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Background. The purpose of the present study was to examine, first, whether hearing acuity predicts falls and whether the potential association is explained by postural balance and, second, to examine whether shared genetic or environmental effects underlie these associations. Methods. Hearing was measured using a clinical audiometer as a part of the Finnish Twin Study on Aging in 103 monozygotic and 114 dizygotic female twin pairs aged 63-76 years. Postural balance was indicated as a center of pressure (COP) movement in semitandem stance, and participants filled in a fall-calendar daily for an average of 345 days after the baseline. Results. Mean hearing acuity (better ear hearing threshold level at 0.5-4 kHz) was 21 dB (standard deviation [SDI 12). Means of the COP velocity moment for the best to the poorest hearing quartiles increased linearly from 40.7 mm²/s (SD 24.4) to 52.8 mm2/s (SD 32.0) (p value for the trend = .003). Altogether 199 participants reported 437 falls. Age-adjusted incidence rate ratios (IRR5) for falls, with the best hearing quartile as a reference, were 1.2 (95% confidence interval [CI] = 0.4-3.8) in the second, 4.1(95% Cl = 1.1-15.6) in the third, and 3.4 (95% Cl = 1.0-11.4) in the poorest hearing quartiles. Adjustment for COP velocity moment decreased IRRs markedly. Twin analyses showed that the association between hearing acuity and postural balance was not explained by genetic factors in common for these traits. Conclusion. People with poor hearing acuity have a higher risk for falls, which is partially explained by their poorer postural control. Auditory information about environment may be important for safe mobility. [ABSTRACT FROM AUTHOR]

Background We used a polygenic score for hand grip strength (PGS HGS) to investigate whether genetic predisposition for higher muscle strength predicts age-related noncommunicable diseases, survival from acute adverse health events, and mortality. Methods This study consisted of 342 443 Finnish biobank participants from FinnGen Data Freeze 10 (53% women) aged 40–108 with combined genotype and health registry data. Associations between PGS HGS and a total of 27 clinical endpoints were explored with linear or Cox regression models. Results A higher PGS HGS was associated with a reduced risk of selected common noncommunicable diseases and mortality by 2%–10%. The risk for these medical conditions decreased by 5%–23% for participants in the highest PGS HGS quintile compared to those in the lowest PGS HGS quintile. A 1 standard deviation (SD) increase in the PGS HGS predicted a lower body mass index (β = −0.112 kg/m2, standard error [ SE ] = 0.017, p  = 1.69E-11) in women but not in men (β = 0.004 kg/m2, p  = .768). PGS HGS was not associated with better survival after acute adverse health events compared to the nondiseased period. Conclusions The genotype that supports higher muscle strength appears to protect against future health adversities, albeit with modest effect sizes. Further research is needed to investigate whether or how a favorable lifestyle modifies this intrinsic capacity to resist diseases, and if the impacts of lifestyle behavior on health differs due to genetic predisposition for muscle strength. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: The sex gap in life expectancy has been narrowing in Finland over the past 4-5 decades; however, on average, women still live longer than men. Epigenetic clocks are markers for biological aging which predict life span. In this study, we examined the mediating role of lifestyle factors on the association between sex and biological aging in younger and older adults.Methods: Our sample consists of younger and older twins (21‒42 years, n = 1 477; 50‒76 years, n = 763) including 151 complete younger opposite-sex twin pairs (21‒30 years). Blood-based DNA methylation was used to compute epigenetic age acceleration by 4 epigenetic clocks as a measure of biological aging. Path modeling was used to study whether the association between sex and biological aging is mediated through lifestyle-related factors, that is, education, body mass index, smoking, alcohol use, and physical activity.Results: In comparison to women, men were biologically older and, in general, they had unhealthier life habits. The effect of sex on biological aging was partly mediated by body mass index and, in older twins, by smoking. Sex was directly associated with biological aging and the association was stronger in older twins.Conclusions: Previously reported sex differences in life span are also evident in biological aging. Declining smoking prevalence among men is a plausible explanation for the narrowing of the difference in life expectancy between the sexes. Data generated by the epigenetic clocks may help in estimating the effects of lifestyle and environmental factors on aging and in predicting aging in future generations. [ABSTRACT FROM AUTHOR]

