Mortality and cancer incidence among physicians of traditional Chinese medicine: a 20-year national follow-up study.
OBJECTIVE
To study the risks of mortality and cancer incidence in physicians of traditional Chinese medicine (TCM) who had frequent exposure to herbal medicine.


METHODS
A population-based cohort design was conducted in which a total of 7675 certified physicians of TCM who ever practised between 1985 and 2005 were compared with the age-, sex- and calendar year-specific mortalities and cancer incidence rates of the general population of Taiwan. The age-, sex- and calendar year-standardised mortality ratio (SMR) and standardised cancer incidence ratio (SIR) were calculated to estimate the relative risks of all causes and site-specific mortality and cancer incidence.


RESULTS
Over an up to 20-year observational period, 796 (10.4%) physicians of TCM died, and 279 (3.6%) developed cancer. The study cohort showed a significantly reduced SMR for all-causes mortality (68, 95% CI 63 to 73), and for deaths from infectious (SMR=64), circulatory (SMR=68), respiratory (SMR=64) and digestive (SMR=56) disease. The study cohort also had a significantly reduced SIR (80, 95% CI 71 to 90) for all cancers, and for neoplasm of rectum, rectosigmoid junction, and anus (SIR=45), female breast (SIR=30) and cervix uteri (SIR=10). On the other hand, we noted that physicians of TCM suffered from a significantly increased SIR for neoplasm of liver and intrahepatic bile ducts (SIR=151, 95% CI 116 to 192) and of bladder cancer (SIR=259, 95% CI 167 to 382).


CONCLUSIONS
Like other healthcare workers, we noted that physicians of TCM had significantly reduced risks of all-causes mortality and cancer incidence. Nonetheless, reasons truly responsible for significantly increased risks of liver and bladder neoplasm among physicians of TCM warrant further investigations.
Institute of Environmental Health, College of Public Health, China Medical University and Hospital, 91 Hseuh-Shih Road, Taichung 404, Taiwan.
Shu-Hui
SH
Liu
Yu-Feng
YF
Liu
Saou-Hsing
SH
Liou
Yun-Lian
YL
Lin
Yuen-Chen
YC
Hsiao
Chu-Chieh
CC
Chen
Chung-Yi
CY
Li
Trong-Neng
TN
Wu
D000328:Adult; D002423:Cause of Death; D015331:Cohort Studies; D004365:Drugs, Chinese Herbal / Q000009:adverse effects; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008113:Liver Neoplasms / Q000401:mortality; D008297:Male; D008516:Medicine, Chinese Traditional; D008875:Middle Aged; D009369:Neoplasms / Q000401:mortality*; D009784:Occupational Diseases / Q000401:mortality*; D016273:Occupational Exposure; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D001749:Urinary Bladder Neoplasms / Q000401:mortality; D055815:Young Adult
D004365:Drugs, Chinese Herbal