17% of Danish Cancer Patients Reported Peripheral Neuropathy, Higher in Cannabis Users | Research

The takeaway

Among nearly 2,840 Danish cancer outpatients, 17% had significant peripheral neuropathy symptoms, and cannabis users were nearly twice as likely to report a high symptom burden.

Oncologists managing treatment side effects; researchers studying neuropathy prevalence; patients interested in the relationship between cannabis and nerve symptoms.

29% of cannabis users vs 15% of non-users had high neuropathy scores

What the researchers found

Overall neuropathy prevalence was 17%, ranging from 6% to 33% across cancer types. Cannabis users had significantly higher neuropathy symptom scores (29% vs 15%, p<0.05). Patients with high neuropathy scores had substantially worse quality of life across all measures.

Why it matters

This is one of the largest surveys of neuropathy in a general oncology population. The finding that cannabis users had higher neuropathy scores is noteworthy, though it could reflect cannabis use for symptom management rather than cannabis causing neuropathy.

The numbers in context

2,839 patients surveyed (83% response rate). Overall neuropathy prevalence: 17%. Cannabis users with high score: 29% vs 15% non-users. Quality of life difference: -18.66 points on C30 SumScore (95% CI -20.31 to -17.02). Higher rates in females (19% vs 14%), smokers (21% vs 15%), patients living alone (21% vs 15%).

How the study worked

Cross-sectional survey administered to all adult outpatients at three Danish oncology departments. Used the EORTC-CIPN20 for neuropathy assessment and EORTC-QLQ-C30 for quality of life. A high symptom score was defined as CIPN20 summary score of 30 or above. Response rate: 83% (2,839 patients).

What this study cannot tell us

Cross-sectional design cannot determine whether cannabis use preceded or followed neuropathy symptoms. The study did not capture cannabis dose, frequency, or reason for use. Self-reported symptoms may differ from clinical assessment.

How to read the evidence

Moderate: large cross-sectional survey with 83% response rate across three centers, though causal direction cannot be determined.

When this study was published

Published in 2022.

The bigger picture

The association between cannabis use and higher neuropathy scores raises an important chicken-or-egg question. Patients with worse symptoms may turn to cannabis for relief, rather than cannabis worsening their condition. This distinction matters for clinical guidance.

Questions still open

Are cancer patients using cannabis because of neuropathy symptoms, or does cannabis worsen neuropathy? Would prospective tracking of cannabis use alongside neuropathy development clarify the direction of this association?

Common questions

Does cannabis cause neuropathy in cancer patients?

This study found an association but cannot determine causation. Patients with worse neuropathy may be more likely to try cannabis for symptom relief, creating a reverse-causation scenario.

How common is neuropathy across different cancer types?

Prevalence ranged from 6% to 33% depending on cancer diagnosis, reflecting differences in treatment regimens. The 17% overall figure provides a useful benchmark for general oncology populations.

Read the original research

The prevalence, distribution and impact of peripheral neuropathy among Danish patients with cancer - a population-based cross-sectional study.

Acta oncologica (Stockholm, Sweden), 61(3), 363-370

View on PubMed ↗Publisher’s paper ↗

Citation

Nielsen, Sebastian Werngreen; Eckhoff, Lise; Ruhlmann, Christina Halgaard Bruvik; Herrstedt, Jørn; Dalton, Susanne Oksbjerg. (2022). The prevalence, distribution and impact of peripheral neuropathy among Danish patients with cancer - a population-based cross-sectional study.. Acta oncologica (Stockholm, Sweden), 61(3), 363-370. https://doi.org/10.1080/0284186X.2021.2007283