1 1746 110 EARLY LIFE ADVERSITY, PUBERTAL TIMING, AND EPIGENETIC AGE ACCELERATION IN ADULTHOOD. BACKGROUND: GIVEN ASSOCIATIONS LINKING EARLY LIFE ADVERSITY, PUBERTAL TIMING, AND BIOLOGICAL AGING, WE EXAMINED THE DIRECT AND INDIRECT EFFECTS OF EARLY LIFE TRAUMA ON ADULT BIOLOGICAL AGING (VIA AGE OF MENARCHE). METHODS: PARTICIPANTS WERE PREMENOPAUSAL WOMEN (N = 183). PATH MODELS EVALUATED WHETHER EARLY LIFE TRAUMA PREDICTED EARLY PUBERTAL TIMING AND THEREBY, ADULT EPIGENETIC AGE ACCELERATION (INDEXED VIA FOUR EPIGENETIC CLOCKS: HORVATH DNAM AGE, HANNUM DNAM AGE, DNAM PHENOAGE, AND DNAM GRIMAGE). SECONDARY ANALYSES EXPLORED THE EFFECTS OF TYPE OF TRAUMA (ABUSE AND NEGLECT) AND ADULT CHRONIC STRESS STATUS (CAREGIVER OF CHILD WITH AUTISM AND NON-CAREGIVER). RESULTS: EARLY LIFE TRAUMA AND EARLIER AGE AT MENARCHE INDEPENDENTLY PREDICTED ACCELERATED AGING BASED ON ONE OF THE FOUR EPIGENETIC CLOCKS, DNAM GRIMAGE, THOUGH EARLY LIFE TRAUMA WAS NOT ASSOCIATED WITH AGE OF MENARCHE. CHILDHOOD ABUSE, BUT NOT NEGLECT, PREDICTED FASTER EPIGENETIC AGING; RESULTS DID NOT DIFFER BY CHRONIC STRESS STATUS. CONCLUSIONS: EARLY TRAUMA AND EARLY MENARCHE APPEAR TO EXERT INDEPENDENT EFFECTS ON DNAM GRIMAGE, WHICH HAS BEEN SHOWN TO BE THE STRONGEST EPIGENETIC PREDICTOR OF MORTALITY RISK. THIS STUDY IDENTIFIES A POTENTIAL CORRELATE OR DETERMINANT OF ACCELERATED EPIGENETIC AGING-MENARCHEAL AGE. FUTURE RESEARCH SHOULD ADDRESS THE LIMITATIONS OF THIS STUDY BY USING RACIALLY DIVERSE SAMPLES. 2021 2 5395 37 REDUCED EPIGENETIC AGE IN OLDER ADULTS WITH HIGH SENSE OF PURPOSE IN LIFE. PSYCHOSOCIAL RISK FACTORS HAVE BEEN LINKED WITH ACCELERATED EPIGENETIC AGING, BUT LITTLE IS KNOWN ABOUT WHETHER PSYCHOSOCIAL RESILIENCE FACTORS (EG, SENSE OF PURPOSE IN LIFE) MIGHT REDUCE EPIGENETIC AGE ACCELERATION. IN THIS STUDY, WE TESTED IF OLDER ADULTS WHO EXPERIENCE HIGH LEVELS OF PURPOSE MIGHT SHOW REDUCED EPIGENETIC AGE ACCELERATION. WE EVALUATED THE RELATIONSHIP BETWEEN PURPOSE AND EPIGENETIC AGE ACCELERATION AS MEASURED BY 13 DNA METHYLATION (DNAM) "EPIGENETIC CLOCKS" ASSESSED IN 1 572 OLDER ADULTS FROM THE HEALTH AND RETIREMENT STUDY (MEAN AGE 70 YEARS). WE QUANTIFIED THE TOTAL ASSOCIATION BETWEEN PURPOSE AND DNAM AGE ACCELERATION AS WELL AS THE EXTENT TO WHICH THAT TOTAL ASSOCIATION MIGHT BE ATTRIBUTABLE TO DEMOGRAPHIC FACTORS, CHRONIC DISEASE, OTHER PSYCHOSOCIAL VARIABLES (EG, POSITIVE AFFECT), AND HEALTH-RELATED BEHAVIORS (HEAVY DRINKING, SMOKING, PHYSICAL ACTIVITY, AND BODY MASS INDEX [BMI]). PURPOSE IN LIFE WAS ASSOCIATED WITH REDUCED EPIGENETIC AGE ACCELERATION ACROSS 4 "SECOND-GENERATION" DNAM CLOCKS OPTIMIZED FOR PREDICTING HEALTH AND LONGEVITY (FALSE DISCOVERY RATE [FDR] Q < 0.0001: PHENOAGE, GRIMAGE, ZHANG EPIGENETIC MORTALITY INDEX; FDR Q < 0.05: DUNEDINPOAM). THESE ASSOCIATIONS WERE INDEPENDENT OF DEMOGRAPHIC AND PSYCHOSOCIAL FACTORS, BUT SUBSTANTIALLY ATTENUATED AFTER ADJUSTING FOR HEALTH-RELATED BEHAVIORS (DRINKING, SMOKING, PHYSICAL ACTIVITY, AND BMI). PURPOSE SHOWED NO SIGNIFICANT ASSOCIATION WITH 9 "FIRST-GENERATION" DNAM EPIGENETIC CLOCKS TRAINED ON CHRONOLOGICAL AGE. OLDER ADULTS WITH GREATER PURPOSE IN LIFE SHOW "YOUNGER" DNAM EPIGENETIC AGE ACCELERATION. THESE RESULTS MAY BE DUE IN PART TO ASSOCIATED DIFFERENCES IN HEALTH-RELATED BEHAVIORS. RESULTS SUGGEST NEW OPPORTUNITIES TO REDUCE BIOLOGICAL AGE ACCELERATION BY ENHANCING PURPOSE AND ITS BEHAVIORAL SEQUELAE IN LATE ADULTHOOD. 2023 3 2485 32 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 4 2734 39 EXPLORING THE RELATIONSHIP BETWEEN DNA METHYLATION AGE MEASURES AND PSYCHONEUROLOGICAL SYMPTOMS IN WOMEN WITH EARLY-STAGE BREAST CANCER. PURPOSE: THE EPIGENETIC CLOCK HAS BEEN ACKNOWLEDGED AS AN INDICATOR FOR MOLECULAR AGING, BUT FEW STUDIES HAVE EXAMINED POSSIBLE ASSOCIATIONS OF DNA METHYLATION (DNAM) AGE OR AGE ACCELERATION (AA) WITH SYMPTOM BURDEN IN INDIVIDUALS WHO ARE TREATED FOR CANCER. THIS STUDY EXPLORED THE ASSOCIATION OF DNAM AGE OR AA WITH PSYCHONEUROLOGICAL (PN) SYMPTOMS, INCLUDING COGNITIVE IMPAIRMENT, FATIGUE, SLEEP DISTURBANCES, PAIN, AND DEPRESSIVE SYMPTOMS, IN BREAST CANCER SURVIVORS OVER A 2-YEAR PERIOD. METHODS: WE