Correlation of gut microbiota metabolite trimethylamine N-oxide with inflammatory levels and osteoporosis in patients with diabetic nephropathy

Figure 6 Correlation analysis of trimethylamine N-oxide and bone metabolism index levels in patients with diabetic nephropathy. Matrix scatter plot. r denotes the correlation coefficient. Polynomial fitting is used to explore potential nonlinear trends. The Pearson correlation coefficient r is applied to quantify the strength of the relationships between variables. Histograms on the diagonal illustrate the data distribution patterns. In the scatter plots, an upward-sloping trend line indicates a positive correlation, while a downward-sloping trend line indicates a negative correlation. Data points within the ellipse represent the main clustering region, while those outside the ellipse are considered outliers. ^aP < 0.05. TMAO: Trimethylamine N-oxide; H-BMD: Hip bone mineral density; L-BMD: Lumbar vertebrae bone mineral density; PINP: Procollagen type I N-terminal propeptide; β-CTX: Β-CrossLaps; ALP: Alkaline phosphatase.