Fatigue and the prediction of negative health outcomes: A systematic review with meta-analysis.

INTRODUCTION: Fatigue is a common complaint among older adults. Evidence grows that fatigue is linked to several negative health outcomes. A general overview of fatigue and its relationship with negative health outcomes still lacks in the existing literature. This brings complications for healthcare professionals and researchers to identify fatigue-related health risks. Therefore, this study gives an overview of the prospective predictive value of the main negative health outcomes for fatigue in community-dwelling older adults. METHODS: PubMed, Web of Knowledge and PsycINFO were systematically screened for prospective studies regarding the relationship between fatigue and negative health outcomes resulting in 4595 articles (last search 5th March 2020). Meta-analyses were conducted in RevMan using Odds ratios (ORs), Hazard ratios (HRs) and relative risk ratios (RR) that were extracted from the included studies. Subgroup-analyses were performed based on (1) gender (male/female), (2) length of follow-up and (3) fatigue level (low, medium and high). RESULTS: In total, thirty articles were included for this systematic review and meta-analysis encompassing 152 711 participants (age range 40-98 years), providing information on the relationship between fatigue and health outcomes. The results showed that fatigue is related to an increased risk for the occurrence of all studied health outcomes (range OR 1.299-3.094; HR/RR 1.038-1.471); for example, mortality OR 2.14 [1.74-2.63]; HR/RR 1.44 [1.28-1.62]), the development of disabilities in basic activities of daily living (OR 3.22 [2.05-5.38]), or the occurrence of physical decline (OR 1.42 [1.29-1.57]). CONCLUSION: Overall fatigue increases the risk for developing negative health outcomes. The analyses presented in this study show that fatigue related physical decline occurs earlier than hospitalization, diseases and mortality, suggesting the importance of early interventions.

The operationalization of fatigue in frailty scales: a systematic review.

PURPOSE: To identify the different fatigue items in existing frailty scales. METHODS: PubMed, Web of Knowledge and PsycINFO were systematically screened for frailty scales. 133 articles were included, describing 158 frailty scales. Fatigue items were extracted and categorized in 4 fatigue constructs: "mood state related tiredness", "general feeling of tiredness", "activity based feeling of tiredness" and "resistance to physical tiredness". RESULTS: 120 fatigue items were identified, of which 100 belonged to the construct "general feeling of tiredness" and only 9 to the construct "resistance to physical tiredness". 49,4% of the frailty scales included at least 1 fatigue item, representing 15 ±â€¯9,3% of all items in these scales. Fatigue items have a significantly higher weight in single domain (dominantly physical frailty scales) versus multi domain frailty scales (21 ±â€¯3.2 versus 10.6 ±â€¯9.8%, p=<0,05). CONCLUSION: Fatigue is prominently represented in frailty scales, covering a great diversity in fatigue constructs and underlying pathophysiological mechanisms by which fatigue relates to frailty. Although fatigue items were more prevalent and had a higher weight in physical frailty scales, the operationalization of fatigue leaned more towards psychological constructs. This review can be used as a reference for choosing a suitable frailty scale depending on the type of fatigue of interest.

Evaluation of appendicular lean mass using bio impedance in persons aged 80+: A new equation based on the BUTTERFLY-study.

BACKGROUND: To date, the accuracy of bio-impedance (BIA) to assess body composition & sarcopenia in persons aged 80 and over remains unclear. OBJECTIVE: We aimed to evaluate the agreement between dual energy X-ray absorptiometry (DXA) and BIA equations to determine lean mass, as well as their suitability to identify sarcopenia. DESIGN: 174 community dwelling well-functioning persons (83 women, 91 men) aged 80 and over were included. Appendicular lean mass (ALM) was predicted using BIA-based equations available in literature, and compared to DXA outcomes. Through cross-validation and stepwise multiple linear regression, a new ALM-formula was generated suitable for this population. RESULTS: Literature-based BIA equations systematically overestimated ALM. The new prediction formula that we propose for the 80+ is: ALM = 0,827+(0,19*Impedance Index)+(2,101*Sex)+(0,079*Weight); R2 = 0,888; SEE = 1,450 kg. Sarcopenia classification based on our new BIA equation for ALM showed better agreement with DXA (k ≥ 0,454) compared to literature-based BIA equations (k < 0,368). CONCLUSIONS: Despite the high correlation between both methods, literature-based BIA equations consistently overestimate ALM compared to DXA in persons aged 80 and over. We proposed a new equation for ALM, reaching higher agreement with DXA and thus improving the accuracy of BIA for this specific age group.

Three-dimensional kinematics of the cervical spine using an electromagnetic tracking device. Differences between healthy subjects and subjects with non-specific neck pain and the effect of age.

