Abstract
Objectives The rising incidence of sarcopenia and osteoporosis, conditions closely linked to natural aging and frequently occurring together, may have varying impacts on prognosis. The purpose of this research is to use the NHANES database to explore how sarcopenia and osteoporosis may impact all-cause mortality and to assess whether there is an additive effect of these two conditions. Methods Individuals in this research were categorized into four groups depending on whether they had sarcopenia or osteoporosis. This study employed survival curves, Cox regression analyses, and restricted cubic splines, encompassing subgroup and sensitivity analyses, to explore the relationship between sarcopenia, osteoporosis, and all-cause mortality. Results Findings from the study revealed that participants suffering from both sarcopenia and osteoporosis exhibited the lowest survival rates. After adjusting for all potential factors, individuals diagnosed with sarcopenia alone had a 45% higher chance of experiencing all-cause mortality, while those with osteoporosis alone faced a 32% increased risk of all-cause mortality. Furthermore, individuals with both sarcopenia and osteoporosis had a 282% higher risk of all-cause mortality compared to those without either condition. The relative excess risk due to interaction (RERI) between sarcopenia and osteoporosis was 4.48 [95% CI: 1.98-8.08], the attributable proportion due to interaction (AP) was 0.66 [95% CI: 0.38-0.79], and the synergy index (S) was 4.4 [95% CI: 1.9-10.2]. Conclusions This indicates that the combination of sarcopenia and osteoporosis may have an additive effect on all-cause mortality, leading to an increased likelihood of death in individuals with both ailments. This study was to emphasize the importance of prevention over treatment for osteoporosis and sarcopenia to reduce the risk of death in this population.