It is well recognised that individuals with both diabetes and mental health disorders have an increased risk of:

• poorer medication adherence⁵²
• decreased compliance with diabetes self-care; and
• are at higher risk of complications associated with diabetes⁵³

People with diabetes are more likely to experience mental health difficulties than people without diabetes, and those with pre-existing mental health problems can find managing diabetes an additional emotional burden. Anxiety and depression can make diabetes self-management more challenging partly because they reduce energy levels and motivation; thereby increasing the gap between actual and best possible self-management behaviours and resulting in poorer diabetes control.⁵⁴

Furthermore, many people with serious mental illness⁵⁵ live in areas that are socioeconomically deprived and are more likely to smoke, misuse alcohol or drugs, and take less physical activity. The culmination of factors results in a significantly increased risk of premature mortality for this population, largely due to cardiovascular disease.⁵⁶

Further associations between T2DM and mental health conditions are shown below.

Identifying common mental health problems in people with diabetes presents a significant challenge. This is partly because the symptoms of anxiety and depression are often similar to those of chronic diseases, and only a minority of people with anxiety and depression seek treatment.

The prevalence of depression in T2DM is approximately twice that found in the general population.⁵⁷ Depression can be in response to a diagnosis of diabetes, due to:

• considerable lifestyle and treatment demands on patients; and
• potentially debilitating complications and a reduced life expectancy.

The prevalence data:

• Clinically relevant depressive symptoms⁵⁸ among T2DM is approximately 30%, with the prevalence of major depressive disorder (MDD) around 10%, double that of those without a chronic medical illness.
• Individuals with depression have an approximately 60% increased risk of developing T2DM.
• The prognosis for comorbid depression and diabetes is worse than when each illness occurs separately.
• Episodes of MDD in individuals with diabetes are also likely to last longer and have a higher chance of recurrence compared with individuals without diabetes.⁵⁸

There is a higher prevalence of T2DM in people with severe mental illness. There is further increased risk of developing diabetes following the initiation of antipsychotic drugs.⁵⁹

This is particularly significant in those treated with atypical antipsychotics such as olanzapine, risperidone and quetiapine.

Over one in ten people taking these medications develop T2DM, in addition to being at higher risk of other metabolic disorders such as weight gain, dyslipidaemia and hypertension.⁶⁰

The Quality Prescribing Guidance on the use of antidepressants provides guidance on the management of depression and anxiety, but specific to those with T2DM.

• Individuals with T2DM should be regularly assessed for the presence of depressive and anxiety symptoms, in addition to other mental health disorders using validated tools. The PHQ9 questionnaire is commonly used in primary care, and has been validated for those with diabetes.⁶¹ GAD-7 assessment questionnaire can be used for assessment of anxiety.
• A holistic approach in the management of T2DM should be employed, as the entire spectrum of mental health disorders can influence diabetes-related outcomes. Poor emotional wellbeing is common in people with diabetes and a barrier to improved glycaemic control. This may be improved through combining effective approaches for alleviating depression, anxiety and distress with tailored interventions designed to improve self-management and glycaemic control.
  • Treatment modalities should be incorporated into primary care and self-management education interventions, to facilitate adaptation to diabetes and reduce diabetes-related distress.
  • To improve outcomes in this patient group, some of the methods that may be used are:
    • motivational interventions
    • stress management strategies
    • coping skills training
    • family therapy
    • collaborative case management
    • social prescribing options e.g. yoga, peer support, with information from community link workers
  • Individuals taking psychiatric medications, particularly atypical antipsychotics, should be encouraged to access regular screening of metabolic parameters such as blood pressure, weight, lipid profile and HbA1c to reduce future cardiovascular risk.
    
    

Services often struggle to deliver well-structured combined care with limited access to support from a psychiatrist or psychologist with experience in diabetes.  Through Mental Health in Scotland: Improving the Physical Health and Well Being of those Experiencing Mental Illness,⁶² the Scottish Government has committed to provide regular physical health checks for people with severe and enduring mental illness.