Tobacco smoking is a leading preventable cause of morbidity and mortality globally [1,2]. The COVID-19 pandemic, caused by SARS-CoV-2, raised concerns about its interaction with tobacco use, as smoking impairs immunity and respiratory function [3-5]. India, with over 267 million tobacco users, faces particular challenges due to widespread use of cigarettes, bidis, and smokeless tobacco [6-8]. Chennai, a metropolitan hub, exemplifies this dual burden of high tobacco prevalence and COVID-19 incidence [9].   Evidence on smoking and COVID-19 outcomes remains mixed. Some studies report smokers as more likely to suffer severe complications [10,11], while others found unexpectedly low smoking prevalence among hospitalised patients [12,13]. Pandemic stressors and lockdowns altered tobacco availability and behaviours, leading some to quit while others increased use [14,15]. Behaviour changes theories, including the Health Belief Model, suggest perceived susceptibility and severity of disease motivate quitting [16].   Few Indian studies have assessed pandemic-driven changes in smoking. Understanding subgroup vulnerabilities by gender, residence, and smoking history is key for targeted interventions [17,18]. Moreover, linking behavioural changes to physical and psychological health can inform integrated strategies [19,20].

Design This was a descriptive cross-sectional survey of 500 adults aged 18–65 years in urban and rural Chennai.   Sampling Participants were recruited from a community health database. Inclusion criteria were self-reported tobacco use before the pandemic and willingness to provide consent. Non-users and incomplete responses were excluded.   Data Collection Structured questionnaires administered via telephone/online captured demographics, tobacco use patterns, COVID-19 history, hospitalisation/ICU admission, and self-rated health on a Likert scale. Smokeless tobacco was also recorded.   Analysis Data were analysed using SPSS v26. Paired t-tests assessed cigarette consumption changes; chi-square tests compared categorical outcomes. Logistic regression, adjusted for age, gender, residence, and smoking history, examined associations with hospitalisation, ICU admission, and health outcomes. p<0.05 was considered significant.

Demographics Of 500 participants, 310 (62%) were male, mean age 42±10 years. Urban residents comprised 55%. Long-term smokers (>10 years) represented 36%, see Table 1.   Table 1: Demographic Characteristics of Participants Characteristic n % Male 310 62 Female 190 38 Urban Residents 275 55   Behaviour Changes After the pandemic, 32% quit, 54% reduced, and 12% increased smoking. Cigarette use declined from 15.2±5.4 to 9.1±4.2 per day (p<0.001). Rural residents reduced more than urban counterparts (p<0.05), see Table 2.   Table 2: Changes in Smoking Behaviour and Health Outcomes Variable Pre-pandemic Post-pandemic p-value Cigarettes/day (mean ± SD) 15.2 ± 5.4 9.1 ± 4.2 <0.001 Quit Smoking 0 160 (32%) <0.001 Reduced Smoking 270 (54%) 50 (10%) <0.001   Health Outcomes About 18% reported COVID-19 infection, with 65% hospitalised and 25% admitted to ICU. Reduced/quit smoking was associated with lower hospitalisation (OR=0.42, 95% CI 0.25–0.72) and ICU admission (OR=0.35, 95% CI 0.19–0.65). Improved physical and psychological health was reported among quitters, Table 3 for reference.   Table 3: Multivariate Logistic Regression Analysis (Adjusted for Age, Gender, Smoking History) Outcome Predictor Adjusted OR (95% CI) p-value Hospitalisation Reduced/Quit Smoking 0.42 (0.25–0.72) <0.01 ICU Admission Reduced/Quit Smoking 0.35 (0.19–0.65) <0.01 Psychological Well-being Quitting Smoking 1.89 (1.11–3.24) <0.05

Our findings suggest the COVID-19 pandemic catalysed smoking reduction and cessation in Chennai, aligning with studies from China, the UK, and Spain [21,23]. However, male, urban, and long-term smokers were less likely to quit, consistent with literature linking gender norms, nicotine dependence, and access to resistance in behaviour change [24-26]. Participants who quit reported better psychological well-being, consistent with meta-analyses equating cessation with improved mental health [27,28]. These insights highlight opportunities for integrated interventions combining tobacco cessation with mental health support and digital counselling (29,30).

The COVID-19 pandemic acted as a behavioural turning point, prompting many smokers in Chennai to quit or reduce tobacco use. Disparities among men, urban residents, and long-term smokers emphasise the need for tailored cessation support. Integrating cessation with digital and mental health services may help sustain behavioural changes and strengthen public health resilience.   Limitations The study relied on self-report, raising recall and desirability bias. No non-smoker control group was included, limiting causal inference. COVID-19 infection and severity were self-reported and unverified. Despite these limitations, findings align with international studies and offer policy insights for targeted interventions [31-33].   Future studies should adopt prospective designs, bio-verify smoking status, and integrate qualitative research to explore motivations [34-36]. Policy should leverage crises as opportunities for cessation, embed tobacco control within pandemic preparedness, and use digital health tools for outreach [37-44].   Ethical Statement Institutional Review Board approval was obtained (SIMATS Ref: PHD/2025/04).