Services like Uber, Lyft reduce trauma visits, DUIs in Houston area

When going out for a drink, leave your car keys at home—the introduction of rideshare services to the Houston area led to a significant decline in rates of trauma related to motor vehicle crashes (MVCs), along with fewer convictions for driving under the influence (DUIs), according to results from a multicenter cohort study in Texas.

The advent of ridesharing services, such as Uber and Lyft, seemed to offer a promising alternative to impaired driving for people who choose to go out for a few drinks; however, research on ridesharing outcomes is limited, and the research that does exist is contradictory—some studies, for example, have found that ridesharing reduces incidence of alcohol-related vehicular homicide, while others concluded that it had no significant impact on drunk-driving fatalities, or even increased them.

Christopher R. Conner, MD, PhD, of McGovern Medical School at the University of Texas Health Science Center in Houston, and colleagues conducted an analysis “to quantify the change in MVC traumas and impaired driving convictions after the introduction of rideshare services,” they explained in JAMA Surgery. They performed their study in the Houston metropolitan area using data from Memorial Hermann Hospital-Texas Medical Center and Ben Taub General Hospital—both of which are level 1 trauma centers capable of providing total care for every aspect of injury, from prevention through rehabilitation—and DUI convictions from the Harris County, Texas, District Attorney’s (DAs) office.

Conner and colleagues found that, since Uber was first deployed in the Houston area in February 2014, rideshare volume had a significant negative correlation with incidence of MVC-related trauma, particularly among individuals younger than 30 years of age, as well as a substantial decrease in DUI convictions.

Their results suggested that “increased use of rideshares may be an effective means of reducing impaired driving and decreasing [the] rate of MCV traumas,” they wrote. They also noted, however, that further research will be needed to “focus on the association between demographics and socioeconomic status and ridesharing services, MVC traumas, and impaired driving in other metropolitan areas.

“The results from this study highlight the importance of ridesharing services as a potential consumer-driven, innovative solution in reducing the incidence of MVC trauma,” Adil Haider, MD, MPH, dean of the Medical College at Aga Khan University in Karachi, Pakistan, and deputy editor of JAMA Surgery, and Hamna Shahbaz, MD, of the Dean’s Clinical Research Fellowship Program at Aga Kahn University, wrote in an invited commentary accompanying the study.

They added that such studies “are extremely important in assessing the association of consumer-driven and economic-driven interventions with public health improvements. Ridesharing services have demonstrated the capacity to alter the way in which populations use road networks, thereby directly affecting road safety and public health.” In particular, they noted that beyond the realm of drunk driving, ridesharing may have dramatic implications for reducing traffic fatalities associated with sleep deprivation and medical conditions, along with increasing mobility for people with physical and/or cognitive conditions.

However, Haider and Shahbaz noted that ridesharing services will require proper regulation “so that their potential advantages are not overshadowed by their safety concerns. And, regarding the analysis by Conner et al, they added that confining the study to level 1 trauma centers makes it difficult to generalize the results—a limitation the study authors themselves acknowledged.

For their analysis, Conner and colleagues retrospectively obtained data on MVC traumas (both fatal and non-fatal) from Memorial Hermann Hospital-Texas Medical Center and Ben Taub General Hospital from January 2007 through November 2019, as well as arrest data for DUIs, including dates and locations, from the DAs office for the same period. Rideshare data was sourced directly from Uber, and a second set of rideshare data was pulled from Google Trends search volume using the search terms “Uber” and “Lyft”—Lyft Inc. did not respond to requests to provide data for the analysis.

MVC trauma data was included for all patients ages 16 years and older with mechanism of injury classified under “motor vehicle collision,” while impaired driving incidents were only included if they resulted in guilty pleas, convictions, or probation.

The final analysis consisted of 23,491 MVC traumas (mean [SD] age 37.9 [17.8] years; 14,603 male [62.1%]), 93,742 impaired driving convictions, and over 24 million Uber rides.

“Following the introduction of Uber in February 2014, MVC traumas decreased by 23.8% (from a mean [SD] of 0.26 [0.04] to 0.21 [0.06] trauma incidents per hour) during peak trauma periods (Friday and Saturday nights),” the study authors found. “The incident rate ratio of MVC traumas following Uber deployment was 0.33 (95% CI, 0.17-0.67) per 1000 indexed rides (P=0.002). Furthermore, rideshare use was associated with a significant, geographically linked reduction in impaired driving convictions between January 2014 to December 2019 (incidence rate ratio, 0.76 [95% CI, 0.73-0.78]; P<0.001).”

Conner and colleagues pointed out that the mean age of patients treated for MVC traumas significantly increased during the study period, from 37.2 years prior to the introduction of ridesharing to 39.4 years after (P<0.001), demonstrating that “the number of patients younger than 30 years with MVC traumas decreased after 2015 (from 866 patients in 2013 to 529 in 2018 [a 38.9% decrease]), while other age groups had stable incidence of MVC traumas.”

The study authors also noted that impaired driving convictions saw the greatest decrease on Fridays, Saturdays, and Sundays, and that the distribution of convictions changed geographically over the study period—before January 2014, the majority of impaired driving arrests occurred in Houston’s core, while post-2014 convictions primarily stemmed from arrests outside of the city’s core.

Study limitations included confining the analysis to level 1 trauma centers in a single city, limiting generalizability. And, Conner and colleagues added, the possibility that Houston’s lower population density, reduced public transit options, and significantly higher use of personal motor vehicles for transportation relative to other cities led to higher rates of impaired driving, “in that people are more likely to imbibe further from home and with fewer options to travel.”

  1. The introduction of rideshare services to the Houston area led to a significant decline in rates of trauma related to motor vehicle crashes (MVCs), along with fewer convictions for driving under the influence (DUIs), according to results from a multicenter cohort study in Houston, Texas.

  2. Increased use of rideshares may be an effective means of reducing impaired driving and decreasing [the] rate of MVC traumas, though further research is needed focus on the association between demographics and socioeconomic status and ridesharing services, MVC traumas, and impaired driving in other metropolitan areas beyond Houston.

John McKenna, Associate Editor, BreakingMED™

The study authors had no relevant relationships to disclose.

Haider and Shahbaz had no relevant relationships to disclose.

Cat ID: 254

Topic ID: 253,254,254,730,192,151,925