Incidence of sarcopenia in elderly patients undergoing CR - an observational cohort study

Introduction: Sarcopenia is characterized by progressive and generalized loss of skeletal muscle mass and strength. Patients with sarcopenia have a higher risk of frailty and hence poor health outcomes including falls, hospitalization and mortality. This ongoing pre-study aims to assess the incidence of sarcopenia in the „PRECOVERY“ cohort and the impact of an inpatient cardiac rehabilitation (CR) three months post completion.

Methods: Observational cohort pre-study of the ongoing randomized, controlled, multicenter, outcome assessor-blinded prehabilitation-study „PRECOVERY“. Recruitment is carried out in four inpatient rehabilitation clinics. Inclusion criteria: Patients ≥ 75 years who receive inpatient CR after cardiac surgery or valve intervention. We use the SARC-F questionnaire to identify probable sarcopenic patients. Additional assessments at baseline are: Katz-Index, hand grip strength, Short Physical Performance Battery (SPPB) and six-minute-walk test (6MWT). Three months after CR-completion the SARC-F questionnaire will be repeated by telephone. This interim analysis focuses on the correlation between sarcopenia and six-minute-walk distance (6MWD), SPPB and hand grip strength.

Results: A sample of 51 patients (80.2 ± 4.7 years; m: 66.7 %) completed the baseline assessments. Main indication for CR were: coronary artery bypass surgery (31.6 %), valve surgery (19.3 %) and valve intervention (17.5 %). Of the cohort 31.4 % reported living independently at home and 23.5 % receiving some degree of nursing assistance. At baseline the mean SARC-F questionnaire- Score was 2.7 ± 2.1 and 35.4% of the cohort were diagnosed having sarcopenia. Further results are: Katz-Index 5.7 ± 0.8 and 19.6 % were defined as frail; hand grip strength 24.5 ± 9.4kg; SPPB-Score 7.2 ± 3.5 and 6MWD 287.7 ± 136.9 m. The calculation of the eta coefficient with one-way ANOVA revealed a significant correlation between sarcopenia measured by the SARC-F questionnaire and the 6MWD (Eta = 0.538; p < 0.001), SPPB-Score (Eta = 0.628; p < 0.001) and hand grip strength (Eta = 0.504; p < 0.001).

Conclusion: The incidence of sarcopenia in older patients entering CR after cardiac surgery or valve intervention is high (35.4 %). This is important since the diagnosis of sarcopenia in these patients correlates significantly with functional tests. The results indicate that this group of patients could benefit from prehabilitation for physical and psychological stabilization prior to cardiac surgery or intervention, thereby reducing the negative effects of sarcopenia.

Keywords: cardiac surgery – valve intervention – sarcopenia – cardiac rehabilitation