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Taina Rantanen

Publications and source records attributed to Taina Rantanen.

31 records · Page 2Linked to original sources
PubMed2005

Shared genetic and environmental effects on strength and power in older female twins.

PURPOSE: This study examined the relative contribution of genetic and environmental effects on maximal leg extensor power and also investigated whether leg extensor power and maximum voluntary isometric knee extensor strength share a genetic component. METHODS: Muscle functions were measured as part of the Finnish Twin Study on Aging in 101 monozygotic (MZ) and 116 dizygotic (DZ) female twin pairs aged 63-76 yr. Leg extensor power was measured using the Nottingham Leg Extensor Power Rig and maximum voluntary isometric knee extensor strength using an adjustable dynamometer chair. The analyses were carried out using the maximum likelihood method in Mx-program on the raw data set. RESULTS: A bivariate Cholesky decomposition model showed that leg extensor power and isometric knee extensor strength shared a genetic component in common, which accounted for 32% of the total variance in leg extensor power and 48% in isometric knee extensor strength. In addition, power and strength had a nonshared environmental effect in common accounting for four percent of the variance in power and 52% in strength. Remaining variance for leg extensor power was due to trait-specific shared and nonshared environmental effects. CONCLUSION: Observed genetic effect in common for leg extensor power and maximum voluntary isometric knee extensor strength indicated that these two traits are regulated by the same genes. However, also environmental effects have a significant role in explaining the variability in power and strength.

Aged↗
PubMed2004

Determinants of lower-body muscle power in early postmenopausal women.

OBJECTIVES: To investigate the association between muscle size, density, and fiber composition; body composition; maximal isometric knee extension strength (KES); and lower-body muscle power in healthy postmenopausal women. DESIGN: Cross-sectional analysis of baseline data from a 1-year randomized controlled experiment. SETTING: University-based research laboratory. PARTICIPANTS: Seventy-eight healthy postmenopausal women aged 50 to 57. MEASUREMENTS: Maximal lower-body muscle power was assessed using vertical jump height (VJH). Maximal isometric KES was measured on a dynamometer chair. Computed tomography scans were used to determine lean-tissue cross-sectional area and density of the thigh and lower leg muscles. Relative area occupied by type I, IIa, IIax, and IIx muscle fibers was assessed from the vastus lateralis muscle. lean body mass and total body fat mass were assessed using bioelectrical impedance. RESULTS: High VJH was associated with low body fat mass, high KES, and high density of thigh and lower leg muscles. Multivariate linear regression modeling revealed that high thigh muscle density (beta=0.242; P=.019), relative area occupied by the fastest muscle fiber types (IIax+IIx; beta=0.246; P=.007), KES (beta=0.247; P=.007), and low body fat mass (beta=-0.455; P<.001) were independently associated with high VJH, accounting for 45% of the variability in VJH. CONCLUSION: This study showed that thigh muscle composition, muscle strength, and body fat mass are important determinants of lower-body muscle power production during weight-bearing activity in healthy postmenopausal women.

Aged↗
PubMed2004

Oral health status and change in handgrip strength over a 5-year period in 80-year-old people.

OBJECTIVE: The number of remaining teeth may indicate the extent of life-long exposure to inflammation, a known risk factor for muscle loss and consequent disability. The aim was to study dental health status as a risk factor for muscle strength loss in very old people. DESIGN: Cross-sectional and prospective cohort study over a 5-year follow-up. SETTING: Research laboratory. PARTICIPANTS: One hundred and ninety-three 80-year-old people participated in the baseline examinations. Five years later, 79 survivors were retested. MAIN OUTCOME MEASURES: Number of remaining teeth, presence of periodontitis and handgrip strength. RESULTS: At baseline, grip strength of men correlated positively with number of teeth but not with the presence of periodontitis. In women, the cross-sectional associations were not statistically significant. In the prospective analyses, the presence of periodontitis at baseline showed a clear association with a steeper decline in handgrip over the 5-year follow-up in both sexes. The values adjusted for gender, height, weight, number of chronic conditions and physical activity were -28.3% (SE 5.7) among those with periodontitis vs. -11.9% (SE 3.1, p = 0.015) among those with healthy gingiva. No association between the number of teeth at baseline and change in grip strength over 5 years was observed. CONCLUSIONS: The presence of oral inflammation may lead to loss in muscle strength increasing the risk of disability. Therefore, good dental care throughout the life span may decrease risk of disability in old age.

