Almost a quarter of tuberculosis (TB) patients are “severely psychologically distressed” and are consequently less likely to complete the six-month course of treatment and be cured.
This “nonadherence” can lead to them becoming resistant to the antibiotics and developing more dangerous and resistant forms of the disease.
This is according to a study by University of Cape Town (UCT) researchers that was published this month in the journal BMC Infectious Diseases, and is the first time a link has been proved to exist between mental health and adherence to treatment in TB patients.
Defaulters put community at risk
More than 1 500 people took part in the study, which was conducted in five sites across Southern Africa: Durban and Cape Town in South Africa, Lusaka in Zambia, Harare in Zimbabwe and Mbeye in Tanzania.
The extent of their psychological distress was evaluated through a questionnaire and is defined as a state of “emotional suffering” characterised by symptoms of depression and anxiety.
According to a 2014 South African Medical Journal study, 79% of South African TB patients complete their treatment or are cured, which is short of the national health department’s target of 85%.
Patients who do not complete the course of anti-TB drugs are more likely to transmit the airborne disease to others in their community. They are also more likely to develop multidrug-resistant TB and extensively drug-resistant TB – both of which require two years of treatment with toxic drugs that have severe side effects that can include deafness.
High cost of drug-resistant TB
Gilles van Cutsem, of Médecins Sans Frontières South Africa, said that while “normal” TB is estimated to cost as little as $19 per patient to treat, drug-resistant TB costs at least $4 000 and requires a patient to take more than 14 000 pills over two years.
In a 2010 study published in Social Behaviour and Personality, 64% of TB patients surveyed in Cape Town were depressed, correlating with the UCT study’s finding that “severe psychological distress [is] frequent among patients seeking care for TB in Southern Africa”.
The UCT researchers note that screening and counselling for psychiatric illness “is poorly integrated with TB care and is infrequently available to patients attending clinics in high-burden, resource-limited settings”.
They conclude that screening for psychological distress could, “together with counselling to reduce alcohol consumption and improve patients’ knowledge about TB, reduce treatment nonadherence”.