MEASURED PN SYMPTOMS USING RELIABLE INSTRUMENTS AND DNAM LEVELS BY INFINIUM HUMANMETHYLATION450K BEADCHIP (N = 72). DNAM AGE WAS CALCULATED BY THE HORVATH, GRIM, AND HANNUM-BASED INTRINSIC AND EXTRINSIC AGE ESTIMATIONS. AA WAS DEFINED BY THE RESIDUAL REGRESSING ESTIMATED EPIGENETIC AGE ON CHRONOLOGICAL AGE. MIXED REGRESSION MODELS WERE FITTED FOR AA AND CHANGES IN AA TO STUDY THE ASSOCIATION OVER TIME. SEPARATE LINEAR REGRESSION MODELS AND A MIXED-EFFECTS MODEL WERE FITTED FOR AA AT EACH TIME POINT. RESULTS: HORVATH-AA, GRIM-AA, AND EXTRINSIC EPIGENETIC AA WERE SIGNIFICANTLY CHANGED OVER TIME, WHILE INTRINSIC EPIGENETIC AA DID NOT EXHIBIT ANY TEMPORAL CHANGES. INCREASED AA WAS ASSOCIATED WITH GREATER ANXIETY AND FATIGUE, AS WELL AS WORSE COGNITIVE MEMORY, ADJUSTING FOR RACE, BMI, INCOME, CHEMOTHERAPY, RADIATION THERAPY, AND CHRONOLOGICAL AGE. INCREASED DNAM AGE WAS ASSOCIATED WITH GREATER ANXIETY OVER 2 YEARS. CONCLUSION: OUR FINDINGS SUGGEST DNAM AGE AND AA MAY BE ASSOCIATED WITH PN SYMPTOMS OVER THE COURSE OF CANCER TREATMENT AND SURVIVORSHIP. SOME PN SYMPTOMS MAY BE AMENABLE TO PREVENTIVE INTERVENTIONS TARGETED TO EPIGENETIC CLOCKS THAT INFLUENCE AGING-ASSOCIATED PROCESSES. 2022 5 1957 36 EPIGENETIC AGE PREDICTORS IN COMMUNITY-DWELLING ADULTS WITH HIGH IMPACT KNEE PAIN. GERONTOLOGICAL RESEARCH REVEALS CONSIDERABLE INTERINDIVIDUAL VARIABILITY IN AGING PHENOTYPES, AND EMERGING EVIDENCE SUGGESTS THAT HIGH IMPACT CHRONIC PAIN MAY BE ASSOCIATED WITH VARIOUS ACCELERATED BIOLOGICAL AGING PROCESSES. IN PARTICULAR, EPIGENETIC AGING IS A ROBUST PREDICTOR OF HEALTH-SPAN AND DISABILITY COMPARED TO CHRONOLOGICAL AGE ALONE. THE CURRENT STUDY AIMED TO DETERMINE WHETHER SEVERAL EPIGENETIC AGING BIOMARKERS WERE ASSOCIATED WITH HIGH IMPACT CHRONIC PAIN IN MIDDLE TO OLDER AGE ADULTS (44-78 YEARS OLD). PARTICIPANTS (N = 213) UNDERWENT A BLOOD DRAW, DEMOGRAPHIC, PSYCHOSOCIAL, PAIN AND FUNCTIONAL ASSESSMENTS. WE ESTIMATED FIVE EPIGENETIC CLOCKS AND CALCULATED THE DIFFERENCE BETWEEN EPIGENETIC AGE AND CHRONOLOGICAL AGE, WHICH HAS BEEN PREVIOUSLY REPORTED TO PREDICT OVERALL MORTALITY RISK, AS WELL AS INCLUDED ADDITIONAL DERIVED VARIABLES OF EPIGENETIC AGE PREVIOUSLY ASSOCIATED WITH PAIN. THERE WERE SIGNIFICANT DIFFERENCES ACROSS PAIN IMPACT GROUPS IN THREE OUT OF THE FIVE EPIGENETIC CLOCKS EXAMINED (DNAMAGE, DNAMPHENOAGE AND DNAMGRIMAGE), INDICATING THAT PAIN-RELATED DISABILITY DURING THE PAST 6 MONTHS WAS ASSOCIATED WITH MARKERS OF EPIGENETIC AGING. ONLY DNAMPHENOAGE AND DNAMGRIMAGE WERE ASSOCIATED WITH HIGHER KNEE PAIN INTENSITY DURING THE PAST 48 H. FINALLY, PAIN CATASTROPHIZING, DEPRESSIVE SYMPTOMATOLOGY AND MORE NEUROPATHIC PAIN SYMPTOMS WERE SIGNIFICANTLY ASSOCIATED WITH AN OLDER EPIGENOME IN ONLY ONE OF THE FIVE EPIGENETIC CLOCKS (I.E. DNAMGRIMAGE) AFTER CORRECTING FOR MULTIPLE COMPARISONS (CORRECTED P'S < 0.05). GIVEN THE SCANT LITERATURE IN RELATION TO EPIGENETIC AGING AND THE COMPLEX EXPERIENCE OF PAIN, ADDITIONAL RESEARCH IS NEEDED TO UNDERSTAND WHETHER EPIGENETIC AGING MAY HELP IDENTIFY PEOPLE WITH CHRONIC PAIN AT GREATER RISK OF FUNCTIONAL DECLINE AND POORER HEALTH OUTCOMES. 2022 6 1780 35 EDUCATION AND LIFESTYLE FACTORS ARE ASSOCIATED WITH DNA METHYLATION CLOCKS IN OLDER AFRICAN AMERICANS. DNA METHYLATION (DNAM) CLOCKS ARE IMPORTANT BIOMARKERS OF CELLULAR AGING AND ARE ASSOCIATED WITH A VARIETY OF AGE-RELATED CHRONIC DISEASES AND ALL-CAUSE MORTALITY. EXAMINING THE RELATIONSHIP BETWEEN EDUCATION AND LIFESTYLE RISK FACTORS FOR AGE-RELATED DISEASES AND MULTIPLE DNAM CLOCKS CAN INCREASE THE UNDERSTANDING OF HOW RISK FACTORS CONTRIBUTE TO AGING AT THE CELLULAR LEVEL. THIS STUDY EXPLORED THE ASSOCIATION BETWEEN EDUCATION OR LIFESTYLE RISK FACTORS FOR AGE-RELATED DISEASES AND THE ACCELERATION OF FOUR DNAM CLOCKS, INCLUDING INTRINSIC (IEAA) AND EXTRINSIC EPIGENETIC AGE ACCELERATION (EEAA), PHENOAGE ACCELERATION (PHENOAA), AND GRIMAGE ACCELERATION (GRIMAA) IN THE AFRICAN AMERICAN PARTICIPANTS OF THE GENETIC EPIDEMIOLOGY NETWORK OF ARTERIOPATHY. WE PERFORMED BOTH CROSS-SECTIONAL AND LONGITUDINAL ANALYSES. IN CROSS-SECTIONAL ANALYSES, GENDER, EDUCATION, BMI, SMOKING, AND ALCOHOL