Aged↗
PubMed2004

The genetic and environmental effects on depressive symptoms among older female twins.

The aim of the present study was to examine the contribution of genetic and environmental factors to depressive symptoms among older women. The participants were 102 monozygotic and 115 dizygotic female twin pairs aged 64 to 76 years. Depressive symptoms were assessed by the Center for the Epidemiologic Studies Depression Scale. The contribution of genetic and environmental effects was estimated for the constructed depressiveness factor and for the subscales which were depressed mood, psychomotor retardation, lack of wellbeing and interpersonal difficulties. Of the variance in depressiveness, shared environmental influences accounted for 39% and nonshared environmental influences 61%. For the subscales, 24% to 62% of the variance was explained by individual, and 13% to 23% by shared, environmental factors. Lack of wellbeing had its own moderate additive genetic effect explaining 30% of the variance. This study showed that in older women predominantly environmental factors underlay individual differences in depressiveness; however, the factors varied to some extent between dimensions measured by the subscales.

Aged↗
PubMed2003

Heritability of maximal isometric muscle strength in older female twins.

The purpose of the present study was to examine genetic and environmental effects on maximal isometric handgrip, knee extension, and ankle plantar flexion strength. In addition, we wanted to investigate whether the strength of these three muscle groups shares a genetic component or whether the genetic effect is specific for each muscle group. Muscle strength was measured as part of the Finnish Twin Study on Aging in 97 monozygotic (MZ) and 102 dizygotic (DZ) female twin pairs, aged 63-76 yr. The MZ and DZ individuals did not differ from each other in age, body height, weight, or self-related health. The age-adjusted pairwise (intraclass) correlations of the MZ and DZ twins were, respectively, 0.462 and 0.242 in knee extension, 0.435 and 0.345 in handgrip, and 0.512 and 0.435 in ankle plantar flexion strength. The multivariate genetic analysis showed that handgrip and knee extension strength shared a genetic component, which accounted for 14% (95% confidence interval: 4-28%) of the variance in handgrip strength and 31% (95% confidence interval: 18-45%) in knee extension strength. The influence of genetic effects on ankle plantar flexion strength was minor and not significant. Furthermore, these three muscle groups had a nongenetic familial effect in common and nonshared environmental effects in common. The results suggested that muscle strength is under a genetic regulation, but also environmental effects have a significant role in explaining the variability in the muscle strength.

Aged↗
PubMed2003

Contribution of genetic and environmental effects to postural balance in older female twins.

The aim of the present study was to determine the relative roles of genetic and environmental influences on postural balance in older women. The participants were 97 monozygotic (MZ) and 102 dizygotic (DZ) female twins, aged 64-76 yr. Postural sway was measured during side-by-side stance with eyes open and eyes closed, and during semitandem stance with eyes open on a force platform. Sway data were condensed into four first-order and one second-order latent factors. The second-order factor, named balance, incorporates sway data from multiple tests and thus best describes the phenotype of postural balance. The contribution of genetic and environmental influences on the variability of the latent factors was assessed by using structural equation modeling. Additive genetic influences accounted for 35% and shared environmental influences accounted for 24% of the total variance in the balance factor. In the present study, postural balance in older women had a moderate genetic component. Genetic influences on postural balance may be mediated through gene variation in the systems that control posture. The finding that individual environmental influences accounted for almost one-half of the variance in postural balance points to the potential of targeted interventions to maintain and improve balance control in older persons.

Aged↗
PubMed2003

Handgrip strength and cause-specific and total mortality in older disabled women: exploring the mechanism.

