According to a new study in the journal Age and Ageing, a significant proportion of patients over 70 remain on antihypertensive medication despite having low blood pressure. This, the study argues, has a significant effect on increased mortality rates and admissions to hospital.
After analysing results of 11,167 patients over 70 years old, the researchers from CHSS at the University of Kent and East Kent Hospitals found that hypotension was independently associated with increased morality and hospital admissions. Of the 1899 people with some degree of low blood pressure, 1246 of these were on antihypertensive medication (lowering blood pressure). Lead author Professor Chris Farmer, explained:
"Treating hypertension in old age reduces strokes and other cardiovascular events. However in elderly patients with multiple risks, there is a trade-off between using antihypertensives to reduce the risk of future disease and increased risk due to adverse effects of medication."
"Once medication is initiated", Professor Farmer continued, "it is not always regularly reviewed to adjust for physiological changes associated with ageing and the effects of additional drugs."
When analysing the patients with the lowest level blood pressure (less than 100mmHg), almost 70 per cent were taking antihypertensives. The number they were taking was not significantly associated with mortality. The study did stress that it is not known whether the hypotension was the result of a severe illness which was the primary cause of hospital admissions or whether it was the hypotension itself. Despite this, the authors argued the importance of their finding: a clinically significant proportion of elderly people on antihypertensive drugs are hypotensive.
The authors concluded that the consequences of hypotension due to drugs are potentially costly to the NHS and have a negative effect on the quality of life of older patients. They have recommended in the paper that treatment must be regularly reviewed in order to balance the risk and benefits, and that further trials are needed to establish which older people are most likely to derive more benefit than harm from treatment.
Oxford University Press (OUP)