I am not an expert at this, though I have taken few credits of Biostatistics. I would be more interested if swapping the variables also gave significance in tes

I am not an expert at this, though I have taken few credits of Biostatistics. I would be more interested if swapping the variables also gave significance in tests. Did the Alzheimer's cohort also have a higher incidence of flu related comorbidities? I understand this is difficult - but this is why ANOVA tests also are extensively used to show variable dependence or report the degree of dependence. It is unclear from their findings. Without that we are probably looking at some positive correlation without investigating the causation.