Biomedical subjects

Stefania Bandinelli

Publications and source records attributed to Stefania Bandinelli.

At least 55 records · Page 3Linked to original sources

PubMed2005

Executive function correlates with walking speed in older persons: the InCHIANTI study.

OBJECTIVES: To study the association between performance on psychological tests of executive function and performance on lower extremity tasks with different attentional demands in a large sample of nondemented, older adults. DESIGN: Cross-sectional study. SETTING: Community-based. PARTICIPANTS: Nine hundred twenty-six persons aged 65 and older, without dementia, stroke, parkinsonism, visual impairment, or current treatment with neuroleptics, enrolled in a large epidemiological study. MEASUREMENTS: Trail Making Test (TMT) parts A and B and two performance-based measures of lower extremity function that require different executive/attentional-demanding skills: walking speed on a 4-m course at usual pace and walking speed on a 7-m obstacle course at fast pace. A difference score (Delta TMT), obtained by subtracting time to perform part A from time to perform part B of the TMT, was used as an indicator of executive function. Based on Delta TMT, subjects were divided into poor performance, intermediate performance, and good performance. RESULTS: After adjustment, no association between Delta TMT and 4-m course usual-pace walking speed was found. Participants with poor Delta TMT and with intermediate Delta TMT performance were more likely to be in the lowest tertile for 7-m obstacle course walking speed. CONCLUSION: In nondemented older persons, executive function is independently associated with tasks of lower extremity function that require high attentional demand.

Aged↗

PubMed2004

The origins of age-related proinflammatory state.

We hypothesized that the rising levels of inflammatory markers with aging is explained by cardiovascular risk factors and morbidity becoming progressively more prevalent in older persons. Information on inflammatory markers, cardiovascular risk factors, and diseases was collected in 595 men and 748 women sampled from the general population (age, 20-102 years). In both men and women, older age was associated with higher levels of interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1ra), IL-18, C-reactive protein (CRP), and fibrinogen, while soluble IL-6 receptor (sIL-6r) increased significantly with age only in men. Adjusting for cardiovascular risk factors and morbidity, the age regression coefficients became substantially smaller in models predicting IL-6, IL-1ra, IL-18, and fibrinogen and larger in the model predicting sIL6r. Adjustment for cardiovascular morbidity substantially reduced the effect of age on CRP in men but not in women. Findings were confirmed in a subgroup of 51 men and 45 women with low risk profile and no cardiovascular morbidity. Part of the "proinflammatory state" in older persons is related to the high prevalence of cardiovascular risk factor and morbidity.

Adult↗

PubMed2004

Bone density and hemoglobin levels in older persons: results from the InCHIANTI study.

Hypoxemia has been recognized as a risk factor for bone loss. The aim of the present study is to investigate the relationship of bone mass and density measures with anemia and hemoglobin levels in a large sample of older community-dwelling persons. The study is based on data from 950 participants enrolled in the "Invecchiare in Chianti" (Aging in the Chianti area, InCHIANTI) study. All the analyses were performed considering continuous hemoglobin levels as well as the dichotomous anemia variable (defined according to WHO criteria as hemoglobin < 12 g/dl in women and < 13 g/dl in men). A peripheral quantitative computerized tomography (pQCT) scan of the right calf was performed in all participants to evaluate total bone density, trabecular bone density, cortical bone density, and the ratio between cortical and total bone area. Linear regression analyses were used to assess the multivariate relationship of pQCT bone measures with anemia and hemoglobin levels after adjustment for demographics, chronic conditions, muscle strength and biological variables. Participants were 75.0 (SD 6.9) years old. In our sample, 101 participants (10.6%) were anemic. In women, coefficients from adjusted linear regression analyses evaluating the association between pQCT bone measures (per SD increase) and hemoglobin levels/anemia showed significant associations of anemia with total bone density (beta = -0.335, SE = 0.163; P = 0.04) and cortical bone density (beta = -0.428, SE = 0.160; P = 0.008). Relationships with borderline significance were found for the associations of anemia with trabecular bone density and the ratio between cortical and total bone area. Significant associations were found between hemoglobin levels and trabecular bone density (beta = 0.112, SE = 0.049; P = 0.02), total bone density (beta = 0.101, SE = 0.046; P = 0.03), cortical bone density (beta = 0.100, SE = 0.046; P = 0.03) and the ratio between cortical bone and total area (beta = 0.092, SE = 0.045; P = 0.04). In men, significant associations were found for hemoglobin levels with total bone density (beta = 0.076, SE = 0.036; P = 0.03) and cortical bone density (beta = 0.095, SE = 0.41; P = 0.02). A borderline significance was reported for the association between anemia and cortical bone density. We concluded that anemia and low hemoglobin levels are negatively and independently associated with bone mass and density. The bone loss associated with hemoglobin levels mainly occurs in the cortical bone. Women with lower hemoglobin levels demonstrate a higher bone loss than male counterparts.

