I see nothing wrong with simply reporting that in your particular sample or data set group B had a higher average age. This is the conditional, post-data perspective.
Read the section in BBR about the standard deviation not necessarily being a good summary stat.
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The mean and standard deviation are not descriptive of variables that have an asymmetric distribution such as variables with a heavy right tail (which includes many clinical lab measurements). Quantiles are always descriptive of continuous variables no matter what the distribution.
What conclusions to draw depends on other factors (ie. model assumptions and prior information). Is it possible that there is a relationship between variance and age that should be considered? Or is the higher variance merely a result of a much smaller sample in that group? Not much can be said about implications of the data without context.