Background: The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovas...

Heart Disease and Stroke Statistics—2020 Update: A Report From the American Heart Association

In this article, the 2010 European League against Rheumatism (EULAR) recommendations for the management of rheumatoid arthritis (RA) with synthetic and biological disease-modifying antirheumatic drugs (sDMARDs and bDMARDs, respectively) have been updated. The 2013 update has been developed by an international task force, which based its decisions mostly on evidence from three systematic literature reviews (one each on sDMARDs, including glucocorticoids, bDMARDs and safety aspects of DMARD therapy); treatment strategies were also covered by the searches. The evidence presented was discussed and summarised by the experts in the course of a consensus finding and voting process. Levels of evidence and grades of recommendations were derived and levels of agreement (strengths of recommendations) were determined. Fourteen recommendations were developed (instead of 15 in 2010). Some of the 2010 recommendations were deleted, and others were amended or split. The recommendations cover general aspects, such as attainment of remission or low disease activity using a treat-to-target approach, and the need for shared decision-making between rheumatologists and patients. The more specific items relate to starting DMARD therapy using a conventional sDMARD (csDMARD) strategy in combination with glucocorticoids, followed by the addition of a bDMARD or another csDMARD strategy (after stratification by presence or absence of adverse risk factors) if the treatment target is not reached within 6 months (or improvement not seen at

/pdf/eular-recommendations-for-the-management-of-rheumatoid-4fujp4paik.pdf

EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2016 update

Context Survival estimates help individualize goals of care for geriatric patients, but life tables fail to account for the great variability in survival. Physical performance measures, such as gait speed, might help account for variability, allowing clinicians to make more individualized estimates. Objective To evaluate the relationship between gait speed and survival. Design, Setting, and Participants Pooled analysis of 9 cohort studies (collected between 1986 and 2000), using individual data from 34 485 community-dwelling older adults aged 65 years or older with baseline gait speed data, followed up for 6 to 21 years. Participants were a mean (SD) age of 73.5 (5.9) years; 59.6%, women; and 79.8%, white; and had a mean (SD) gait speed of 0.92 (0.27) m/s. Main Outcome Measures Survival rates and life expectancy. Results There were 17 528 deaths; the overall 5-year survival rate was 84.8% (confidence interval [CI], 79.6%-88.8%) and 10-year survival rate was 59.7% (95% CI, 46.5%-70.6%). Gait speed was associated with survival in all studies (pooled hazard ratio per 0.1 m/s, 0.88; 95% CI, 0.87-0.90; P  Conclusion In this pooled analysis of individual data from 9 selected cohorts, gait speed was associated with survival in older adults.

https://jamanetwork.com/journals/jama/articlepdf/644554/joc05171_50_58.pdf

Gait speed and survival in older adults.

Background: The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascul...

Heart Disease and Stroke Statistics-2021 Update: A Report From the American Heart Association.

Sarcopenia: an undiagnosed condition in older adults. Current consensus definition: prevalence, etiology, and consequences. International working group on sarcopenia.

AIM: To investigate mechanical work, efficiency, and antagonist muscle co-activation with a view to better understand the cause of the elevated metabolic cost of walking (C(W)) in older adults. METHODS: Metabolic, mechanical and electromyographic measurements were made as healthy young (YOU; n = 12, age = 27 +/- 3 years) and older (OLD; n = 20, age = 74 +/- 3 years) men of equivalent body mass and leg length walked on a treadmill at four speeds (ranging from 0.83 to 1.67 m s(-1)). RESULTS: Net (above resting) C(W), determined by indirect calorimetry was 31% higher (average across speeds) in OLD (P < 0.05). The integrity of the passive pendulum like interchange of mechanical energies of the centre of mass (COM(B)), an energy-saving mechanism, was maintained in OLD. Furthermore, total mechanical work, determined from fluctuations in mechanical energy of COM(B) and of body segments relative to COM(B), was not significantly elevated in OLD. This resulted in a lower efficiency in OLD (-17%, P < 0.05). Co-activation, temporally quantified from electromyography recordings, was 31% higher in OLD for antagonist muscles of the thigh (P < 0.05). Thigh co-activation was moderately correlated with C(W) at three speeds (r = 0.38-0.52, P < 0.05). CONCLUSION: Healthy septuagenarians with no gait impairment have an elevated C(W) which is not explained by an elevation in whole body mechanical work. Increased antagonist muscle co-activation (possibly an adaptation to ensure adequate joint stability) may offer partial explanation of the elevated C(W).

