A brief motivational intervention targeting tobacco smoking, alcohol and medication adherence to improve TB treatment outcomes in adult TB patients: A multi-center, randomised controlled trial of the ProLife programme in South Africa

<b>Introduction</b><b><br></b>South Africa has one of the highest TB burdens in the world. Smoking, harmful alcohol use and poor medication adherence may adversely affect TB treatment outcomes. We aimed to investigate the effectiveness of a complex behavioural intervention, ProLife, on TB treatment success (primary outcome) and medication adherence, alcohol use and tobacco smoking. <b>Methods </b> The intervention, delivered by lay health workers, consisted of motivational interviewing (MI), augmented with subsequent SMS, targeting medication adherence, alcohol use and tobacco smoking as appropriate. This was a multi-centre, individual, randomised controlled trial where participants were randomly assigned (1:1) to the ProLife intervention or usual care. Participants were adults with drug-sensitive pulmonary TB from 27 clinics who smoked and/or reported harmful or hazardous alcohol use. Questionnaires were administered at baseline, 3 and 6-months. Clinical information and TB treatment outcomes were obtained from patients’ records. <b>Results</b> Between 15 November 2018 and 31 August 2019, 574 participants were randomised to receive either the ProLife intervention (n=283) or usual care (n=291). TB treatment success rates at 6-9 months did not differ significantly between intervention (67.8%) and control (70.1%) (OR=0.9 (95% CI: 0.64,1.27)). There was also no evidence of an effect on continuous smoking abstinence (OR=0.76 (95% CI: 0.35,1.63) at 6-months; OR=0.65 (95% CI: 0.37,1.14) at 3-months) or TB medication adherence (OR=0.89 (95%CI: 0.26,3.07) at 6-months; OR=1.22 (95%CI: 0.52,2.87) at 3-months). The mean Alcohol Use Disorder Identification Test score was lower in the intervention arm by 0.04 points (95% CI: -2,1.91) at 6-months; and higher by 0.55 (95% CI: -1.01,2.11) at 3-months adjusting for baseline values. Adherence to MI counselling principles was fair. The mean cost of the intervention was $180.02 ($0.42) per participant. <b>Conclusion</b> The ProLife intervention was not effective. Targeting multiple health risk behaviours with MI and SMS may not be an effective approach to improve TB outcomes.