Many people with chronic physical health conditions frequently experience mental illnesses such as anxiety and depression. Furthermore, mood disorders are common in individuals with neurodevelopmental disabilities such as autism. Recognition and diagnosis of mental illness and psychiatric disorders, particularly in individuals with neurodevelopmental disabilities is challenging. Additionally, physical illness may also present competing health and care demands as the management of physical conditions may often overshadow the recognition and treatment of psychiatric disorders. In individuals over age 60, the presence of two or more physical/mental conditions (multimorbidity) is becoming increasingly common. Multimorbidity is also occurring at younger ages especially in children with cancer and congenital conditions. Health and social care services in the UK provide limited integrated/joint support for physical and mental care needs. This leads to fragmented approaches which are inefficient and could result in the underdiagnosis of psychiatric conditions in people with existing physical or neurodegenerative conditions. Individuals with mental illness are at significant risk of self-harm, substance abuse and suicide. This risk might be exacerbated by the presence of physical conditions. This study aims to better understand the risk of mental illness in individuals with physical or neurodevelopmental conditions and the risk of self-harm, substance abuse and suicide following mental illness diagnosis.
This study aims to evaluate the cumulative burden and risk of psychiatric disorders, self-harm and substance abuse in patients with physical illness and neurodevelopmental disorders. The mean cumulative count method that captures recurring events will be used to estimate the cumulative burden. Specifically, we will investigate the cumulative burden of psychiatric events (anxiety, depression, schizophrenia, bipolar disorder and personality disorder) in individuals with physical conditions and neurodevelopmental disorders. Propensity score matching will be used to assemble the control cohorts. In patients with comorbid physical and mental illness, we will investigate the risk of non-fatal self-harm and substance abuse using a matched cohort study design. In patients who self-harm, we will investigate the risk of suicide following self-harm and other natural and unnatural causes of death. We will investigate the prescribing patterns of drugs that treat mental illness, adherence to these drugs and how these drugs affect subsequent self-harm and substance abuse. CPRD GOLD and Aurum primary care datasets and the Hospital Episode Statistics dataset will be used for case ascertainment of psychiatric disorders, physical conditions, self-harm and substance abuse. Adjusted Cox proportional hazards regression analysis will be used to estimate hazard ratios for risk of self-harm, substance abuse and mortality. Anxiety and depression are highly prevalent in England and Wales and the incidence of both conditions has been increasing over the past year due to COVID-19. This study will also enable the evaluation of mental illness drug adherence and efficacy to help shape treatment guidelines to reduce the incidence of self-harm and substance abuse.
Suicide (fatal and non-fatal); self-harm; substance abuse; psychiatric disorders (anxiety; depression; schizophrenia; bipolar disorder; personality disorder); mortality all-cause; mortality cause specific.
Outcomes related to adherence and persistence with mental health medications:
(i) Adherence (estimated as the proportion of days covered [PDC]) where patients having PDC > 80% were considered adherent.
(ii) Persistence (individuals prescribed with drugs as persistent until a prescription gap >90 days, in which case they were non-persistent, or there was no further longitudinal data (in which case persistence status was unknown beyond that time).
Alvina Lai - Chief Investigator - University College London ( UCL )
Alvina Lai - Corresponding Applicant - University College London ( UCL )
Wai Chang - Collaborator - University College London ( UCL )
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;Practice Level Index of Multiple Deprivation