Ethnicity, Migration, and Mental Health: Independent Risk Factors Persist in Type 2 Diabetes Disparities

Key Highlights

1. Ethnic minorities (South Asian, Black African, Black Caribbean) have 2-3 times higher type 2 diabetes risk than White British individuals.

2. Being born outside the UK increases diabetes risk by 29%, independent of ethnicity.

3. Depression, anxiety, and severe mental illness independently elevate diabetes risk, with no significant interaction effects across ethnic groups.

Background

Type 2 diabetes prevalence varies significantly by ethnicity, but the roles of migration and mental health in these disparities remain understudied. This study leverages a unique primary care dataset from South London to examine these intersecting factors longitudinally.

Study Design

This longitudinal cohort study (2012-2019) analyzed approximately 340,000 adults without baseline diabetes from multiethnic primary care populations. Cox models were adjusted sequentially for:
1. Age/sex
2. Migration status (UK-born vs. non-UK-born)
3. Mental health conditions, physical comorbidities (BMI, hypertension), and area deprivation.

Key Findings

Ethnic disparities persisted after full adjustment:

• South Asian: HR 2.72 (95%CI 2.56-2.89)
• Black African: HR 2.36 (2.20-2.53)
• Black Caribbean: HR 2.04 (1.91-2.17)

Migration and mental health showed additive effects:

• Non-UK birth: HR 1.29 (1.25-1.33)
• Depression/anxiety: HR 1.13 (1.09-1.17)
• Severe mental illness: HR 1.20 (1.10-1.30)

Expert Commentary

“These findings underscore that current screening and prevention strategies inadequately address the structural drivers of diabetes disparities,” notes Dr. Das-Munshi, senior author. The lack of interaction effects suggests generalized mechanisms (e.g., stress pathways) rather than ethnic-specific amplification. Study limitations include potential residual confounding by unmeasured lifestyle factors.

Conclusion

Persistent ethnic disparities require multifactorial interventions addressing post-migration challenges, mental health integration, and structural inequities. Future research should explore targeted prevention for high-risk groups while addressing systemic determinants.

References

Shamsutdinova D, et al. Diabetologia. 2026; PMID: 42018145.