CONSUMPTION WERE ALL INDEPENDENTLY ASSOCIATED WITH GRIMAA, WHEREAS ONLY SOME OF THEM WERE ASSOCIATED WITH OTHER CLOCKS. THE EFFECT OF SMOKING AND EDUCATION ON GRIMAA VARIED BY GENDER. LONGITUDINAL ANALYSES SUGGEST THAT AGE AND BMI CONTINUED TO INCREASE GRIMAA, AND THAT AGE AND CURRENT SMOKING CONTINUED TO INCREASE PHENOAA AFTER CONTROLLING DNAM CLOCKS AT BASELINE. IN CONCLUSION, EDUCATION AND COMMON LIFESTYLE RISK FACTORS WERE ASSOCIATED WITH MULTIPLE DNAM CLOCKS. HOWEVER, THE ASSOCIATION WITH EACH RISK FACTOR VARIED BY CLOCK, WHICH SUGGESTS THAT DIFFERENT CLOCKS MAY CAPTURE ADVERSE EFFECTS FROM DIFFERENT ENVIRONMENTAL STIMULI. 2019 7 3391 36 HORMETIC ASSOCIATION BETWEEN PERCEIVED STRESS AND HUMAN EPIGENETIC AGING BASED ON RESILIENCE CAPACITY. CHRONIC STRESS IS ASSOCIATED WITH DELETERIOUS HEALTH OUTCOMES AND MORTALITY RISK. A POTENTIAL MECHANISM BY WHICH STRESS AFFECTS HEALTHSPAN AND LIFESPAN IS ACCELERATION OF CELLULAR AGING. BIOLOGIC AGE PREDICTION MODELS, TERMED EPIGENETIC CLOCKS, HAVE BEEN DEVELOPED TO ESTIMATE BIOLOGIC AGE DIFFERENCES AMONG PEOPLE WITH THE SAME CHRONOLOGIC AGE. THIS STUDY EVALUATES THE SIMULTANEOUS IMPACT OF PERCEIVED CHRONIC STRESS AND RESILIENCE ON GRIM AGE ACCELERATION. THE PERCEIVED STRESS SCORE (PSS) AND CONNOR-DAVIDSON RESILIENCE SCALE (CD-RISC) WERE USED TO MEASURE CHRONIC STRESS AND RESILIENCE, RESPECTIVELY. DNA WAS EXTRACTED FROM WHOLE BLOOD AND ANALYZED USING THE METHYLATIONEPIC BEADCHIP. GRIMAGE ESTIMATES WERE CALCULATED USING THE METHYLATION AGE CALCULATOR. FORTY-SEVEN BUSINESS EXECUTIVES WERE CATEGORIZED BY LEVELS OF HIGH OR LOW STRESS AND RESILIENCE SCORES. COMPARED TO PARTICIPANTS WITH LOW STRESS AND HIGH RESILIENCE, THOSE WITH LOW STRESS AND LOW RESILIENCE DEMONSTRATED THE STRONGEST ASSOCIATION WITH GRIM AGE ACCELERATION (P = 0.044), AFTER CONTROLLING FOR AGE AND ESTIMATED CELLULAR PROPORTIONS. INTERESTINGLY, AMONG PARTICIPANTS WITH LOW RESILIENCE, THOSE WITH HIGH PERCEIVED STRESS HAD A WEAKER ASSOCIATION WITH GRIM AGE ACCELERATION THAN PARTICIPANTS WITH LOW PERCEIVED STRESS. HOWEVER, AMONG PARTICIPANTS WITH HIGH RESILIENCE, LOW PERCEIVED STRESS HAD A WEAKER ASSOCIATION WITH GRIM AGE ACCELERATION THAN HIGH PERCEIVED STRESS. OUR FINDINGS SUGGEST THAT THE IMPACT OF PERCEIVED STRESS ON EPIGENETIC AGE ACCELERATION MAY DIFFER BASED ON RESILIENCE CAPACITY, WITH A POTENTIAL PARADOXICAL BENEFICIAL EFFECT AMONG THOSE WITH LOW RESILIENCE. 2022 8 1776 39 ECONOMIC HARDSHIP AND BIOLOGICAL WEATHERING: THE EPIGENETICS OF AGING IN A U.S. SAMPLE OF BLACK WOMEN. BACKGROUND: PAST RESEARCH HAS LINKED LOW SOCIO-ECONOMIC STATUS (SES) TO INFLAMMATION, METABOLIC DYSREGULATION, AND VARIOUS CHRONIC AND AGE-RELATED DISEASES SUCH AS TYPE 2 DIABETES, CORONARY HEART DISEASE, STROKE, AND DEMENTIA. THESE STUDIES SUGGEST THAT THE CHALLENGES AND ADVERSITIES ASSOCIATED WITH LOW SES MAY RESULT IN PREMATURE AGING AND INCREASED RISK OF MORBIDITY AND MORTALITY. OBJECTIVE: BUILDING UPON THIS RESEARCH, THE PRESENT STUDY INVESTIGATES VARIOUS AVENUES WHEREBY LOW INCOME MIGHT ACCELERATE BIOLOGICAL AGING. METHODS: STRUCTURAL EQUATION MODELING AND LONGITUDINAL DATA FROM A SAMPLE OF 100 BLACK, MIDDLE-AGED WOMEN RESIDING IN THE UNITED STATES WAS USED TO INVESTIGATE THE EFFECT OF INCOME ON A RECENTLY DEVELOPED EPIGENETIC MEASURE OF BIOLOGICAL AGING. THIS MEASURE CAN BE USED AS A "BIOLOGICAL CLOCK" TO ASSESS, AT ANY POINT DURING ADULTHOOD, THE EXTENT TO WHICH AN INDIVIDUAL IS EXPERIENCING ACCELERATED OR DECELERATED BIOLOGICAL AGING. RESULTS: LOW INCOME DISPLAYED A ROBUST ASSOCIATION WITH ACCELERATED AGING THAT WAS UNAFFECTED AFTER CONTROLLING FOR OTHER SES-RELATED FACTORS SUCH AS EDUCATION, MARITAL STATUS, AND CHILDHOOD ADVERSITY. FURTHER, OUR ANALYSES INDICATED THAT THE ASSOCIATION BETWEEN INCOME AND BIOLOGICAL AGING WAS NOT EXPLAINED BY HEALTH-RELATED BEHAVIORS SUCH AS DIET, EXERCISE, SMOKING, ALCOHOL CONSUMPTION, OR HAVING HEALTH INSURANCE. RATHER, IN LARGE MEASURE, IT WAS FINANCIAL PRESSURE (DIFFICULTY PAYING BILLS, BUYING NECESSITIES, OR MEETING DAILY EXPENSES) THAT ACCOUNTED FOR THE ASSOCIATION BETWEEN LOW INCOME AND ACCELERATED AGING. CONCLUSIONS: THESE FINDINGS SUPPORT THE VIEW THAT CHRONIC FINANCIAL PRESSURES ASSOCIATED WITH LOW INCOME EXERT A WEATHERING EFFECT THAT RESULTS IN PREMATURE AGING. 