Biomedical subjects

Marjolein Visser

Publications and source records attributed to Marjolein Visser.

At least 19 recordsLinked to original sources

PubMed2026

Genetics of major depressive disorder in a homogeneous population with uniform phenotyping.

Harmonized phenotyping and diverse population-specific studies are crucial for advancing gene discovery in psychiatric genetics. We conducted a genome-wide association (GWAS) mega-analysis of DSM-defined lifetime major depressive disorder (MDD) in 64 941 participants (25.7% cases) from the Dutch BIObanks Netherlands Internet Collaboration (BIONIC) consortium. Liability-scale SNP-based heritability was 12.0% (SE = 1.4%) as estimated by LDSC (assuming a lifetime prevalence of 15%) and 26.6% (SE = 1.1%) when estimated by LDAK-REML on individual-level genotype data, indicating substantial common-variant signal in this clinically harmonized sample. The genetic correlation with the latest major depression GWAS from the Psychiatric Genomics Consortium (PGC-MD) was high (rG = 0.89, SE = 0.048). Polygenic scores (PGSs) based on BIONIC predicted depression in UK Biobank, and PGSs derived from PGC-MD predicted MDD in BIONIC, supporting transferability of depression polygenic signal across cohorts and phenotype definitions. Within-family PGS analyses in twins suggested that the observed prediction was not primarily driven by detectable family-level confounding, and twin concordance for MDD increased with polygenic burden. We identified one genome-wide significant locus, indexed by rs3818852 in PALMD, but this finding currently lacks independent replication and should be interpreted cautiously. Finally, genetic correlation and latent causal variable analyses identified multiple traits showing shared or directionally consistent genetic associations with MDD. Together, these findings underscore the value of clinically harmonized phenotyping in regional biobank collaborations for studying the genetic architecture of MDD.

Humans↗

PubMed2006

Daily activity energy expenditure and mortality among older adults.

CONTEXT: Exercise is associated with mortality benefits but simply expending energy through any activity in an individual's free-living environment may confer survival advantages. OBJECTIVE: To determine whether free-living activity energy expenditure is associated with all-cause mortality among older adults. DESIGN, SETTING, AND PARTICIPANTS: Free-living activity energy expenditure was assessed in 302 high-functioning, community-dwelling older adults (aged 70-82 years). Total energy expenditure was assessed over 2 weeks using doubly labeled water. Resting metabolic rate was measured using indirect calorimetry and the thermic effect of meals was estimated at 10% of total energy expenditure. Free-living activity energy expenditure was calculated as: (total energy expenditure x 0.90) - resting metabolic rate. Participants were followed up over a mean of 6.15 years (1998-2006). MAIN OUTCOME MEASURES: Free-living activity energy expenditure (3 tertiles: low, <521 kcal/d; middle, 521-770 kcal/d; high, >770 kcal/d) and all-cause mortality. RESULTS: Fifty-five participants (18.2%) died during follow-up. As a continuous risk factor, an SD increase in free-living activity energy expenditure (287 kcal/d) was associated with a 32% lower risk of mortality after adjusting for age, sex, race, study site, weight, height, percentage of body fat, and sleep duration (hazard ratio, 0.68; 95% confidence interval, 0.48-0.96). Using the same adjustments, individuals in the highest tertile of free-living activity energy expenditure were at a significantly lower mortality risk compared with the lowest tertile (hazard ratio, 0.31; 95% confidence interval, 0.14-0.69). Absolute risk of death was 12.1% in the highest tertile of activity energy expenditure vs 24.7% in the lowest tertile; absolute risks were similar to these for tertiles of physical activity level. The effect of free-living activity energy expenditure changed little after further adjustment for self-rated health, education, prevalent health conditions, and smoking behavior. According to self-reports, individuals expending higher levels of free-living activity energy were more likely to work for pay (P = .004) and climb stairs (P = .01) but self-reported high-intensity exercise, walking for exercise, walking other than for exercise, volunteering, and caregiving did not differ significantly across the activity energy expenditure tertiles. CONCLUSIONS: Objectively measured free-living activity energy expenditure was strongly associated with lower risk of mortality in healthy older adults. Simply expending energy through any activity may influence survival in older adults.

