Objective:

To investigate the associations between TSH levels, glycolipid metabolism parameters, and suicidal ideation in adolescents with MDD.

Approach:

• Study Design: Cross-sectional study conducted in Anhui Province, China.
• Participants: 146 adolescents with MDD and 70 healthy controls were enrolled.
• Assessment Tools: Depressive symptoms and SI severity were assessed using HAMD-24 and PANSI.
• Data Collection: Socio-demographic data, laboratory parameters, TSH levels, and glycolipid metabolism parameters were collected.

Key Findings:

• Adolescents with MDD had significantly lower fasting blood glucose levels compared to healthy controls (P < 0.001).
• Worse family relationships, higher HAMD-24 scores, and elevated TSH and FBG levels were independently associated with suicidal ideation (all P < 0.05).
• The combination of these factors demonstrated a good discriminatory ability for suicidal ideation, with an area under the curve (AUC) of 0.851.

Interpretation:

TSH and FBG levels are associated with SI in adolescents with MDD, but further validation in larger studies is needed to determine their clinical utility as biomarkers.

Limitations:

• Cross-sectional design limits causal inferences.
• Sample size may not be representative of the broader population.

Conclusion:

Further research is warranted to explore the associations between TSH and FBG levels and suicidal ideation in adolescents with MDD.