Aged↗

PubMed2004

Neurological examination findings to predict limitations in mobility and falls in older persons without a history of neurological disease.

PURPOSE: To estimate the prevalence of neurological signs and their association with limitations in mobility and falls in a sample of older persons without known neurological disease. METHODS: A neurologist examined 818 participants from the InCHIANTI study who were aged > or =65 years and who did not have cognitive impairment, treatment with neuroleptics, and a history of neurological disease. Mobility was assessed as walking speed and self-reported ability to walk at least 1 km without difficulty. Participants were asked to report falls that had occurred in the previous 12 months. RESULTS: Less than 20% (160/818) of participants had no neurological signs. Neurological signs were more prevalent in older participants and those with impaired mobility. When all neurological signs were included in sex-and age-adjusted multivariate models, 10 were mutually independent correlates of poor mobility. After adjusting for age and sex, the number of neurological signs was associated with progressively slower walking speed (P <0.001), a higher probability of reported inability to walk 1 km (P <0.001), and a history of falls (P <0.05). CONCLUSION: Neurological signs are independent correlates of limitations in mobility and falls in older persons who have no clear history of neurological disease.

Accidental Falls↗

PubMed2004

Screening for poor performance of lower extremity in primary care: the Camucia Project.

BACKGROUND AND AIMS: Individuals with poor lower extremity performance are prime candidates for disability prevention. The Camucia Project is a collaborative study between geriatricians and primary care physicians (PCPs) testing the hypothesis that PCPs can use a simple performance-based test to identify older persons with poor lower extremity function, without excessive interference with their clinical routine. We also hypothesized that the number needed to screen (NNTS) a positive case would be lower in physicians' clinics than in the general population. METHODS: 23 PCPs administered the short physical performance battery (SPPB) to 360 consecutive, non-disabled and non-demented, 70- to 79-year-old outpatients. PCPs were asked to: 1) evaluate the feasibility and usefulness of administering the SPPB; 2) ascertain selected diseases according to predefined criteria; 3) identify causes of poor lower extremity function in patients with a SPPB score < or =9. NNTS from this study were compared with those estimated in non-disabled and non-demented, 70- to 79-year-old persons randomly selected from the InCHIANTI study population. RESULTS: The majority of PCPs (20/23) reported that using the SPPB to evaluate older patients was feasible and useful. The NNTS in the outpatient clinics was lower than in the InCHIANTI participants (1.6 vs 4.3). Poor lower extremity performance was attributed to musculo-skeletal diseases in 75%, to more than one cause in 55% (128/234), and to no specific cause in 16.2% (37/234) of the participants with SPPB < or =9. CONCLUSIONS: Screening of older persons with poor lower extremity perfomance by PCPs is feasible and efficient.

Aged↗

PubMed2004

A flame burning within.

Inflammation is a human being's primary defense against threats to homeostasis that are encountered every day. Especially in old age, when regulatory mechanisms responsible for inflammatory responses may be ineffective or damaged, the result can be adverse pathological conditions, and an increased risk of morbidity and mortality. The inflammation response is a plastic network composed of redundant signaling among several different mediators. These mediators have a reciprocal relationship with other biological sub-systems, including hormone regulation, the autonomic nervous system, and oxidative/anti-oxidant balance. Studying this complex architecture requires parallel and multiple research strategies from epidemiological to biochemical level, from observational studies to innovative intervention approaches. Given that the inflammatory response is a critical age-related process, understanding its regulatory action is essential in avoiding hazardous consequences in old age.

