Objectives: Antioxidants, NSAIDs and Statins have been investigated for their preventive role in Alzheimer's disease but the results are inconclusive. Also, most of the studies are placebo controlled and have not compared these modalities against each other. Therefore, a network meta-analysis (NMA) was conducted to decide a potential candidate for future research. Methods: Efficacy was compared using the MMSE score. NMA was conducted using a Bayesian framework with non-informative priors in WinBUGS. This method combined direct and indirect evidence for any given pair of treatments and 95% credibility-intervals (CI) were constructed to assess the significance. The probability of each modality as the most efficacious regimen, the second best, the third best, and so on, was calculated using difference against placebo, and counting the proportion of iterations of the Markov chain in which each drug had the highest difference, the second highest, and so on. Results: The electronic database searches yielded 14 relevant studies. Overall 1,952 individuals were randomized to antioxidants (cyanocobalamin, folic-acid, tocopherol), NSAIDs (indomethacin, piroxicam, ibuprofen, diclofenac+misoprostol), statins (atorvastatin, pravastatin, simvastatin), or placebo. Results showed that atorvastatin was the most efficacious regimen with a MMSE score difference (95% CI) of -1.62 (-7.0, 3.8) against placebo; -2.27 (-8.9, 4.3) against cyanocobalamin; -1.67 (-9.2, 5.9) against folic-acid; -2.05 (-8.2, 4.1) against tocopherol; -8.27 (-16.4, -0.6) against indomethacin; -10.18 (-24.0, 3.7) against piroxicam; -1.71 (-9.2, 5.8) against ibuprofen; -3.23 (-13.7, 7.1) against diclofenac+misoprostol; and 0.09 (-6.6, 6.5) against simvastatin. The cumulative probabilities for being the best treatment were: atorvastatin (34%), simvastatin (25%), diclofenac+misoprostol (15%), folic-acid (9%), ibuprofen (8%), piroxicam (4%), cyanocobalamin (3%), tocopherol (2%), indomethacin (0%), and placebo (0%). Conclusions: We conclude that statins have a superior effect in comparison to NSAIDs and antioxidants. Therefore, statins may be preferred over other two therapies for further clinical investigation.
Pandey, R., Jha, D., Pandey, P., & Shah, V. (2016). Network Meta-Analysis of Randomized Trials to Compare the Efficacy of Nsaids, Statins and Vitamins in Alzheimer’s Disease. Value in Health, 19(7), A810. https://doi.org/10.1016/j.jval.2016.08.708