Adults with cerebral palsy at higher risk for depression, anxiety

Mathias Castaldo is a member of Holland Bloorview's youth advisory and participated in our Dear Everybody campaign to end disability stigma. “The minute we tell someone they cannot do something because they are disabled, we disempower them. We take away their desire to have dreams and to achieve those dreams, and we ultimately take away that person’s spirit.”

By Louise Kinross

Adults with cerebral palsy (CP) have higher rates of depression and anxiety compared to the general population, according to a British population-based study in a primary-care setting.

The study, published in JAMA Neurology on Dec. 28, compared diagnoses of depression and anxiety in 1,705 adults with CP with 5,115 adults without CP who were of the same age and sex and from the same primary-care practice. Adults with CP had a 28 per cent increased risk of being diagnosed with depression and a 40 per cent greater risk of being diagnosed with anxiety. Participants were aged 18 to 89 and received a diagnosis between 1987 and 2015.

BLOOM interviewed two of the authors by e-mail: Kimberley Smith, a lecturer in health psychology at the University of Surrey and Jennifer Ryan, a research lecturer at the Royal College of Surgeons in Ireland.

BLOOM: Why was there a need for this study?

Kimberley Smith: There isn't much research that's been done looking at mental health in adults with CP. Most of the research is in children. Being an adult with CP is different than being a child with cerebral palsy, so we can't apply results from children to adults.

Jennifer Ryan: Our anecdotal experience suggested mental health conditions are prevalent among adolescents and adults with CP. From speaking with young people and adults, we were also aware that often mental health problems are more challenging and have a greater impact on their wellbeing than their physical impairment.

BLOOM: Were you surprised by the findings?

Kimberley Smith: Not really, to be honest. People who live with any long-term conditions have around double the risk of depression and anxiety than people who don't have a long-term condition.

Jennifer Ryan: We also suspected this was the case from speaking to people with CP and the health professionals who work with them.

BLOOM: In a piece Kimberley wrote for The Conversation online, you discuss some of the reasons adults with cerebral palsy may be at higher risk. These include physical causes, such as pain and fatigue, as well as social isolation, stigma, unemployment and lack of accessibility. Why is there so little research on mental health in this population?

Kimberley Smith: Research into aging with CP is still developing, and we've lacked research on the development of both mental and physical illness. We think it's because historically CP was considered a childhood condition, and people didn't really consider that most people with CP have normal life expectancy. Due to this, researchers tended to focus on childhood only. The problem with this is that we lack the evidence required to support the need for specialized care for adults with CP.

Jennifer Ryan: Perhaps the reason there's a lack of research on adults is because services for people with CP are typically organized on a pediatric model. We've found that it's very difficult to conduct research involving adults with CP because there's rarely one service where we can access them.

BLOOM: Research here at Holland Bloorview almost 20 years ago showed the increased risk of secondary conditions that result from poor care when youth transition to the adult health system. It's referred to by families as 'falling off the cliff.' We're very aware, for example, of adults with CP who desperately need physiotherapy, but are unable to get funded therapy, so go without. And adults who are unable to find specialists who understand their condition. I'm assuming the situation is similar in the U.K.?

Kimberley Smith: It's a bit different as we have funded healthcare through the NHS, but we also have the same issues around transitions from youth to adult-care services. A researcher called Professor Allan Colver in the U.K. has done research into how we could improve this. However, we're still a long way from having specialized adult CP services.

In order to advocate for this, two women set up a charity called the Adult CP Hub in the U.K. We as a research team are also in the process of publishing a series of papers on the risk of different illnesses in adults with CP, which we hope will create some of the evidence required to support the need for these services.

Jennifer Ryan: We've also heard families in the U.K. and Ireland use the term 'falling off the cliff.' Even when pediatric services try to prepare them for the transfer to adult services, people are usually still shocked when they realize how few services there are and how difficult they are to access. In particular, it's difficult to access professionals working in adult services who have knowledge of CP.

In the U.K. and Ireland, the difference in pediatric and adult clinician roles is a real challenge for people with CP. While pediatricians typically coordinate the care of young people with CP, there's a severe lack of adult rehabilitation physicians. There are also differences in the eligibility criteria for children's and adult services, which results in adults often not being eligible for services they received in childhood.

BLOOM: Is anyone studying what interventions for depression and anxiety are most effective for adults with CP? When I posted a link to your article on our Facebook page, one reader said that antidepressants increased her spasticity. So I wondered if there were studies examining what treatments work best?

Kimberley Smith: The only researcher I'm aware of who might be looking into this is Dr. Daniel Linhares, based at Columbia University in New York. This is a link where he talks about the use of antidepressants in adults with CP.

BLOOM: I just found this story about a new centre for adults with CP at Columbia!

Your study found an increased risk in depression and anxiety for adults with CP and no intellectual disability. It didn't find the same increase in adults with intellectual disability. This seems odd, in that adults with intellectual disability would have the same physical problems, such as pain and fatigue, and face the same stigma. Is it possible that depression and anxiety in adults with CP and intellectual disability is missed by clinicians?

Kimberley Smith: Based on our work, we can't say for sure. One reason could be due to 'diagnostic overshadowing:' this is a term used to describe when distress presents as challenging behaviours, rather than as the symptoms we have been taught to link with depression and anxiety. This could mean that depression and anxiety are missed.

However, there is also work that's been conducted in populations of people with intellectual disability that indicates that the prevalence of anxiety and depression in these individuals is no different from the general population. In short, we don't really know, but it's really important that as researchers we try and find out.

BLOOM: You mentioned this study is part of a series on aging in CP. 

Kimberley Smith: We have one study written by Jennifer on the increased risk of death from non-communicable diseases in adults with CP. It was recently accepted for publication in Developmental Medicine and Child Neurology. There are also two other papers looking at the risk of developing non-communicable diseases and arthropathies in adults with cerebral palsy. Both have been submitted for publication and we're keeping our fingers crossed!