Background: Epigenetic clocks are composite markers developed to predict chronological age or mortality risk from DNA methylation (DNAm) data. The present study investigated the associations between 4 epigenetic clocks (Horvath's and Hannum's DNAmAge and DNAm GrimAge and PhenoAge) and physical functioning during a 3-year follow-up.Method: We studied 63- to 76-year-old women (N = 413) from the Finnish Twin Study on Aging. DNAm was measured from blood samples at baseline. Age acceleration (AgeAccel), that is, discrepancy between chronological age and DNAm age, was determined as residuals from linear model. Physical functioning was assessed under standardized laboratory conditions at baseline and at follow-up. A cross-sectional analysis was performed with path models, and a longitudinal analysis was conducted with repeated measures linear models. A nonrandom missing data analysis was performed.Results: In comparison to the other clocks, GrimAgeAccel was more strongly associated with physical functioning. At baseline, GrimAgeAccel was associated with lower performance in the Timed Up and Go (TUG) test and the 6-minute walk test. At follow-up, significant associations were observed between GrimAgeAccel and lowered performance in the TUG, 6-minute and 10-m walk tests, and knee extension and ankle plantar flexion strength tests.Conclusions: The DNAm GrimAge, a novel estimate of biological aging, associated with decline in physical functioning over the 3-year follow-up in older women. However, associations between chronological age and physical function phenotypes followed similar pattern. Current epigenetic clocks do not provide strong benefits in predicting the decline of physical functioning at least during a rather short follow-up period and restricted age range. [ABSTRACT FROM AUTHOR]

Background. This study examined the relative contribution of genetic and environmental effects on the air-conducted hearing threshold level (0.5-4 kHz) and speech recognition threshold level of the better ear as well as self-reported hearing in older women. Methods. Hearing was measured as a part of the Finnish Twin Study on Aging in 103 monozygotic (MZ) and 114 dizygotic (DZ) female twin pairs aged 63-76 years. Audiometric measured hearing was tested using standardized methods in soundproof conditions. Self-reported hearing was assessed by a structured question. Quantitative genetic modeling was used for data analyses. Results. No significant differences in age, exposure to noise, hearing-aid use, auditory diseases or accidents, or number of self-reported chronic conditions or prescription medicines were observed between the MZ and DZ twins. A genetic component in common accounted for 75% (95% confidence interval [CI], 67%-81%) of the variance in the better ear's hearing threshold level and 54% (95% CI, 43%.64%) in the better ear's speech recognition threshold level, according to a bivariate genetic analysis. In addition, 10% (95% CI, 4%.15%) of the variance in the better ear's speech recognition threshold level was explained by its specific genetic component. Conclusion. Individual differences in audiometrically measured air-conducted hearing threshold level (0.5-4 kHz) and speech recognition threshold level in the better ear were largely accounted for by genetic differences between individuals. In contrast, self-reported hearing appears to be accounted for solely by environmental factors. [ABSTRACT FROM AUTHOR]

Background: Maintaining good fitness and good level of physical activity are important factors for maintaining physical independence later in life. The aim was to investigate the relationship between self-reported fitness and objectively measured physical activity and sedentary behavior in the elderly.Methods: Same-sex twin pairs born 1940-1944 in Finland were invited to the study. Altogether 787 individuals (mean age 72.9 years), of whom 404 were female, used a hip-worn triaxial accelerometer for at least 4 days and answered a question on perceived fitness. First, individual differences were studied between four fitness categories. Second, pairwise differences were examined among twin pairs discordant for fitness.Results: Self-reported fitness explained moderately the variation in objectively measured physical activity parameters: R2 for daily steps 26%, for daily mean metabolic equivalent 31%, for daily moderate-to-vigorous activity time 31%, and lower for sedentary behavior time 14% (all p < .001). Better self-reported fitness was associated with more steps taken on average (8,558 daily steps [very good fitness] vs 2,797 steps [poor fitness], p < .001) and with a higher amount of moderate-to-vigorous activity (61 min vs 12 min p < .001, respectively) in the adjusted multivariable model. Among 156 twin pairs discordant for self-reported fitness, co-twins with better fitness took more steps, did more moderate-to-vigorous activity, and had less sedentary behavior (all, p < .05) compared to their less fit co-twins; however, difference was smaller among monozygotic than dizygotic pairs.Conclusion: One simple question on self-reported fitness is associated with daily activity profile among community-dwelling older people. However, genetic factors modulate this association to some extent. [ABSTRACT FROM AUTHOR]

