The health impact of smokeless tobacco products: a systematic review

C Hajat; E Stein; L Ramstrom; S Shantikumar; R Polosa

doi:10.1186/s12954-021-00557-6

The health impact of smokeless tobacco products: a systematic review

Harm Reduct J. 2021 Dec 4;18(1):123. doi: 10.1186/s12954-021-00557-6.

Authors

C Hajat¹, E Stein², L Ramstrom³, S Shantikumar⁴, R Polosa^{5

6}

Affiliations

¹ Public Health Institute, UAE University, Abu Dhabi, 15551, UAE. Chajat@doctors.org.uk.
² Independent Researcher, New York, USA.
³ Independent Researcher, Institute for Tobacco Studies, Stockholm, Sweden.
⁴ Warwick Medical School, University of Warwick, Coventry, UK.
⁵ Center of Excellence for the Acceleration of HArm Reduction (CoEHAR), University of Catania, Catania, Italy.
⁶ Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy.

Abstract

Introduction: The objective was to systematically review studies on health outcomes from smokeless tobacco (SLT) products.

Methods: We analysed published literature on the health outcomes from SLT use between 01/01/2015 to 01/02/2020, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol using PubMed, Embase, Scopus, and Google Scholar.

Results: Of 53 studies included, six were global, 32 from Asia, Middle East and Africa (AMEA), nine from USA and six from Europe. 'Poor'-rated studies predominated (23;43%), in particular, for global (4;66%) and AMEA (16;50%). Health outcomes differed between SLT-products and regions; those in AMEA were associated with higher mortality (overall, cancer, Coronary heart disease (CHD), respiratory but not cardiovascular disease (CVD)), and morbidity (CVD, oral and head and neck cancers), with odds ratios up to 38.7. European studies showed no excess mortality (overall, CVD, from cancers) or morbidity (ischemic heart disease (IHD), stroke, oral, head and neck, pancreatic or colon cancers) from several meta-analyses; single studies reported elevated risk of rectal cancer and respiratory disorders. Pooled study data showed protection against developing Parkinson's disease. US studies showed mixed results for mortality (raised overall, CHD, cancer and smoking-related cancer mortality; no excess risk of respiratory or CVD mortality). Morbidity outcomes were also mixed, with some evidence of increased IHD, stroke and cancer risk (oral, head and neck). No studies reported on switching from cigarettes to SLT-products.

Conclusion: Our review demonstrates stark differences between different SLT-products in different regions, ranging from zero harm from European snus to greatly increased health risks in AMEA. The literature on the safety profile for SLT-products for harm reduction is incomplete and potentially misinforming policy and regulation.

Keywords: Cancer; Cardiovascular disease; Mental health; Moist snuff; Mortality; Respiratory disease; Smokeless tobacco; Smoking; Snuff; Snus; Tobacco; Tobacco harm reduction.

Publication types

Research Support, Non-U.S. Gov't
Review
Systematic Review

MeSH terms

Head and Neck Neoplasms*
Humans
Smoking
Tobacco Products*
Tobacco Use
Tobacco, Smokeless*