Activities of Daily Living↗

PubMed2006

Vitamin D status in relation to one-year risk of recurrent falling in older men and women.

BACKGROUND: Falls frequently occur in the elderly and are a major cause of morbidity and mortality. OBJECTIVE: The objective of the study was to prospectively investigate the association between serum 25-hydroxyvitamin D [25(OH)D] levels and risk of recurrent falling in older men and women. DESIGN: This was a prospective cohort study. SETTING: An age- and sex-stratified random sample of the Dutch older population was determined. SUBJECTS: Subjects included 1231 men and women (aged 65 yr and older) participating in the Longitudinal Aging Study Amsterdam. MEASUREMENTS: Baseline serum 25(OH)D was determined by a competitive protein binding assay. During 1 yr, falls were prospectively recorded by means of a fall calendar. RESULTS: Low 25(OH)D (<10 ng/ml) was associated with an increased risk of falling. After adjustment for age, sex, education level, region, season, physical activity, smoking, and alcohol intake, the odds ratios (95% confidence interval) were 1.78 (1.06-2.99) for subjects who experienced two falls or more as compared with those who did not fall or fell once and 2.23 (1.17-4.25) for subjects who fell three or more times as compared with those who fell two times or less. There was a statistically significant effect modification by age, and stratified analyses (<75 and > or = 75 yr) showed that the associations were particularly strong in the younger age group; the odds ratios (95% confidence interval) were 5.21 (2.03-13.40) for two falls or more and 4.96 (1.52-16.23) for three falls or more. CONCLUSIONS: Poor vitamin D status is independently associated with an increased risk of falling in the elderly, particularly in those aged 65-75 yr.

Accidental Falls↗

PubMed2006

Inflammatory markers and loss of muscle mass (sarcopenia) and strength.

PURPOSE: The objective of this study was to investigate whether high levels of serum interleukin (IL)-6, C-reactive protein (CRP), and alpha1-antichymotrypsin (ACT) were associated with the loss of muscle strength or muscle mass (sarcopenia) in older persons. SUBJECTS: The study included 986 men and women of the Longitudinal Aging Study Amsterdam, with a mean age of 74.6 years (standard deviation 6.2). METHODS: Grip strength (n = 986) and appendicular muscle mass (n = 328, using dual-energy x-ray absorptiometry) were obtained in 1995 and 1996 and repeated after a 3-year follow-up. Loss of muscle strength was defined as a loss of grip strength greater than 40%, and sarcopenia was defined as a loss of muscle mass greater than 3%, approximating the lowest 15% of the study sample. RESULTS: Multiple linear and logistic regression analyses revealed that higher levels of IL-6 were associated with greater decline in muscle strength, which decreased by -3.21 kg (standard error 0.81) per standard deviation increase in log-transformed IL-6. After adjustment for confounders, including sociodemographic, health, and lifestyle factors, high IL-6 (>5 pg/mL) and high CRP (>6.1 mug/mL) were associated with a 2 to 3-fold greater risk of losing greater than 40% of muscle strength. Persons with high levels of ACT (>181% of the normal human pooled plasma) were 40% less likely to experience loss of muscle strength and tended (P = .07) to have a smaller decline in muscle mass compared with those in the lowest quartile of ACT. No consistent associations of IL-6 and CRP with sarcopenia were found. CONCLUSION: The findings of this prospective, population-based study suggest that higher levels of IL-6 and CRP increase the risk of muscle strength loss, whereas higher levels of ACT decrease the risk of muscle strength loss in older men and women.

Aged↗

PubMed2006

Low serum concentrations of 25-hydroxyvitamin D in older persons and the risk of nursing home admission.