2016 9 5748 39 SOCIAL AND PHYSICAL ENVIRONMENTS EARLY IN DEVELOPMENT PREDICT DNA METHYLATION OF INFLAMMATORY GENES IN YOUNG ADULTHOOD. CHRONIC INFLAMMATION CONTRIBUTES TO A WIDE RANGE OF HUMAN DISEASES, AND ENVIRONMENTS IN INFANCY AND CHILDHOOD ARE IMPORTANT DETERMINANTS OF INFLAMMATORY PHENOTYPES. THE UNDERLYING BIOLOGICAL MECHANISMS CONNECTING EARLY ENVIRONMENTS WITH THE REGULATION OF INFLAMMATION IN ADULTHOOD ARE NOT KNOWN, BUT EPIGENETIC PROCESSES ARE PLAUSIBLE CANDIDATES. WE TESTED THE HYPOTHESIS THAT PATTERNS OF DNA METHYLATION (DNAM) IN INFLAMMATORY GENES IN YOUNG ADULTHOOD WOULD BE PREDICTED BY EARLY LIFE NUTRITIONAL, MICROBIAL, AND PSYCHOSOCIAL EXPOSURES PREVIOUSLY ASSOCIATED WITH LEVELS OF INFLAMMATION. DATA COME FROM A POPULATION-BASED LONGITUDINAL BIRTH COHORT STUDY IN METROPOLITAN CEBU, THE PHILIPPINES, AND DNAM WAS CHARACTERIZED IN WHOLE BLOOD SAMPLES FROM 494 PARTICIPANTS (AGE 20-22 Y). ANALYSES FOCUSED ON PROBES IN 114 TARGET GENES INVOLVED IN THE REGULATION OF INFLAMMATION, AND WE IDENTIFIED 10 SITES ACROSS NINE GENES WHERE THE LEVEL OF DNAM WAS SIGNIFICANTLY PREDICTED BY THE FOLLOWING VARIABLES: HOUSEHOLD SOCIOECONOMIC STATUS IN CHILDHOOD, EXTENDED ABSENCE OF A PARENT IN CHILDHOOD, EXPOSURE TO ANIMAL FECES IN INFANCY, BIRTH IN THE DRY SEASON, OR DURATION OF EXCLUSIVE BREASTFEEDING. TO EVALUATE THE BIOLOGICAL SIGNIFICANCE OF THESE SITES, WE TESTED FOR ASSOCIATIONS WITH A PANEL OF INFLAMMATORY BIOMARKERS MEASURED IN PLASMA OBTAINED AT THE SAME AGE AS DNAM ASSESSMENT. THREE SITES PREDICTED ELEVATED INFLAMMATION, AND ONE SITE PREDICTED LOWER INFLAMMATION, CONSISTENT WITH THE INTERPRETATION THAT LEVELS OF DNAM AT THESE SITES ARE FUNCTIONALLY RELEVANT. THIS PATTERN OF RESULTS POINTS TOWARD DNAM AS A POTENTIALLY IMPORTANT BIOLOGICAL MECHANISM THROUGH WHICH DEVELOPMENTAL ENVIRONMENTS SHAPE INFLAMMATORY PHENOTYPES ACROSS THE LIFE COURSE. 2017 10 1960 33 EPIGENETIC AGING IN CHILDREN FROM A SMALL-SCALE FARMING SOCIETY IN THE CONGO BASIN: ASSOCIATIONS WITH CHILD GROWTH AND FAMILY CONFLICT. DEVELOPMENTAL ENVIRONMENTS INFLUENCE INDIVIDUALS' LONG-TERM HEALTH TRAJECTORIES, AND THERE IS INCREASING EMPHASIS ON UNDERSTANDING THE BIOLOGICAL PATHWAYS THROUGH WHICH THIS OCCURS. EPIGENETIC AGING EVALUATES DNA METHYLATION AT A SUITE OF DISTINCT CPG SITES IN THE GENOME, AND EPIGENETIC AGE ACCELERATION (EAA) IS LINKED TO HEIGHTENED CHRONIC MORBIDITY AND MORTALITY RISKS IN ADULTS. CONSEQUENTLY, EAA PROVIDES INSIGHTS ON TRAJECTORIES OF BIOLOGICAL AGING, WHICH EARLY LIFE EXPERIENCES MAY HELP SHAPE. HOWEVER, FEW STUDIES HAVE MEASURED CORRELATES OF CHILDREN'S EPIGENETIC AGING, ESPECIALLY OUTSIDE OF THE U.S. AND EUROPE. IN PARTICULAR, LITTLE IS KNOWN ABOUT HOW CHILDREN'S GROWTH AND DEVELOPMENT RELATE TO EAA IN ECOLOGIES IN WHICH ENERGETIC AND PATHOGENIC STRESSORS ARE COMMONPLACE. WE STUDIED EAA FROM DRIED BLOOD SPOTS AMONG BONDONGO CHILDREN (N = 54) RESIDING IN A SMALL-SCALE, FISHER-FARMER SOCIETY IN A REMOTE REGION OF THE REPUBLIC OF THE CONGO. HERE, INFECTIOUS DISEASE BURDENS AND THEIR RESULTANT ENERGY DEMANDS ARE HIGH. CHILDREN WHO WERE HEAVIER FOR HEIGHT OR TALLER FOR AGE, RESPECTIVELY, EXHIBITED GREATER EAA, INCLUDING INTRINSIC EAA, WHICH IS CONSIDERED TO MEASURE EAA INTERNAL TO CELLS. FURTHERMORE, WE FOUND THAT CHILDREN IN FAMILIES WITH MORE CONFLICT BETWEEN PARENTS HAD GREATER INTRINSIC EAA. THESE RESULTS SUGGEST THAT IN CONTEXTS IN WHICH LIMITED ENERGY MUST BE ALLOCATED TO COMPETING DEMANDS, MORE INVESTMENT IN GROWTH MAY COINCIDE WITH GREATER EAA, WHICH PARALLELS FINDINGS IN EUROPEAN CHILDREN WHO DO NOT FACE SIMILAR ENERGETIC CONSTRAINTS. OUR FINDINGS ALSO INDICATE THAT ASSOCIATIONS BETWEEN ADVERSE FAMILY ENVIRONMENTS AND GREATER INTRINSIC EAA WERE NONETHELESS OBSERVABLE BUT ONLY AFTER ADJUSTMENT FOR COVARIATES RELEVANT TO THE ENERGETICALLY AND IMMUNOLOGICALLY DEMANDING NATURE OF THE LOCAL ECOLOGY. 