Objectives: Health problems in patients with heritable connective tissue disorders (HCTD) are diverse and complex and might lead to lower physical activity (PA) and physical fitness (PF). This study aimed to investigate the PA and PF of children with heritable connective tissue disorders (HCTD).Methods: PA was assessed using an accelerometer-based activity monitor (ActivPAL) and the mobility subscale of the Pediatric Evaluation of Disability Inventory Computer Adaptive Test (PEDI-CAT). PF was measured in terms of cardiovascular endurance using the Fitkids Treadmill Test (FTT); maximal hand grip strength, using hand grip dynamometry (HGD) as an indicator of muscle strength; and motor proficiency, using the Bruininks-Oseretsky Test of Motor Proficiency-2 (BOTMP-2).Results: A total of 56 children, with a median age of 11.6 (interquartile range [IQR], 8.8–15.8) years, diagnosed with Marfan syndrome (MFS), n = 37, Loeys-Dietz syndrome (LDS), n = 6, and genetically confirmed Ehlers-Danlos (EDS) syndromes, n = 13 (including classical EDS n = 10, vascular EDS n = 1, dermatosparaxis EDS n = 1, arthrochalasia EDS n = 1), participated. Regarding PA, children with HCTD were active for 4.5 (IQR 3.5–5.2) hours/day, spent 9.2 (IQR 7.6–10.4) hours/day sedentary, slept 11.2 (IQR 9.5–11.5) hours/day, and performed 8,351.7 (IQR 6,456.9–1,0484.6) steps/day. They scored below average (mean (standard deviation [SD]) z-score −1.4 (1.6)) on the PEDI-CAT mobility subscale. Regarding PF, children with HCTD scored well below average on the FFT (mean (SD) z-score −3.3 (3.2)) and below average on the HGD (mean (SD) z-score −1.1 (1.2)) compared to normative data. Contradictory, the BOTMP-2 score was classified as average (mean (SD) z-score.02 (.98)). Moderate positive correlations were found between PA and PF (r(39) = .378, p < .001). Moderately sized negative correlations were found between pain intensity and fatigue and time spent actively (r(35) = .408, p < .001 and r(24) = .395 p < .001, respectively).Conclusion: This study is the first to demonstrate reduced PA and PF in children with HCTD. PF was moderately positively correlated with PA and negatively correlated with pain intensity and fatigue. Reduced cardiovascular endurance, muscle strength, and deconditioning, combined with disorder-specific cardiovascular and musculoskeletal features, are hypothesized to be causal. Identifying the limitations in PA and PF provides a starting point for tailor-made interventions.
BACKGROUND: Survival of kidney transplant recipients (KTR) is low compared with the general population. Low muscle mass and muscle strength may contribute to lower survival, but practical measures of muscle status suitable for routine care have not been evaluated for their association with long-term survival and their relation with each other in a large cohort of KTR.METHODS: Data of outpatient KTR ≥ 1 year post-transplantation, included in the TransplantLines Biobank and Cohort Study (ClinicalTrials.gov Identifier: NCT03272841), were used. Muscle mass was determined as appendicular skeletal muscle mass indexed for height 2 (ASMI) through bio-electrical impedance analysis (BIA), and by 24-h urinary creatinine excretion rate indexed for height 2 (CERI). Muscle strength was determined by hand grip strength indexed for height 2 (HGSI). Secondary analyses were performed using parameters not indexed for height 2. Cox proportional hazards models were used to investigate the associations between muscle mass and muscle strength and all-cause mortality, both in univariable and multivariable models with adjustment for potential confounders, including age, sex, body mass index (BMI), estimated glomerular filtration rate (eGFR) and proteinuria. RESULTS: We included 741 KTR (62% male, age 55 ± 13 years, BMI 27.3 ± 4.6 kg/m 2), of which 62 (8%) died during a median [interquartile range] follow-up of 3.0 [2.3-5.7] years. Compared with patients who survived, patients who died had similar ASMI (7.0 ± 1.0 vs. 7.0 ± 1.0 kg/m 2; P = 0.57), lower CERI (4.2 ± 1.1 vs. 3.5 ± 0.9 mmol/24 h/m 2; P < 0.001) and lower HGSI (12.6 ± 3.3 vs. 10.4 ± 2.8 kg/m 2; P < 0.001). We observed no association between ASMI and all-cause mortality (HR 0.93 per SD increase; 95% confidence interval [CI] [0.72, 1.19]; P = 0.54), whereas CERI and HGSI were significantly associated with mortality, independent of potential confounders (HR 0.57 per SD increase; 95% CI [0.44, 0.81]; P = 0.002 and HR 0.47 per SD increase; 95% CI [0.33, 0.68]; P < 0.001, respectively), and associations of CERI and HGSI with mortality remained independent of each other (HR 0.68 per SD increase; 95% CI [0.47, 0.98]; P = 0.04 and HR 0.53 per SD increase; 95% CI [0.36, 0.76]; P = 0.001, respectively). Similar associations were found for unindexed parameters. CONCLUSIONS: Higher muscle mass assessed by creatinine excretion rate and higher muscle strength assessed by hand grip strength are complementary in their association with lower risk of all-cause mortality in KTR. Muscle mass assessed by BIA is not associated with mortality. Routine assessment using both 24-h urine samples and hand grip strength is recommended, to potentially target interdisciplinary interventions for KTR at risk for poor survival to improve muscle status.
Abstract Background: 30 to 60% of the acute hospitalized older adults experience functional decline after hospitalization. The first signs of functional decline after discharge can often be observed in the inability to perform mobility tasks, such as raising from a chair or walking. Information how mobility develops over time is scarce. Insight in the course of mobility is needed to prevent and decrease mobility limitations. Objectives: The objectives of this study were to determine (i) the course of mobility of acute hospitalized older adults and (ii) the association between muscle strength and the course of mobility over time controlled for influencing factors. Methods: In a multicenter, prospective, observational cohort study, measurements were taken at admission, discharge, one- and three months post-discharge. Mobility was assessed by the De Morton Mobility Index (DEMMI) and muscle strength by the JAMAR. The longitudinal association between muscle strength and mobility was analysed with a Linear Mixed Model and controlled for potential confounders. Results: 391 older adults were included in the analytic sample with a mean (SD) age of 79.6 (6.7) years. Mobility improved significantly from admission up to three months post-discharge but did not reach normative levels. Muscle strength was associated with the course of mobility (beta=0.64; p<0.01), even after controlling for factors as age, cognitive impairment, fear of falling and depressive symptoms (beta=0.35; p<0.01). Conclusion: Muscle strength is longitudinally associated with mobility. Interventions to improve mobility including muscle strength are warranted, in acute hospitalized older adults.