Population-specific Cut-points Research Articles

Impact of Using Population-Specific Cut-Points, Self-Reported Health, and Socio-Economic Parameters to Predict Sarcopenia: A Cross-Sectional Study in Community-Dwelling Kosovans Aged 60 Years and Older.

The age-related decline of muscle strength, mass, and physical performance (sarcopenia) has been raising concerns among the scientific and healthcare communities. This decline may differ between populations, age groups, and sexes. Therefore, we aimed to explore sarcopenia together with the impact of health and socio-economic parameters in mature Kosovans. A cross-sectional study was conducted on community-dwelling adults aged ≥ 60 years (n = 240, 47.1% female) from the Prishtina region. Sarcopenia was identified using the following criteria: (i) the European Working Group in Sarcopenia for Older People (EWGSOP1), (ii) the revised EWGSOP2 algorithms, and (iii) sex-specific cut-points derived from the Kosovan population. In males, pre-sarcopenia/probable sarcopenia was detected from the EWGSOP1, EWGSOP2 and Kosovan-specific criteria at values of 3.1%, 5.5%, and 28.3%; sarcopenia was detected at 1.6%, 5.5%, and 0.0%, and severe sarcopenia was detected at 4.7%, 2.4%, and 4.7%, respectively. Pre-sarcopenia was lower in females (0.9%, 5.3%, 16.8%), with no cases of sarcopenia or severe sarcopenia detected by either algorithm. Sarcopenic males were older, had a lower weight, BMI, skeletal muscle mass, performance score, nutritional status (p < 0.001), educational level (p = 0.035), and higher malnourishment risk (p = 0.005). It is notable that high overweight and obesity levels were also detected (93.8% of females, 77.1% of males). This study highlights the importance of using population-specific cut-points when diagnosing sarcopenia, as otherwise its occurrence may be underestimated, especially in obese persons. Age, body composition, physical performance, health, and socio-economic conditions can influence the occurrence of sarcopenia.

Prevalence of Sarcopenia Employing Population-Specific Cut-Points: Cross-Sectional Data from the Geelong Osteoporosis Study, Australia.

Background: Prevalence estimates for sarcopenia vary depending on the ascertainment criteria and thresholds applied. We aimed to estimate the prevalence of sarcopenia using two international definitions but employing Australian population-specific cut-points. Methods: Participants (n = 665; 323 women) aged 60–96 years old were from the Geelong Osteoporosis Study. Handgrip strength (HGS) was measured by dynamometers and appendicular lean mass (ALM) by whole-body dual-energy X-ray absorptiometry. Physical performance was assessed using gait speed (GS, men only) and/or the timed up-and-go (TUG) test. Using cut-points equivalent to two standard deviations (SDs) below the mean young reference range from the same population and recommendations from the European Working Group on Sarcopenia in Older People (EWGSOP), sarcopenia was identified by low ALM/height2 (<5.30 kg for women; <6.94 kg for men) + low HGS (<16 kg women; <31 kg men); low ALM/height2 + slow TUG (>9.3 s); low ALM/height2 + slow GS (<0.8 m/s). For the Foundation for the National Institutes of Health (FNIH) equivalent, sarcopenia was identified as low ALM/BMI (<0.512 m2 women, <0.827 m2 men) + low HGS (<16 kg women, <31 kg men). Receiver Operating Characteristic curves were also applied to determine optimal cut-points for ALM/BMI (<0.579 m2 women, <0.913 m2 men) that discriminated poor physical performance. Prevalence estimates were standardized to the Australian population and compared to estimates using international thresholds. Results: Using population-specific cut-points and low ALM/height2 + HGS, point-estimates for sarcopenia prevalence were 0.9% for women and 2.9% for men. Using ALM/height2 + TUG, prevalence was 2.5% for women and 4.1% for men, and using ALM/height2 + GS, sarcopenia was identified for 1.6% of men. Using ALM/BMI + HGS, prevalence estimates were 5.5–10.4% for women and 11.6–18.4% for men. Conclusions: This study highlights the range of prevalence estimates that result from employing different criteria for sarcopenia. While population-specific criteria could be pertinent for some populations, a consensus is needed to identify which deficits in skeletal muscle health are important for establishing an operational definition for sarcopenia.

