We know that being physically ill can affect our mental health. Existing research shows us that multiple sclerosis and diabetes, for example, are both linked to mental health conditions including depression, anxiety and bipolar disorders. Arthritis is also linked to depression and anxiety.
However, some of this research is based on small sample sizes, and concentrates on these more serious psychiatric conditions. As part of my research, I’ve been using Understanding Society’s large, nationally representative data to understand how a number of common (or relatively common) illnesses are related to more general mental health and wellbeing.
Using the data
Many waves of Understanding Society have asked participants whether a doctor or other health professional has ever told them they have certain conditions. Multiple sclerosis (MS) appears in Waves 7-12, and diabetes and arthritis were asked about in Wave 1 and Waves 3-12.
In addition, each wave asks people about their mental wellbeing using the 12-item general health questionnaire (GHQ-12). This asks people about issues such as concentration, confidence, strain, and being able to enjoy normal day-to-day activities.
I wrote three papers – one each on MS, diabetes and arthritis – and in each case I looked at people’s GHQ scores as a whole, and divided the GHQ answers into three groups:
- six questions related to social dysfunction and anhedonia (reduced ability to experience pleasure)
- four related to depression and anxiety
- two related to loss of confidence.
This allowed me to look at links to mental health and wellbeing in general, and to see if the diseases in question were linked to specific aspects of mental health.
In each case, I compared people who had not been diagnosed with the disease with those who had:
- MS, using Wave 10: 78 people with MS, and over 38,000 without a diagnosis
- diabetes, Wave 1: 2,255 diabetes patients, and 14,585 participants who had not been diagnosed
- arthritis, Wave 1: 5,588 participants with an arthritis diagnosis, and 8794 participants without.
The social and economic questions in Understanding Society also allowed me to take into account factors such as age, sex, income, education, and marital status.
Findings – MS
I found that MS affects general mental health, which is consistent with previous research. This was expected, because there are potential physical causes – such as lesions in the brain caused by MS which could cause poor mental health – and psychological ones, such as the unpredictability of the disease, loss of control over one’s life, and financial complications.
It also affected social dysfunction and anhedonia, and loss of confidence. I didn’t find that MS was linked to depression and anxiety, but that may be down to the questions in that category. They ask about loss of sleep, having a problem overcoming difficulties, whether participants are unhappy or depressed, and general happiness. Other ways of assessing anxiety and depression ask many more questions, and it may be that this set is not the best way to measure depression and anxiety in people with MS.
Findings – diabetes
Again, I found that diabetes was connected to poorer mental health than in the control group. It was also linked to the three types of poor mental health: social dysfunction and anhedonia, depression and anxiety, and loss of confidence.
The link to poorer mental health in general is again consistent with existing research, but this study tells us more about how they are connected. It’s possible, for example, that anhedonia is linked to not being able to control one’s blood sugar level, and that other aspects of managing diabetes also affect mental health.
Findings – arthritis
Looking at arthritis, this too was linked to poorer mental health overall, and to social dysfunction and anhedonia, depression and anxiety, and loss of confidence. Once again, this echoes earlier research, suggesting that pain from arthritis lowers people’s quality of life, and fatigue causes mood changes.
The finding that arthritis patients have more loss of confidence problems was quite new, but previous studies have looked at the confidence of patients in coping with arthritis (and at spouses’ confidence in arthritis management).
Implications
Understanding how these illnesses (and others) can affect mental health is important when treating these patients.
In MS patients, for example, mental health is linked to the onset of MS and disease progression/relapses, so it’s important to monitor their mental health, perhaps using the GHQ-12. Neurologists should also work with mental health specialists to make sure that MS patients’ physical and psychological needs are met.
With diabetes, the mental health burden is well known enough to have a name: diabetes distress, describing the effect on people of having to monitor themselves continually, and the effect of the disease on their personal and professional lives. We also know that psychiatric issues, and psychosocial issues which are specific to diabetes, can reduce people’s self-management and thus their quality of life – and that psychiatric disorders in diabetes patients increase the risk of diabetes complications and early mortality.
Mental health problems can make treating arthritis problematic. We know that people with depression have high levels of perceptions of pain, and sometimes the non-inflammatory symptoms of arthritis can be bad enough to need an escalation in treatment, but this can result in the patient having an overdose of the drug in question. Again, regularly monitoring mental health in arthritis patients is important.
Limitations
In each case, I used one wave of the data – that is, I used it cross-sectionally, so I couldn’t test for causation. Also, the health measures are all self-reported, rather than objective, so it would be interesting to see if future research could take a longitudinal approach, and use objective measures – and look worldwide, rather than just at the UK. It also wasn’t clear whether participants with diabetes had type 1 or type 2, which could be another question for future research.
Read Weixi’s original research into the effect of multiple sclerosis on mental health, the association between diabetes and mental health, and mental health in arthritis patients
Weixi has also used Understanding Society to investigate life satisfaction and self-rated health in people with epilepsy
Authors
Weixi Kang
Weixi Kang is a PhD student in the Division of Brain Sciences, Department of Medicine, at Imperial College London