2020 11 2677 30 EVALUATING THE CHALLENGES AND REPRODUCIBILITY OF STUDIES INVESTIGATING DNA METHYLATION SIGNATURES OF PSYCHOLOGICAL STRESS. PSYCHOLOGICAL STRESS CAN INCREASE THE RISK OF A WIDE RANGE OF NEGATIVE HEALTH OUTCOMES. STUDIES HAVE BEEN COMPLETED TO DETERMINE IF DNA METHYLATION CHANGES OCCUR IN THE HUMAN BRAIN BECAUSE OF STRESS AND ARE ASSOCIATED WITH LONG-TERM EFFECTS AND DISEASE, BUT RESULTS HAVE BEEN INCONSISTENT. HUMAN CANDIDATE GENE STUDIES (150) AND EPIGENOME-WIDE ASSOCIATION STUDIES (67) WERE SYSTEMATICALLY EVALUATED TO ASSESS HOW DNA METHYLATION IS IMPACTED BY STRESS DURING THE PRENATAL PERIOD, EARLY CHILDHOOD AND ADULTHOOD. THE ASSOCIATION BETWEEN DNA METHYLATION OF NR3C1 EXON 1F AND CHILD MALTREATMENT AND EARLY LIFE ADVERSITY WAS WELL DEMONSTRATED, BUT OTHER GENES DID NOT EXHIBIT A CLEAR ASSOCIATION. THE REPRODUCIBILITY OF INDIVIDUAL CPG SITES IN EPIGENOME-WIDE ASSOCIATION STUDIES WAS ALSO POOR. HOWEVER, BIOLOGICAL PATHWAYS, INCLUDING STRESS RESPONSE, BRAIN DEVELOPMENT AND IMMUNITY, HAVE BEEN CONSISTENTLY IDENTIFIED ACROSS DIFFERENT STRESSORS THROUGHOUT THE LIFE SPAN. FUTURE STUDIES WOULD BENEFIT FROM THE INCREASED SAMPLE SIZE, LONGITUDINAL DESIGN, STANDARDIZED METHODOLOGY, OPTIMAL QUALITY CONTROL, AND IMPROVED STATISTICAL PROCEDURES. 2022 12 2047 29 EPIGENETIC CLOCKS MAY COME OUT OF RHYTHM-IMPLICATIONS FOR THE ESTIMATION OF CHRONOLOGICAL AGE IN FORENSIC CASEWORK. THERE IS A GROWING PERCEPTION THAT DNA METHYLATION MAY BE INFLUENCED BY EXOGENOUS AND ENDOGENOUS PARAMETERS. KNOWLEDGE OF THESE FACTORS IS OF GREAT RELEVANCE FOR THE INTERPRETATION OF DNA-METHYLATION DATA FOR THE ESTIMATION OF CHRONOLOGICAL AGE IN FORENSIC CASEWORK. WE PERFORMED A LITERATURE REVIEW TO IDENTIFY PARAMETERS, WHICH MIGHT BE OF RELEVANCE FOR THE PREDICTION OF CHRONOLOGICAL AGE BASED ON DNA METHYLATION. THE QUALITY OF AGE PREDICTIONS MIGHT PARTICULARLY BE INFLUENCED BY LIFETIME ADVERSITIES (CHRONIC STRESS, TRAUMA/POST-TRAUMATIC STRESS DISORDER (PTSD), VIOLENCE, LOW SOCIOECONOMIC STATUS/EDUCATION), CANCER, OBESITY AND RELATED DISEASES, INFECTIOUS DISEASES (ESPECIALLY HIV AND CYTOMEGALOVIRUS (CMV) INFECTIONS), SEX, ETHNICITY AND EXPOSURE TO TOXINS (ALCOHOL, SMOKING, AIR POLLUTION, PESTICIDES). SUCH FACTORS MAY ALTER THE DNA METHYLATION PATTERN AND MAY EXPLAIN THE PARTLY HIGH DEVIATIONS BETWEEN EPIGENETIC AGE AND CHRONOLOGICAL AGE IN SINGLE CASES (DESPITE OF LOW MEAN ABSOLUTE DEVIATIONS) THAT CAN ALSO BE OBSERVED WITH "EPIGENETIC CLOCKS" COMPRISING A HIGH NUMBER OF CPG SITES. SO FAR, ONLY FEW PUBLICATIONS DEALING WITH FORENSIC AGE ESTIMATION ADDRESS THESE CONFOUNDING FACTORS. FUTURE RESEARCH SHOULD FOCUS ON THE IDENTIFICATION OF FURTHER RELEVANT CONFOUNDING FACTORS AND THE DEVELOPMENT OF MODELS THAT ARE "ROBUST" AGAINST THE INFLUENCE OF SUCH BIOLOGICAL FACTORS BY SYSTEMATIC INVESTIGATIONS UNDER TARGETED INCLUSION OF DIVERSE AND DEFINED COHORTS. 2020 13 6112 35 THE EPIGENETIC CLOCK AS A PREDICTOR OF DISEASE AND MORTALITY RISK: A SYSTEMATIC REVIEW AND META-ANALYSIS. BACKGROUND: AGEING IS ONE OF THE PRINCIPAL RISK FACTORS FOR MANY CHRONIC DISEASES. HOWEVER, THERE IS CONSIDERABLE BETWEEN-PERSON VARIATION IN THE RATE OF AGEING AND INDIVIDUAL DIFFERENCES IN THEIR SUSCEPTIBILITY TO DISEASE AND DEATH. EPIGENETIC MECHANISMS MAY PLAY A ROLE IN HUMAN AGEING, AND DNA METHYLATION AGE BIOMARKERS MAY BE GOOD PREDICTORS OF AGE-RELATED DISEASES AND MORTALITY RISK. THE AIMS OF THIS SYSTEMATIC REVIEW WERE TO IDENTIFY AND SYNTHESISE THE EVIDENCE FOR AN ASSOCIATION BETWEEN PERIPHERALLY MEASURED DNA METHYLATION AGE AND LONGEVITY, AGE-RELATED DISEASE, AND MORTALITY RISK. METHODS: A SYSTEMATIC SEARCH WAS CONDUCTED IN LINE WITH THE PREFERRED REPORTING ITEMS FOR SYSTEMATIC REVIEWS AND META-ANALYSES (PRISMA) GUIDELINES. USING RELEVANT SEARCH TERMS, MEDLINE, EMBASE, COCHRANE CENTRAL REGISTER OF CONTROLLED TRIALS, AND PSYCHINFO DATABASES WERE SEARCHED TO IDENTIFY ARTICLES MEETING THE INCLUSION CRITERIA. STUDIES WERE ASSESSED FOR BIAS USING JOANNA BRIGGS INSTITUTE CRITICAL APPRAISAL CHECKLISTS. DATA WAS EXTRACTED FROM STUDIES MEASURING AGE ACCELERATION AS A PREDICTOR OF AGE-RELATED DISEASES, MORTALITY OR LONGEVITY, AND THE FINDINGS FOR SIMILAR OUTCOMES COMPARED. USING REVIEW MANAGER 5.3 SOFTWARE, TWO META-ANALYSES (ONE PER EPIGENETIC CLOCK) WERE