OBJECTIVES: To examine the association between muscle strength and total and cause-specific mortality and the plausible contributing factors to this association, such as presence of diseases commonly underlying mortality, inflammation, nutritional deficiency, physical inactivity, smoking, and depression. DESIGN: Prospective population-based cohort study with mortality surveillance over 5 years. SETTING: Elderly women residing in the eastern half of Baltimore, Maryland, and part of Baltimore County. PARTICIPANTS: Nine hundred nineteen moderately to severely disabled women aged 65 to 101 who participated in handgrip strength testing at baseline as part of the Women's Health and Aging Study. MEASUREMENTS: Cardiovascular disease (CVD), cancer, respiratory disease, other measures (not CVD, respiratory, or cancer), total mortality, handgrip strength, and interleukin-6. RESULTS: Over the 5-year follow-up, 336 deaths occurred: 149 due to CVD, 59 due to cancer, 38 due to respiratory disease, and 90 due to other diseases. The unadjusted relative risk (RR) of CVD mortality was 3.21 (95% confidence interval (CI) = 2.00-5.14) in the lowest and 1.88 (95% CI = 1.11-3.21) in the middle compared with the highest tertile of handgrip strength. The unadjusted RR of respiratory mortality was 2.38 (95% CI = 1.09-5.20) and other mortality 2.59 (95% CI = 1.59-4.20) in the lowest versus the highest grip-strength tertile. Cancer mortality was not associated with grip strength. After adjusting for age, race, body height, and weight, the RR of CVD mortality decreased to 2.17 (95% CI = 1.26-3.73) in the lowest and 1.56 (95% CI = 0.89-2.71) in the middle, with the highest grip-strength tertile as the reference. Further adjustments for multiple diseases, physical inactivity, smoking, interleukin-6, C-reactive protein, serum albumin, unintentional weight loss, and depressive symptoms did not materially change the risk estimates. Similar results were observed for all-cause mortality. CONCLUSION: In older disabled women, handgrip strength was a powerful predictor of cause-specific and total mortality. Presence of chronic diseases commonly underlying death or the mechanisms behind decline in muscle strength in chronic disease, such as inflammation, poor nutritional status, disuse, and depression, all of which are independent predictors of mortality, did not explain the association. Handgrip strength, an indicator of overall muscle strength, may predict mortality through mechanisms other than those leading from disease to muscle impairment. Grip strength tests may help identify patients at increased risk of deterioration of health.

Aged↗
PubMed2003

Age-associated changes in skeletal muscles and their effect on mobility: an operational diagnosis of sarcopenia.

Sarcopenia, the reduction of muscle mass and strength that occurs with aging, is widely considered one of the major causes of disability in older persons. Surprisingly, criteria that may help a clinician to identify persons with impaired muscle function are still lacking. Using data from a large representative sample of the general population, we examined how muscle function and calf muscle area change with aging and affect mobility in men and women free of neurological conditions. We tested several putative indicators of sarcopenia, including knee extension isometric torque, handgrip, lower extremity muscle power, and calf muscle area. For each indicator, sarcopenia was considered to be present when the measure was >2 SDs below the mean. For all four measures, the prevalence of sarcopenia increased with age, both in men and women. The age-associated gradient in prevalence was maximum for muscle power and minimum for calf-muscle area. However, lower extremity muscle power was no better than knee-extension torque or handgrip in the early identification of poor mobility, defined either as walking speed <0.8 m/s or inability to walk at least 1 km without difficulty and without developing symptoms. Optimal cutoff values that can be used in the clinical practice to identify older persons with poor mobility were developed. The findings of the study lay the basis for a cost-effective, clinical marker of sarcopenia based on a measure of isometric handgrip strength. Our findings should be verified in a longitudinal study.

Adult↗
PubMed2003

Knee osteoarthritis compromises early mobility function: The Women's Health and Aging Study II.

OBJECTIVE: To examine associations between osteoarthritis (OA) of the knee and early functional limitations in a cohort of high-functioning older women, and evaluate the contributions of muscle strength, body weight, and pain severity to these limitations. Methods. Cross sectional analyses were conducted on baseline data of the Women's Health and Aging Study II (WHAS II), an observational study of disability transitions in a cohort of women aged 70-79 upon entry and who were representative of the one-third highest-functioning community-resident women. Standardized questionnaires and examinations were used to assess knee OA features, medication use, pain severity, knee extensor muscle strength, and body weight. Functional limitation was assessed using validated performance measures and self-report measures of task modification and task difficulty. RESULTS: Sixty-nine women classified as "symptomatic" for knee OA, 48 with "asymptomatic/intermittently symptomatic," knee OA, and 285 with "no knee OA" were included in the final analysis. Despite selection for their high level of self-reported function, performance was slower and task modification was more frequently reported among women with knee OA than women without knee OA. Lower knee extensor strength, higher body weight, and greater pain severity were associated with knee OA, and also with functional limitations. Conclusion. Knee OA appeared to be associated with early functional limitations in this cohort of high-functioning, older, community-resident women. Lower knee extensor strength, higher body weight, and pain severity were closely associated with these limitations. The extent to which modification of these factors attenuates knee OA associated functional decline should be investigated.

