Article Text

Download PDFPDF

Alcohol drinking and cigarette smoking in relation to risk of active tuberculosis: prospective cohort study
  1. Avril Zixin Soh1,
  2. Cynthia Bin Eng Chee2,
  3. Yee-Tang Wang2,
  4. Jian-Min Yuan3,4 and
  5. Woon-Puay Koh1,5
  1. 1 Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
  2. 2 Singapore Tuberculosis Control Unit, Tan Tock Seng Hospital, Singapore, Singapore
  3. 3 Division of Cancer Control and Population Sciences, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania, USA
  4. 4 Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania, USA
  5. 5 Office of Clinical Sciences, Duke-NUS Medical School, Singapore, Singapore
  1. Correspondence to Dr Woon-Puay Koh, Duke-NUS Medical School, Singapore, Singapore; woonpuay.koh{at} and Ms Avril Zixin Soh; avril.soh{at}


Introduction Heavy alcohol consumption increases the risk of active tuberculosis (TB). However, the relation between lower levels of alcohol intake and TB risk remains unclear. We aimed to evaluate the association between alcohol intake and risk of active TB and assess whether the associations were modified by smoking status, which is another risk factor for active TB.

Methods The Singapore Chinese Health Study is a prospective cohort of 63 257 adults aged 45–74 years recruited from 1993 to 1998. Information on alcohol intake and smoking history was collected at recruitment. Active TB cases were identified via linkage with National TB Notification Registry.

Results During a mean follow-up of 16.8 years, 1249 incident cases of active TB were identified. Among non-smokers, compared with total abstinence, participants who had monthly to weekly intake of alcohol had reduced TB risk (HR 0.70, 95% CI 0.55 to 0.89), but this reduction in risk with low-dose drinking was not observed among current smokers (HR 0.96, 95% CI 0.77 to 1.18; p for interaction=0.02). Comparatively, drinking 2+ drinks daily was associated with increased TB risk among current smokers (HR 1.51, 95% CI 1.11 to 2.05). This increased risk was not observed among non-smokers (HR 0.93, 95% CI 0.49 to 1.77) and the interaction between alcohol intake and smoking status was of borderline significance (p for interaction=0.08). In joint effect, compared with those who neither smoked nor drank, the risk of active TB increased from 1.82 (95% CI 1.57 to 2.10) in current smokers who were non-drinkers to 3.16 (95% CI 2.35 to 4.24) in current smokers who also drank 2+ drinks daily.

Conclusion While low intake of alcohol may protect against active TB among non-smokers, drinking 2+ drinks daily could act synergistically with smoking to increase the risk of active TB in current smokers.

  • tuberculosis

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:

View Full Text

Statistics from


  • Contributors AZS and W-PK contributed to the conception and design of the study and analysis of data. CBEC, Y-TW, J-MY and W-PK participated in the acquisition of data. AZS, CBEC, Y-TW, J-MY and W-PK were involved in the interpretation of the data and drafting of intellectual content. All authors read and approved the final manuscript and W-PK was responsible for the integrity of the work as a whole. W-PK is the guarantor.

  • Funding This work was supported by the United States National Cancer Institute, National Institutes of Health (grant numbers UM1 CA182876 and R01 CA144034). W-PK is supported by the National Medical Research Council, Singapore (NMRC/CSA/0055/2013). The sponsors have no role in: the study design; the collection, analysis or interpretation of data; the writing of the report or in the decision to submit the article for publication.

  • Competing interests All authors have completed the ICMJE uniform disclosure form at and declare: support from the National Institutes of Health for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.

  • Ethics approval The Institutional Review Boards of the National University of Singapore and University of Pittsburgh approved the conduct of the SCHS. The present study was approved by the Institutional Review Board of the National University of Singapore. All participants gave informed consent.

  • Provenance and peer review Not commissioned; internally peer reviewed.

  • Data sharing statement No additional data available.

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.