BACKGROUND: The prevalence of vitamin D deficiency in nursing home patients is high. OBJECTIVE: We aimed to ascertain whether lower serum 25-hydroxyvitamin D [25(OH)D] concentrations increase the risk of future nursing home admission and early death. DESIGN: We included 1260 independent, community-dwelling persons aged > or =65 y who were participating in the Longitudinal Aging Study Amsterdam (1995-1996). Study outcomes were time to nursing home admission during 6 y of follow-up and time to death until 1 April 2003. RESULTS: Vitamin D deficiency [25(OH)D < 25 nmol/L] and insufficiency [25(OH)D = 25-49.9 nmol/L] were present in 127 (10.1%) and 462 (36.7%) subjects, respectively. During follow-up, 138 subjects (11.0%) were admitted to nursing homes, and 380 subjects (30.2%) died. The risk of nursing home admission for participants with 25(OH)D deficiency was 53 cases per 1000 person-years higher than that for those with high 25(OH)D (> or =75 nmol/L) concentrations (58 compared with 5 cases). After adjustment for potential confounders, the hazard ratio (95% CI) of nursing home admission was 3.48 (1.39, 8.75) for vitamin D-deficient, 2.77 (1.17, 6.55) for vitamin D-insufficient, and 1.92 (0.79, 4.66) for vitamin D-borderline persons as compared with persons with high 25(OH)D (P for trend = 0.002). The results remained after additional adjustment for frailty indicators. Lower 25(OH)D was associated with higher mortality risk, but this association was not significant after adjustment for frailty indicators. CONCLUSION: Lower serum 25(OH)D concentrations in older persons are associated with a greater risk of future nursing home admission and may be associated with mortality.

Aged↗

PubMed2006

Strength, but not muscle mass, is associated with mortality in the health, aging and body composition study cohort.

BACKGROUND: Although muscle strength and mass are highly correlated, the relationship between direct measures of low muscle mass (sarcopenia) and strength in association with mortality has not been examined. METHODS: Total mortality rates were examined in the Health, Aging and Body Composition (Health ABC) Study in 2292 participants (aged 70-79 years, 51.6% women, and 38.8% black). Knee extension strength was measured with isokinetic dynamometry, grip strength with isometric dynamometry. Thigh muscle area was measured by computed tomography (CT) scan, and leg and arm lean soft tissue mass were determined by dual energy x-ray absorptiometry (DXA). Both strength and muscle size were assessed as in gender-specific Cox proportional hazards models, with age, race, comorbidities, smoking status, level of physical activity, fat area by CT or fat mass by DXA, height, and markers of inflammation, including interleukin-6, C-reactive protein, and tumor necrosis factor-alpha considered as potential confounders. RESULTS: There were 286 deaths over an average of 4.9 (standard deviation = 0.9) years of follow-up. Both quadriceps and grip strength were strongly related to mortality. For quadriceps strength (per standard deviation of 38 Nm), the crude hazard ratio for men was 1.51 (95% confidence interval, 1.28-1.79) and 1.65 (95% confidence interval, 1.19-2.30) for women. Muscle size, determined by either CT area or DXA regional lean mass, was not strongly related to mortality. In the models of quadriceps strength and mortality, adjustment for muscle area or regional lean mass only slightly attenuated the associations. Further adjustment for other factors also had minimal effect on the association of quadriceps strength with mortality. Associations of grip strength with mortality were similar. CONCLUSION: Low muscle mass did not explain the strong association of strength with mortality, demonstrating that muscle strength as a marker of muscle quality is more important than quantity in estimating mortality risk. Grip strength provided risk estimates similar to those of quadriceps strength.

Age Factors↗

PubMed2006

The loss of skeletal muscle strength, mass, and quality in older adults: the health, aging and body composition study.

