Dietary total antioxidant capacity is associated with lower disease severity and inflammatory and oxidative stress biomarkers in patients with knee osteoarthritis

Table 1 General characteristics of patients with knee osteoarthritis across quartiles of dietary TAC^a

Variables	Quartiles of dietary TAC^b				P^c
Variables	Q1 (n = 40)	Q2 (n = 40)	Q3 (n = 40)	Q4 (n = 40)	P^c
Females, n (%)	22 (55.0)	24 (60.0)	19 (47.5)	24 (60.0)	0.638
Age (yr)	57.4 ± 9.6	57.9 ± 7.3	56.6 ± 8.4	57.1 ± 7.4	0.916
Weight (kg)	81.5 ± 13.6	82.0 ± 12.9	83.4 ± 11.8	81.3 ± 13.1	0.885
BMI (kg/m²⁾	27.7 ± 3.0	28.1 ± 3.1	27.6 ± 2.8	28.2 ± 3.3	0.725
Obesity, n (%)^d	9 (72.5)	32 (80.0)	30 (75.0)	31 (77.5)	0.875
Vitamin D supplement use, n (%)	20 (50.0)	17 (42.5)	21 (52.5)	16 (40.0)	0.635
Calcium supplement use, n (%)	19 (47.5)	14 (35.0)	15 (37.5)	11 (27.5)	0.319
Current smoker, n (%)	9 (22.5)	7 (17.5)	9 ( 22.5)	8 (20.0)	0.936
Physical activity (MET-h/week)	29.0 ± 6.6	28.5 ± 6.8	30.1 ± 7.3	29.1 ± 6.2	0.760
Knee osteoarthritis duration (yr)	7.2 ± 4.8	6.7 ± 2.6	7.1 ± 2.7	6.0 ± 3.2	0.442

TAC, total antioxidant capacity and BMI, body mass index
^aAll values are expressed as means ± standard deviations unless indicated
^bQuartile cut points of dietary TAC are as follows: first quartile, < 8.02; second quartile, 8.02–11.39; third quartile, 11.40–15.43; and fourth quartile, ≥ 15.44
^cResulted from one-way ANOVA for continuous variables and Chi-square test for categorical variable
^dObesity was defined as BMI ≥ 25 kg/m²
P < 0.05 was considered significant

ISSN: 2072-1315