Beyond identity categories: chronotype and mental health as correlates of sleep quality in transgender and gender-diverse adults

Background – Sleep disturbance is frequently reported among transgender and gender-diverse (TGD) adults, yet the relative contribution of circadian preference, mental health, and gender-affirming hormone therapy (GAHT) remains unclear. Methods – In this cross-sectional study, 222 TGD adults (mean age = 26.9 ± 9.3 years; 15.3% non-binary) attending a specialized gender clinic in Padova (Italy) completed the Pittsburgh Sleep Quality Index (PSQI), Morningness–Eveningness Questionnaire (MEQ), and SF-12. Multivariable linear regression examined associations between sleep quality and chronotype, mental health-related quality of life, age, sex assigned at birth, gender identity, and current GAHT. An exploratory model tested the interaction between chronotype and GAHT status. Results – Mean PSQI was 6.31 ± 3.84; 54.9% scored >5 and 31.5% ≥8. Poorer sleep quality was independently associated with greater eveningness, lower mental health-related quality of life, younger age, and current GAHT. The association between eveningness and poorer sleep quality was stronger among participants receiving GAHT. Within the GAHT subgroup, treatment duration was not associated with PSQI scores. Conclusions – Poor sleep quality is common in TGD adults and appears primarily associated with circadian preference and psychological well-being. Findings suggest that the relationship between chronotype and sleep quality may vary by GAHT status, although no linear association with treatment duration was observed. Longitudinal studies are needed to clarify these relationships.