The massive Taiwanese National Health Database strikes again! This time it was used to find new cases of depression between 1997 and 2010. The team found just over 55k cases. Of these, 13 823 received acupuncture treatment, and they were matched with an equal number who did not using a propensity score method (ie matching risk factors for the outcome).
Depression is associated with a substantial increase in the risk of a number of cardiovascular and cerebrovascular diseases.[2] For example, it is estimated that depression results in a 34% increase in the risk of ischaemic stroke and a 38% increase in the risk of haemorrhagic stroke.
I could see no mention of immortal time bias, so I hope this was taken into account!
The results indicate that acupuncture use was associated with a halving in the rate of stroke (adjusted hazard ration of 0.49). So it seems that acupuncture may have resulted in not only compensating for the deleterious effects of depression, but an overall risk reduction to below that of the non-depressed population in Taiwan. This must be seen as a very tentative suggestion since it comes from simply multiplying 1.38 (38% increase) by 0.49 and getting a figure under 1 (circa 0.7).
Another impressive result from the Taiwanese National Health Insurance Research Database, but I’m sure there is much more to learn.
References
1 Chen L-Y, Yen H-R, Sun M-F, et al. Acupuncture treatment is associated with a decreased risk of developing stroke in patients with depression: A propensity-score matched cohort study. J Affect Disord 2019;250:298–306. doi:10.1016/j.jad.2019.03.020
2 Daskalopoulou M, George J, Walters K, et al. Depression as a Risk Factor for the Initial Presentation of Twelve Cardiac, Cerebrovascular, and Peripheral Arterial Diseases: Data Linkage Study of 1.9 Million Women and Men. PLoS One 2016;11:e0153838. doi:10.1371/journal.pone.0153838