Health and economic burden of low back pain and rheumatoid arthritis attributable to smoking in 192 countries and territories in 2019

Background and aims: Smoking is a risk factor for low back pain (LBP) and rheumatoid arthritis (RA). We aimed to estimate the global health and economic burden of LBP and RA attributable to smoking. Design: This was a cross-sectional study. Setting: The study was conducted in 192 countries and territories. Cases: Prevalent cases of LBP and RA were used, extracted from the Global Burden of Diseases, Injuries and Risk Factors Study 2019 data repositories. Measurements: Smoking-attributable health and economic burden was estimated with the population-attributable fraction method. Smoking-attributable prevalence of LBP and RA and health-care costs were estimated for patients of all ages, whereas years lived with disability (YLDs) and productivity losses due to morbidity were estimated for patients aged 15–84 years. Uncertainty intervals (UIs) of the results were obtained by repeating the analysis with the lower and upper bounds of all input variables. Findings: Globally, smoking accounted for 84.5 million (UI = 56.7–120.2 million) prevalent cases of LBP, 1.8 million (UI = 0.5–3.4 million) prevalent cases of RA and 11.3 million (UI = 6.2–18.5 million) YLDs, which represented 1.5% of all-cause YLDs in the working-age population aged 15–84 years in 2019. Health-care costs and productivity losses of smoking-attributable LBP and RA cost the global economy purchasing-power parity $326.0 billion (UI = $184.0–521.4 billion), representing 0.2% of the global gross domestic product. Specifically, smoking accounted for $65.8 billion (UI = $38.0–101.2 billion) in health-care costs world-wide, with more than half [$39.8 billion (UI = $23.1–61.3 billion), 60.6%] borne by the public sector. Smoking also contributed to $260.3 billion (UI = $146.0–420.3 billion) in productivity losses globally. Approximately 60.0% of the global YLDs were observed in middle-income countries, whereas 84.4% of health-care costs and 72.7% of productivity losses were borne by high-income countries. Conclusions: Globally, in 2019, smoking accounted for more than 11.0 million years lived with disability and purchasing-power parity $326.0 billion in economic losses due to low back pain and rheumatoid arthritis. Middle-income countries suffered more morbidity, whereas high-income countries experienced larger economic losses.