Nonfatal Bathroom Injuries Among Persons Aged ≥15 Years—United States, 2008 FREE

MMWR. 2011;60:729-733

2 tables omitted

In 2008, approximately 21.8 million persons aged ≥15 years sustained nonfatal, unintentional injuries,¹ resulting in approximately $67.3 billion in lifetime medical costs.² Information about where injuries occur is limited, but bathrooms commonly are believed to be a particularly hazardous location.³ To investigate this assumption, CDC analyzed data from a nationally representative sample of emergency departments (EDs) to describe the incidence and circumstances of nonfatal injuries in bathrooms (in any setting) among persons aged ≥15 years in the United States. This report describes the results of that investigation, which found that, based on 3,339 cases documented in the 2008 National Electronic Surveillance System All Injury Program (NEISS-AIP) database, an estimated 234,094 nonfatal bathroom injuries were treated in U.S. EDs. Injury rates increased with age, and most injuries (81.1%) were caused by falls. All persons, but especially older adults, should be aware of bathroom activities that are associated with a high risk for injury and of environmental modifications that might reduce that risk.

This study used 2008 data from a nationally representative stratified probability sample of 62 hospital EDs in the United States, available from NEISS-AIP, which collects data on initial visits for all injuries treated in these EDs. Trained NEISS-AIP coders abstract information from the ED medical record about the principal diagnosis for each case, which, if more than one injury is recorded, usually is the most severe. Data include age, sex, primary diagnosis (using a system developed by the Consumer Product Safety Commission [CPSC] that is compatible with but does not include International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] codes), primary part of the body injured, disposition at discharge, up to two CPSC product codes* (determined by the coders based on the account of the injury in the medical record), and a two-line summary narrative describing the circumstances of the injury.

CDC examined unintentional, nonfatal bathroom injuries among persons aged ≥15 years and identified the types of injuries, most common locations within the bathroom, and the precipitating events. Potentially eligible cases were among persons aged ≥15 years whose NEISS-AIP record contained a CPSC product code for products associated with bathrooms or whose case narrative included the words “bath,” “shower,” “tub,” “commode,” “toilet,” or “potty chair.”

The screening procedure identified 3,635 potential cases. After review, 296 were excluded because the injuries were work-related, involved repairing or remodeling the bathroom, were not related to bathroom products or activities, or could not be determined to have occurred in the bathroom, leaving 3,339 cases for analysis.

Based on the narrative for each case, two additional variables were coded: the location in the bathroom where the injury occurred (e.g., bathtub, shower, or sink) and the precipitating event (e.g., bathing or showering, slipped, sitting down, or using the toilet). “Bathing or showering” did not include slipping in the tub or shower; these events were coded as “slipped.” However, events such as “slipped while getting into (or out of) the shower” were coded as “getting into (or out of) the tub or shower” because these activities were considered a priori to be particularly hazardous.

Data were weighted to represent the total number of initial injury-related visits each year in the United States, and estimates were adjusted for hospital nonresponse and changes in the number of ED visits from year to year. The final weights of the cases were summed to produce national estimates. Rates per 100,000 population were calculated using U.S. Census Bureau population estimates for 2008; 95% confidence intervals (CIs) were calculated using statistical software that accounted for the sample weights and the complex sampling design. Estimates based on <20 cases or with coefficients of variation >30% were considered unstable, and the rates and CIs are not reported. P-values of ≤0.05 were considered statistically significant.

In 2008, an estimated 234,094 nonfatal bathroom injuries among persons aged ≥15 years were treated in U.S. EDs, for an injury rate of 96.4 per 100,000 population. The rate for women was 121.2 per 100,000 and was 72% higher than the rate for men (70.4 per 100,000) (Table 1). Although approximately the same number of cases occurred in each 10-year age group, injury rates increased with age. Falls were the most common primary cause of injury (81.1%), and the most frequent diagnosis was contusions or abrasions (29.3%). The head or neck was the most common primary part of the body injured (31.2%). Most patients (84.9%) were treated and released from the ED; 13.7% were treated in the ED and subsequently hospitalized.

The highest rates were for injuries that occurred in or around the tub or shower (65.8 per 100,000) and injuries that happened on or near the toilet (22.5 per 100,000) (Table 2). The precipitating events in 37.3% of injuries were bathing (excluding slipping while bathing), showering, or getting out of the tub or shower; only 2.2% occurred while getting into the tub or shower. The precipitating event for 17.3% of injuries was slipping, which included slipping while bathing; 14.1% occurred when standing up from, sitting down on, or using the toilet; and 5.5% were attributed to an antecedent loss of consciousness.

