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Objectives
Declining muscle mass and function are hallmarks of the aging process. The preservation of muscle trophism may protect against various negative health outcomes. Age- and sex-specific curves of muscle mass, strength, and function, using data from a large sample of community-dwelling people, are necessary.Material and methods
Two surveys (Longevity Check-up and Very Important Protein [VIP]), conducted during EXPO 2015 in Milan, consisted of a population assessment aimed at evaluating the prevalence of specific health metrics in subjects outside of a research setting (n = 3206), with a special focus on muscle mass, strength, and function. Muscle mass was estimated by using mid-arm muscle circumference (MAMC) and calf circumference of the dominant side. Muscle strength and function were assessed through handgrip strength testing and repeated chair stand test, respectively.Results
The mean age of 3206 participants in the Longevity Check-up and VIP surveys was 51.9 years (SD 15.6, range 18–98 years), and 1694 (52.8%) were women. Cross-sectional inspection suggests that both calf circumference and MAMC decline nonlinearly with age and the rate of decline varies by gender. These measures are stable until 50 years and then begin to decrease slightly with age, with the effect being more evident in men than in women. The main effect of the age category was observed in muscle strength and physical performance parameters. Muscle strength declined significantly after 45 years of age, both in men and women (P < .001). The muscle quality of the upper extremities, defined as handgrip strength divided by MAMC, declined significantly with aging, as well (P < .001). The time to complete the chair stand test was similar from 18 years to 40 to 44 years, and then a linear decline in performing the test across age groups was observed, with an increased time of more than 3 seconds, both in men and women (P < .001).Conclusions
Muscle mass and strength curves may be used to extract reference values for subsequent use in research as well as in the clinical setting. In particular, the analyses of trajectories of muscle parameters may help identify cutoffs for the estimation of risk of adverse events. 相似文献The current article provides a brief overview of the criteria for defining disease control in acromegaly.
MethodsThis was a retrospective, narrative review of previously published evidence chosen at the author’s discretion along with an illustrative case study from Latin America.
Findings and ConclusionsIn the strictest sense, “cure” in acromegaly is defined as complete restoration of normal pulsatile growth hormone secretion, although this is rarely achieved. Rather than “cure”, as such, it is more appropriate to refer to disease control and remission, which is defined mainly in terms of specific biochemical targets (for growth hormone and insulin-like growth factor-1) that predict or correlate with symptoms, comorbidities and mortality. However, optimal management of acromegaly goes beyond biochemical control to include control of tumour growth (which may be independent of biochemical control) and comprehensive management of the symptoms and comorbidities typically associated with the disease, as these may not be adequately managed with acromegaly-specific therapy alone.
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