Sarcopenia Definitions and Their Associations With Mortality in Older Australian Women

ObjectivesTo investigate the relationship of 4 sarcopenia definitions with long-term all-cause mortality risk in older Australian women. DesignData from the Perth Longitudinal Study in Aging Women from 2003 to 2013 was examined in this prospective cohort study. The 4 sarcopenia definitions were the United States Foundation for the National Institutes of Health (FNIH), the European Working Group on Sarcopenia in Older People (EWGSOP), and adapted FNIH (AUS-POPF) and EWGSOP (AUS-POPE) definitions using Australian population-specific cut-points [<2 standard deviation (SD)] below the mean of young healthy Australian women. All-cause mortality was captured via linked data systems. Setting and ParticipantsIn total, 903 community-dwelling older Australian women (baseline mean age 79.9 ± 2.6 years) with concurrent measures of muscle strength (grip strength), physical function (timed-up-and-go; TUG) and appendicular lean mass (ALM) were included. MeasuresCox-proportional hazards modeling was used to examine the relationship between sarcopenia definitions and mortality over 5 and 9.5 years. ResultsBaseline prevalence of sarcopenia by the 4 definitions differed substantially [FNIH (9.4%), EWGSOP (24.1%), AUS-POPF (12.0%), AUS-POPE (10.7%)]. EWGSOP and AUS-POPE had increased age-adjusted hazard ratios (aHRs) for mortality over 5 years [aHR 1.88 95% confidence interval (CI) (1.24‒2.85), P < .01; aHR 2.52 95% CI (1.55‒4.09), P < .01, respectively] and 9.5 years (aHR 1.39 95% CI (1.06‒1.81), P = .02; aHR 1.94 95% CI (1.40‒2.69), P < .01, respectively). No such associations were observed for FNIH or AUS-POPF. Sarcopenia components including weaker grip strength (per SD, 4.9 kg; 17%) and slower TUG (per SD, 3.1 seconds; 40%) but not ALM adjusted-variants (ALM/body mass index or ALM/height2) were associated with greater relative hazards for mortality over 9.5 years. Conclusions/RelevanceUnlike FNIH, the EWGSOP sarcopenia definition incorporating weak muscle strength and/or poor physical function was related to prognosis, as was the regionally adapted version of EWGSOP. Although sarcopenia definitions were not developed based on prognosis, this is an important consideration for globally standardizing the sarcopenia framework.

Utility of four sarcopenia criteria for the prediction of falls-related hospitalization in older Australian women.

The aim of this prospective, population-based cohort study of 903 Caucasian-Australian women (mean age 79.9 ± 2.6years) was to compare the clinical utility of four sarcopenia definitions for the prediction of falls-related hospitalization over 9.5years. The four definitions were the United States Foundation for the National Institutes of Health (FNIH), the European Working Group on Sarcopenia in Older People (EWGSOP), and modified FNIH (AUS-POPF) and EWGSOP (AUS-POPE) definitions using Australian population-specific cut points (< 2 SD below the mean of young healthy Australian women). Components of sarcopenia including muscle strength, physical function, and appendicular lean mass (ALM) were quantified using hand grip strength, timed-up-and-go (TUG), and dual-energy X-ray absorptiometry (DXA), respectively. Incident 9.5-year falls-related hospitalization were captured by linked data. Baseline prevalence of sarcopenia according to FNIH (9.4%), EWGSOP (24.1%), AUS-POPF (12.0%), and AUS-POPE (10.7%) differed substantially. Sarcopenia did not increase the relative hazard ratio (HR) for falls-related hospitalization before or after adjustment for age (aHR): FNIH aHR 1.00 95%CI (0.69-1.47), EWGSOP aHR 1.20 95%CI (0.93-1.54), AUS-POPF aHR 0.96 95%CI (0.68-1.35), and AUS-POPE aHR 1.33 95%CI (0.94-1.88). When examining individual components of sarcopenia, only muscle strength and physical function but not ALM (adjusted for height2 or BMI) were associated with falls-related hospitalization. Current definitions of sarcopenia were not associated with falls-related hospitalization risk in this cohort of community-dwelling older Australian women. Finally, measures of muscle strength and physical function, but not ALM (measured by DXA) may help discriminate the risk of falls-related hospitalization.

Muscle Weakness and Physical Disability in Older Americans: Longitudinal Findings from the U.S. Health and Retirement Study.

