Association Between Serum Alkaline Phosphatase Levels and Sarcopenia in US Adults: A Cross-sectional Study

Serum alkaline phosphatase (ALP) is an important biomarker associated with various physiological processes and diseases. Although alkaline phosphatase's impact on health has been extensively studied, its specific relationship with sarcopenia remains unclear.

Cross-sectional study.

This study is based on the National Health and Nutrition Examination Survey (NHANES) data from 2011 to 2018, including 6098 eligible participants aged 20 years and older.

Serum ALP was obtained through biochemical tests, and sarcopenia was assessed by adjusting appendicular skeletal muscle mass for body mass index (BMI). The study employed weighted logistic regression, restricted cubic splines, stratified analysis, and interaction tests to analyze the relationship between the two, and conducted sensitivity analyses to examine the stability of the associations. Further stratification was performed based on vigorous recreational activity.

Multivariate logistic regression analysis showed that after adjusting for other confounding factors, ALP levels were significantly positively correlated with sarcopenia. Compared with participants in the lowest quartile of ALP, those in the highest quartile had an increased risk of sarcopenia by 1.96 times (odds ratio 1.96, 95% CI 1.19-3.23, P < .01). This association was more pronounced in individuals with BMI ≥25. Restricted cubic spline analysis revealed a linear relationship between the 2 variables. Notably, individuals lacking in vigorous recreational activity may have a higher prevalence of sarcopenia.

Our study found that elevated serum ALP levels are significantly associated with an increased risk of sarcopenia. Monitoring serum ALP levels and engaging in moderate physical activity may be effective strategies to reduce the risk of sarcopenia.