Opioids are most commonly associated with fatal outcomes while self-poisoning with CVD drugs has increased threefold in a quarter-century
A 26-year cohort study of all adult poisoning patients admitted to the Hunter Area Toxicology Service, inclusive of the greater Newcastle region of NSW, has found unintentional poisoning increases with age.
Of the 17,276 admissions over the time period, 626 patients (3.6%) were at least 65 years old, according to research published in the Medical Journal of Australia.
While most self-poisoning by people aged 65 or more who were admitted between 1987 and 2012 was intentional (80% of admissions), the proportion of unintentional poisonings increased with age (P < 0.001), with the proportion more than twice as great among the oldest patients as in the 65-74-year age group.
Those aged 65 and over were also more severely affected by self-poisoning, with mortality rates, ICU admission and length of stay all greater for older patients.
Declining cognitive function can be associated with unintentional overdose in older people, suggest the authors from the University of Queensland and University of Newcastle.
Multiple comorbidities and frailty may exacerbate the toxicity of these agents and hamper recovery from self-poisoning, they add.
Benzodiazepines (24%) were the most commonly ingested drugs by older patients, but opioids were the most frequently taken drugs in fatal cases.
“The rising proportion of opioid overdoses in this group is worrying, and may reflect the increasing use of these agents, particularly for the treatment of non-malignant pain,” say the researchers.
While paracetamol was the second most commonly ingested drug in poisonings, the proportion has remained constant over time and there were no fatalities, which the authors explain is probably due to the availability of the “highly effective” antidote, N-acetylcysteine.
Toxic ingestion of cardiovascular drugs increased threefold over the 26 years, and about one-third were unintentional or iatrogenic.
Meanwhile, recreational drugs were implicated in the admission of four older patients (0.6%), compared with 7.8% of those younger than 65.
With regards to intentional self-poisoning, stressors such as failing health, the death of a spouse, family discord and loneliness, as well as suicidality and depression, may contribute.
The authors point out that the Hunter Area Toxicology Service database does not capture the number of people who died outside hospital nor those with less severe poisonings who visited their GP rather than presenting to an emergency department.