BACKGROUND: The loss of muscle mass is considered to be a major determinant of strength loss in aging. However, large-scale longitudinal studies examining the association between the loss of mass and strength in older adults are lacking. METHODS: Three-year changes in muscle mass and strength were determined in 1880 older adults in the Health, Aging and Body Composition Study. Knee extensor strength was measured by isokinetic dynamometry. Whole body and appendicular lean and fat mass were assessed by dual-energy x-ray absorptiometry and computed tomography. RESULTS: Both men and women lost strength, with men losing almost twice as much strength as women. Blacks lost about 28% more strength than did whites. Annualized rates of leg strength decline (3.4% in white men, 4.1% in black men, 2.6% in white women, and 3.0% in black women) were about three times greater than the rates of loss of leg lean mass ( approximately 1% per year). The loss of lean mass, as well as higher baseline strength, lower baseline leg lean mass, and older age, was independently associated with strength decline in both men and women. However, gain of lean mass was not accompanied by strength maintenance or gain (ss coefficients; men, -0.48 +/- 4.61, p =.92, women, -1.68 +/- 3.57, p =.64). CONCLUSIONS: Although the loss of muscle mass is associated with the decline in strength in older adults, this strength decline is much more rapid than the concomitant loss of muscle mass, suggesting a decline in muscle quality. Moreover, maintaining or gaining muscle mass does not prevent aging-associated declines in muscle strength.

Aged↗

PubMed2006

Influence of marital status on physical activity levels among older adults.

PURPOSE: The purpose of these analyses was to describe the levels and types of activity in relationship to current marital status among older adults and determine if the physical activity level of the husband was related to the physical activity level of his wife. METHODS: Participants included 3075 well-functioning white and black men and women aged 70-79 yr with further examination of 345 spousal pairs. Marital status was self-reported and participants were grouped as married versus not married. Based on responses to a leisure-time questionnaire, total physical activity was calculated and participants were classified as low or high active. Descriptive statistics were used to describe level and proportions of type of activity by marital status. Logistic regression was used to determine if marital status was an important determinant of physical activity participation. Regression models were adjusted for demographics, body mass index (BMI), and chronic disease conditions. RESULTS: When compared with their single counterparts, married men reported higher median levels of exercise participation (P = 0.008) and married women reported higher levels of total (P < 0.0001) and nonexercise activity (P < 0.0001) with a trend toward higher exercise participation (P = 0.05). In spousal pairs, compared with men in the low active group, highly active men were almost three times as likely (OR = 2.97; 95% CI = 1.73, 5.10) to have a similarly active spouse. The model only modestly attenuated when adjusted for age, BMI, and health status of the husband [OR = 2.49 (1.41, 4.42)]. CONCLUSIONS: Marital status and spousal physical activity (PA) levels are important determinants for PA participation among older adults.

Aged↗

PubMed2006

Diabetes, hyperglycemia, and inflammation in older individuals: the health, aging and body composition study.

OBJECTIVE: The objective of this study was to assess the association of inflammation with hyperglycemia (impaired fasting glucose [IFG]/impaired glucose tolerance [IGT]) and diabetes in older individuals. RESEARCH DESIGN AND METHODS: Baseline data from the Health, Aging and Body Composition study included 3,075 well-functioning black and white participants, aged 70-79 years. RESULTS: Of the participants, 24% had diabetes and 29% had IFG/IGT at baseline. C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) levels (P < 0.001) were significantly higher among diabetic participants and those with IFG/IGT. Odds of elevated IL-6 and TNF-alpha (>75th percentile) were, respectively, 1.95 (95% CI 1.56-2.44) and 1.88 (1.51-2.35) for diabetic participants and 1.51 (1.21-1.87) and 1.14 (0.92-1.42) for those with IFG/IGT after adjustment for age, sex, race, smoking, alcohol intake, education, and study site. Odds ratios for elevated CRP were 2.90 (2.13-3.95) and 1.45 (1.03-2.04) for diabetic women and men and 1.33 (1.07-1.69) for those with IFG/IGT regardless of sex. After adjustment for obesity, fat distribution, and inflammation-related conditions, IL-6 remained significantly related to both diabetes and IFG/IGT. CRP in women and TNF-alpha in both sexes were significantly related to diabetes, respectively, whereas risk estimates for IFG/IGT were decreased by adjustment for adiposity. Among diabetic participants, higher levels of HbA(1c) were associated with higher levels of all three markers of inflammation, but only CRP remained significant after full adjustment. CONCLUSIONS: Our findings show that dysglycemia is associated with inflammation, and this relationship, although consistent in diabetic individuals, also extends to those with IFG/IGT.

