Risk of premature death from tobacco smoking, alcohol, and social inequalities in urban India

Associations with mortality of social inequalities, smoking, and drinking differ widely between populations. During 1998-2001, 500,810 adults aged ≥35 were recruited from Chennai city in South India and followed to 2020 for verbal autopsy-assessed cause-specific mortality. Among those initially without chronic disease, multivariable-adjusted Cox regression (censored at age 70) related initial characteristics to mortality rates. Even among non-smoking non drinkers, those with no schooling had almost three times the mortality rate ratio (RR) of those with >11 years education (men: RR=2.76, 95% CI 2.58-2.95; women: RR=2.93, 2.69-3.19), with substantial mortality excesses from each major disease category. These social inequalities were further exacerbated by much higher smoking and drinking prevalences among less educated men. Adjusted for education, male smoking (vs not: RR=1.26, 1.22-1.29) and drinking (vs not: RR=1.52, 1.48-1.56) were independently associated with risk, and together almost doubled male mortality (both vs neither: RR=1.89, 1.84-1.94). Few women (<0.1%) smoked or drank.