Table 2. Power (two-sided α = 0.05) for two-sample mendelian randomization analysis.
| Exposure | Outcome-AD (Dataset) |
Participants in outcome | Proportion of cases in the outcome dataset | Causal Effect (exp(βxy)) |
R2 of instrument |
F statistics | Power (observed effect) |
|---|---|---|---|---|---|---|---|
| RHR | IGAP | 54,162 | 0.31 | 1.12 | 0.32% | 850.45 | 10.2% |
| RHR | MA-U | 314,278 | 0.10 | 0.84 | 0.34% | 895.12 | 40.1% |
| RHR | FA-U | 314,278 | 0.05 | 0.87 | 0.34% | 904.63 | 16.7% |
| RHR | FH-AD † | 388,324 | 0.19 | 0.97 | 0.33% | 870.45 | 6.3% |
| RHR | FH-AD § | 63,926 | 0.34 | 0.89 | 0.35% | 920.41 | 12.8% |
Notes:
Post-hoc power calculations were based on the method developed by Burgess (2014).8 Causal Effect = exponentiated estimate obtained from GSMR.
†
(FH-AD) GWAS conducted by Marioni et al. (2018).
§
(FH-AD 2) GWAS conducted by Kunkle et al. (2019).
AD, Alzheimer’s disease; RHR, resting heart rate; GWAS, genome-wide association study; IGAP, International Genomics of Alzheimer’s Project; FH-AD, a GWAS dataset from a combined meta-analysis; MA, maternal family history; FA, paternal family history.