CONDUCTED ON STUDIES MEASURING ALL-CAUSE MORTALITY. RESULTS: TWENTY-THREE RELEVANT ARTICLES WERE IDENTIFIED, INCLUDING A TOTAL OF 41,607 PARTICIPANTS. FOUR STUDIES FOCUSED ON AGEING AND LONGEVITY, 11 ON AGE-RELATED DISEASE (CANCER, CARDIOVASCULAR DISEASE, AND DEMENTIA), AND 11 ON MORTALITY. THERE WAS SOME, ALTHOUGH INCONSISTENT, EVIDENCE FOR AN ASSOCIATION BETWEEN INCREASED DNA METHYLATION AGE AND RISK OF DISEASE. META-ANALYSES INDICATED THAT EACH 5-YEAR INCREASE IN DNA METHYLATION AGE WAS ASSOCIATED AN 8 TO 15% INCREASED RISK OF MORTALITY. CONCLUSION: DUE TO THE SMALL NUMBER OF STUDIES AND HETEROGENEITY IN STUDY DESIGN AND OUTCOMES, THE ASSOCIATION BETWEEN DNA METHYLATION AGE AND AGE-RELATED DISEASE AND LONGEVITY IS INCONCLUSIVE. INCREASED EPIGENETIC AGE WAS ASSOCIATED WITH MORTALITY RISK, BUT POSITIVE PUBLICATION BIAS NEEDS TO BE CONSIDERED. FURTHER RESEARCH IS NEEDED TO DETERMINE THE EXTENT TO WHICH DNA METHYLATION AGE CAN BE USED AS A CLINICAL BIOMARKER. 2019 14 5957 32 TELOMERE LENGTH AND EPIGENETIC AGE ACCELERATION IN ADOLESCENTS WITH ANXIETY DISORDERS. EVIDENCE ON THE RELATIONSHIP BETWEEN GENETICS AND MENTAL HEALTH ARE FLOURISHING. HOWEVER, FEW STUDIES ARE EVALUATING EARLY BIOMARKERS THAT MIGHT LINK GENES, ENVIRONMENT, AND PSYCHOPATHOLOGY. WE AIMED TO STUDY TELOMERE LENGTH (TL) AND EPIGENETIC AGE ACCELERATION (AA) IN A COHORT OF ADOLESCENTS WITH AND WITHOUT ANXIETY DISORDERS (N = 234). WE EVALUATED A REPRESENTATIVE SUBSAMPLE OF PARTICIPANTS AT BASELINE AND AFTER 5 YEARS (N = 76) AND CATEGORIZED THEM ACCORDING TO THEIR ANXIETY DISORDER DIAGNOSIS AT BOTH TIME POINTS: (1) CONTROL GROUP (NO ANXIETY DISORDER, N = 18), (2) VARIABLE GROUP (ANXIETY DISORDER IN ONE EVALUATION, N = 38), AND (3) PERSISTENT GROUP (ANXIETY DISORDER AT BOTH TIME POINTS, N = 20). WE ASSESSED RELATIVE MEAN TL BY REAL-TIME QUANTITATIVE PCR AND DNA METHYLATION BY INFINIUM HUMANMETHYLATION450 BEADCHIP. WE CALCULATED AA USING THE HORVATH AGE ESTIMATION ALGORITHM AND ANALYZED DIFFERENCES AMONG GROUPS USING GENERALIZED LINEAR MIXED MODELS. THE PERSISTENT GROUP OF ANXIETY DISORDER DID NOT CHANGE TL OVER TIME (P = 0.495). THE VARIABLE GROUP HAD HIGHER BASELINE TL (P = 0.003) BUT NO ACCELERATED TL EROSION IN COMPARISON TO THE NON-ANXIETY CONTROL GROUP (P = 0.053). FURTHERMORE, THERE WERE NO DIFFERENCES IN AA AMONG GROUPS OVER TIME. OUR FINDINGS SUGGEST THAT ADOLESCENTS WITH CHRONIC ANXIETY DID NOT CHANGE TELOMERE LENGTH OVER TIME, WHICH COULD BE RELATED TO A DELAY IN NEURONAL DEVELOPMENT IN THIS PERIOD OF LIFE. 2021 15 173 36 ACCELERATED AGING IN BIPOLAR DISORDERS: AN EXPLORATORY STUDY OF SIX EPIGENETIC CLOCKS. BIPOLAR DISORDER (BD) IS A CHRONIC AND SEVERE PSYCHIATRIC DISORDER ASSOCIATED WITH SIGNIFICANT MEDICAL MORBIDITY AND REDUCED LIFE EXPECTANCY. IN THIS STUDY, WE ASSESSED ACCELERATED EPIGENETIC AGING IN INDIVIDUALS WITH BD USING VARIOUS DNA METHYLATION (DNAM)-BASED MARKERS. FOR THIS PURPOSE, WE USED FIVE EPIGENETIC CLOCKS (HORVATH, HANNUM, EN, PHENOAGE, AND GRIMAGE) AND A DNAM-BASED TELOMERE LENGTH CLOCK (DNAMTL). DNAM PROFILES WERE OBTAINED USING INFINIUM METHYLATIONEPIC ARRAYS FROM WHOLE-BLOOD SAMPLES OF 184 INDIVIDUALS WITH BD. WE ALSO ESTIMATED BLOOD CELL COUNTS BASED ON DNAM LEVELS FOR ADJUSTMENT. SIGNIFICANT CORRELATIONS BETWEEN CHRONOLOGICAL AGE AND EACH EPIGENETIC AGE ESTIMATED USING THE SIX DIFFERENT CLOCKS WERE OBSERVED. FOLLOWING ADJUSTMENT FOR BLOOD CELL COUNTS, WE FOUND THAT THE SIX EPIGENETIC AGEACCELS (AGE ACCELERATIONS) WERE SIGNIFICANTLY ASSOCIATED WITH THE BODY MASS INDEX. GRIMAGE AGEACCEL WAS SIGNIFICANTLY ASSOCIATED WITH MALE SEX, SMOKING STATUS AND CHILDHOOD MALTREATMENT. DNAMTL AGEACCEL WAS SIGNIFICANTLY ASSOCIATED WITH SMOKING STATUS. OVERALL, THIS STUDY SHOWED THAT DISTINCT EPIGENETIC CLOCKS ARE SENSITIVE TO DIFFERENT ASPECTS OF AGING PROCESS IN BD. FURTHER INVESTIGATIONS WITH COMPREHENSIVE EPIGENETIC CLOCK ANALYSES AND LARGE SAMPLES ARE REQUIRED TO CONFIRM OUR FINDINGS OF POTENTIAL DETERMINANTS OF AN ACCELERATED EPIGENETIC AGING IN BD. 2023 16 5884 28 SYSTEMIC INFLAMMATION AND BIOLOGICAL AGING IN THE HEALTH AND RETIREMENT STUDY. CHRONIC, LOW-LEVEL SYSTEMIC INFLAMMATION