2.—Exciting Causes.
To ascertain the exciting causes of epileptic seizures with exactitude is usually a matter of very great difficulty. It is simple enough when the results directly follow the cause; but this is not commonly the case. If, for example, a man, after a blow on the head (having been previously in good health) becomes suddenly seized with epileptic attacks within a few hours or days of the accident, we may fairly assume that the injury has originated or developed his illness. But should the seizure not supervene for some months or years afterwards, the external wound having in the meantime completely recovered, there remains on this question a considerable element of doubt. In the same way a patient often attributes the attacks to a fright which may have occurred weeks or months before they began; yet great care should be taken in accepting such a statement: on the other hand, it should not be utterly ignored. Again, if a person develops epilepsy after severe and prolonged domestic trouble or affliction, how are we accurately to determine the relation between the two? These difficulties render an exact method of ascertaining the exciting causes almost impossible, and this can only be approximated by a careful consideration of the entire history and circumstances of the case. Taking these into consideration, the following statements have been drawn up, in which only those conditions are recorded, where from a review of the whole case a reasonable relation was found to exist between cause and effect.
In a hundred unselected cases of epilepsy there were—
| No apparent exciting cause in | 43 per cent. |
| Possible exciting cause in | 57 per cent. |
Of the cases where a possible exciting cause was present, the following is an analysis:—
| Blow or injury to head in | 28.1 per cent. |
| Uterine disorder in | 22.8 per cent. |
| Domestic trouble in | 15.7 per cent. |
| Disease of the nervous system in | 8.7 per cent. |
| Fright in | 5.2 per cent. |
| Depression in | 5.2 per cent. |
| Pregnancy in | 5.2 per cent. |
| Mental strain in | 3.5 per cent. |
| Sunstroke in | 3.5 per cent. |
| Emotion in | 1.7 per cent. |
Thus, in no fewer than 16 per cent. of the total number of cases, and 28.1 of those in which a possible exciting cause was present, did epileptic seizures follow injuries to the head. Of the cases recorded under uterine disorders, it must be stated that these conditions were as much the accompaniments as the cause of epilepsy, the relations between the two being as follows:—
| Attacks occurring at menstrual periods in | 61.5 per cent. |
| Attacks associated with irregular menstruation in | 30.7 per cent. |
| Attacks associated with uterine disease in | 7.6 per cent. |
An attempt was made in twenty-two cases to ascertain whether, in women, the age at which the epileptic attacks began had any relation to the period at which the catamenia commenced, with the following results:—
| Average age at which attacks began | 14.6 years |
| Average age at which catamenia began | 14.6 years |