Objectives:
Limited data exist on the relationship between diabetes distress (DD), quality of life, and metabolic control in Polish adolescents with type 1 diabetes mellitus (T1DM) during transition to adult care. This study examines associations among Polish 18-year-olds with T1DM as they transition from pediatric to adult diabetes care.

Methods:
This cross-sectional study enrolled 110 consecutive patients aged 18 years with T1DM who completed the Problem Areas in Diabetes (PAID) questionnaire and Short Form Health Survey (SF-36v1). Continuous glucose monitoring (CGM) parameters were used to evaluate metabolic control.

Results:
Diabetes distress (DD) correlated with all quality of life scales but not with glycemic control. Women reported higher diabetes-related distress (p = 0.017) and poorer mental health (p = 0.009) than men. Smokers demonstrated worse glycemic parameters (p = 0.016) and poorer mental health (p = 0.008). Unexpectedly, poorer glycemic control was associated with better quality of life. A longer disease duration and an earlier age at onset were associated with worse glycemic control.

Conclusions:
Diabetes distress is more closely associated with quality of life than metabolic control in Polish 18-year-olds with T1DM. Females, individuals with longer disease duration, and smokers may benefit from targeted interventions emphasizing both psychological support and diabetes education.