Aged↗

PubMed2005

Angiotensin-converting enzyme insertion/deletion genotype, exercise, and physical decline.

CONTEXT: Physical performance in response to exercise appears to be influenced by the angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) genotype in young adults, but whether this relationship could help explain variation in older individuals' response to exercise has not been well studied. OBJECTIVE: To determine whether the ACE genotype interacts with significant physical activity to affect the incidence of mobility limitation in well-functioning older adults. DESIGN, SETTING, AND PARTICIPANTS: The Health Aging and Body Composition (Health ABC) Cohort Study, conducted in the metropolitan areas of Memphis, Tenn, and Pittsburgh, Pa. A total of 3075 well-functioning community-dwelling adults aged 70 through 79 years were enrolled from 1997 to 1998 and had a mean of 4.1 years of follow-up. MAIN OUTCOME MEASURE: Incident mobility limitation defined as the report of difficulty walking a quarter of a mile (0.4 km) or walking up 10 steps on 2 consecutive semiannual interviews (n = 1204). RESULTS: Physically active participants (those reporting expending > or =1000 kcal/wk in exercise, walking, and stair climbing) were less likely to develop mobility limitation regardless of genotype. However, activity level interacted significantly with the ACE genotype (P = .002). In the inactive group, the ACE genotype was not associated with limitation (P = .46). In the active group, those with the II genotype were more likely to develop mobility limitation after adjusting for potential confounders compared with those with ID/DD genotypes (adjusted rate ratio, 1.45, 95% confidence interval, 1.08-1.94). The gene association was especially strong among participants reporting weightlifting. Exploration of possible physiological correlates revealed that among active participants, those with the II genotype had higher percentage of body fat (P = .02) and more intermuscular thigh fat (P = .02) but had similar quadriceps strength as those with ID/DD. CONCLUSIONS: Among older individuals who exercised, those with the ACE DD or ID genotypes were less likely to develop mobility limitation than those with the II genotype. Regardless of genotype, individuals who exercised were less likely to develop mobility limitation than those who did not exercise.

Aged↗

PubMed2005

Adiposity in relation to vitamin D status and parathyroid hormone levels: a population-based study in older men and women.

OBJECTIVE: In small case-control studies, obesity was associated with worse vitamin D status. Our aim was to assess the association of adiposity (anthropometric measures as well as dual energy x-ray absorptiometry) with serum 25-hydroxyvitamin D (25-OH-D) and serum PTH levels in a large population-based study including older men and women. METHODS: Subjects were participants of the Longitudinal Aging Study Amsterdam and were aged 65 yr and older. In 453 participants, serum 25-OH-D and PTH were determined, and body mass index, waist circumference, waist to hip ratio, sum of skin folds, and total body fat percentage by dual energy x-ray absorptiometry were measured. RESULTS: After adjustment for potential confounders, higher body mass index, waist circumference, and sum of skin folds were statistically significantly associated with lower 25-OH-D (standardized beta values were -0.136, -0.137, and -0.140, respectively; all P < 0.05) and with higher PTH (0.166, 0.113, and 0.114, respectively; all P < 0.05). Total body fat percentage was more strongly associated with 25-OH-D and PTH (-0.261 and 0.287, respectively; both P < 0.001) compared with anthropometric measures. Total body fat percentage remained associated with 25-OH-D after adjustment for PTH, and with PTH after adjustment for 25-OH-D. CONCLUSION: Precisely measured total body fat is inversely associated with 25-OH-D levels and is positively associated with PTH levels. The associations were weaker if anthropometric measures were used, indicating a specific role of adipose tissue. Regardless of the possible underlying mechanisms, it may be relevant to take adiposity into account when assessing vitamin D requirements.