BACKGROUND: A cross-sectional observational study of three-dimensional cervical kinematics in 35 non-specific neck pain patients and 100 asymptomatic controls. To compare qualitative and quantitative aspects of cervical kinematics between healthy subjects and subjects with non-specific neck pain and to determine the effect of age on cervical kinematics in healthy subjects. METHODS: Three-dimensional kinematics of active lateral bending and flexion-extension of 35 patients and 100 controls were registered by means of an electromagnetic tracking system. The means of several kinematic parameters were compared using t-tests. In addition, we assessed the age-dependency of the three-dimensional kinematic parameters by stratifying the 100 control subjects in 6 age categories. FINDINGS: Comparison of the patient group with the control group reveals no statistically significant differences in qualitative and quantitative parameters. Analysis of the effect of age showed that the range of motion decreases significantly (p < 0.01) with increasing age. In lateral bending, the ratio between axial rotation and lateral bending increases significantly (p < 0.01) among older subjects. Differences in acceleration, jerk and polynomial fit are seen between the age categories, but are not significant. INTERPRETATION: This study demonstrates no significant differences in kinematic parameters between healthy subjects and subjects with non-specific neck pain. Healthy subjects in higher age categories demonstrate higher ratios of coupled movements and lower ranges of motion. Future research should focus on classifying patients with non-specific neck pain in order to gain a better insight on possible subgroup specific differences in kinematics. More studies on this subject are warranted. LEVEL OF EVIDENCE: 4.

Evidence of increased axillary blood flow velocity without increased handgrip strength and endurance in persons with a fibromuscular axillary arch.

BACKGROUND: The purpose of this in vivo study was to compare axillary artery blood flow velocity, and maximal handgrip strength and endurance performance in young subjects with and without an axillary arch (AA). MATERIALS AND METHODS: One hundred and fifty-six young adults were screened for the presence of an AA on their dominant arm side. After physical examination subjects were checked using diagnostic echography for the presence of an AA. Sixteen subjects with an AA and 15 without an AA had their axillary artery peak systolic velocity quantified in 3 different arm positions using Doppler ultrasound. Maximal handgrip strength and endurance performance was quantified in the same positions using a functional rehabilitation system. RESULTS: Mean peak systolic velocity was significantly higher in the AA group compared to controls in abduction/external rotation of the arm during muscle relaxation (p = 0.003) and contraction (p = 0.01). No significant differences between groups were found for maximal handgrip strength and endurance performance. CONCLUSIONS: This study provides evidence for a transient axillary artery compression by the AA in a throwing position. This is not reinforced by additional contraction of the shoulder muscles along with the AA. Axillary artery compression does not influence maximal handgrip strength and endurance performance in symptom-free young adults.

Direct relationship of body mass index and waist circumference with body tissue distribution in elderly persons.

OBJECTIVES: To explore the relationship of BMI and WC with muscle/adipose tissue mass ratios and with trunk adipose tissue distribution, based on an anatomical 5-compartment model, by dissection of cadavers of elderly persons. DESIGN: Cross-sectional explorative study. SETTING: Brussels Cadaver Analysis Study. PARTICIPANTS: Cadavers of twenty-nine white Caucasian elderly persons (17 females and 12 males, aged 78.1±6.9 years). MEASUREMENTS: Whole body and trunk composition were determined at the anatomical tissue-system level by direct dissection. RESULTS: BMI and WC were significantly and positively related to absolute tissue masses in both sexes. Muscle tissue mass, adipose tissue mass and trunk internal adipose tissue mass correlated better with BMI (r-values between 0.68 and 0.89) than with WC (r-values between 0.49 and 0.71). BMI was significantly and inversely related with various muscle/adipose tissue ratios in both sexes (r-values between -0.54 and -0.68). WC correlated with muscle/adipose tissue ratios in females only (r-values between -0.55 and -0.64). BMI was also significantly related to trunk adipose tissue distribution in elderly females, but not in males. When comparing individual tissue proportions within and between adjacent BMI-classifications or WC categories, body composition varied considerably. CONCLUSION: Our results show that BMI and WC are significantly related with adipose tissue mass and with several ratios of muscle to adipose tissue in elderly subjects. However, cautious clinical interpretation is warranted since important differences in tissue mass proportions were found in subjects with similar BMI and/or WC values.

Quality control of 157 whole body adiposity prediction formulae in age and activity matched men.

AIM AND METHODS: The physiological and clinical importance of body composition is part of public health, nutrition and Sports medicine. The most popular field method for estimating total body adiposity remains anthropometry separately or in formulae. The aim of this study was to verify the suitability of an absolute maximum out of more than 600 existing anthropometry equations estimating % adipose tissue (AT) in a cross validation with dual energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA) and hydrodensitometry (HD) on 74 British male subjects (mean age 34.4±14.1) with different lifestyles corresponding to a maximum of populations the original formula was developed for. RESULTS: Pearson correlation coefficients, paired sample t-test and Bland and Altman plots where used for analyses. From the tested formulae, 19 correlated well (r≥0.70) and showed no significant difference (p>0.05) with BIA, 15 with DXA and only 12 with HD. The results show a better match of the predicted % AT by anthropometric equations with BIA then with DXA or HD. CONCLUSION: All results and conditions considered, this study suggest not to use HD nor anthropometric formulae to assess % AT in men for an individual estimation.