Injury rates increased with age, especially those that occurred on or near the toilet, which increased from 4.1 per 100,000 among persons aged 15-24 years to 266.6 among persons aged ≥85 years. Injuries occurring in or around the tub or shower also increased markedly, from 49.7 per 100,000 among persons aged 15-24 years to 200.2 among persons aged ≥85 years. Within each 10-year age category, the relative proportion of injuries differed by location within the bathroom. The proportion of injuries in or around the tub or shower was highest among persons aged 15-24 years (84.5%) and lowest among persons aged ≥85 years (38.9%), whereas the proportion of injuries that happened on or near the toilet was lowest among persons aged 15-24 years (7.0%) and highest among persons aged ≥85 years (51.7%).

Within age categories, the relative proportion of injuries also differed by precipitating event (or activity). Among persons aged 15-24 years, the percentage of injuries that occurred while bathing or showering was 34.3% (rate 20.2 per 100,000), whereas among persons aged ≥85 years, the percentage of injuries occurring while bathing or showering was 15.5% (rate 79.9). In contrast, the proportion of injuries that occurred when getting on, off, or using the toilet was lowest among persons aged 15-24 years (2.0%) and increased with age, reaching 19.3% among persons aged 65-74 years, 26.9% among persons aged 75-84 years, and 36.9% among persons aged ≥85 years. Injury rates were 1.2, 21.6, 64.8, and 190.1 per 100,000 for age groups 15-24, 65-74, 75-84, and ≥85 years, respectively.

The injury rate associated with syncope or loss of consciousness was low. For most age groups, it accounted for fewer than 7.0% of injuries and ranged from 3.6% among persons aged 25-34 years to 9.4% among persons aged 15-24 years.

The leading injury diagnoses were contusions or abrasions (29.3%), strain or sprain (19.6%), and fracture (17.4%). The age-specific rate for contusions or abrasions increased from 13.5 per 100,000 (aged 15-24 years) to 157.9 (aged ≥85 years), whereas rates for strains and sprains increased only slightly with age. In contrast, the fracture rate increased markedly, from 5.8 per 100,000 (aged 25-34 years) to 165.6 (aged ≥85 years). Hospitalization rates, which could be calculated only for persons aged ≥55 years, followed a similar pattern (lowest among persons aged 55-64 years [11.9 per 100,000] and highest among persons aged ≥85 years [197.4]).

Judy A. Stevens, PhD, Elizabeth N. Haas, Div of Unintentional Injury Prevention; Tadesse Haileyesus, MS, Office of Program and Statistics, National Center for Injury Prevention and Control, CDC. Corresponding contributor: Judy A. Stevens, CDC, jas2@cdc.gov, 770-488-4649.

This is the first report to describe the incidence and circumstances of nonfatal bathroom injuries among persons aged ≥15 years in the United States. In 2008, an estimated 234,094 unintentional nonfatal injuries among persons aged ≥15 years occurred in bathrooms, for an injury rate of 96.4 per 100,000 population. This represented approximately 1% of the nearly 22 million nonfatal injuries among this age group treated in EDs that year. However, the impact was greater among persons aged ≥65 years. Among this population, bathroom injuries represented 2.5% of all unintentional injuries.

Injury rates were higher in women. Studies consistently have shown that women are at higher risk than men for falling and for sustaining fall-related injuries.⁴ This difference might be related to gender differences in physical activity, lower-body strength, bone mass, circumstances surrounding the fall, or greater willingness to seek medical treatment.⁵

Approximately 80% of all bathroom injuries were caused by falls, with the highest injury rates in the oldest age groups. For adults aged ≥65 years, falls often cause serious injuries, such as hip fractures, attributed in part to osteoporosis, a metabolic disease that makes bones porous and susceptible to fracture.⁶ This study found that older adults had the highest fracture rates and were hospitalized most often.

For all ages, the most hazardous activities were bathing, showering, or getting out of the tub or shower. Approximately two thirds of all injuries occurred in the tub or shower, and approximately half were precipitated by bathing or showering, slipping, or getting out of the tub or shower. Only 2% of injuries occurred while getting into the tub or shower, when bathroom fixtures and floors likely would be less slippery. According to the Home Safety Council's 2004 The State of Home Safety in America report,⁷ 63% of U.S. homes used bathtub mats or nonskid strips to help reduce bathtub falls, but only 19% of homes had grab bars. The study described in this report included all settings; however, bathrooms in assisted-living facilities and nursing homes likely would have grab bars, whereas private homes likely would not.