Adipose Tissue↗

PubMed2005

Change in serum albumin and subsequent decline in functional status in older persons.

BACKGROUND AND AIMS: This study examines whether a three-year change in serum albumin concentration is associated with subsequent decline in functional status in older persons. METHODS: A total of 588 participants from the Longitudinal Aging Study Amsterdam aged 65-85 years were followed for six years. The three-year change in serum albumin was classified in four groups: chronic low (< or =43 g/L at both time points), decrease (decrease of 2.4% or more) from normal to low, decrease but still normal, and stable normal albumin (reference group). During the subsequent three years, absolute change and a decline of one standard deviation or more (termed substantial decline) in functional status was assessed. Functional status was measured in two ways: using performance tests and self-reported functional ability. RESULTS: Substantial decline in functional performance and functional ability was observed in 243 persons (41.3%) and 133 persons (22.6%), respectively. After adjustment for baseline functional status and potential confounders, chronic low albumin and a decrease from normal to low albumin were associated with a greater absolute decline in functional performance and in self-reported functional ability. Using the outcome substantial decline in functional status, only decrease to low serum albumin was associated with decline in functional ability [odds ratio (OR)=1.97; one-sided 95% Confidence Limit (CL)=1.09]. CONCLUSIONS: This study indicates that chronic low serum albumin is a determinant of decline in functional status. However, a decrease in serum albumin from normal to low levels but within the normal range was a stronger determinant of future decline in functional status. Change in serum albumin level within the normal range measured between two points in time may be used as a general marker of future functional decline.

Activities of Daily Living↗

PubMed2005

Lower serum albumin concentration and change in muscle mass: the Health, Aging and Body Composition Study.

BACKGROUND: Low albumin concentrations in older persons increase the risk of poor health outcomes, including functional decline. OBJECTIVE: The aim of the study was to investigate the association between serum albumin concentration and skeletal muscle loss (sarcopenia) in old age. DESIGN: Serum albumin concentration was measured in 1882 black and white men and women aged 70-79 y participating in the Health, Aging and Body Composition Study. Five-year changes in appendicular skeletal muscle mass (ASMM), total-body fat-free mass (FFM), and trunk lean mass (TLM) were measured by using dual-energy X-ray absorptiometry. Confounders included health and lifestyle factors, which are markers of inflammation and protein intake. RESULTS: A low albumin concentration (< 38 g/L) was observed in 21.2% of the study participants. After adjustment for confounders, the mean (+/-SE) change in ASMM was -82 +/- 26 g per 3-g/L lower albumin concentration (P = 0.002). This association remained after persons with a low albumin concentration (< 38 g/L) were excluded. The decline in ASMM in subjects with low albumin concentrations was almost 30% higher (-930 +/- 56 g) than that in those with albumin concentrations > or = 42 g/L (-718 +/- 38 g; P < 0.01). The association between albumin and change in ASMM remained after additional adjustment for weight change. A weak association was observed for FFM, whereas no association was observed for TLM, which suggests a specific role of albumin in skeletal muscle change. CONCLUSIONS: Lower albumin concentrations, even above the clinical cutoff of 38 g/L, are associated with future loss of ASMM in older persons. Low albumin concentration may be a risk factor for sarcopenia.

Absorptiometry, Photon↗

PubMed2005

Adipose tissue in muscle: a novel depot similar in size to visceral adipose tissue.

