Suicidal Thoughts in Young French Adults: Depression Was the Biggest Factor, Cannabis Was Not Independent | Research

The takeaway

Among 4,075 young French adults, depression was the strongest predictor of suicidal ideation (OR ~8), while cannabis use in the previous month was not an independent predictor after adjusting for other factors.

Read this if you want to understand whether cannabis itself increases suicide risk or whether other factors explain the association.

Depression (OR ~8) was the strongest suicide risk factor; cannabis was not independently significant

What the researchers found

Researchers surveyed 4,075 French adults aged 18-30 about suicidal ideation, substance use, and psychosocial factors.

Suicidal ideation in the previous year affected 5.7% of men and 4.9% of women.

Depression was the strongest predictor for both sexes (adjusted OR approximately 8). Among men, other significant predictors included homosexual intercourse (OR 3.37), absence of sexual activity (OR 2.83), living alone, daily tobacco smoking, unemployment, and parental relationship quality.

Among women, forced sexual intercourse (OR 5.37) and illicit drug use other than cannabis (OR 4.01) were significant predictors.

Notably, cannabis use in the previous month was not independently associated with suicidal ideation in the adjusted models for either sex. Other illicit drugs (not cannabis) were significant for women only.

Why it matters

This large population-based study found that cannabis was not independently associated with suicidal ideation after accounting for depression and other psychosocial factors, consistent with the Swedish longitudinal study (RTHC-00381) finding that confounding explains the cannabis-suicide association.

The numbers in context

4,075 adults, ages 18-30. Suicidal ideation: 5.7% men, 4.9% women. Depression OR: ~8 (both sexes). Cannabis: not significant in adjusted models. Non-cannabis illicit drugs: OR 4.01 for women.

How the study worked

Cross-sectional analysis of 4,075 French adults aged 18-30 from a random national telephone survey in 2005. Depression assessed with CIDI-SF. Alcohol abuse assessed with AUDIT-C. Logistic regression with comprehensive adjustment for sociodemographic, health, and behavioral factors.

What this study cannot tell us

Cross-sectional design. Self-reported data via telephone survey. Cannabis use measured only in the previous month. French cultural context may limit generalizability. Telephone survey may miss marginalized populations.

How to read the evidence

Large population-based survey with comprehensive adjustment for confounders. Cross-sectional design limits causal inference.

When this study was published

Published in 2010. Subsequent research has continued to support the finding that confounding, particularly depression, explains much of the cannabis-suicidality association.

The bigger picture

Multiple studies now suggest that the association between cannabis and suicidality is largely explained by confounding factors, particularly depression and psychosocial adversity. Cannabis use may be a marker for these underlying risk factors rather than an independent cause.

Questions still open

Should suicide prevention efforts focus on depression treatment rather than substance-specific interventions? Are non-cannabis illicit drugs more relevant to suicidality risk in women? How do cultural factors affect the substance-suicidality relationship?

Common questions

Does cannabis increase suicide risk?

In this study, cannabis was not an independent predictor of suicidal ideation after accounting for depression and other factors. This is consistent with other large studies finding that the cannabis-suicide association is explained by underlying vulnerabilities rather than cannabis itself.

Why were other illicit drugs significant for women but not men?

The study found that non-cannabis illicit drug use was a significant predictor of suicidal ideation in women (OR 4.01) but not men. This may reflect gender-specific pathways between drug use and suicidality, possibly related to the different contexts in which men and women initiate illicit drug use.

Read the original research

Suicidal ideation among young French adults: association with occupation, family, sexual activity, personal background and drug use.

Journal of affective disorders, 123(1-3), 108-15

View on PubMed ↗Publisher’s paper ↗

Citation

Legleye, S; Beck, F; Peretti-Watel, P; Chau, N; Firdion, J M. (2010). Suicidal ideation among young French adults: association with occupation, family, sexual activity, personal background and drug use.. Journal of affective disorders, 123(1-3), 108-15. https://doi.org/10.1016/j.jad.2009.10.016