MEDICAL MATTERS: Following a recent visit from some older relatives, I have been reflecting on changes that accompany our passage through the seven ages of man. Those whom you first met when you were a child and who took responsibility for you and your welfare, while maintaining their relative independence, may have become a little more frail and restricted in their activities and their horizons.
Just as we need to adjust to the changing balance in our relationships with older people, the health service must respond to their particular needs. The speciality of geriatric medicine, or medicine for the elderly, was born following the pioneering work of Dr Marjory Warren during the middle of the 20th century.
The speciality initially came into being because there was a need for doctors to supervise what were former workhouses. As a result, it suffered from a depressing and negative image during its early years. More recently, the status of the speciality has improved and departments of old age medicine are well represented in our hospitals and universities.
This is an important for two reasons. First, the number of people aged 65 and over is still rising and is predicted to reach 24 per cent of the population by 2030. The group that is increasing at the fastest rate in the Western world is the "old old" - those aged 85 years and over. In addition, older people, while developing similar diseases as younger patients, often experience a radically different group of symptoms and will have a more varied set of clinical signs for the same condition.
A recently published book - Medicine for Older Patients - as well as being of interest to healthcare professionals, provides valuable information for older patients and their carers.
Edited by Dr Richard Liston, consultant geriatrician at Tralee General Hospital, and by Dr Eamon C. Mulkerrin, consultant geriatrician at University College Hospital, Galway, the book has contributions from 20 specialists in the Republic. It covers a wide range of topics but one in particular that caught my eye was a chapter on drugs and ageing.
Following last week's column on the dangers of adverse drug reactions, this chapter, written by Cork doctors Kieran O'Connor and Denis O'Mahony, is a wake-up call for any older person in receipt of multiple types of medication. Just as our relations with older people change with time their bodies too undergo significant changes which means they are likely to develop an increased intolerance of some drugs.
The natural diminution in the function of key organs such as the heart, liver and kidneys, as well as the natural depletion of several hormones, means that older patients' response to medication can be very different.
In the US people over 60, who make up 17 per cent of the population, account for nearly 30 per cent of drug-related hospitalisations and more than half the deaths from adverse drug reactions.
Among the drugs that cause the greatest side effects in older people are sedatives. Over-sedation, confusion and falls are a common result. Older anti-depressant drugs can also bring about similar problems. Polypharmacy - the simultaneous prescribing of a large number of drugs - is common in the older population. More than 85 per cent of older people take at least one type of medication.
One of the attractive features of this book is its copious use of case histories which help to emphasise key points. The chapter on drugs and ageing has the following: "JK, a 77-year-old man with osteoarthritis and heart failure, came to see his doctor with nausea, vomiting and palpitations. He was taking the following medications: aspirin, frusemide (a water tablet), ibuprofen (a non steroidal anti-inflammatory drug - NSAID) and two drugs for his heart, digoxin and ramipril."
Blood tests show he has a low potassium and sodium level and an elevated urea, a sign that his kidney function is failing. He has also lost 2kg in the previous week. "This case shows how one patient can present with a number of adverse drug reactions and drug interactions," the authors note. "JK has been prescribed a NSAID for osteoarthritis leading to fluid retention which has exacerbated his heart failure... NSAIDs also contribute to his renal impairment (kidney failure) particularly since he is also on ramipril, an ACE inhibitor. He may also have digoxin toxicity."
Following a thorough assessment JK's digoxin is withheld. Because the simultaneous use of NSAIDs and ACE Inhibitors is "contraindicated", this combination is also contributing to his symptoms. All his other medications are temporarily stopped while he is treated with intravenous fluids and potassium replacement. Ten days later he is discharged home with lower doses of frusemide and ramipril and with his medication-induced kidney and heart failure reversed.
The multitude of case histories dotted throughout the book render it reader-friendly for the non-medic. It would make a good read for carers, relatives and older people themselves.
• Muiris Houston is pleased to hear from readers at mhouston@irish-times.ie but regrets he cannot answer individual queries.
• Medicine for Older Patients is published by Eireann Healthcare Publications. Price €34:95 (ISBN 0-9541493-2-7) Available from most book shops or by mail order from Dr Richard Liston, Tralee General Hospital, Tralee, Co Kerry.