Aged↗

PubMed2004

Hemoglobin levels and skeletal muscle: results from the InCHIANTI study.

BACKGROUND: Anemia is associated with reduced physical performance and muscle strength. The aim of the study was to explore whether anemia and hemoglobin levels are associated with differences in quantitative and qualitative measures of muscle and fat. METHODS: The study sample consisted of 909 participants 65 years and older enrolled in the "Invecchiare in Chianti" (InCHIANTI) study, a prospective population-based study of older people aimed at identifying risk factors for late-life disability. All the analyses were performed considering continuous hemoglobin levels as well as the dichotomous anemia variable (defined according to World Health Organization criteria as hemoglobin <12 g/dL in women and <13 g/dL in men). A peripheral quantitative computed tomography (pQCT) scan was performed in all participants to evaluate total, muscular, and fat cross-sectional areas of the calf and relative muscle density. Ankle extension strength was measured using a hand-held dynamometer. Linear regression analyses were used to assess the multivariate relationship of pQCT and skeletal muscle strength measures with hemoglobin levels and anemia after adjustment for demographics, chronic conditions, medication use, and other biological variables. RESULTS: Participants were aged 74.8 +/- 6.8 years. In our sample, 94 participants (10.3%) were anemic. Hemoglobin levels were significantly associated with muscle density (beta = 0.225 [SE, standard error 0.098], p=.02), muscle area/total area ratio (beta=0.778 [SE 0.262], p=.003), fat area/total area ratio (beta=-0.869 [SE 0.225]; p<.001). Skeletal muscle strength and muscle density were highly associated with anemia (beta=-3.266 [SE 1.173], p=.005 and beta=-0.816 [SE 0.374], p=.03, respectively). Results did not change when analyses were rerun in a restricted sample of participants not affected by major medical conditions. CONCLUSION: The present study shows that hemoglobin levels are associated with the parameters of body composition obtained by pQCT, and that decreases in muscular strength measures occur in the presence of anemia.

Aged↗

PubMed2004

Effect of DHEAS on skeletal muscle over the life span: the InCHIANTI study.

BACKGROUND: It has been suggested that the reduced production of dehydroepiandrosterone sulfate (DHEAS) may be partially responsible for the decline of muscle strength and mass that often occurs with aging. However, this hypothesis has been only tested in small series of normal volunteers, with little consideration for potential confounders. Using data from a representative sample of 558 men (20-95 years) we tested the hypothesis that circulating DHEAS is independently associated with muscle strength and mass. METHODS: Data are from InCHIANTI, an epidemiological study conducted in the Chianti geographic area (Tuscany, Italy). DHEAS serum levels were related to lower extremity muscle strength assessed by hand-held dynamometry and calf muscle area estimated from quantitative computerized tomography. Confounders included age, anthropometrics, physical activity, smoking, energy and alcohol intake, albumin, lipids, interleukin-6, comorbidity, depressive symptoms, and disability in activities of daily living. RESULTS: In fully adjusted models predicting lower extremity muscle strength and calf muscle area, we found significant age*log DHEAS interactions, suggesting that the relationship between DHEAS levels and muscle parameters differs across the life span. In age-stratified models adjusted for confounders, serum DHEAS was an independent predictor of muscle strength (p <.02) and mass (p <.01), but only for men between 60 and 79 years of age. After adjusting these models for serum-free or bioavailable testosterone, results were unchanged. CONCLUSIONS: In men aged 60-79 years, circulating DHEAS is an independent correlate of muscle strength and calf muscle area. The possible causal role of declining DHEAS in age-related sarcopenia should be further explored in longitudinal studies.

Adult↗

PubMed2004

Diverse effect of inflammatory markers on insulin resistance and insulin-resistance syndrome in the elderly.