Activities of Daily Living↗
PubMed2002

A randomized controlled trial of rehabilitation after hospitalization in frail older women: effects on strength, balance and mobility.

When frail older people become acutely ill, they are at increased risk of further functional deterioration and rehabilitation is needed to restore functioning. The effects of an out-patient multicomponent training program including strength training after hospitalization were studied in a randomized controlled trial. Sixty-eight women (mean age 83.0 +/- 3.9 years) who were hospitalized due to an acute illness and were mobility impaired at admission were randomized into training (N = 34) and home exercise (N = 34) groups. Maximal voluntary isometric strength of knee extension and hip abduction, dynamic balance, and maximal walking speed were measured before and after the 10-week training period, and 3 and 9 months after the end of the intervention. After the intervention, significant improvements were observed in the training group compared to the home exercise group in the maximal voluntary isometric knee extension strength (20.8% vs. 5.1%, P= 0.009), balance scale (+ 4.4 points vs. -1.3 points, P= 0.001) and walking speed (+ 0.12 m s-1 vs. -0.05 m s-1, P= 0.022). Effects on knee extension and hip abduction strength, balance and walking speed were observed 3 months later, and some effects on hip abduction strength (9.0% vs. -11.8%, P= 0.004) and mobility were still apparent even 9 months after the intervention.

Aged↗
PubMed2002

Muscle strength as a predictor of onset of ADL dependence in people aged 75 years.

The aim of this prospective study over 5 years was to examine maximal isometric strength of multiple muscle groups as a predictor of losing independence in activities of daily living (ADL). The participants were from the Nordic Research on Aging (NORA75). These analyses are restricted to 567 people who at baseline were independent in ADL and participated in strength tests, and who five years later participated in follow-up ADL assessments. Tests on maximal isometric strength of hand grip, elbow flexion, knee extension and trunk flexion and extension were done using adjustable dynamometers. For each muscle group tested, three equal groups were formed for men and women separately based on distributions of results. Those who reported being unable or needing help for eating, dressing, bathing, toileting, walking indoors or transferring from a bed or a chair were rated as ADL dependent. Of the 227 initially ADL independent men, 21 (9.3%) became dependent in ADL. In women, the figures were 30 (8.8%) of 340. Multiple logistic regression models were used to predict the risk of ADL dependence in groups based on strength tertiles. After confirming that the association of muscle strength and incident ADL-dependence was similar in men and women, both genders were included in the same analyses adjusted for body weight and height, gender and research locality. Gender specific cut-offs were used for strength tertiles. All the strength tests predicted ADL dependence, with those being in the lowest tertile having two to three times greater risks than those in the highest tertile of strength. Further adjustments for chronic diseases did not materially change the results. Strength tests could be used to identify people who are still independent in ADL but who are at increased risk of becoming dependent because of poor muscle strength, and who could reduce their risk by strengthening exercises.

Activities of Daily Living↗
PubMedDate not supplied

Change in subjective age among older people over an eight-year follow-up: 'getting older and feeling younger?'.

The purpose of this prospective study was to describe changes in subjective age over an 8-year period among community-dwelling people aged 65 to 84 years in Finland. At the baseline 1155 respondents met study criteria and 451 of these participated in the follow-up study. Participants described in years the age they felt themselves to be (feel age) and their preferred age (ideal age). Discrepancy scores relative to chronological age were calculated for feel age and ideal age. No significant mean-level changes were observed in the age discrepancy scores over the 8-year time frame. The baseline discrepancy between chronological and feel age remained constant among 48% of the participants, with 26% reporting a younger and 26% an older feel age. Similar patterns were observed in the discrepancy between chronological age and ideal age. The findings point both to stability and to individual variability in feel and preferred age identification over time in older adults.

Adaptation, Psychological↗