To investigate the association between metabolic syndrome and perirenal fat stranding (PRFS), which is defined as linear or curvilinear soft tissue densities in the perirenal fat on computed tomography (CT).

Adults who had abdominal CT for health screening at a single institution between October 2022 and March 2023 were included retrospectively. Two radiologists assessed the extent of PRFS for each CT and graded it as absent, mild/moderate, and severe. Logistic regression analyses were used to investigate the associations between PRFS and metabolic syndrome-related factors, as well as age and gender.

Among 701 participants (mean age, 56.8 years ± 9.7; 336 women and 365 men), 87 (12.4%) had mild (n = 80) or moderate (n = 7) PRFS. None had severe PRFS. The presence of PRFS was independently associated with higher body mass index (odds ratio [OR], 2.561 and 9.842 for overweight and obese, respectively; p ≤ 0.001), elevated blood pressure with or without anti-hypertensive medication (OR, 2.232; p = 0.015), anti-diabetic medication (OR, 3.129; p < 0.001), and lipid-lowering medication (OR, 1.919; p = 0.019), older age (OR, 4.545 and 9.109 for 50–59 years and ≥ 60 years, respectively; p ≤ 0.002), and male gender (OR, 10.065; p < 0.001). Sixty three of 87 (72.4%) participants with PRFS had metabolic syndrome, while 265 of 614 (43.2%) participants without PRFS did (p < 0.001).

Incidental mild or moderate PRFS may be associated with the presence of metabolic syndrome or related disorders in otherwise healthy adults.