Link Between Number of Falls With Annual Incidence of Having At Least One Fall

^{By Renee Campbell, MD, MBA, MPH, Global Value and Access Epilepsy and Sleep lead, Genevieve De Sousa Meier, Executive Director, Head of Global Value and Access, and Amir Abbas Tahami Monfared, executive director, Franchise Head of Global Value, Access, Pricing and HEOR, all from Eisai} 

Insomnia is the most common sleep-wake disorder, affecting approximately 20% of adults age 65 and older in the US and its prevalence increases with age.¹ Poor sleep, and the use of some types of medications to treat it, is associated with increased risk of falls, which are the leading cause of fatal and nonfatal injuries among older adults.²  

More than one in four people age 65 and older fall each year; moreover, falling once doubles the chances of a recurring fall.³ In the US, the number of falls and the significant medical costs associated with them are expected to increase with the aging population.⁴

Our recent study⁵ was designed to understand the impact of falls by quantifying the relationship between the annual incidence of having at least one fall and the mean annual number of falls per faller. 

The Medicare Current Beneficiaries Survey (MCBS) is a longitudinal representative survey of the US Medicare population conducted annually by the Centers for Medicare and Medicaid Services. The 2016 MCBS data set includes 12,852 community-dwelling respondents age 65 or older interviewed in 2016.

Respondents were asked how many falls they had had in the last year, how many chronic conditions they had and to rate their general health. The annual incidence of having at least one fall and the mean annual number of recurrent falls per faller were then estimated. The relationship between the incidence of first falls and the number of falls per faller also was compared for those reporting chronic conditions and those reporting general health for which the incidence of first falls differed.  

Older adults who had a fall were twice as likely to have another fall in the same year

In this study, the annual incidence of at least one fall was 0.237 (95% CI: 0.23, 0.25) in 2016. Those who reported at least one fall were twice as likely to have another fall in the same year: the proportion with a subsequent fall in the same year was 0.50 (95%CI: 0.48, 0.53).   

Among those who reported at least one fall, the mean number of falls per faller in one year was 1.96 (95% CI: 1.90, 2.02). 

Older adults with more chronic conditions or with worse self-reported health had a higher proportion of annual falls and more subsequent falls per person

Across the categories of chronic conditions and self-reported health, the annual incidence of having at least one fall varied from 0.1 for those reporting excellent health to 0.5 for those reporting poor health. The mean number of falls per person who reported at least one fall varied from 1.5 for those reporting excellent health to 2.5 for those reporting poor health. 

Among older adults with more chronic conditions or with worse self-reported health, a higher proportion of first falls correlated with a higher number of subsequent falls

This data reflects patient groups with a higher proportion of first fallers also have a higher mean number of falls per faller. Specifically, in this data analysis, across patient groups, a 0.1 higher incidence of first falls was associated with an estimated 0.25 (95% CI: 0.20, 0.30) more falls per person.  

Given insomnia is common among older adults and the condition, as well as some medications used to treat it, are known to increase the risk for falls, these findings suggest clinicians should consider assessing patients for insomnia and screening for falls when determining an appropriate insomnia treatment.  

The following limitations were noted by the study authors.

The estimates from the 2016 MCBS are for people age 65 years or older in the US community-dwelling Medicare population and are not necessarily generalizable to other patient populations. In addition, the 2016 MCBS is based on self-reporting, which may be affected by recall bias as respondents have to remember how many falls that they had in the year before interview. Although the analysis showed an approximately linear relationship between the incidence of first falls and the number of falls per faller for the patient groups in this analysis, it is possible that the relationship is different for other patient groups, eg, defined using criteria other than self-perceived health or chronic conditions, or in other countries or age groups. Finally, this analysis does not establish that the relationship is causative.

References:

1. Roth T. Insomnia: definition, prevalence, etiology and consequences. J Clin Sleep Med. 2007;3(5 Suppl):S7–S10.
2. Nguyen KL, Watanabe JH. Association Between Sleep Medications and Falls and Fall-related Worries in Community-Dwelling Older Adults in the United States. Journal of Contemporary Pharmacy Practice. 2019;66(3):23–32.
3. Centers for Disease Control and Prevention (CDC). Older Adult Fall Prevention: Facts about Falls. Available at https://www.cdc.gov/falls/facts.html. Accessed December 2020.
4. Florence CS et al. The Medical Costs of Fatal Falls and Fall Injuries among Older Adults. J Am Geriatr Soc. 2018;66(4):693–698.
5. Adena M, O’Leary B, Monfared AAT, et al. The Number of Falls Per Faller Varies With the Annual Incidence of Having At Least One Fall. Presented at AMCP Nexus 2020. October 20-23, 2020.