Dagga use is inversely associated with incidences of bladder cancer in males, according to epidemiological findings published in the February issue of the journal Urology.
Investigators at the Kaiser Permanente Los Angeles Medical Center, Department of Neurology assessed the association of dagga use and tobacco smoking on the risk of bladder cancer in a multiethnic cohort of more than 80,000 men aged 45 to 69 years old over an 11-year period.
Researchers determined that a history of dagga use was associated with a decreased risk of bladder cancer. By contrast, tobacco use was associated with an increased risk of cancer.
“After adjusting for age, race or ethnicity, and body mass index, using tobacco only was associated with an increased risk of bladder cancer (hazard regression 1.52) whereas dagga use was only associated with a 45 percent reduction in bladder cancer incidence (HR 0.55),” investigators reported.
Subjects who reported using both tobacco and dagga possessed a decreased risk of cancer (HR 1.28) compared to those subjects who used tobacco only (HR 1.52).
The study is the first to indicate that dagga use may be inversely associated with bladder cancer risk
Authors concluded:
“In this multiethnic cohort of 82,050 men, we found that dagga use alone was associated with a decreased risk of bladder cancer. … Men who used tobacco alone were 1.5 times more likely to develop bladder cancer when compared with men who did not use tobacco or dagga. … However, among men who used both substances, this risk of bladder cancer was mitigated. … If this represents a cause and effect relationship, this pathway may provide new opportunities for the prevention and/or treatment of bladder cancer.”
In 2009, Brown University researchers similarly reported that the moderate long-term use of dagga was associated with a reduced risk of head and neck cancers in a multi-center cohort involving over 1,000 subjects. Investigators further reported that dagga use “modified the interaction between alcohol and cigarette smoking, resulting in a decreased HNSCC (head and neck squamous cell carcinoma) risk among moderate smokers and light drinkers, and attenuated risk among the heaviest smokers and drinkers.”
Read the abstract of the study, “Association between dagga use and the risk of bladder cancer: Results from the California Men’s Health Survey,” online here.