINING PROGRAM (60 MINUTES, 3X A WEEK) FOR EIGHT WEEKS. DNA WAS EXTRACTED FROM WHOLE BLOOD USING THE SALTING OUT TECHNIQUE. DNA METHYLATION WAS PERFORMED USING THE ARRAY TECHNIQUE (ILLUMINA'S INFINIUM METHYLATION BEADCHIP 850K). WE USED THE DNA METHYLATION AGE CALCULATOR PLATFORM TO CALCULATE THE BIOLOGICAL EPIGENETIC AGE. TWO-WAY ANOVA FOLLOWED BY FISHER LSD POSTHOC WAS APPLIED, ADOPTING P < .05. RESULTS: AFTER EIGHT WEEKS OF CT, THERE WERE NO CHANGES TO THE EPIGENETIC AGE ACCELERATION FOR THE AAR(LOW) GROUP (PRE: -2.3 +/- 3.2 TO POST: -2.3 +/- 3.6). HOWEVER, THE AAR(HIGH) GROUP SIGNIFICANTLY DECREASED THE AGE ACCELERATION (PRE: 3.6 +/- 2.6 TO POST: 2.2 +/- 2.7) (GROUP EFFECT, P = .01; TIME EFFECT, P = .31; GROUP VS. TIME EFFECT, P = .005). CONCLUSION: CT FOR EIGHT WEEKS BENEFITS THE EPIGENETIC CLOCK OF WOMEN WITH THE MOST ACCELERATED AGE. 2023 10 2485 24 EPIGENETIC-BASED AGE ACCELERATION IN A REPRESENTATIVE SAMPLE OF OLDER AMERICANS: ASSOCIATIONS WITH AGING-RELATED MORBIDITY AND MORTALITY. BIOMARKERS DEVELOPED FROM DNA METHYLATION (DNAM) DATA ARE OF GROWING INTEREST AS PREDICTORS OF HEALTH OUTCOMES AND MORTALITY IN OLDER POPULATIONS. HOWEVER, IT IS UNKNOWN HOW EPIGENETIC AGING FITS WITHIN THE CONTEXT OF KNOWN SOCIOECONOMIC AND BEHAVIORAL ASSOCIATIONS WITH AGING-RELATED HEALTH OUTCOMES IN A LARGE, POPULATION-BASED, AND DIVERSE SAMPLE. THIS STUDY USES DATA FROM A REPRESENTATIVE, PANEL STUDY OF US OLDER ADULTS TO EXAMINE THE RELATIONSHIP BETWEEN DNAM-BASED AGE ACCELERATION MEASURES IN THE PREDICTION OF CROSS-SECTIONAL AND LONGITUDINAL HEALTH OUTCOMES AND MORTALITY. WE EXAMINE WHETHER RECENT IMPROVEMENTS TO THESE SCORES, USING PRINCIPAL COMPONENT (PC)-BASED MEASURES DESIGNED TO REMOVE SOME OF THE TECHNICAL NOISE AND UNRELIABILITY IN MEASUREMENT, IMPROVE THE PREDICTIVE CAPABILITY OF THESE MEASURES. WE ALSO EXAMINE HOW WELL DNAM-BASED MEASURES PERFORM AGAINST WELL-KNOWN PREDICTORS OF HEALTH OUTCOMES SUCH AS DEMOGRAPHICS, SES, AND HEALTH BEHAVIORS. IN OUR SAMPLE, AGE ACCELERATION CALCULATED USING "SECOND AND THIRD GENERATION CLOCKS," PHENOAGE, GRIMAGE, AND DUNEDINPACE, IS CONSISTENTLY A SIGNIFICANT PREDICTOR OF HEALTH OUTCOMES INCLUDING CROSS-SECTIONAL COGNITIVE DYSFUNCTION, FUNCTIONAL LIMITATIONS AND CHRONIC CONDITIONS ASSESSED 2 Y AFTER DNAM MEASUREMENT, AND 4-Y MORTALITY. PC-BASED EPIGENETIC AGE ACCELERATION MEASURES DO NOT SIGNIFICANTLY CHANGE THE RELATIONSHIP OF DNAM-BASED AGE ACCELERATION MEASURES TO HEALTH OUTCOMES OR MORTALITY COMPARED TO EARLIER VERSIONS OF THESE MEASURES. WHILE THE USEFULNESS OF DNAM-BASED AGE ACCELERATION AS A PREDICTOR OF LATER LIFE HEALTH OUTCOMES IS QUITE CLEAR, OTHER FACTORS SUCH AS DEMOGRAPHICS, SES, MENTAL HEALTH, AND HEALTH BEHAVIORS REMAIN EQUALLY, IF NOT MORE ROBUST, PREDICTORS OF LATER LIFE OUTCOMES. 