OBJECTIVES: To evaluate the potential association between different inflammatory markers and insulin resistance (IR), as well as insulin-resistance syndrome (IRS) in a large, population-based study of older, nondiabetic persons. DESIGN: Cross-sectional study. SETTING: Outpatient clinic in Greve in Chianti and Bagno a Ripoli (Italy). PARTICIPANTS: One thousand one hundred forty-six nondiabetic subjects ranging in age from 22 to 104. MEASUREMENTS: Anthropometric measurements; plasma fasting levels of glucose, insulin, and cholesterol (total, high-density lipoprotein, low-density lipoprotein); homeostasis model assessment to estimate degree of insulin resistance; tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), soluble IL-6 receptor (sIL-6R), interleukin receptor antagonist (IL-1ra), and C-reactive protein (CRP) plasma concentrations; diastolic, systolic, and mean arterial blood pressure; and echo-color-Doppler duplex scanning examination of carotid arteries. RESULTS: Insulin resistance correlated with age (r=0.102; P<.001) and plasma levels of TNF-alpha (r=0.082; P=.007), IL-1ra (r=0.147; P<.001), IL-6 (r=0.133; P<.001), sIL-6R (r=-0.156; P<.001), and CRP (r=0.83; P<.001). Subjects in the upper tertile of IR degree were older and had higher serum levels of TNF-alpha, IL-1ra, and IL-6 and lower levels of sIL-6R than subjects in the lowest tertile. Independent of age, sex, body mass index, waist-to-hip ratio, triglycerides, drug intake, diastolic blood pressure, smoking habit, and carotid atherosclerotic plaques, higher IL-6 (t=2.987; P=.003) serum concentrations were associated with higher IR, whereas sIL-6R levels (t=-5.651; P<.001) were associated with lower IR. Furthermore, IL-1ra concentrations (t=2.448; P=.015) were associated with IRS, and higher sIL-6R plasma levels continued to correlate negatively with IRS. CONCLUSION: Different inflammatory markers are associated with a diverse effect on IR and IRS in elderly nondiabetic subjects.

Adult↗

PubMed2004

Impairments of muscles and nerves associated with peripheral arterial disease and their relationship with lower extremity functioning: the InCHIANTI Study.

OBJECTIVES: To define the relationships between lower extremity peripheral arterial disease (PAD), pathophysiological findings in lower extremity muscles and nerves, and lower extremity performance. DESIGN: Cross-sectional. SETTING: Two communities in Italy. PARTICIPANTS: Nine-hundred seventy-nine community-dwelling men and women aged 60 and older (109 with PAD). MEASUREMENTS: Presence and degree of lower extremity arterial obstruction were determined using the ankle-brachial index (ABI). Lower extremity muscle cross-sectional area was measured using computed tomography. Peroneal nerve conduction velocity (NCV) and leg power were also determined. Measures of lower extremity functioning were fast walking speed over 4 meters, time required to walk 400 meters, and the summary performance score. RESULTS: Participants with PAD had significantly poorer performance on functional outcomes than participants without PAD. Adjusting for age and sex, presence of PAD was associated with reduced leg muscle power (83.69 vs 103.51 watts, P<.001), reduced muscle cross-sectional area (61.5 vs 63.5 cm2, P=.14), and reduced NCV (43.0 vs 44.2 m/s, P=.003). Adjustment for leg power diminished the independent association between ABI and the functional outcomes measures. CONCLUSION: In community-dwelling individuals, PAD is associated with reduced NCV and reduced muscle power in the lower extremities. Muscle power may mediate the association between lower ABI levels and poorer functional performance.

Adult↗

PubMed2004

Insulin resistance and executive dysfunction in older persons.

OBJECTIVES: To evaluate the association between insulin resistance (IR) and executive dysfunction in a large, population-based study of older persons without diabetes mellitus (DM) or dementia. DESIGN: Cross-sectional study. SETTING: Outpatient clinic in Greve in Chianti and Bagno a Ripoli, Italy. PARTICIPANTS: A total of 597 subjects aged 65 to 93 without DM or dementia. MEASUREMENTS: Anthropometric measurements; plasma fasting levels of glucose, insulin, cholesterol (total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol), and insulin-like growth factor-1 (IGF-1); homeostasis model assessment (HOMA) to estimate degree of IR; Trail Making Test (TMT) A; TMT-B; TMT-B minus TMT-A (DIFF B-A); and Mini-Mental State Examination (MMSE). RESULTS: IR (HOMA) was associated with longer TMT-B (correlation coefficient (r)=0.11; P=.006) and DIFF B-A times (r=0.10; P=.022). Subjects in the upper tertile of IR were older and had longer TMT-B and DIFF B-A than participants in the lowest tertile. After adjusting for age, sex, and years of formal education, IR was significantly correlated with TMT-A, TMT-B, and DIFF B-A. After adjusting for age, sex, education, body mass index, waist:hip girth ratio, HDL-C, triglycerides, IGF-1, hypertension, drug intake, and physical activity, the results did not significantly change. After introducing MMSE score into the model, IR continued to be an independent determinant of TMT-A (beta=11.005; P=.021), TMT-B (beta=28.379; P<.001), and DIFF B-A (beta=17.374; P=.011). CONCLUSION: IR is independently associated with frontal cortex function evidenced by poor TMT times in older persons without DM or dementia.