Background: The purpose of the study was to estimate the heritability of leukocyte telomere length (LTL) and lung function and to examine whether LTL and lung function share genetic or environmental effects in common.Methods: 386 monozygotic and dizygotic Finnish twin sisters (age 68.4±3.4 years) were included. Relative LTL was determined from peripheral blood DNA by qPCR. Lung function measures of FEV1, FVC, FEV1/FVC, and PEF were derived from spirometry. Genetic modeling was performed with MPlus statistical software.Results: Univariate analysis revealed that in LTL, 62% (95% confidence interval 50-72) of the variance was explained by additive genetic and 38% (28-50) by unique environmental factors. For FEV1, FVC, and PEF, the corresponding estimates were 65%-67% for additive genetic and 33%-35% for unique environmental factors. Across the sample, the phenotypic correlation between LTL and FEV1 was modest (r = .104, p = .041). Bivariate correlated factors model revealed that the genetic correlation between LTL and FEV1 was .18 (-0.19 to 0.64) and environmental correlation was -.10 (-0.84 to 0.55).Conclusions: Both LTL and lung function variables are moderately to highly genetically determined. The associations between LTL and the lung function variables were weak. However, the positive genetic correlation point estimate gave minor suggestions that, in a larger sample, genetic factors in common might play a role in the phenotypic correlation between LTL and FEV1. Future studies with larger samples are needed to confirm these preliminary findings. [ABSTRACT FROM AUTHOR]

Background. Mobility decline, the coexistence of several sensory difficulties and fear of falling (FOF) are all common concerns in older people; however, knowledge about the combined effect of FOF and coexisting sensory difficulties on mobility is lacking. Methods. Data on self-reported FOF, difficulties in hearing, vision, balance, and walking 2 km were gathered with a structured questionnaire among 434 women aged 63–76 years at baseline and after a 3-year follow-up. Logistic regression models were used for analyses. Results. Every third participant reported difficulties in walking 2 km at baseline. In cross-sectional analysis, the odds ratio for difficulties in walking 2 km was higher among persons who reported FOF compared with persons without FOF and the odds increased with the increasing number of sensory difficulties. Persons who reported FOF and who had three sensory difficulties had almost fivefold odds (odds ratio = 4.7, 95% confidence interval = 1.9–11.7) for walking difficulties compared with those who reported no FOF and no sensory difficulties. Among the 290 women without walking difficulties at baseline, 54 participants developed difficulty in walking 2 km during the 3-year follow-up. Odds ratio for incident walking difficulty was 3.5 (95% confidence interval = 1.6–7.8) in participants with FOF and with 2–3 sensory difficulties compared with persons without FOF and with at most one sensory difficulty at baseline. Conclusions. Older women who have several coexisting sensory difficulties combined with FOF are particularly vulnerable to mobility decline. Avoidance of walking as a result of FOF is likely to be reinforced when multiple sensory difficulties hinder reception of accurate information about the environment, resulting in accelerated decline in walking ability. [ABSTRACT FROM PUBLISHER]

Background. Inability to maintain balance while standing increases risk of falls in older people. The present study assessed whether center of pressure (COP) movement measured with force platform technology predicts risk for falls among older people with no manifest deficiency in standing balance. Methods. Participants were 434 community-dwelling women, aged 63-76 years. COP was measured in six stances on a force platform. Following balance tests, participants reported their falls with 12 monthly calendars. Incidence rate ratios (IRR) with 95% confidence intervals (CI) were computed from negative binomial regression models. For the analysis, those with ≥1 fall indoors were coded "indoor fallers," those with ≥1 fall outdoors, but no indoor falls, were coded "outdoor fallers." Outcome in the models was number of falls. Analyses were repeated including only participants without fall history prior to follow-up. Results. Among 198 fallers, there were 57 indoor and 132 outdoor fallers. The participants in the highest COP movement tertile, irrespective of the balance test, had a two- to fourfold risk for indoor falls compared to participants in the lowest COP tertile of the test. Inability to complete the tandem stance was also a significant predictor of the fall risk. The trend for increased risk for indoor falls was found also for participants in the highest COP movement tertile and without fall history. The COP movement in balance tests was not associated with outdoor falls. Conclusion. Force platform balance tests provide valid information of postural control that can be used to predict fall risk even among older people without apparent balance problems or fall history. When the force platform is not available, tandem stance provides a screening tool to show increased fall risk in community-dwelling older people. [ABSTRACT FROM AUTHOR]

