Late-onset delusional depression: a distinct clinical entity?

A comparison of the prevalence of delusions was made between early-onset (less than age 60) and late-onset (greater than or equal to age 60) primary endogenous depressives. Depressives with onset after age 60 had delusions more frequently than those with earlier onset. Fourteen of 16 late-onset depressives but only 5 of 18 earlier onset patients were delusional (p less than .005). Within the early onset group, those with delusions tended to be older at index episode than those without delusions (.05 less than p less than .10). This correlation between age of onset of depression and the tendency to be delusional is of heuristic and possibly pathogenetic interest.