Hazards of hydrodensitometry.

The limitations of the two-component model of body composition have been investigated extensively in the past resulting in a clear message of violation of basic assumptions underlying its use. This strong message may or may not be appropriate, since hydrodensitometry is still used, in particular in sports sciences. The combination of novel information with previously described indicators should allow to confirm or reject the pretended violation of basic assumptions underlying the use of hydrodensitometry. Water content of adipose tissue (AT) and of AT free mass as opposed to fat and fat free mass, and bone density of separate bones was obtained from the Brussels Cadaver Analysis Study collection. Analysis of different studies indicated anomalies up to -12% fat but also suggests that the borderline between chemical and morphological interpretations becomes vague and the ad hoc terminology does not reflect reality. Predicted % body fat using different methods on the same individual ranges between 9.6% up to 21% of AT. Total body water of separate tissues suggests intra-and intervariability within tissues. Whole skeleton density and the separate bone density cannot support the two-component constancy (1.164 g/mL to 1.570 g/mL).

Direct measurement of tibial cortical bone surface area.

Cortical bone surface area estimation is generally performed by analysis of medical images but its accuracy has not yet been verified by direct bone measurements. This study was performed to evaluate the reproducibility of direct ex vivo estimations of cross sectional tibial cortical bone surface area. Ten tibiae were evaluated by two observers using direct 3D-digitization at 38 and 66% of total tibial length using a 'critical' and a 'general' criterion for differentiation between cortical and cancellous bone. The results of the analysis using the more severe 'critical' differentiation criterion yielded high intra and interobserver agreement. Mean intraobserver reliability was demonstrated by R = 0.98 (Spearman rank correlation between 0.98 and 0.97; P < 0.01) and inter observer reliability by R = 0.91 (Spearman rank correlation between 0.95 and 0.88; P < 0.01). When using strict criteria to differentiate between cortical and cancellous bone, intra and interobserver reliability of the presented method of direct cortical bone surface area estimation is very high. The results indicate that cross-sectional cortical bone surface estimation by direct 3D-digitization can serve as a gold standard for validation of other estimations methods.

Body mass index as a measure of bone mass.

AIM: BMI is an indicator of body composition (BC) and adiposity in particular. This status is the result of good correlations with indirect (e.g. predictive) two- and three-component models predicting body fat. Aim of the study is to measure the direct relation of BMI with total and segmental BC, e.g. of skin, muscle, bone, viscera and adipose tissue. METHODS: BC constituents of 29 white elderly persons (17 females and 12 males, aged 78.1+/-6.9 years) were determined by direct dissection. Correlations and stepwise linear regression analysis with BMI (dependent variable) and all BC constituents (independent variables) were calculated. RESULTS: All tissues dissected indicated a too high unexplained variance except for bone that accounted for 84% of BMI variance in females and 61% in males (P<0.001). No other constituents improved the prediction. CONCLUSION: The BMI cannot be an appropriate adiposity index. The high proportion of unexplained variance between BMI and direct BC constituents limit its use as a whole body and as a segmental BC index. The BMI could be an index for Bone Mass instead.

[Left-right asymmetries and other common anatomical variants of temporomandibular articular surfaces]. / Links-rechts asymmetriën en andere anatomische varianten van de temporomandibulaire gewrichtsvlakken.

The purpose of the study was to investigate left-right asymmetries and other anatomical variants of temporomandibular articular surfaces. Digital photography and macroscopic observation were used to gather information about the shape, size, orientation and degeneration of temporomandibular articular surfaces of 100 skull bases and 100 mandibles. Left-right asymmetries in shape, size, orientation and degeneration were found in 39.5, 26, 16 and 31.5% of the mandibular surfaces respectively. The glenoid fossae showed left-right asymmetries in size, orientation and degeneration in 4.1 and 22.5% of cases respectively. Left-right asymmetries in orientation were found in 24% of the articular eminences. Anatomical variants of the mandibular articular surfaces were found as differences in shape: the majority had horizontal oblong outlines and rounded frontal outlines; one fifth showed pear-shaped horizontal outlines and flat or ridge-shaped frontal outlines. The important incidence of left-right asymmetries and anatomical variants of temporomandibular articular surfaces must be considered when observing and treating temporomandibular dysfunction. It can be expected that these asymmetries and anatomical variants may have arthrokinematic consequences for treatment of temporomandibular dysfunction.