BACKGROUND: The manner in which fat depot volumes and distributions, particularly the adipose tissue (AT) between the muscles, vary by race is unknown. OBJECTIVE: The objective was to quantify a previously unstudied and novel intermuscular AT (IMAT) depot and subcutaneous AT, visceral AT (VAT), and total-body skeletal muscle mass in healthy sedentary African American (AA), Asian, and white adults by whole-body magnetic resonance imaging. IMAT is the AT between muscles and within the boundary of the muscle fascia. DESIGN: Analyses were conducted on 227 women [AA (n = 79): body mass index (BMI; in kg/m(2)), 29.0 +/- 5.5; age, 45.7 +/- 16.9 y; Asian (n = 38): BMI, 21.7 +/- 2.9; age, 47.2 +/- 19.9 y; whites (n = 110): BMI, 24.9 +/- 5.4; age, 43.7 +/- 16.2 y]) and 111 men [AA (n = 39): BMI, 25.6 +/- 3.2; age, 45.5 +/- 18.8 y; Asian (n = 13): BMI, 24.9 +/- 2.5; age, 45.6 +/- 25.0 y; white (n = 59): BMI, 25.8 +/- 3.8; age 44.5 +/- 16.3 y]. RESULTS: IMAT depots were not significantly different in size between race groups at low levels of adiposity; however, with increasing adiposity, AAs had a significantly greater increment in the proportion of total AT (TAT) than did the whites and Asians (58, 46, and 44 g IMAT/kg TAT, respectively; P = 0.001). VAT depots were not significantly different in size at low levels of adiposity but, with increasing adiposity, VAT accumulation was greater than IMAT accumulation in the Asians and whites; no significant differences were observed in AAs. CONCLUSION: Race differences in AT distribution extend to IMAT, a depot that may influence race-ethnicity differences in dysglycemia.

Adipose Tissue↗

PubMed2005

Weight change and the conservation of lean mass in old age: the Health, Aging and Body Composition Study.

BACKGROUND: Weight loss may contribute to the loss of lean mass with age. OBJECTIVE: The objective was to evaluate the relation between weight loss or weight gain and changes in lean mass and fat mass in older adults. DESIGN: We observed changes in weight and body composition during a 4-y period in 2163 men (47%) and women (53%) aged 70-79 y in the Health, Aging and Body Composition Study cohort. Whole-body and appendicular bone-free lean mass and fat mass were measured by using dual-energy X-ray absorptiometry. RESULTS: Weight loss and weight gain were common. In both weight losers and weight gainers, changes in lean mass as a percentage of initial lean mass were substantially smaller than changes in fat mass as a percentage of initial fat mass. However, the difference between the change in lean mass and that in fat mass was more pronounced with weight gain than with weight loss, especially in men. Small amounts of lean loss and fat gain were noted with weight stability. In multivariate models, weight loss was strongly associated with lean mass loss in both men and women, especially in men whose weight loss was concurrent with a hospitalization. CONCLUSIONS: With weight change, a greater proportion of lean mass than of fat mass was conserved, but, especially in older men, significantly more lean mass was lost with weight loss than was gained with weight gain. These findings suggest that weight loss, even with regain, could accelerate sarcopenia in older adults.

Absorptiometry, Photon↗

PubMed2005

Muscle mass, muscle strength, and muscle fat infiltration as predictors of incident mobility limitations in well-functioning older persons.

BACKGROUND: Lower muscle mass has been correlated with poor physical function; however, no studies have examined this relationship prospectively. This study aims to investigate whether low muscle mass, low muscle strength, and greater fat infiltration into the muscle predict incident mobility limitation. METHODS: Our study cohort included 3075 well-functioning black and white men and women aged 70-79 years participating in the Health, Aging, and Body Composition study. Participants were followed for 2.5 years. Muscle cross-sectional area and muscle tissue attenuation (a measure of fat infiltration) were measured by computed tomography at the mid-thigh, and knee extensor strength by using a KinCom dynamometer. Incident mobility limitation was defined as two consecutive self-reports of any difficulty walking one-quarter mile or climbing 10 steps. RESULTS: Mobility limitations were developed by 22.3% of the men and by 31.8% of the women. Cox's proportional hazards models, adjusting for demographic, lifestyle, and health factors, showed a hazard ratio of 1.90 [95% confidence interval (CI), 1.27-2.84] in men and 1.68 (95% CI, 1.23-2.31) in women for the lowest compared to the highest quartile of muscle area (p <.01 for trend). Results for muscle strength were 2.02 (95% CI, 1.39-2.94) and 1.91 (95% CI, 1.41-2.58), p <.001 trend, and for muscle attenuation were 1.91 (95% CI, 1.31-2.83) and 1.68 (95% CI, 1.20-2.35), p <.01 for trend. When included in one model, only muscle attenuation and muscle strength independently predicted mobility limitation (p < .05). Among men and women, associations were similar for blacks and whites. CONCLUSION: Lower muscle mass (smaller cross-sectional thigh muscle area), greater fat infiltration into the muscle, and lower knee extensor muscle strength are associated with increased risk of mobility loss in older men and women. The association between low muscle mass and functional decline seems to be a function of underlying muscle strength.