Adult↗

PubMed2003

Nursing home case-mix instruments: validation of the RUG-III system in Italy.

BACKGROUND AND AIMS: The current Italian reimbursement system for long-term care does not adequately consider the great variability in the health and functional status of older persons who are admitted to long-term care institutions. Furthermore, no procedure is implemented to monitor the quality of care provided to older residents. We conducted this study to verify whether the RUG-III (Resource Utilization Groups-version III), a tool for assessing the case-mix of nursing home residents, which is widely used in the United States and in many European countries, can be effectively used in the Italian health care system. METHODS: We administered an Italian version of the RUG-III to 1000 older residents of 11 intermediate- and long-term care institutions. We also collected objective information on the amount of care provided directly or indirectly to each resident by nurses, physical therapists, and other health professionals. RESULTS: The RUG-III 44 group classification system explained 61 and 44% of the variance in rehabilitative and nursing wage-adjusted care time, respectively. CONCLUSIONS: Our findings provide strong evidence that the RUG-III classification, applied to Italian intermediate- and long-term care institutions, provides a robust estimate of the amount of nursing and rehabilitation resources consumed by older residents.

Diagnosis-Related Groups↗

PubMed2003

High-frequency vibration training increases muscle power in postmenopausal women.

OBJECTIVE: To test whether training on a high-frequency (28Hz) vibrating platform improves muscle power and bone characteristics in postmenopausal women. DESIGN: Randomized controlled trial with 6-month follow-up. SETTING: Outpatient clinic in a general hospital in Italy. PARTICIPANTS: Twenty-nine postmenopausal women (intervention group, n=14; matched controls, n=15). INTERVENTION: Participants stood on a ground-based oscillating platform for three 2-minute sessions for a total of 6 minutes per training session, twice weekly for 6 months. The controls did not receive any training. Both groups were evaluated at baseline and after 6 months. MAIN OUTCOME MEASURES: Muscle power, calculated from ground reaction forces produced by landing after jumping as high as possible on a forceplate, cortical bone density, and biomarkers of bone turnover. RESULTS: Over 6 months, muscle power improved by about 5% in women who received the intervention, and it remained unchanged in controls (P=.004). Muscle force remained stable in both the intervention and control groups. No significant changes were observed in bone characteristics. CONCLUSION: Reflex muscular contractions induced by vibration training improve muscle power in postmenopausal women.

Analysis of Variance↗

PubMed2003

The frailty syndrome: a critical issue in geriatric oncology.

Evidence exists that the geriatric intervention guided by Comprehensive Geriatric Assessment (CGA) has positive effects on a number of important health outcomes in frail older patients. Although a number of observational studies, editorials, special articles and clinical reports, suggest that CGA should be used to guide the assessment and clinical decision-making in older cancer patients, there is limited support to this view in the literature. Older patients that are diagnosed with cancer are usually healthier and less problematic than persons of the same age who are randomly sampled from the general population. In these persons, the cancer dominates the clinical picture and, therefore, instruments especially tuned for the frail elderly may provide little information. The concept of the frailty syndrome, characterized by high susceptibility, low functional reserve and unstable homeostasis, has recently received a lot of attention by the geriatric community. A CGA approach, which also evaluates elements of the frailty syndrome, may be of great interest for those oncologists who want to identify older patients likely to develop severe toxicity and severe side effects in response to aggressive treatment. Improvements in the definition of the frailty syndrome may profit from the clinical experience of oncologists.

Adaptation, Physiological↗

PubMed2003

Mild cognitive deterioration with subcortical features: prevalence, clinical characteristics, and association with cardiovascular risk factors in community-dwelling older persons (The InCHIANTI Study).