ASSOCIATED WITH AGING, OR INFLAMMAGING, IS A RISK FACTOR FOR SEVERAL CHRONIC DISEASES AND MORTALITY. USING DATA FROM THE HEALTH AND RETIREMENT STUDY, WE GENERATED A CONTINUOUS LATENT VARIABLE FOR SYSTEMIC INFLAMMATION FROM SEVEN MEASURED INDICATORS OF INFLAMMATION AND EXAMINED ASSOCIATIONS WITH ANOTHER BIOMARKER OF BIOLOGICAL AGING, DNA METHYLATION AGE ACCELERATION MEASURED BY EPIGENETIC CLOCKS, AND 4-YEAR MORTALITY (N = 3,113). WE FOUND THAT GREATER SYSTEMIC INFLAMMATION WAS POSITIVELY ASSOCIATED WITH DNA METHYLATION AGE ACCELERATION FOR 10 OF THE 13 EPIGENETIC CLOCKS, AFTER ADJUSTMENT FOR SOCIODEMOGRAPHICS AND CHRONIC DISEASE RISK FACTORS. THE LATENT VARIABLE FOR SYSTEMIC INFLAMMATION WAS ASSOCIATED WITH 4-YEAR MORTALITY INDEPENDENT OF DNA METHYLATION AGE ACCELERATION AND WAS A BETTER PREDICTOR OF 4-YEAR MORTALITY THAN ANY OF THE EPIGENETIC CLOCKS EXAMINED, AS WELL AS MORTALITY RISK FACTORS, INCLUDING OBESITY AND MULTIMORBIDITY. INFLAMMAGING AND DNA METHYLATION AGE ACCELERATION MAY REPRESENT DIFFERENT BIOLOGICAL PROCESSES CONTRIBUTING TO MORTALITY RISK. LEVERAGING MULTIPLE MEASURED INFLAMMATION MARKERS TO CAPTURE INFLAMMAGING IS IMPORTANT FOR BIOLOGY OF AGING RESEARCH. 2023 17 649 29 BIRTHWEIGHT, MATERNAL WEIGHT TRAJECTORIES AND GLOBAL DNA METHYLATION OF LINE-1 REPETITIVE ELEMENTS. LOW BIRTHWEIGHT, PREMATURE BIRTH, INTRAUTERINE GROWTH RETARDATION, AND MATERNAL MALNUTRITION HAVE BEEN RELATED TO AN INCREASED RISK OF CARDIOVASCULAR DISEASE, TYPE 2 DIABETES MELLITUS, OBESITY, AND NEUROPSYCHIATRIC DISORDERS LATER IN LIFE. CONVERSELY, HIGH BIRTHWEIGHT HAS BEEN LINKED TO FUTURE RISK OF CANCER. GLOBAL DNA METHYLATION ESTIMATED BY THE METHYLATION OF REPETITIVE SEQUENCES IN THE GENOME IS AN INDICATOR OF SUSCEPTIBILITY TO CHRONIC DISEASES. WE USED DATA AND BIOSPECIMENS FROM AN EPIGENETIC BIRTH COHORT TO EXPLORE THE ASSOCIATION BETWEEN TRAJECTORIES OF FETAL AND MATERNAL WEIGHT AND LINE-1 METHYLATION IN 319 MOTHER-CHILD DYADS. NEWBORNS WITH LOW OR HIGH BIRTHWEIGHT HAD SIGNIFICANTLY LOWER LINE-1 METHYLATION LEVELS IN THEIR CORD BLOOD COMPARED TO NORMAL WEIGHT INFANTS AFTER ADJUSTING FOR GESTATIONAL AGE, SEX OF THE CHILD, MATERNAL AGE AT DELIVERY, AND MATERNAL SMOKING DURING PREGNANCY (P = 0.007 AND P = 0.036, RESPECTIVELY), BUT THE MAGNITUDE OF THE DIFFERENCE WAS SMALL. INFANTS BORN PREMATURELY ALSO HAD LOWER LINE-1 METHYLATION LEVELS IN CORD BLOOD COMPARED TO TERM INFANTS, AND THIS DIFFERENCE, THOUGH SMALL, WAS STATISTICALLY SIGNIFICANT (P = 0.004). WE DID NOT FIND IMPORTANT ASSOCIATIONS BETWEEN MATERNAL PREPREGNANCY BMI OR GESTATIONAL WEIGHT GAIN AND GLOBAL METHYLATION OF THE CORD BLOOD OR FETAL PLACENTAL TISSUE. IN CONCLUSION, WE FOUND SIGNIFICANT DIFFERENCES IN CORD BLOOD LINE-1 METHYLATION AMONG NEWBORNS WITH LOW AND HIGH BIRTHWEIGHT AS WELL AS AMONG PREMATURELY BORN INFANTS. FUTURE STUDIES MAY ELUCIDATE WHETHER CHROMOSOMAL INSTABILITIES OR OTHER FUNCTIONAL CONSEQUENCES OF THESE CHANGES CONTRIBUTE TO THE INCREASED RISK OF CHRONIC DISEASES AMONG INDIVIDUALS WITH THESE CHARACTERISTICS. 2011 18 5747 27 SOCIAL ADVERSITY AND EPIGENETIC AGING: A MULTI-COHORT STUDY ON SOCIOECONOMIC DIFFERENCES IN PERIPHERAL BLOOD DNA METHYLATION. LOW SOCIOECONOMIC STATUS (SES) IS ASSOCIATED WITH EARLIER ONSET OF AGE-RELATED CHRONIC CONDITIONS AND REDUCED LIFE-EXPECTANCY, BUT THE UNDERLYING BIOMOLECULAR MECHANISMS REMAIN UNCLEAR. EVIDENCE OF DNA-METHYLATION DIFFERENCES BY SES SUGGESTS A POSSIBLE ASSOCIATION OF SES WITH EPIGENETIC AGE ACCELERATION (AA). WE INVESTIGATED THE ASSOCIATION OF SES WITH AA IN MORE THAN 5,000 INDIVIDUALS BELONGING TO THREE INDEPENDENT PROSPECTIVE COHORTS FROM ITALY, AUSTRALIA, AND IRELAND. LOW SES WAS ASSOCIATED WITH GREATER AA (BETA = 0.99 YEARS; 95% CI 0.39,1.59; P = 0.002; COMPARING EXTREME CATEGORIES). THE RESULTS WERE CONSISTENT ACROSS DIFFERENT SES INDICATORS. THE ASSOCIATIONS WERE ONLY PARTIALLY MODULATED BY THE UNHEALTHY LIFESTYLE HABITS OF INDIVIDUALS WITH LOWER SES. INDIVIDUALS WHO EXPERIENCED LIFE-COURSE SES IMPROVEMENT HAD INTERMEDIATE AA COMPARED TO EXTREME SES CATEGORIES, SUGGESTING REVERSIBILITY OF THE EFFECT AND SUPPORTING THE RELATIVE IMPORTANCE OF THE EARLY CHILDHOOD SOCIAL ENVIRONMENT. SOCIOECONOMIC ADVERSITY IS ASSOCIATED WITH ACCELERATED EPIGENETIC AGING, IMPLICATING BIOMOLECULAR MECHANISMS THAT MAY LINK SES TO AGE-RELATED DISEASES AND LONGEVITY. 