Canberra, Philadelphia and Manchester — Depression is often distinguished from other non-communicable diseases or NCDs (e.g., cancer, diabetes, cardio-vascular diseases, hypertension) because of the stigma attached to it. Among other consequences, those suffering from depression are often denied access to medical care. Indeed, the latter is an outcome of interaction between supply of and demand for medical care. On the provider side, stigmatizing attitudes by service providers are identified as a barrier to access. On the demand side, stigma and low mental health literacy by community members are just as emphatically reported as barriers to accessing care.
But there are striking similarities between depression and other NCDs too. There are strong inter-relationships between them (eg, between depression and cancer, depression and diabetes, depression and strokes).
Many NCDs share common risk factors such as tobacco use, physical inactivity, and unhealthy diets that are associated with cardio-vascular diseases (CVDs), diabetes, and cancer. The South African adult population has high levels of these risk factors, and large proportions of the disease burden can be attributed to these modifiable risk factors. Mental disorders increase the risk of all these diseases, which in turn increase the risk of mental disorders (Patel et al.2018 a).
Our recent study focuses on the association from depression to other NCDs, based on a state-of-art analysis of the five waves of the National Income Dynamics Study (NIDS) panel survey data for South African adults (30 years and above) for 2008, 2010, 2012, 2014, and 2016/17 (Pandey et al. 2019). NCD outcomes are the dependent variable with depression in the initial year and other explanatory variables that vary with time or do not. Examples of the former include age, wealth, whether living alone and affiliation to social networks, and of the latter gender and ethnicity. Although much has been written on the association from NCDs to depression, the research on the reverse association from depression to NCDs remains patchy. Hence the focus here is on the latter.
There are robust associations from depression to other NCDs in South Africa. With controls for socio-economic factors, the initial condition of moderate and severe depression is robustly associated with NCDs such as high blood pressure, stroke, heart diseases, cancer, and at least one NCD in subsequent years. This result is also consistent for mental health conditions where poor baseline mental health condition increases the risk of NCDs later. Moreover, the risk of NCDs is higher when severe depression or poor mental health conditions are present (with or without NCDs)--with a slightly larger risk when severe mental health conditions co-occur with an NCD in the initial year.
Although there is no evidence of a gradient between NCDs and wealth quartiles, there are a few striking contrasts. Relative to the wealthiest (in the top 25% bracket or 4th quartile), the least wealthy (bottom 25%/first quartile) are less likely to suffer from diabetes, high blood pressure, and stroke, while those in the second quartile show a lower risk of stroke. So the proposition that NCDs are diseases of affluence cannot be rejected outright.
Relative to the Africans, the Whites are less likely to suffer from diabetes but more vulnerable to heart diseases, cancer and at least one NCD. The Coloureds have higher risks of NCDs while the Asians/ Indians are more vulnerable to diabetes and heart related problems. At older ages, the proportion of black Africans is higher than it was previously which accounts for the decrease in lung cancer because black Africans have a lower rate of smoking than White and Coloured people. The South African Indian community is more insulin resistant than other ethnic groups and therefore at greater risk of diabetes type 2 and ischaemic heart disease.
The Lancet Commission on global mental health and sustainable development (2018) and WHO (2015) report adverse impacts on the health of the caregivers. Caring for a person with a chronic, disabling NCD or mental disorder, such as cancer or dementia, is stressful and associated with an increased risk of chronic health problems, including depression, hypertension, sleeping problems, and fatigue; increased use of psychotropic drugs; and premature mortality. Indeed, such indirect impacts on caregivers, who are often members of the patient's household, result in sick households.
The Mental Health Care Act 17 of 2002 in South Africa requires that service users undergo a 72-h emergency management and observation period for involuntary admissions to designated general district and regional hospitals across the country, before they are referred to specialist psychiatric hospitals. However, implementation remains daunting, with inadequate infrastructure and specialist staff. Indeed, several studies are emphatic that this requirement has negatively affected the quality of care provided (Petersen et al. 2017).
A policy shift from a singular disease focus to individual patient as one unit is needed. In the South African context, for example, diabetes and depression are separated within the health-care institution so that someone with depressive symptoms during routine diabetes care does not simultaneously get medical attention for the former. Of particular importance is integration of depression and NCD care in primary health care with a view to increasing prevention, screening, self-management, treatment and rehabilitation in order to achieve equitable, efficient and quality health services in South Africa. Arguably, simultaneous medical care for mental disorder and other NCDs also has considerable potential for overcoming the stigma of a mental disorder. However, the integration has been impeded by lack of trained doctors and nurses, essential equipment, its poor maintenance, and adequate funding.
A case could be made for substantially higher investment in primary health-care systems (Patel et al. 2018 b). On the supply side, these investments include greater accountability of services to local communities, enhanced sensitivity of providers to local conditions and beliefs, and provision of care to the needy. On the demand side, effective local services can address complex problems of patient access, offset the financial burden of adult chronic illness, and restrict unnecessary use of expensive private care. Although additional resources are needed, the magnitude is likely to be less than projected if the efficiency of investment in primary medical care is factored in.