Senile dementia is an exaggeration of the mental changes occurring in old age and due to further changes in the brain from vascular disease or toxic influences. It varies much in its features; some patients are maniacal, others depressed and melancholic, some feeble, some delusional, and a few immoral. The senile mania may be mainly nocturnal and was compared by Clouston[210] to the night delirium of a febrile neurotic child; it may pass into dementia. Of the melancholic group in which suicide may occur Clouston found that 30 per cent recovered.
Senile paraplegia may be divided into four etiological groups: (1) The functional dysbasias or pseudo-paraplegias described by Marie and Léri,[211] which in general terms resemble those met with during adult life, but the varieties are less distinct in the old. Quesnel[212] recognizes three groups of functional disturbance of walking in old people: (a) the slight and usually curable, (b) severe functional disturbance depending essentially on the mental state of the patient, and (c) the organo-functional in which a bony, articular, or nervous lesion is present; thus confinement to bed for a fracture may cause a functional paraplegia. (2) Spastic paraplegia due to sclerosis in the lateral and posterior columns of the spinal cord; the influence of arteriosclerosis, as advocated by Oppenheim, has been the subject of some debate, and Lejonne and Lhermitte point out that the nervous lesions are not necessarily perivascular and that there is a want of proportion between the vascular and the nervous changes. (3) Paraplegia of cerebral origin with descending degeneration in the cord and mental deterioration. (4) Paraplegia from muscular fibrosis and contracture, the central nervous system being intact.
From the presence of emphysema bronchitis is prone to occur in the old. Lobar pneumonia and bronchopneumonia. Lobar pneumonia has always been considered the great enemy of the aged; it is often latent, and may be found after sudden death and in persons supposed to have died of old age, because they were walking about or complained not at all or only of trivial symptoms. In spite of Charcot’s[213] considered opinion to the contrary, it is probable that pneumonia has been often used to describe what was really bronchopneumonia. For Roussy and Leroux[214] found that among 300 necropsies at the Hospice Paul Brousse there were 164 cases, or 55 per cent, of bronchopneumonia and only 4 cases, or 1·4 per cent, of lobar pneumonia. The bronchopneumonic areas are triangular with the base towards the pleural surface, and indeed are infarcts, due to pre-existing endarteritis obliterans which disposes to secondary infection. In 110 out of the 164 cases of bronchopneumonia there was arterial thrombosis, which was of older date than the infected areas of infarction and bronchopneumonia.
Senile tuberculosis, contrary to what has sometimes been stated, is fairly common though it is often latent; a patient with pulmonary tuberculosis may have little or no cough, expectoration, fever, or night sweats, and the physical signs, if present, may be regarded as those of bronchitis and emphysema or bronchiectasis, unless the sputum is available and examined for bacilli. Such unrecognized cases are an obvious danger in institutions, and it may be added that hereditary disposition plays a much less important part in the aged than in early life. Senile tuberculosis, however, is usually either a persistence of that infection or a recrudescence of quiescent infection, and is seldom primary. The disease may be chronic or acute, and either local or generalized.
The senile heart has attracted much attention, and myocardial degeneration and fibrosis due to past infections or to coronary arteriosclerosis are extremely common. The myocardial change is of great importance in reducing the reserve power of the heart, so that cardiac failure is prone to supervene in acute infections, such as influenzal pneumonia. Chronic valvulitis akin to and associated with arteriosclerosis is common; the mitral valve is often affected and incompetent, with a loud systolic murmur at the apex which is displaced outwards; but the most characteristic lesion of advanced years is pure aortic stenosis; this is commonly regarded as part of the arteriosclerotic process in the aorta, but, as I have often noticed, the aorta may be remarkably healthy and even thinner than usual in old people with extensive calcification of the valves reducing the aortic orifice to a chink; it has indeed been thought that such stenosis of the aortic valves may protect the aorta from strain and so from arteriosclerosis. Although involvement of the bundle of His giving rise to the symptom complex of Stokes-Adams disease, and angina pectoris may complicate aortic stenosis, the presence of this valvular defect is compatible with remarkable prolongation of life. This may be due to the more placid life of these old patients, as is suggested by Sir Clifford Allbutt,[215] who regards aortic stenosis as more unfavourable in persons under 55 years of age than in their elders.
Aneurysm of the large arteries is rare in the aged, although arteriosclerosis is common. Diffuse dilatation especially of the arch of the aorta and of the common iliacs is not infrequent, and occasionally latent saccular aneurysms are present. In rare instances large abdominal aneurysms causing pain or remaining latent until rupture occurs are reported. Among 112 abdominal aneurysms collected by Nunneley[216] 15 were over 50 years of age; these figures included 32 from St. George’s Hospital, three of them being over 65 years of age. Miliary aneurysms are of course extremely common in the subjects of cerebral haemorrhage.
Spasm, especially of arteriosclerotic vessels, may be responsible for attacks of giddiness or faintness, particularly on exertion, and there may be some doubt whether such symptoms are the outcome of cerebral anaemia or of cardiac insufficiency. Frequent transient attacks of aphasia or paralysis, due to spasm of arteriosclerotic middle cerebral arteries, may occur in patients with high blood pressure (Peabody,[217] Osler[218]).
Varicosity either localized, like aneurysms, or throughout the length of veins, are common, especially in the lower limbs of women who have borne children and done much standing; this condition disposes to varicose ulcers in the lower third of the leg, and to acute phlebitis. As pointed out by Trousseau, who was an illustration of his own dictum, venous thrombosis may occur in the course of intra-abdominal malignant disease.
Though dyspepsia of adult life often diminishes or passes away in the more tranquil conditions of old age, it is common; Fenwick[219] estimated that it occurred in 21 per cent of the population over the age of 65. Oral sepsis may be responsible for chronic gastritis and much debility in the old. Constipation often comes on after 60 and is mainly due to atonic dilatation and failure of peristalsis in the colon, though diminished secretion of mucus may play a part. Prostatic enlargement has been thought to interfere with peristalsis (Hollis[220]), and in women large fibromyomas of the uterus may have this effect. Gerontal constipation is usually more troublesome in women than in men. Faecal accumulation in the rectum is a frequent cause, especially in bed-ridden subjects, of what they describe as diarrhoea, the real significance of which may be easily overlooked unless digital examination of the rectum is undertaken. The pecten band of fibrous tissue arising in the submucosa of the pecten, inside the external sphincter, narrows the anal orifice and so prevents complete evacuation of the rectum and diminishes the size of the faeces which are generally voided in short pieces. It is usually, but not always, associated with internal piles and due to the attendant congestion. W. E. Miles,[221] who described the pecten band, tells me that it may be regarded as a pathological development of advancing years, and that he has found that it may so reduce the anal orifice in the elderly that it is with difficulty the little finger can be introduced. Pruritus ani, due to piles and local congestion, is not uncommon in the aged.
Piles are common in the aged and are related to the frequency of constipation. Like other diseases, they do not give rise to discomfort so soon or so forcibly as in younger persons. From muscular atrophy hernia, umbilical in both sexes, in men inguinal and in women femoral, is prone to occur.