A Clinical Overview Of Diseases In Aging (Geriatrics) With Focus On Morphological Changes
A General Overview
Elderly people behave differently from others in respect to predisposition to disease, general resistance against infections and response to drugs. The discipline of geriatrics deals with the diagnosis and treatment of persons aged 65 years and above. The age of 65 as the commencement of senescence has been accepted arbitrarily. During senescence, all illnesses are accompanied by a higher mortality than when occurring in younger age groups. A better functional definition of senescence will be as the period when there is commencement of loss of vigour, skin changes of old age, slowed activity of the musculoskeletal system and onset of deterioration of mental functions. The lifespan of man is increasing all over the world. In India for instance, over 5.5% of the population is above the age of 60 years. The maximum lifespan has not changed despite an increase in the average lifespan.
The changes in structure and function occurring in persons after the attainment of sexual maturity constitute aging. With advancing age, the adaptability to overcome environmental or internal challenges decreases and the probability of death increases. Tissues differ in their behaviour during aging. Visual and auditory functions start deteriorating even in the third decade of life. The rate of deterioration in other organ systems depends to a great deal upon other factors like coexistent diseases, diet, physical exercise and to a great deal on hereditary factors. The present explanations for aging process are not fully satisfactory though many have been put forward.
Cancer In Geriatrics
Morphological Changes Of Aging
Cellular changes: The total number of cells come down in parenchymal organs such as brain, liver and heart. Cell sizes and staining properties become irregular and many binucleate cells appear. The water content of collagen comes down and cross- linkages increase, rendering it increasingly rigid and inflexible. This affects mobility adversely. Ellastin also shows degenerative changes.
Alterations In Organs
Skin: The skin becomes hyperkeratotic, atrophic and wrinkled. Sweat glands and sebaceous glands diminish. Greying of hair occurs because of the progressively smaller amounts of dopa-oxidase and tyrosinase in hair follicles, both of which are required for synthesis of melanin. Greying of the hair shows a strong genetic predisposition (autosomal dominant) and in the majority of people 50% of the hairs are grey above the age of 50 irrespective of the sex and hair colour.
Heart And Blood Vessels: Ischemic and hypertensive diseases often supervene as age advances and, therefore, it is difficult to separate these changes from purely aging process. Above the age of 75 years interstitial fibrosis and fatty infiltration of myocardium develop, even in the absence of any concomitant disease. Lipofuhsin accumulates in the myocardium. Endocardium and valves are thickened. Amyloidosis may develop. Loss of elasticity leads to widening and tortuosity of the Aorta. Atherosclerosis accelerates these changes.
Lymphatic Organs: The spleen undergoes atrophy. There is increase in the number of plasma cells. Above the age of 70 years serum globulins are increased and amyloidosis may develop. This form of amyloidosis may affect the heart, islets of langerhans, peripheral and autonomic nerves and brain. There is generalized impairment of immune processes and, therefore, infections take a fatal turn.
The risk of cancer increases with age and neoplasia accounts for 20% of the total deaths. Atherosclerosis, hypertension, and cancer together cause the majority of deaths. Invariably multiple diseases coexist in the elderly patients and diagnosis is often difficult. The symptomatology is atypical.
© 2014 Funom Theophilus Makama