Metabolic cost, mechanical work, and efficiency during walking in young and older men

Sarcopenia and muscle weakness are well-known consequences of aging. The aim of the present study was to ascertain whether a decrease in fascicle force (Ff) could be accounted for entirely by muscle atrophy. In vivo physiological cross-sectional area (PCSA) and specific force (Ff/PCSA) of the lateral head of the gastrocnemius (GL) muscle were assessed in a group of elderly men [EM, aged 73.8 yr (SD 3.5), height 173.4 cm (SD 4.4), weight 78.4 kg (SD 8.3); means (SD)] and for comparison in a group of young men [YM, aged 25.3 yr (SD 4.4), height 176.4 cm (SD 7.7), weight 79.1 kg (SD 11.9)]. GL muscle volume (Vol) and Achilles tendon moment arm length were evaluated using magnetic resonance imaging. Pennation angle and fiber fascicle length (Lf) were measured using B-mode ultrasonography during isometric maximum voluntary contraction of the plantar flexors. PCSA was estimated as Vol/Lf. GL Ff was calculated by dividing Achilles tendon force by the cosine of theta, during the interpolation of a supramaximal doublet, and accounting for antagonist activation level (assessed using EMG), Achilles tendon moment arm length, and the relative PCSA of the GL within the plantar flexor group. Voluntary activation of the plantar flexors was lower in the EM than in the YM (86 vs. 98%, respectively, P < 0.05). Compared with the YM, plantar flexor maximal voluntary contraction torque and Ff of the EM were lower by 47 and 40%, respectively (P < 0.01). Both Vol and PCSA were smaller in the EM by 28% (P < 0.01) and 16% (P < 0.05), respectively. Also, pennation angle was 12% smaller in the EM, whereas there was no significant difference in Lf between the YM and EM. After accounting for differences in agonists and antagonists activation, the Ff/PCSA of the EM was 30% lower than that of the YM (P < 0.01). These findings demonstrate that the loss of muscle strength with aging may be explained not only by a reduction in voluntary drive to the muscle, but mostly by a decrease in intrinsic muscle force. This phenomenon may possibly be due to a reduction in single-fiber specific tension.

Physiological cross sectional area and specific force are reduced in the gastrocnemius of elderly men

https://www.physiology.org/doi/pdf/10.1152/japplphysiol.01186.2004

In vivo physiological cross-sectional area and specific force are reduced in the gastrocnemius of elderly men

During their reproductive years the hormone levels in women fluctuate due to the menstrual cycle. The four hormonal markers of the menstrual cycle (oestrogen, progesterone, follicle stimulating hormone (FSH) and luteinising hormone (LH)) change continuously throughout the cycle. These fluctuations in female steroid hormones affect the autonomic nervous system and metabolic functions (Florini, 1987). Therefore certain physiological parameters and athletic performance could change along with the menstrual cycle phases (Becker et al. 1982). However, the influence of the menstrual cycle phase on exercise performance, particularly muscle strength, is unclear.

