Table 2.

Stepwise linear regression analysis of baseline levels of kynurenines versus corresponding yearly change in clinical parameters (ΔeGFR and percent change of HtTKV) in ADPKD patients

	Children and young adults with ADPKD
Baseline 3-OH KYN	beta = 0.324, p = 0.046	Yearly change in eGFR
Baseline PA	beta = − 0.345, p = 0.013	Yearly % change in HtTKV
	Adults with ADPKD
Baseline AA	beta = 0.427, p = 0.012	Yearly % change in HtTKV
Baseline 3-OH KYN	beta = 0.550, p = 0.006	Yearly % change in HtTKV

Samples collected at the initiation of the pravastatin interventional trial in children and young adults (N = 64) and at invitation of the HALT-PKD trial (N = 80) were used for analysis. Yearly absolute change (delta) in eGFR was calculated as the difference between the levels at 4 years as compared to the baseline in individual patients, whereas for yearly percent change in HtTKV we normalized the yearly change Δ to the corresponding baseline value and so calculated the percent change in the respective patient. Adjustments for gender, age, race, SBP, BMI and study group were made. p < 0.0056 is considered significant (after Bonferroni correction)

3-OH KYN 3-hydroxykynurenine; AA anthranilic acid; PA picolinic acid