Nonfatal Fall-Related Injuries Associated With Dogs and Cats—United States, 2001-2006 FREE

MMWR. 2009;58:277-281

3 tables omitted

Falls are the leading cause of nonfatal injuries in the United States. In 2006, nearly 8 million persons were treated in emergency departments (EDs) for fall injuries.¹ Pets might present a fall hazard,² but few data are available to support this supposition. To assess the incidence of fall-related injuries associated with cats and dogs, CDC analyzed data from the National Electronic Injury Surveillance System All Injury Program (NEISS-AIP) for the period 2001-2006. This report describes the results of that analysis, which showed that an estimated average of 86,629 fall injuries each year were associated with cats and dogs, for an average annual injury rate of 29.7 per 100,000 population. Nearly 88% of injuries were associated with dogs, and among persons injured, females were 2.1 times more likely to be injured than males. Prevention strategies should focus on (1) increasing public awareness of pets and pet items as fall hazards and of situations that can lead to fall injuries and (2) reinforcing American Veterinary Medical Association recommendations emphasizing obedience training for dogs.³

NEISS-AIP is operated by the U.S. Consumer Product Safety Commission (CPSC). The program collects data on initial visits for all injuries treated in EDs from a nationally representative stratified probability sample of 66 hospitals in the United States.⁴ Data on the most severe injury for each case are abstracted from medical records. Data include age, sex, location, primary diagnosis (based on a system developed by CPSC), primary part of the body injured, disposition, up to two CPSC product codes, and a two-line summary narrative describing the circumstances of the injury.

A case was defined as an unintentional, nonfatal fall injury treated in an ED during 2001-2006 with a record that either included the product code 2001 (animal-induced injury) or had “pet,” “dog,” “cat,” “puppy,” or “kitten” mentioned in the narrative. A total of 7,826 records were identified initially. The narrative for each record was reviewed, and 370 cases were excluded because the fall did not involve a dog or cat, or a pet or pet item was not directly involved in the fall (e.g., “patient jumped off a fence and fell onto a doghouse.”). The type of pet (dog or cat), location, activity, and circumstances at the time of the fall were categorized and coded based on the information in the narrative. For the analyses of dogs and cats separately, 23 cases that involved both cats and dogs were excluded; dog-related injuries were combined when cases involved one or more dogs, and cat-related injuries were combined when cases involved one or more cats.

Each case was weighted based on the inverse probability of the hospital being selected, and the weights were summed to produce national estimates. Rates per 100,000 population were calculated using U.S. Census Bureau population estimates*; 95% confidence intervals (CIs) were calculated using a direct variance estimation procedure that accounted for the sample weights and complex sampling design. Estimates based on <20 cases or with a coefficient of variation >30% were considered unstable, and the rates and CIs were not reported.

Based on 7,456 cases recorded in NEISS-AIP, an estimated average of 86,629 fall injuries associated with cats and dogs occurred in the United States each year during 2001-2006, for an average annual injury rate of 29.7 per 100,000 population. Nearly 7.5 times as many injuries involved dogs (76,223 [88.0%]) compared with cats (10,130 [11.7%]), and females were 2.1 times more likely to be injured than males. Injuries were most frequent among persons aged 0-14 years and 35-54 years. The most common injuries and the highest injury rates were for fractures and contusions/abrasions, and the highest fracture rates occurred among persons aged 75-84 years and ≥85 years. Among hospitalized patients, 79.9% were admitted for fractures.

Substantially higher injury rates were associated with dogs compared with cats. Injury rates associated with dogs and those associated with cats both increased with age, although rates of injuries associated with dogs increased more rapidly, especially after age 64 years. Rate ratios (RRs) (dogs/cats) were highest among persons aged 0-14 years (RR = 12.9) and 65-74 years (RR = 10.5) and lowest among persons aged ≥85 years (RR = 4.9). Fractures and contusions/abrasions accounted for 57.1% of the injuries among males and 55.3% of those among females.

Injuries to the extremities accounted for 51.8% of injuries associated with dogs and 47.6% of injuries associated with cats. The proportion of patients hospitalized or transferred was similar whether the injuries were associated with dogs (7.8%) or cats (10.4%). The majority of fall injuries occurred inside or in the immediate environment outside the home. Among falls involving dogs, 61.6% occurred in or around the home, and 16.4% in the street or other public place. A location was not specified for 20.3% of cases. Twenty-six percent of falls involving dogs occurred while persons were walking them, and the most frequent circumstances were falling or tripping over a dog (31.3%) and being pushed or pulled by a dog (21.2%). Falling over a pet item (e.g., a toy or food bowl) accounted for 8.8% of fall injuries. Approximately 38.7% involved other or unknown circumstances.

Most falls involving cats occurred at home (85.7%). Approximately 11.7% of injuries occurred while persons were chasing cats. However, an activity was not specified in 62.1% of cases. The most frequent circumstances were falling or tripping over a cat (66.4%.); 29.2% involved other or unknown circumstances.

JA Stevens, PhD, SL Teh, Div of Unintentional Injury Prevention, T Haileyesus, MS, Office of Statistics and Programming, National Center for Injury Prevention and Control, CDC.

In 2006, persons in approximately 43 million U.S. households owned dogs, and persons in 37.5 million households owned cats⁵; nearly 64% of households with pets had more than one pet. With the exception of one small study,² falls associated with pets have not been addressed previously in the scientific literature. This report provides the first national estimates of fall injuries associated with cats and dogs and supports anecdotal evidence that pets present a fall hazard. The findings indicate that, in 2006, cats and dogs were associated with approximately 1% of the estimated 8 million fall injuries treated in EDs¹ and affected persons of all ages. Walking dogs and chasing pets were associated with the greatest number of injuries, although details about the circumstances surrounding these falls were limited. The development of more effective prevention strategies will require more information about the risks for fall injury associated with specific pets (including size and breed), and pet-human interactions.

The analysis showed that the highest rates of injuries occurred among persons aged ≥75 years, and the most common diagnosis was fracture. Although no specific information was available on the rate of hip fracture, such fractures would be among the most serious injuries. Among older adults, hip fractures can result in serious health consequences, such as long-term functional impairments, nursing home admission, and increased mortality.⁶

The findings in this report are subject to at least four limitations. First, the number of injuries likely was underestimated because the data included only injuries treated in EDs. The study did not include injuries treated in physician offices, in other outpatient settings, or at home, or injuries that did not receive medical attention. Second, the amount of information about the location, activity, and circumstances of the falls was incomplete (e.g., activity was unknown in 46.1% of dog-related injuries and 62.1% of cat-related injuries), so only limited conclusions can be drawn on the basis of these data. Third, information provided about the breed or size of dog rarely was available. Finally, NEISS-AIP was designed to provide only national estimates and cannot provide state or local estimates.

Dog and cat ownership is increasing in the United States in concert with a rising population of older persons, in whom injuries might have the greatest health consequences. Prevention measures for fall injuries should be balanced against the known health benefits of pet ownership.⁵ The likelihood of pet-related falls can be reduced by (1) raising public awareness that certain situations or activities, such as walking dogs and chasing pets, can lead to falls; (2) increasing recognition that pets and pet items can cause falls; and (3) reinforcing American Veterinary Medical Association recommendations emphasizing obedience training for dogs³ to minimize behaviors associated with falls (e.g., pushing or pulling).

REFERENCES

6 Available.

*Available at http://www.cdc.gov/nchs/about/major/dvs/popbridge/popbridge.htm.