2023 11 1351 31 DETERMINATION OF SALIVA EPIGENETIC AGE IN INFANCY, AND ITS ASSOCIATION WITH PARENTAL SOCIO-ECONOMIC CHARACTERISTICS AND PREGNANCY OUTCOMES. EPIGENETIC AGE ACCELERATION (AA) HAS BEEN ASSOCIATED WITH ADVERSE ENVIRONMENTAL EXPOSURES AND MANY CHRONIC CONDITIONS. WE ESTIMATED, IN THE NINFEA BIRTH COHORT, INFANT SALIVA EPIGENETIC AGE, AND INVESTIGATED WHETHER PARENTAL SOCIO-ECONOMIC POSITION (SEP) AND PREGNANCY OUTCOMES ARE ASSOCIATED WITH INFANT EPIGENETIC AA. A TOTAL OF 139 SALIVA SAMPLES COLLECTED AT ON AVERAGE 10.8 (RANGE 7-17) MONTHS WERE USED TO ESTIMATE HORVATH'S DNA METHYLATION AGE. EPIGENETIC AA WAS DEFINED AS THE RESIDUAL FROM A LINEAR REGRESSION OF EPIGENETIC AGE ON CHRONOLOGICAL AGE. LINEAR REGRESSION MODELS WERE USED TO TEST THE ASSOCIATIONS OF PARENTAL SEP AND PREGNANCY OUTCOMES WITH SALIVA EPIGENETIC AA. A MODERATE POSITIVE ASSOCIATION WAS FOUND BETWEEN DNA METHYLATION AGE AND CHRONOLOGICAL AGE, WITH THE MEDIAN ABSOLUTE DIFFERENCE OF 6.8 MONTHS (STANDARD DEVIATION [SD] 3.9). THE EVIDENCE OF THE ASSOCIATION BETWEEN THE INDICATORS OF LOW SEP AND EPIGENETIC AA WAS WEAK; INFANTS BORN TO UNEMPLOYED MOTHERS OR WITH LOW EDUCATION HAD ON AVERAGE 1 MONTH HIGHER EPIGENETIC AGE THAN INFANTS OF MOTHERS WITH HIGH EDUCATION AND EMPLOYMENT (COEFFICIENT 0.78 MONTHS, 95% CONFIDENCE INTERVALS [CIS]: -0.79 TO 2.34 FOR LOW/MEDIUM EDUCATION; 0.96, 95% CI: -1.81 TO 3.73 FOR UNEMPLOYMENT). THERE WAS NO EVIDENCE FOR ASSOCIATION OF GESTATIONAL AGE, BIRTHWEIGHT OR CAESAREAN SECTION WITH INFANT EPIGENETIC AA. USING THE HORVATH'S METHOD, DNA METHYLATION AGE CAN BE FAIRLY ACCURATELY PREDICTED FROM SALIVA SAMPLES ALREADY IN THE FIRST MONTHS OF LIFE. THIS STUDY DID NOT REVEAL CLEAR ASSOCIATIONS BETWEEN EITHER PREGNANCY OUTCOMES OR PARENTAL SOCIO-ECONOMIC CHARACTERISTICS AND INFANT SALIVA EPIGENETIC AA. 2021 12 6508 26 TRAJECTORIES OF INFLAMMATORY BIOMARKERS OVER THE EIGHTH DECADE AND THEIR ASSOCIATIONS WITH IMMUNE CELL PROFILES AND EPIGENETIC AGEING. BACKGROUND: EPIGENETIC AGE ACCELERATION (AN OLDER METHYLATION AGE COMPARED TO CHRONOLOGICAL AGE) CORRELATES STRONGLY WITH VARIOUS AGE-RELATED MORBIDITIES AND MORTALITY. CHRONIC SYSTEMIC INFLAMMATION IS THOUGHT TO BE A HALLMARK OF AGEING, BUT THE RELATIONSHIP BETWEEN AN INCREASED EPIGENETIC AGE AND THIS LIKELY KEY PHENOTYPE OF AGEING HAS NOT YET BEEN EXTENSIVELY INVESTIGATED. METHODS: WE MODELLED THE TRAJECTORIES OF THE INFLAMMATORY BIOMARKERS C-REACTIVE PROTEIN (CRP; MEASURED USING BOTH A HIGH- AND LOW-SENSITIVITY ASSAY) AND INTERLEUKIN-6 (IL-6) OVER THE EIGHTH DECADE IN THE LOTHIAN BIRTH COHORT 1936. USING LINEAR MIXED MODELS, WE INVESTIGATED THE ASSOCIATION BETWEEN CRP AND IMMUNE CELL PROFILES IMPUTED FROM THE METHYLATION DATA AND EXAMINED THE CROSS-SECTIONAL AND LONGITUDINAL ASSOCIATION BETWEEN THE INFLAMMATORY BIOMARKERS AND TWO MEASURES OF EPIGENETIC AGE ACCELERATION, DERIVED FROM THE HORVATH AND HANNUM EPIGENETIC CLOCKS. RESULTS: WE FOUND THAT LOW-SENSITIVITY CRP DECLINED, HIGH-SENSITIVITY CRP DID NOT CHANGE, AND IL-6 INCREASED OVER TIME WITHIN THE COHORT. CRP LEVELS INVERSELY ASSOCIATED WITH CD8+T CELLS AND CD4+T CELLS AND POSITIVELY ASSOCIATED WITH SENESCENT CD8+T CELLS, PLASMABLASTS AND GRANULOCYTES. CROSS-SECTIONALLY, THE HANNUM, BUT NOT THE HORVATH, MEASURE OF AGE ACCELERATION WAS POSITIVELY ASSOCIATED WITH EACH OF THE INFLAMMATORY BIOMARKERS, INCLUDING A RESTRICTED MEASURE OF CRP (