The aetiological role of physical disability in affective disorder of old age has been studied in 231 consecutive admissions aged 60 and over. The incidence of acute and chronic illness and serious sensory defect was compared in those whose first attack had occurred before 60 (120 cases) and those with a first breakdown after 60 (111 cases).
Physical illness and/or sensory disability was present in 62 per cent. of the men and 51 per cent. of the women in the whole material.
In about one-sixth of all cases acute physical stress (illness, operation, or trauma) immediately preceded the onset of affective breakdown. But in the group with onset after 60, the physical condition was more often an exacerbation of, or consisted in operative treatment for, underlying chronic disease, from which recovery was incomplete.
Chronic physical illness was found in 40 per cent. Nearly every kind of illness, including sensory defect, was commoner in the group with late onset.
These results suggest that more severe stress is necessary to cause affective breakdown in those individuals who have been resistant during most of life. In general, exogenous may be more important than constitutional factors in this group, where as broadly speaking the reverse may be true of those with earlier breakdown.
The difference between groups of late and early onset is more marked and consistent for males. Physical illness is probably more important in the causation of affective psychosis commencing in old age in men; this may contribute to the higher proportion of males in the group of late onset.
Thorough physical investigation is indicated in all cases of affective disorder commencing in old age particularly in men. Serious organic disease is often present and underlies hypochondriacal complaints.