OBJECTIVES: To identify subjects with minimal or mild nonamnestic cognitive impairment with parkinsonian stance and gait and investigate vascular correlates of this condition. DESIGN: First wave of an epidemiological longitudinal study (InCHIANTI) on factors predicting loss of mobility in older persons. SETTING: The Chianti geographic area (Tuscany, Italy). PARTICIPANTS: Five hundred fifty-six subjects aged 70 to 90 with Mini-Mental State Examination (MMSE) scores greater than 23 of 30, of the 1,260 persons aged 65 and older randomly selected from the population registry of Greve in Chianti and Bagno a Ripoli, two small towns near Florence. METHODS: Low cognitive performance (LCP) was defined as an age- and education-adjusted MMSE below the 50th percentile for the InCHIANTI population. Subcortical features were plastic rigidity on neurological examination (parkinsonism), gait disturbance (small-step gait or parkinsonian gait), and dysexecutive features. Two hundred forty-three participants had high cognitive performance, 166 had LCP without subcortical features, and 75 had LCP with subcortical features. Vascular risk factors were hypertension, atrial fibrillation or pathological findings on electrocardiogram (ECG), low serum high-density lipoprotein (HDL) or high low-density lipoprotein cholesterol, diabetes mellitus, obesity, and heavy smoking. RESULTS: Three main vascular risk factors were significantly more prevalent in LCP with subcortical features: hypertension (P =.02), atrial fibrillation or ECG changes (P =.04), and low HDL cholesterol (P =.001). LCP with subcortical features was significantly associated with cerebrovascular risk factors (P =.001). CONCLUSION: Gait disturbance and nonamnestic cognitive symptoms might be the consequence of subcortical vascular damage.

Aged↗

PubMed2003

Age and disability affect dietary intake.

The purpose of the study was to provide information on dietary intake in the InCHIANTI study population, a representative sample (n = 1453) of persons living in two towns of Tuscany (Italy), including a large number of old and very old individuals (79.5% >65 y old). We also investigated whether difficulties in nutrition-related activities were associated with inadequate intake of selected nutrients. The percentage of persons with an inadequate intake of nutrients according to Italian Recommended Nutrients Levels (LARN) was higher in the older age groups. Older persons tended to adapt their diets in response to individual functional difficulties, often leading to monotonous food consumption and, as a consequence, to inadequate nutrient intakes. Multiple logistic models were used to evaluate whether inadequate intake of selected nutrients could be predicted by nutrition-related difficulties. Reporting difficulties in three or more nutrition-related activities (chewing, self-feeding, shopping for basic necessities, carrying a shopping bag, cooking a warm meal, using fingers to grasp or handle) significantly increased the risk of inadequate intake of energy [odds ratio (OR) = 3.8, 95% CI = 1.9-7.8) and vitamin C (OR = 2.2, 95% CI = 1.2-4.2, after adjustment for energy intake). More attention to functional problems in the elderly population and the provision of formal or informal help to those who have difficulty in purchasing, processing and eating food may reduce, at least in part, the percentage of older persons with poor nutrition.

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↗

PubMed2002

Chronic inflammation and the effect of IGF-I on muscle strength and power in older persons.

Deregulation of the inflammatory response plays a major role in the age-related decline of physical performance. The causal pathway leading from inflammation to disability has not been fully clarified, but several researches suggest that interleukin-6 (IL-6) causes a reduction of physical performance in elderly through its effect on muscle function. In vitro studies demonstrated that IL-6 inhibits the secretion of insulin-like growth factor I (IGF-I) and its biological activity, suggesting that the negative effect of IL-6 on muscle function might be mediated through IGF-I. We evaluated the joint effect of IGF-I and IL-6 on muscle function in a population-based sample of 526 persons with a wide age range (20-102 yr). After adjusting for potential confounders, such as age, sex, body mass index, IL-6 receptor, and IL-6 promoter polymorphism, IL-6, IGF-I, and their interaction were significant predictors of handgrip and muscle power. In analyses stratified by IL-6 tertiles, IGF-I was an independent predictor of muscle function only in subjects in the lowest IL-6 tertile, suggesting that the effect of IGF-I on muscle function depends on IL-6 levels. This mechanism may explain why IL-6 is a strong risk factor for disability.

Adult↗