2017 19 1772 37 EARLY-LIFE SOCIOECONOMIC DISADVANTAGE, NOT CURRENT, PREDICTS ACCELERATED EPIGENETIC AGING OF MONOCYTES. LOW SOCIOECONOMIC STATUS (SES) IN EARLY-LIFE AND ADULTHOOD INDEPENDENTLY CONTRIBUTE TO INCREASED RISK FOR AGING-RELATED CHRONIC DISEASES. ONE MECHANISTIC HYPOTHESIS FOR THESE ASSOCIATIONS INVOLVES FASTER CELLULAR AGING OF IMMUNE CELLS, WHICH COULD PLAUSIBLY CONTRIBUTE TO CHRONIC DISEASE PATHOGENESIS BY COMPROMISING HOST RESISTANCE AND/OR UP-REGULATING INFLAMMATION. HOWEVER, LITTLE IS KNOWN ABOUT THE ASSOCIATION BETWEEN LIFE-COURSE SES AND CELLULAR AGING. THE PRESENT STUDY EXAMINES THE ASSOCIATION OF EARLY-LIFE AND CURRENT SES WITH A NOVEL BIOMARKER OF CELLULAR AGING TERMED THE "EPIGENETIC CLOCK," IN MONOCYTES. ADDITIONALLY, WE EXAMINE HEALTH BEHAVIORS AND DEPRESSIVE SYMPTOMS AS POTENTIAL EXPLANATORY PATHWAYS. THE STUDY INVOLVED 335 PARTICIPANTS BETWEEN THE AGES OF 15 AND 55 FROM VANCOUVER, CANADA AND SURROUNDING AREAS. ENROLLED PARTICIPANTS HAD TO FIT INTO FOUR LIFE-COURSE SES TRAJECTORIES, CORRESPONDING TO LOW-LOW, LOW-HIGH, HIGH-LOW AND HIGH-HIGH COMBINATIONS OF EARLY-LIFE (AGES 0 TO 5) AND CURRENT SES RESPECTIVELY. CELLULAR AGING OF MONOCYTES WAS MEASURED USING HORVATH'S DNA METHYLATION DERIVED MEASURE OF EPIGENETIC AGE ACCELERATION. RESULTS INDICATED THAT SOCIOECONOMIC DISADVANTAGE DURING EARLY-LIFE, BUT NOT LATER IN LIFE, WAS ASSOCIATED WITH ACCELERATED EPIGENETIC AGING OF MONOCYTES. NO EARLY-LIFE SES BY CURRENT SES INTERACTION WAS DETECTED, SUGGESTING THAT SOCIOECONOMIC MOBILITY IS UNRELATED TO EPIGENETIC AGE ACCELERATION. IN PATH ANALYSES, NEITHER CURRENT HEALTH BEHAVIORS NOR CURRENT DEPRESSIVE SYMPTOMS EMERGED AS MEDIATORS OF THE EARLY-LIFE SES EFFECT. THESE FINDINGS SUGGEST SOCIOECONOMIC DISADVANTAGE IN EARLY-LIFE IS INDEPENDENTLY PREDICTIVE OF CELLULAR AGING OF IMMUNE CELLS, WITH POTENTIAL IMPLICATIONS FOR AGING-RELATED DISEASES LATER IN LIFE. 2018 20 1516 34 DNA METHYLATION AS A BIOMARKER OF AGING IN EPIDEMIOLOGIC STUDIES. CANCER IS LARGELY AN AGING DISEASE. ACCELERATED BIOLOGICAL AGING MAY BE THE STRONGEST PREDICTOR OF CANCER AND OTHER CHRONIC DISEASE RISKS. IN THE ABSENCE OF RELIABLE AND QUANTIFIABLE BIOMARKERS OF AGING TO DATE, IT HAS LONG BEEN OBSERVED THAT TUMORIGENESIS SHARES DISTINCT EPIGENETIC ALTERATIONS WITH THE AGING PROCESS. RECENTLY, EPIGENETIC AGE ESTIMATES HAVE BEEN DEVELOPED BASED ON THE AVAILABILITY OF GENOME-WIDE DNA METHYLATION PROFILES, BY APPLYING IN THE PREDICTION FORMULA THE METHYLATION LEVEL AT A SUBSET OF HIGHLY PREDICTIVE METHYLATION SITES, CALLED EPIGENETIC CLOCK. THESE DNA METHYLATION AGE ESTIMATES HAVE PRODUCED REMARKABLY STRONG CORRELATIONS WITH CHRONOLOGICAL AGE, WITH A SMALL DEVIATION AND HIGH REPRODUCIBILITY ACROSS DIFFERENT AGE GROUPS AND STUDY POPULATIONS. MOREOVER, AN INCREASING NUMBER OF EPIDEMIOLOGIC STUDIES HAVE DEMONSTRATED AN INDEPENDENT ASSOCIATION OF DNA METHYLATION AGE OR THE EXTENT OF ACCELERATION WITH MORTALITY AND VARIOUS AGING-RELATED CONDITIONS, EVEN AFTER ACCOUNTING FOR DIFFERENCES IN CHRONOLOGICAL AGE AND OTHER RISK FACTORS. ALTHOUGH EPIGENETIC PROFILES ARE KNOWN TO BE TISSUE-SPECIFIC, BOTH TARGET TISSUE- AND MULTIPLE TISSUE-DERIVED ESTIMATES APPEAR TO PERFORM WELL TO CAPTURE WHAT IS THOUGHT TO BE THE CUMULATIVE EPIGENETIC DRIFT THAT REPRESENTS A MULTIFACTORIAL DEGENERATIVE PROCESS ACROSS TISSUES AND ORGANISMS. FURTHER REFINEMENT OF THE EPIGENETIC AGE ESTIMATES IS ANTICIPATED OVER TIME TO ACCOMMODATE A BETTER TECHNOLOGICAL COVERAGE OF THE METHYLOME AND A BETTER UNDERSTANDING OF THE BIOLOGY UNDERLYING PREDICTIVE REGIONS. EPIDEMIOLOGIC PRINCIPLES WILL REMAIN CRITICAL FOR THE EVALUATION OF RESEARCH FINDINGS INVOLVING, FOR EXAMPLE, DIFFERENT STUDY POPULATIONS, DESIGN, FOLLOW-UP TIME, AND QUALITY OF COVARIATE DATA. OVERALL, THE EPIGENETIC AGE ESTIMATES ARE AN EXCITING DEVELOPMENT WITH USEFUL IMPLICATIONS FOR BIOMEDICAL RESEARCH OF HEALTHY AGING AND DISEASE PREVENTION AND CONTROL. 2018