Does smoking cannabis affect work commitment?

Aims: This study aimed to examine the associations between cannabis use and work commitment.

Design: We used a 25-year panel survey initiated in 1985 with follow-ups in 1987, 1989, 1993, 2003 and 2010. Registered data from a range of public registers were matched with individual responses for the entire period.

Setting: The panel survey was a nation-wide study set in Norway.

Participants: A total of 1997 respondents born between 1965 and 1968 were included in the panel.

Measurements: Work involvement scale (WIS) was used to assess work commitment. Involvement with cannabis was based on self-reported smoking of cannabis within the last 12 months and exposure to cannabis through friends. This information was categorized into 'abstaining', 'exposed', 'experimented' and 'involved'. Control measures included socio-economic background, mental health (HSCL-10), education, work satisfaction, unemployment, receipt of social assistance, consumption of alcohol, alcohol-related problems and use of other illicit drugs.

Findings: The level of work commitment was associated with involvement with cannabis. In 1993, when the respondents were in their mid-20s, those who were involved or had experimented with cannabis displayed lower levels of work commitment than those who were abstaining or merely exposed to cannabis through friends (P < 0.05). Work commitment among those who experimented with cannabis converged towards the levels reported by abstainers and the exposed as they grew older, whereas those involved reported decreasing work commitment into adulthood (P < 0.001). Using linear regression models for panel data, an association with continued use of cannabis across the life-course and a lowering of work commitment was established. Results remained significant even when controlling for a range of other factors known to be related to work commitment, such as socio-economic background, education, labour market experiences, mental health and family characteristics (P < 0.05).

Conclusions: In Norway the use of cannabis is associated with a reduction in work commitment among adults.