Indian Researchers Develop Simple Calculator to Predict TB Death Risk at Diagnosis

A team of Indian researchers has developed a simple clinical calculator that can predict which tuberculosis (TB) patients face the highest risk of death at the time of diagnosis, according to a study published in the journal BMJ Open.

The tool, created by scientists from the ICMR-National Institute of Epidemiology (NIE) in Chennai and the Tamil Nadu TB programme, uses basic measurements routinely taken when a patient is diagnosed with TB. The researchers say it could be particularly useful in resource-limited settings that need scalable, data-driven ways to reduce TB deaths.

The study analysed data from 55,971 adult TB patients who were notified from public health facilities across Tamil Nadu between July 2022 and June 2023. It found that 7.4 per cent of patients died within a year of diagnosis, with nearly 68 per cent of those deaths occurring within the first two months.

The calculator relies on simple indicators such as body mass index (BMI), oxygen saturation, respiratory rate, pedal oedema (swelling in the feet) and the patient's ability to stand without support. When combined with age, sex, site of disease, previous treatment history and microbiological confirmation, the model accurately predicted the risk of death.

Researchers found that these simple triage indicators performed almost as well as more complex models based on multiple variables available later through the government's Ni-kshay TB database. They have recommended that severe-illness indicators be routinely captured at the time of TB diagnosis and have developed a TB death prediction calculator for use at diagnosis.

The study was led by researchers including Suseendar Shanmugasundaram, Dr Hemant Deepak Shewade and colleagues from ICMR-NIE, Chennai, along with officials from the Tamil Nadu TB programme. Senior author Dr Manoj V Murhekar, Director of ICMR-NIE, was among the researchers involved in the work.

India accounts for the world's largest TB burden, and reducing TB mortality remains a major public health challenge despite improvements in diagnosis and treatment. The researchers said the calculator could be used by Indian states and other high-burden countries seeking practical ways to identify vulnerable patients earlier.