Sarwar et al. (1996) tested skeletal muscle strength, relaxation rate and fatiguability of the quadriceps during the menstrual cycle. They found no changes in these parameters for women taking oral contraceptives. For women not taking oral contraceptives, however, the quadriceps were stronger, more fatiguable and had a longer relaxation time at mid-cycle (day 12-18). Phillips et al. (1996) reported a higher adductor pollicis strength during the follicular phase than during the luteal phase, with a rapid decrease in strength around ovulation. They suggested that oestrogen has a strengthening action on skeletal muscle, although the underlying mechanism is not clear. Greeves et al. (1999), however, reported the highest quadriceps strength during the mid-luteal phase and found a positive relationship between strength and progesterone concentration. Several other studies have found no changes in skeletal muscle strength over the menstrual cycle (DiBrezzo et al. 1991; Quadango et al. 1991; Lebrun et al. 1995; Gur, 1997).

The main problem in the measurement of maximum voluntary strength is ensuring that the contraction truly reflects the maximum force-generating capacity of the muscle. Even well-motivated subjects may not always reach full neural activation of their muscles (Rutherford et al. 1986). The extent of neural activation can be evaluated by applying a superimposed electrical stimulus to the muscle during the performance of a maximal voluntary contraction (MVC). When comparing strength over a period of time, such as in menstrual cycle research, it is especially important to ensure maximal neural activation during each test.

A further problem encountered in research on the influence of the menstrual cycle on physical performance is the timing of the testing. It is difficult to predict the exact phases of the menstrual cycle and the concurrent reproductive hormone concentrations. Counting days from the onset of bleeding and basal body temperature (BBT) charting can be used to estimate the different phases of the menstrual cycle. These methods, however, only provide predictions, and serum hormone level measurements of at least oestrogen and progesterone are necessary to confirm the menstrual cycle phase.

Most of the studies on muscle strength during the menstrual cycle have either not measured hormone levels or relied upon the assumption that voluntary strength measurements were maximal. These problems have been addressed in this investigation of the influence of the menstrual cycle phase on skeletal muscle strength, fatigue and contractile properties.

https://physoc.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1469-7793.2001.0161m.x

The influence of menstrual cycle phase on skeletal muscle contractile characteristics in humans

Aim: To investigate whether sarcopenia was evenly distributed among the three components of the triceps surae (TS) muscle group.

Methods: Muscle volume (VOL), fibre fascicle length (Lf), pennation angle (θ) and physiological cross-sectional area (PCSA = VOL/Lf) were measured in vivo for the lateral (GL) and medial (GM) heads of the gastrocnemius muscles and for the soleus muscle (SOL), in 15 young males (YM, aged 25.3 ± 4.5 years) and 12 elderly males (EM aged 73.8 ± 4.4 years).

Results: In the EM, VOL of all three muscles was significantly smaller than in the YM; differences were: 27% for the GL (P < 0.01), 29% for the GM (P < 0.01) and 17% for the SOL (P < 0.05). In total, TS VOL was 22% smaller in EM than in YM (P < 0.01). In the EM, values of θ were significantly smaller than in the YM; by 15–18% for the GL, GM and SOL (P < 0.05). In the EM, Lf of the GM was 16% smaller than in the YM (P < 0.01); no significant differences were found in the other muscles. PCSA of the GL and GM were both found to be smaller in EM by 19% (P < 0.01) and 14.5% (P < 0.05), respectively. No difference was observed in the SOL PCSA between YM and EM. Interestingly, probably because of the prevalent contribution of the SOL to PCSA distribution of each muscle to the TS PCSA, the relative TS PCSA was not different between YM and EM. Furthermore, the Lf/muscle length ratio did not differ between YM and EM.

Conclusion: The present study shows that the relative PCSA composition of the TS is maintained with ageing and that the PCSA is scaled down harmonically with the decrease in muscle volume and fascicle length. Such observation suggests that the relative contribution of the components of the TS muscle to the total force developed by this muscle group is maintained with ageing.

Jeanette M. Thom

Papers

Metabolic cost, mechanical work, and efficiency during walking in young and older men

Physiological cross sectional area and specific force are reduced in the gastrocnemius of elderly men

In vivo physiological cross-sectional area and specific force are reduced in the gastrocnemius of elderly men

The influence of menstrual cycle phase on skeletal muscle contractile characteristics in humans

Changes in triceps surae muscle architecture with sarcopenia.