Aged↗

PubMed2005

The association of sex hormone levels with poor mobility, low muscle strength and incidence of falls among older men and women.

OBJECTIVE: The objective of this study was to examine whether low levels of oestradiol and testosterone are associated with impaired mobility, low muscle strength and the incidence of falls in a population-based sample of older men and women. DESIGN: Cross-sectional population-based study, based on data of the Longitudinal Ageing Study Amsterdam (LASA), including 623 men and 663 women, aged 65-88 years. MEASUREMENTS: Serum levels of oestradiol, testosterone, albumin and sex hormone-binding globulin (SHBG) were measured. Physical performance, functional limitations and muscle strength were assessed, and a follow-up on falls was performed prospectively within 3 years. RESULTS: After adjustment for age, level of education, alcohol use, physical activity, chronic disease and body mass index (BMI), men in the highest quartile of the oestradiol/SHBG ratio had significantly higher physical performance scores than men in the lowest quartile (beta = 0.103). Serum levels of total testosterone were positively associated with muscle strength (beta = 0.085). Calculated bioavailable testosterone levels were positively associated with physical performance and muscle strength (beta = 0.128 and 0.109 respectively). No associations of oestradiol levels with mobility were seen in women. Levels of oestradiol and testosterone were not associated with falls. CONCLUSIONS: It can be concluded that low levels of sex hormones were associated with impaired mobility and low muscle strength in men, but not in women. Levels of sex hormones were not associated with the incidence of falls neither in men, nor in women.

Accidental Falls↗

PubMed2005

Endocrine and inflammatory markers as predictors of frailty.

OBJECTIVE: To examine the association of serum concentrations of 25-hydroxyvitamin D [25(OH)D], interleukin-6 (IL-6), C-reactive protein (CRP) and IGF-1 with prevalent and incident frailty. DESIGN: The Longitudinal Aging Study Amsterdam (LASA), a prospective cohort study with 3-yearly measurement cycles. Setting General population-based sample. PARTICIPANTS: The respondents were men and women aged 65 and over, who participated at T1 (1995/1996, N = 1720) and T2 (1998/1999, N = 1509). Blood samples were obtained at T1 (N = 1271). Measurements The presence of frailty at T1 and 3-year incidence of frailty. Frailty is defined as the presence of three out of nine frailty indicators. RESULTS: At T1, 242 (19.0%) of all respondents were frail. Those who were frail at T1 had higher CRP and lower 25(OH)D levels. Serum 25(OH)D remained associated with frailty after adjustment for potential confounders with an odd ratios (OR) of 2.60 [95% confidence interval (95% CI) 1.60-4.21] for 25(OH)D < 25 nmol/l and 1.72 (95% CI 1.19-2.47) for 25(OH)D 25-50 nmol/l vs. high levels of 25(OH)D. Of the nonfrail at T1, 125 respondents (14.1%) became frail at T2. After adjustment, moderately elevated CRP levels (3-10 microg/ml) (OR 1.69, 95% CI 1.09-2.63) and low 25(OH)D (OR 2.04, 95% CI 1.01-4.13) were associated with incident frailty. No consistent associations were observed for IL-6 and IGF-1. CONCLUSION: Low 25(OH)D levels were strongly associated with prevalent and incident frailty; moderately elevated levels of CRP were associated with incident frailty.

Aged↗