Sex Differences in Poisonings Among Older Adults: An Analysis of the Toxicology Investigators Consortium (ToxIC) Registry, 2010 to 2016

Abstract

PURPOSE: Adults aged > 65 years are susceptible to intentional and unintentional poisoning, with contributing factors that include polypharmacy, comorbidity, susceptibility to medication error, and gaps in research. Although toxicologists are often tasked with managing and preventing poisoning among older adults, little is known about sex differences in these poisonings. The aim of this study was to review sex differences in poisonings among older adults managed at the bedside by medical toxicologists. METHODS: All case subjects aged > 65 years in the Toxicology Investigators Consortium (ToxIC) registry between January 2010 and December 2016 were reviewed. Data included reasons for exposure and consultation, exposure agents and routes, presenting clinical findings, and treatment provided. Cases missing age, sex, or primary reason for toxicology consultation data were excluded. We used chi(2) tests to assess differences in distribution of study variables according to participant sex. FINDINGS: Among 51,441 total registry cases, 542 (1.05%) were excluded because of missing data. Among the remaining 50,899 cases, 2930 (5.8%) were included for age > 65 years; 52.3% of older adults were female. Race was missing or unknown for 49.2% of cases. Adverse drug reactions were more commonly encountered in female subjects than in their male counterparts (9.6% vs 6.4%; P=0.001). No statistically significant sex differences were observed for total numbers of intentional, unintentional pharmaceutical, and nonpharmaceutical exposures. The most common medications involved were cardiovascular (16.8%) and analgesics/opioids (14.8%). Female subjects were more likely than male subjects to be evaluated by a toxicologist for cardiovascular medications (18.7% vs 14.7%; P=0.004) and analgesics/opioids (17.6% vs 11.8%; P < 0.001). Male subjects were more likely than female subjects to be evaluated for ethanol toxicity (7.4% vs 1%; P < 0.001) and for envenomations (4.2% vs 1.8%; P < 0.001). The most common route of exposure was oral ingestion (81.3%). Signs/symptoms were noted in 54.8% of cases, with the most common abnormal vital sign being bradycardia (17.2%). Pharmacologic support was the most common intervention and was more common in male subjects than in female subjects (17.7% vs 12.3%; P < 0.001). Deaths were reported in 38 female subjects (2.45%) and 46 male subjects (3.34%); there was no statistically significant difference in death rate according to sex (P=0.148). IMPLICATIONS: Older female adults were more commonly evaluated by a medical toxicologist for an adverse drug reaction than older male adults. Female patients were more likely than male patients to be evaluated for poisoning related to analgesic/opioids and cardiovascular medications, and older male patients more frequently received pharmacologic support than older female patients. No significant sex differences were observed in numbers of toxicology consultations for intentional, unintentional pharmaceutical, and nonpharmaceutical exposures.