I was coming here to say this is a survival analysis problem, and thus a different branch of probability and statistics. However, you can also frame it as a sto

I was coming here to say this is a survival analysis problem, and thus a different branch of probability and statistics. However, you can also frame it as a stochastic process if you have extra epigenetic data that is associated to those 50 DNA loci or some genes they regulate. For example, your DNA loci of interest could have a state (methylated or unmethylated). And you could come up with a stochastic process where death occurs when a function of methylation changes at those loci (e.g. a linear model) crosses a threshold (first passage in stochastic process jargon). Omer Karin & Uri Alon have published a similar concept to explain how the decreased capacity of immune cells to remove senescent cells leads to a Gompertz-like law of longevity, something that originates from actuarial studies! Their model is simpler as they deal with a univariate problem [1]. [1] https://www.nature.com/articles/s41467-019-13192-4 https://www.nature.com/articles/s41467-019-13192-4