Injuries associated with getting into and out of the tub or shower occurred among persons of all ages, suggesting that adding grab bars both inside and outside the tub or shower might help prevent bathroom injuries to all household residents. Overall, approximately 14% of injuries were associated with standing up from, sitting down on, or using the toilet, but among persons aged ≥65 years, the proportion ranged from 19% to 37%. Although less than 3% of older adult injuries were attributed to loss of consciousness, the injuries among persons aged ≥65 years associated with using the toilet might be attributed in part to vasovagal syncope. This condition is a common cause of fainting and can be brought about by urinating, having a bowel movement, or abdominal straining.⁸ Standing after prolonged sitting also can result in postural hypotension, a sudden drop in blood pressure that causes light-headedness or dizziness. Postural hypotension, which also might be caused by dehydration or as a side effect of medication, is a known risk factor for falls.⁶ Preventing falls and subsequent injuries in this vulnerable older population is critical. Persons with postural hypotension can reduce symptoms by standing up slowly; installing grab bars near the toilet would provide an additional measure of safety. Effective fall prevention strategies for older adults include exercises to improve strength and balance and medication review and modification by a health-care provider.⁹

Loss of consciousness was reported as a precipitating event by 9.4% of persons aged 15-24 years. Although alcohol use is poorly documented in NEISS-AIP, a New Zealand study reported that approximately 20% of unintentional falls among working-age adults were attributable to alcohol consumption.¹⁰ Better data are needed to clarify the contribution of alcohol use to bathroom injuries among various age groups.

The findings in this report are subject to at least five limitations. First, this study included only injuries treated in EDs and not injuries treated in physicians' offices or other outpatient settings or injuries that did not receive medical attention. However, the majority of serious injuries probably were included because most major injuries are treated in EDs. Second, information about the circumstances surrounding the injury was limited to the two-line narrative, which did not always contain complete information. Nearly 17% of injuries could not be attributed to a specific precipitating event based on data in the NEISS-AIP record. Third, injuries that proved fatal before or in the ED were excluded because NEISS-AIP does not provide detailed information about fatal injuries. However, only approximately 0.5% of unintentional injuries result in death.¹ Fourth, NEISS-AIP included only one injury (generally the most severe) and one part of the body injured. Some underreporting might occur if there were multiple injuries. Finally, because ICD-9-CM diagnosis codes were not included in the medical record at the time these data were collected, specific injuries (e.g., hip fracture, spinal cord injury, or traumatic brain injury) could not be identified.

These findings suggest that all adults, especially older adults, their caregivers, and their family members, should be educated about activities in the bathroom that more frequently result in injury, notably getting out of tubs and showers and getting on and off toilets. Injuries might be reduced through environmental modifications, such as putting non-slip strips in the tub or shower and adding grab bars inside and outside the tub or shower to reduce falls, and installing grab bars next to the toilet for added support if needed. However, more research is needed to determine how effective grab bars and other environmental modifications might be in preventing bathroom injuries. Increasing awareness of potentially hazardous activities in the bathroom, combined with these simple environmental changes, could benefit all household residents by decreasing the risk for injury.

Each year, approximately 2.2 million persons aged ≥15 years sustain unintentional, nonfatal injuries, costing approximately $67.3 billion in lifetime medical costs. Although only limited information is available regarding where injuries occur, bathrooms are commonly believed to be a hazardous location.

What is added by this report?

In 2008, an estimated 234,094 bathroom injuries (or 1% of all unintentional injuries among persons aged ≥15 years) were treated in hospital emergency departments. The rate of unintentional injuries that occurred in bathrooms increased with age and was highest for persons aged ≥85 years. These results suggest that bathrooms tend to be most hazardous for persons in the oldest age groups.

What are the implications for public health practice?

Persons in all age categories sustained bathroom injuries, especially when bathing or showering or when getting out of the tub or shower. Raising awareness about potentially hazardous activities and making a number of simple environmental changes, such as installing grab bars inside and outside the tub or shower and next to toilets, could benefit all household residents by decreasing the risk for injury.

*Product codes included bathtub or shower enclosures (0609, 0610, 4030); bathtubs or showers (0611); draperies, curtains, or shower curtains (0617); sinks (0648); toilets (including adult potty chairs) (0649); towel racks or bars (0657); faucets or spigots (0699); and potty chairs or training seats (1535).