Muscle weakness is an important indicator of disability, chronic disease and mortality. While we recently proposed sex/race specific grip strength cutpoints for clinical muscle weakness in a diverse, nationally representative sample of older Americans, the extent to which these cutpoints predict physical disability remains unknown. To examine whether sex/race specific muscle weakness cutpoints predict physical disability status in a nationally representative sample of Americans age 65+. We used data from the 2006-2010 Health and Retirement Study. Fully-adjusted, weighted multinomial logistic regression models were used to quantify the odds of experiencing the onset, progression or persistence of disability in activities of daily living (ADL) among weak versus non-weak individuals over a 2-year period. General community, nationally representative sample of older Americans. Population-based, community dwelling sample of older American adults aged 65-years+; 57 percent were women, 91% were White and the mean age was 75 years. Main Outcome(s) and Measure(s): The primary outcome of interest was disability dynamics, defined by changes in ADL status across at 2- year period. The primary exposure was clinical muscle weakness as defined by previously identified cutpoints. Hypotheses were formulated before analyses were conducted. In this nationally representative sample (n= 8,725), 44% of individuals were classified as weak at baseline. At follow-up, 55% remained independent with no change in their ADL status, 11% had an onset of disability and 4% progressed in their disability status. The odds of experiencing an onset of ADL disability was 54% higher among weak individuals compared those who were not weak at baseline (OR= 1.54, 95% CI= 1.54, 1.5, p<.0001); the odds of experiencing a progression in physical disability status was 2.16 times higher among those who were weak at baseline compared to non-weak individuals (OR= 2.16, 95% CI= 2.15, 2.16, p<.0001). This is the first study to use grip strength weakness cut-points to identify those who may be at greatest risk for experiencing physical disability in later life. Results underscore the importance of using population-specific cutpoints for clinical weakness in order to identify individuals at greatest risk for adverse health outcomes.

Calibration and Cross-Validation of the ActiGraph wGT3X+ Accelerometer for the Estimation of Physical Activity Intensity in Children with Intellectual Disabilities.

BackgroundValid objective measurement is integral to increasing our understanding of physical activity and sedentary behaviours. However, no population-specific cut points have been calibrated for children with intellectual disabilities. Therefore, this study aimed to calibrate and cross-validate the first population-specific accelerometer intensity cut points for children with intellectual disabilities.MethodsFifty children with intellectual disabilities were randomly assigned to the calibration (n = 36; boys = 28, 9.53±1.08yrs) or cross-validation (n = 14; boys = 9, 9.57±1.16yrs) group. Participants completed a semi-structured school-based activity session, which included various activities ranging from sedentary to vigorous intensity. Direct observation (SOFIT tool) was used to calibrate the ActiGraph wGT3X+, which participants wore on the right hip. Receiver Operating Characteristic curve analyses determined the optimal cut points for sedentary, moderate, and vigorous intensity activity for the vertical axis and vector magnitude. Classification agreement was investigated using sensitivity, specificity, total agreement, and Cohen’s kappa scores against the criterion measure of SOFIT.ResultsThe optimal (AUC = .87−.94) vertical axis cut points (cpm) were ≤507 (sedentary), 1008−2300 (moderate), and ≥2301 (vigorous), which demonstrated high sensitivity (81−88%) and specificity (81−85%). The optimal (AUC = .86−.92) vector magnitude cut points (cpm) of ≤1863 (sedentary), 2610−4214 (moderate), and ≥4215 (vigorous) demonstrated comparable, albeit marginally lower, accuracy than the vertical axis cut points (sensitivity = 80−86%; specificity = 77−82%). Classification agreement ranged from moderate to almost perfect (κ = .51−.85) with high sensitivity and specificity, and confirmed the trend that accuracy increased with intensity, and vertical axis cut points provide higher classification agreement than vector magnitude cut points.ConclusionsThis study provides the first valid methods of interpreting accelerometer output in children with intellectual disabilities. The calibrated physical activity cut points are notably higher than existing cut points, thus raising questions on the validity of previous low physical activity estimates in children with intellectual disabilities that were based on typically developing cut points.

