This ‘nationwide, population-based ‘cohort study’ was meant to investigate the probable effect of TCM to decrease the fracture rate. Its authors identified cases with osteoporosis and selected a comparison group that was frequency-matched according to sex, age (per 5 years), diagnosis year of osteoporosis, and index year. The difference between the two groups in the development of fracture was estimated using the Kaplan-Meier method and the log-rank test.
After inserting age, gender, urbanization level, and comorbidities into the Cox’s proportional hazard model, patients who used TCM had a lower hazard ratio (HR) of fracture compared to the non-TCM user group. The Kaplan-Meier curves showed that osteoporosis patients who used TCM had a lower incidence of fracture events than those who did not. Our study also demonstrated that the longer the TCM use, the lesser the fracture rate.
The authors concluded that their study showed that TCM might have a positive impact on the prevention of osteoporotic fracture.
The authors also mention three weaknesses of their study:
- Firstly, we were unable to include medicines taken at the patient’s own expense. According to the specification of the NHI program, Western medicine for osteoporosis can only be applied after a fracture occurred. It is possible that the patients source such medicines at their own expense when they were diagnosed with osteoporosis before a fracture happens.
- Secondly, some data related to fractures, such as a patient’s exercise, lifestyle, BMI, alcohol, and cigarette use is not available from the NHI program.
- Thirdly, the Kaplan–Meier curve might be influenced by economic levels and patient severity. However, we can conclude that TCM might have a positive impact on the prevention of osteoporotic fracture…
Disregarding these limitations, they nevertheless state that their study not only reveals the preventative value of TCM use for patients with osteoporosis in the clinical setting, but also provides valuable information regarding the most common prescriptions provided to osteoporotic patients.
So, is there a causal link between TCM and osteoporosis?
Yes, it is possible.
But is it proven?
Is it likely?
By far the most plausible explanation of the findings is that the two groups that were compared here were not comparable in many ways that affect the osteoporosis-risk.
Major risk factors of osteoporosis include:
- Inadequate nutritional absorption
- Lack of physical activity or fall risk
- Weight loss
- Cigarette smoking
- Alcohol consumption
- Air pollution
I suggest therefore that this study shows that the two populations differed regarding these risk factors.
I also suggest that researchers of SCAM might benefit from a minimum of critical thinking.
I furthermore suggest that, if SCAM-fans want to test whether causal effects exist, they use controlled clinical trials rather than cohort or case-control studies
Lastly, I suggest that authors, journal editors, reviewers and funders (this study was funded by the ‘Taiwan Ministry of Health and Welfare Clinical Trial Center’) remind themselves that they have a responsibility and thus avoid misleading the public.