Background: This study examined the relative contribution of genetic and environmental effects on the air-conducted hearing threshold level (0.5-4 kHz) and speech recognition threshold level of the better ear as well as self-reported hearing in older women.Methods: Hearing was measured as a part of the Finnish Twin Study on Aging in 103 monozygotic (MZ) and 114 dizygotic (DZ) female twin pairs aged 63-76 years. Audiometric measured hearing was tested using standardized methods in soundproof conditions. Self-reported hearing was assessed by a structured question. Quantitative genetic modeling was used for data analyses.Results: No significant differences in age, exposure to noise, hearing-aid use, auditory diseases or accidents, or number of self-reported chronic conditions or prescription medicines were observed between the MZ and DZ twins. A genetic component in common accounted for 75% (95% confidence interval [CI], 67%-81%) of the variance in the better ear's hearing threshold level and 54% (95% CI, 43%-64%) in the better ear's speech recognition threshold level, according to a bivariate genetic analysis. In addition, 10% (95% CI, 4%-15%) of the variance in the better ear's speech recognition threshold level was explained by its specific genetic component.Conclusion: Individual differences in audiometrically measured air-conducted hearing threshold level (0.5-4 kHz) and speech recognition threshold level in the better ear were largely accounted for by genetic differences between individuals. In contrast, self-reported hearing appears to be accounted for solely by environmental factors. [ABSTRACT FROM AUTHOR]

Background. This study examined the role of genetic and environmental factors explaining individual differences in women's walking ability in old age. Methods. A maximal walking speed test over 10 meters and a 6-minute walking endurance test were done under standard conditions among 92 monozygotic and 105 dizygotic pairs of twin sisters reared together, aged 63-75 years. Results. The mean maximum walking speed was 1.73 ± 0.32 m/s and the mean distance covered in the 6 minute walking test was 525.6 ± 77.3 m. Multivariate genetic modeling showed that a minor part of the variances in walking speed (16%, 95% confidence interval [CI]: 0%-54%) and endurance (20%, 95% CI: 0%-56%) were accounted for by genetic influences, and that the genetic influences were common to both traits. The corresponding proportions for common environmental factors were 37% (95% CI: 4%-58%) and 26% (95% CI: 0%-52%), and for individual environmental factors 46% (95% CI: 35%-59%) and 54% (95% CI 42%-68%), respectively. The environmental effects were partially common to both trails. Conclusions. Among relatively healthy older women, a modest portion of the variances of walking speed and endurance were accounted for by genetic factors, whereas shared and individual environmental factors explained most of the variance in both traits. [ABSTRACT FROM AUTHOR]

Background. Among older people, distraction while walking may increase the risk of falls. Factors underlying individual differences in dual tasking are not fully understood. Our aim was to study the effect of a second task on maximal walking speed and to examine whether individual differences in walking speed measured with and without a second task are accounted for by genetic and environmental influences shared across tasks or specific to each task. Methods. The data were collected from the 101 monozygotic and 116 dizygotic twin pairs aged 63-76 years recruited from the Finnish Twin Cohort. Maximal walking speed (MWS) over 10 m was measured on a laboratory corridor and timed with photocells. The test was repeated while subjects performed, first, a manual task (MWSmanual) and, second. a verbal task (MWSverbal). Results. Mean walking speed without a simultaneous task was 1.72 m/s (standard deviation [SD] 0.33), with a manual task it was 1.52 m/s (SD 0.26), and with a verbal task it was 1.36 m/s (SD 0.27). Multivariate genetic analysis showed that an additive genetic factor in common accounted lot 17% of individual differences in MWS, 19% in MWSmanual, and 12% in MWSverbal. In addition, MWSverbal had a genetic factor specific to it accounting for 10% of the variance. Shared environmental influences, common to all three traits, accounted for 39%, 27%, and 21% of the individual differences, respectively. Conclusion. Approximately half of the individual differences in walking with or without another task were accounted for by genetic and nongenetic familial effects in common, and the rest of the variation was accounted for by unique environmental factors in common and factors specific to walking tests. [ABSTRACT FROM AUTHOR]