Background: The magnitude and timing of the impact of effects of smoking cessation on inpatient and outpatient health care use are uncertain.
Methods: Comparison of the use of outpatient and hospital services over time of 2440 persistent smokers and 244 biochemically verified quitters, all of whom were participants in two independent randomized trials of smoking cessation interventions.
Results: Continued smokers in both trials experienced a 7% to 15% increase in outpatient visits and a 30% to 45% increase in hospital admissions over 5 to 6 years of follow-up. The positive slopes approached or reached statistical significance for all use variables in both trial populations. Among quitters, all health care use rates significantly increased during the year in which they quit; after that, the rates declined progressively. By the fourth year after quitting, all use rates among quitters were lower than those for smokers. The increase in hospitalizations during the year of quitting was more often a cause rather than a consequence of successful smoking cessation.
Conclusion: Successful smoking cessation appears to halt the progressive increase in the use of health services associated with continued smoking within a 4-year period.