A note on age-related comorbidity

A few years ago a link was found between age-related maculopathy and senile dementia. A pointer to this might have been provided prospectively by a comparison of the partial correlation of the respective age-related prevalences. Here the question is asked whether this was an isolated example or whether it can be confirmed in a statistically significant number of comparisons. Published data on age-related prevalences of 15 conditions have been partially correlated in order to determine whether their correlations, if any, persist when the variable of age has been eliminated. This was the case in a significant fraction of the data, and, for a smaller, but still significant, fraction it was possible to find retrospective confirmatory evidence. The approach is held to provide a short-cut method for exploring possible, hitherto unestablished, links between existing studies, which, in turn, may lead to a better understanding of the nosology underlying them.