Metabolic Profile of Sub-Saharan African Patients Presenting with First-ever-in-lifetime Stroke: Association with Insulin Resistance

To assess the pattern of metabolic profile associated with first stroke episode in a hospital setting in Cameroon. All patients admitted for first-ever-in-lifetime stroke over a 6-month period were eligible for inclusion in the study. The 84% participation rate yielded 57 of 68 patients between 16 and 85 years of age. Fifty-seven control subjects were selected to match patients included for age range, sex, and known hypertension and diabetes. We measured fasting serum glucose, insulin, and lipids in controls and in patients between days 3 and 7 after admission. Total cholesterol was comparable in patients and controls (172.6 ± 39.5 v 175.4 ± 49.7 mg/dL; P = .75), as were triglycerides (129.4 ± 56.1 v 122.4 ± 60.7 mg/dL; P = .53). high-density lipoprotein cholesterol (HDL-C) levels were lower in patients than in controls (37.4 ± 20.6 v 50.2 ± 18.0 mg/dL; P = .001), with comparable levels of low-density lipoprotein cholesterol (LDL-C; 109.4 ± 43.0 v 100.7 ± 48.8 mg/dL; P = .32). The LDL-C/HDL-C ratio was higher in patients compared to controls (4.0 ± 3.0 v 2.3 ± 1.7; P = .0001), as was the total cholesterol/HDL-C ratio (5.9 ± 3.5 v 3.9 ± 1.8; P = .0001). Compared to controls, stroke patients had higher fasting insulin levels (5.9 ± 5.4 v 2.3 ± 3.2 IU/mL; P < .001) and higher insulin resistance as measured by the homeostatic model assessment of insulin resistance (1.9 ± 2.2 v 0.7 ± 1.0; P = .001). Stroke is associated with markers of insulin resistance, low serum levels of HDL, and high total cholesterol/HDL ratio in this African population. Studies with a larger sample size and cohort designs are warranted to explore the causal pathways, persistence of these abnormalities, and population-specific cut points.

A modified mini nutritional assessment without BMI predicts nutritional status of community-living elderly in Taiwan.

The study was to determine whether a modified MNA (Mini Nutritional Assessment) which adopted population-specific anthropometric cut-points but without BMI could maintain its predicting ability in community-living elderly in Taiwan. Purposive sampling. Community-living elderly. Three hundred and one (138 male and 163 female) > 65-year-old outpatients seeking free annual health examination at an area hospital in central Taiwan. A structured questionnaire elicited personal data, lifestyle information and answers to the MNA. Laboratory results from health checkup provided the needed biochemical data. Each subject's nutritional status was assessed with the MNA in three versions: the original, the MNA-TI (with population-specific cut-points), and the MNA-TII (further eliminated the BMI question and redistributed its score to the MAC and CC questions). All three versions identified the same 0.7% elderly malnourished. The proportions predicted at risk of malnutrition were 16.6, 12.0 and 10% according to the original, MNA-TI and MNA-TII, respectively. Friedman Test and post hoc analysis indicated that the pattern predicted by the original MNA was different from that predicted by the two modified versions whereas the patterns predicted by the two modified versions were not different from each other. Adoption of population-specific anthropometric cut-points improves the predicting ability of the MNA in Taiwanese elderly, and the improved functionality is maintained in a version without BMI (but with adjusted MAC and CC scores). A MNA without BMI has greater applicability and can enhance professional efficiency of healthcare workers.

Population-specific anthropometric cut-points improve the functionality of the Mini Nutritional Assessment (MNA) in elderly Taiwanese.

The objective of this study was to determine the population-specific cut-points of body mass index (BMI), mid-arm circumference (MAC) and calf circumference (CC) for identifying subnormal nutritional status in elderly Taiwanese, and to evaluate the possibility of improving the functionality of the Mini Nutritional Assessment (MNA) by adopting these cut-points. This study analyzed data from 1583 men and 1307 women, 65 years or older, of a national survey. The survey involved in-home, face-to-face, interviews and anthropometric measurements. Results showed that based on the cumulative percentile curves, the fifth percentile values were: BMI, 17 kg/m2 for both men and women; MAC, 22.5 cm for men and 21 cm for women; and CC, 28 cm for men and 25 cm for women. Substitution of these population-specific cut-points for respective values in the MNA screen resulted in lowered proportions of elderly classified malnourished or at risk of malnutrition. The prevalence of malnutrition was reduced from 1.7% to 1.4% in men and from 2.4% to 1.5% in women. The proportions classified at risk of malnutrition were reduced from 10.1% to 8.9% for men and 16.8% to 12.8% for women. In conclusion, results suggest that the MNA is a valuable tool for geriatric nutritional risk assessment. However, in populations where significant differences exist in anthropometric measurements from the Caucasian populations, population-specific cut-points should be used.