Alcohol and cannabis abuse/dependence symptoms and life satisfaction in young adulthood.

INTRODUCTION AND AIMS

To examine the associations between substance abuse/dependence symptoms and life satisfaction, before and after adjustment for fixed and time-dynamic sources of confounding.

DESIGN AND METHODS

Data were drawn from a 30year longitudinal study of a birth cohort of 987 individuals. Associations between alcohol abuse/dependence symptoms, cannabis abuse/dependence symptoms and life satisfaction were examined using repeated measures regression models. Associations were adjusted for fixed and time-dynamic sources of confounding, including family background, personality, demographics, recent life events, current employment and recent mental illness.

RESULTS

There were significant associations between alcohol abuse/dependence and life satisfaction (P<0.0001) and between cannabis abuse/dependence and life satisfaction (P<0.0001). These significant associations remained after adjustment for fixed sources of confounding. However, adjusting for time-dynamic sources of confounding substantially reduced the associations. After adjustment for time-dynamic sources of confounding there were no significant associations between alcohol abuse/dependence and life satisfaction (P>0.17) or cannabis abuse/dependence and life satisfaction (P>0.25).

DISCUSSION AND CONCLUSIONS

These findings suggest that associations between life substance abuse/dependence and life satisfaction can be explained by time-dynamic factors, such as employment, life events and comorbid mental illness that are associated with reduced life satisfaction. When due allowance is made for confounding, alcohol and cannabis abuse/dependence are not associated with reduced life satisfaction.