Efficacy of brief motivational interviewing on smoking cessation at tuberculosis clinics in Tshwane, South Africa: a randomized controlled trial

Authors

  • Goedele M. C. Louwagie,

    Corresponding author
    1. School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, South Africa
    • Correspondence to: Goedele M. C. Louwagie, Faculty of Health Sciences, School of Health Systems and Public Health, Private Bag X 323, Pretoria, 0001 SA, South Africa. E-mail: Goedele.louwagie@up.ac.za

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  • Kolawole S. Okuyemi,

    1. Department of Family Medicine and Community Health, University of Minnesota, Minneapolis, MN, USA
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  • Olalekan A. Ayo-Yusuf

    1. School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, South Africa
    2. Dean/Director's Office, School of Oral Health Sciences, Faculty of Health Sciences, University of Limpopo, Medunsa Campus, South Africa
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Abstract

Background and Aims

Tuberculosis (TB) patients who smoke risk adverse TB outcomes and other long-term health effects of smoking. This study aimed to determine the efficacy of brief motivational interviewing by lay health-care workers (LHCWs) in assisting TB patients to quit smoking.

Design

Multi-centre two-group parallel individual randomized controlled trial.

Setting

Six primary care tuberculosis clinics in a South African township.

Participants

Newly diagnosed adult TB patients identified as current smokers were randomized to brief motivational interviewing by a LHCW (intervention group, n = 205) or brief smoking cessation advice from a TB nurse (control group, n = 204).

Measurements

The primary outcome was self-reported sustained 6-month smoking abstinence. Exhaled carbon monoxide (CO) testing was offered to about half the participants. Secondary outcomes were sustained abstinence at 3 months; 7-day point prevalence abstinence at 1, 3 and 6 months; and quit attempts. Allocation was concealed. Primary analysis relied on intention to treat. Multi-level analysis accounted for site heterogeneity of effect.

Findings

Self-reported 6-month sustained abstinence was 21.5% for the intervention group versus 9.3% for the control group [relative risk (RR) = 2.29, 95% confidence interval (CI) = 1.34, 3.92]. Biochemically verified 6-month sustained abstinence was also higher in the intervention group (RR 2.21, 95% CI = 1.08, 4.51) for the 166 participants who were offered carbon monoxide testing. Self-reported 3-month sustained abstinence was 25.4% for the intervention group and 12.8% for the control group (RR = 1.98, 95% CI = 1.24, 3.18).

Conclusions

Motivational interviewing by lay counsellors to promote smoking cessation in tuberculosis patients in South Africa approximately doubled sustained smoking abstinence for at least 6 months compared with brief advice alone.

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