Risco de sarcopenia e fatores associados em idosos durante o enfrentamento da pandemia por coronavírus: Rede Remobilize

Abstract

The decline in muscle mass (MM), muscle strength (MS) and muscle quality (MQ) associated with aging predispose to the risk of sarcopenia (RS). Behavioral and environmental factors also drive the dynamic precursor network of sarcopenia. This muscle disorder is associated with adverse outcomes, such as reduced mobility in living spaces (MLS) and functional disability. With the outbreak of the new coronavirus, protective measures such as social distancing, were recommended. However, restriction at home strengthens a vicious cycle harmful to MM and muscle function in the aged, consisting of long periods of sedentary behavior, physical inactivity and changes in eating habits, enhancing the predisposition to RS. In this context, the general objective of the thesis was to investigate the prevalence of RS and associated factors in community-dwelling older Brazilian and the MLS trajectories of those with and without RS during the pandemic, as well as to verify a more accessible proposal for the diagnosis of sarcopenia. Study 1 had the specific objective of estimating the prevalence of RS and investigating the associated factors during the pandemic in older Brazilian. Based on data collected through online questionnaires by the Remobilize Network (May to July 2020), the sample (n=1482) was composed of community-dwelling older Brazilian, without distinction of race and/or social class, excluding those bedridden or institutionalized. RS was assessed using the SARC-F questionnaire (cutoff point of 4 pts or more), MLS using the Life-Space Assessment, the presence of functional limitation using the BOMFAQ questionnaire (Brazilian OARS Multidimensional Functional Assessment Questionnaire) and walking as an exercise, utility and total by the IPEQ (Incidental and Planned Exercise Questionnaire, converted into min/wk). Data on the presence of pain and time sitting at home ([ST], in hours/day) were also recorded. The prevalence of RS found was 17.1%, and the logistic regression showed a significant association between RS and moderate to severe functional limitation, comorbidities, pain, total walking and a “dose-response” effect with the number of hours in the ST. Study 2 had the specific objective of identifying and analyzing MLS trajectories in a cohort of older with (GRS) and without RS (GNRS) and comparing the clinical-functional and behavioral aspects between subgroups with different trajectories. This is a longitudinal study with follow-up of four waves over the course of the pandemic (baseline, 3, 9 and 16 months). The longitudinal multilevel model was adopted to quantify the variance between individuals and between times in the MLS trajectory in each group. MLS was lower in the GRS compared to the GNRS group. In the GRS, advanced age, being inactive, and women with moderate to severe functional limitations were significantly associated with variability in the MLS trajectory model. In the GNRS, there was a significant effect on the interaction of female sex and comorbidities; age group 70-79 years and insufficiently active; 70-79 years and 5-7 hours of ST; total walk and ST; and ST and pain. Study 3 aimed to compare the definitions of sarcopenia proposed by the European Working Group on Sarcopenia in Older People (EWGSOP2) and by the Sarcopenia Definition and Outcomes Consortium (SDOC) concerning muscle performance and muscle quality indices (MQI) in the lower limbs in with (GS) and without sarcopenia (GNS). This is a cross-sectional study with women (≥ 65 years), community residents, sedentary and with muscle function deficit. The diagnosis of sarcopenia was confirmed using EWGSOP2 (reduced handgrip strength and MM) and SDOC (reduced handgrip strength and gait speed). An isokinetic dynamometer was used to assess peak torque (PT), maximum work (MW) and muscle power (POW) of the lower limbs. MQI was expressed by the muscle performance ratio (PT, MW and POW) and MM adjusted by the body mass index (BMI) and MM of the right lower limb. Ninety-six olders were included, in both definitions the GS (SDOC n=37 and EWGSOP2 n=48) presented significantly lower PT, MW, POW and MQI adjusted for BMI regarding the GNS. Sarcopenia (SDOC) was significantly associated with PT, MW and POW and all MQI variables. According to EWGSOP2, only MW maintained a significant association with sarcopenia after adjusting for sociodemographic factors. The SDOC definition of sarcopenia was significantly associated with the MQ variables studied, encouraging its indication and use in clinical practice. Thus, the thesis findings show that MLS trajectories in the GRS and GNRS groups were distinguished throughout the pandemic. Identifying associated risk and protective factors makes it possible to develop preventive actions for RS and its progression. In addition, efforts should be directed toward detecting sarcopenia in the early stages; using less complex instruments (SDOC) can promote adherence in clinical practice.