3. Results
3.1. Demographic and Clinical Features: The study included 29 (50.9%) adolescent patients with OCD and 28 (49.1%) adolescent healthy controls. No significant difference was found between the groups in terms of age (p = 0.179) or sex (p = 0.198) . At least one psychiatric disorder was found in a 1st or 2nd degree relative of 17 (58.6%) children in the OCD group and 2 (3.1%) children in the control group (p = 0.000) . The clinical and demographic features of all cases are shown in Table 1.
3.2. C-YOCBS Features and Scores of the Patient Group: All of the patients had both obsessions and compulsions. Washing/cleaning (82.8%) and controlling (79.3%) were the most common compulsions, and contamination (89.7%) and magical thinking/superstition (44.8%) were the most common obsessions. The least frequent compulsions were hoarding/picking compulsions (17.2%), and the least frequent obsessions were sexual (3.4%) and religious (20.7%) obsessions. Based on the Children’s Yale–Brown Obsessive Compulsive Scale (C-YBOCS) total scores, 6 patients (20.7%) were evaluated as moderate, 17 (58.6%) as severe, and 6 (20.7%) as extreme cases.
3.3. Cytokines Levels: No significant difference was found between the groups in the levels of TNF-α (p = 0.983) , IL-1β(p = 0.357) , IL-2 (p = 0.135) , IL-6 (p = 0.458) , IL-10 (p = 0.877) , and IL-17 (p = 0.391) . A significant difference was found between the patient and control groups for TGF-1β(p = 0.002) levels. The data are shown in Table 2. High standard deviation was found for IL-6 in OCD group and the median (minimum-maximum) value was 15.5 (6.27-298.39). In addition, high standard deviations were found for TGF-1β, TNF-α and IL-6 in healthy control group and the median 1-2 (minimum-maximum) values were 136-147 (57-825), 6.18-6.43 (2.64-18.39), 20.98-21.77 (6.01-315.5) respectively. In OCD group, the median (minimum-maximum) values of TGF-1β and TNF-α were 147 (68-441), 5.83 (2.43-13.93) respectively. The Spearman correlation test revealed a weak negative correlation between TGF-1β levels and C-YOCBS total scores in the patient group (r =0.124 ; p = 0.032) . The data are shown in Table 3.
3.4. Neopterin , BH4, and NO Levels: Neopterin(p = 0.021) , BH4 (p = 0.001) , and NO(p = 0.013) levels were significantly different between the groups. The data are shown in Table 2. High standard deviation was found for neopterin in healthy control group and the median 1-2 (minimum-maximum) values were 7.59-7.59 (3.47-18.45). In OCD group, the median (minimum-maximum) value of neopterin was 8.16 (3.71-34.47). In the patient group, Spearman correlation test results showed a weak negative relationship between BH4 levels and C-YBOCS total scores(r =0.218 ; p = 0.001) , a statistically significant positive correlation between neopterin levels and C-YBOCS total scores (r = 0.352 ; p = 0.002) , and a weak positive correlation between NO levels and C-YBOCS total scores (r = 0.198 ; p = 0.005) . The data are shown in Table 3.
3.5. Correlation of Illness Duration with C-YBOCS Scores and Biological Data: Spearman correlation analysis revealed statistically significant positive correlations between the illness duration and the C-YOCBS obsession score (r = 0.431 ; p = 0.02) and total score (r = 0.401 ; p = 0.031) . There was no statistically significant correlation between illness duration and serum cytokine, neopterin, BH4, and NO levels. The data are shown in Table 4.