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Knowledge of Risk Factors for Falling Reported by Patients with Parkinson Disease

Sadowski, Cheryl A.; Jones, Allyson C.; Gordon, Beverly; Feeny, David H.

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Author Information

Questions or comments about this article may be directed to C. Allyson Jones, PhD, at cajones@ualberta.ca. She is an assistant professor in the Department of Physical Therapy at the University of Alberta, Edmonton, Alberta, Canada.

Cheryl A. Sadowski, PharmD, is an associate professor on the faculty of Pharmacy and Pharmaceutical Sciences at the University of Alberta, Edmonton, Alberta, Canada.

Beverly Gordon, BSc (Pharm), was an undergraduate student within the faculty of Pharmacy and Pharmaceutical Sciences at the University of Alberta, Edmonton, Alberta, Canada, at the time of this study. She is currently employed as a pharmacist.

David H. Feeny, PhD, is a senior investigator and assistant program director in the Science Programs Department at the Kaiser Permanente Northwest Center for Health Research, Portland, OR.

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Abstract

This study examined awareness of the risk factors for falling among a group of community dwelling patients with Parkinson disease (PD) using the Falls Risk Awareness Questionnaire (FRAQ). A cross‐sectional survey of 28 patients who attended a Movement Disorders Clinic for treatment of PD was used. FRAQ is a 28‐item self‐administered survey that assesses the knowledge and perception of risk factors for falling. Demographic, medical, and medication data were gathered from both the participants and clinic charts. Twenty‐three (82%) of the participants reported falls in the past; seven (30%) had fallen within the past month. Nineteen (68%) of the participants felt they were at risk for further falls. When asked to list potential risk factors for falling, only 14% could identify medication as a risk factor. Persons with PD are at substantial risk of falling, yet many appear to be unaware of common risk factors, especially medication use.

Falls in the elderly population constitute a significant risk for injury and death (Ashburn, Stack, Pickering, & Ward, 2001b; King & Tinetti, 1995). In turn, falls increase short‐ and long‐term use of healthcare resources (Pressley et al., 2003; Rizzo, Baker, McAvay, & Tinetti, 1996; Wilkins, 1999). Although falls in Parkinson disease (PD) have not been extensively examined, falling is the most common complication of PD, with reported rates from 51% to 68% (Ashburn, Stack, Pickering, & Ward, 2001a; Bloem, Grimbergen, Cramer, Willemsen, & Zwinderman, 2001; Gray & Hildebrand, 2000; Wood, Bilclough, Bowron, & Walker, 2002). Koller, Glatt, Vetere‐Overfield, and Hassanein (1989) found that 13% of patients with PD fell more than once a week. Gait impairment and postural instability greatly increase the risk of falls in this patient population (Ashburn et al., 2001a; King & Tinetti, 1995; Wood et al., 2002). Perhaps more noteworthy, polypharmacy and impaired mood are two additional risk factors strongly associated with falls in persons with PD (Ashburn et al., 2001a).

Falls by patients with PD can have devastating effects on their ability to live independently and can often lead to admission to a hospital or nursing home (Wood et al., 2002). Because persons with PD are twice as likely to fall as the general population or matched controls (Genever, Downes, & Medcalf, 2005; Teno, Kiel, & Mor, 1990), routine fall assessment in the clinical context is potentially valuable in this patient population.

An integral component of primary prevention of falls in this high‐risk group is an evaluation of patient and caregiver awareness of the risk factors for falls. Patients and caregivers may not be aware of the increased risk for falls or predisposing factors (Gray & Hildebrand, 2000). Deficits in the knowledge of specific risk factors can be targeted as a preventive strategy for avoiding falls. Although recent studies have attempted to document the risks for falling in the general elderly population, and to a certain degree in the PD patient population, no investigations (to our knowledge) have examined patient awareness of the risks for falling in this high‐risk group.

The objective of this study was twofold: (1) to examine the knowledge of the risk factors for falling within a group of community‐dwelling participants with PD using the Falls Risk Awareness Questionnaire (FRAQ) and (2) to examine the associations between participant characteristics and awareness of the risk factors for falling.

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Methods

The study was a cross‐sectional survey of a consecutive sample of outpatients with PD who attended the Movement Disorders Clinic at the Glenrose Rehabilitation Hospital in Edmonton, Alberta, Canada, between January 29 and March 18, 2003. The Movement Disorders Clinic consists of three neurologists and allied health professionals. The clinic serves northern Alberta with a catchment area of approximately 1.5 million people. Patients attend the clinic on a biannual basis and represent a range of ages and disease severity.

Inclusion criteria for the current study were a diagnosis of PD and English literacy. All patients who were invited to participate agreed to complete the survey. Approval was obtained from the ethics committees of the university and health region.

The self‐administered survey was given to participants when they attended the clinic. A research assistant provided a brief introduction to the project. If the participant was unable to complete the questionnaire independently, the research assistant helped with reading or writing. A clinic chart review was also completed using a standardized review form. Demographic data including date of birth, gender, marital status, and place of residence; medical data including history of falls, ambulatory status, comorbidities, date of diagnosis, and Unified Parkinson's Disease Rating Scale (UPDRS); and medications currently prescribed were collected from the clinic records.

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Measures

The UPDRS (Fahn, Elton, & UPDRS Developmental Committee, 1987) for motor impairment was recorded from the chart to measure disease severity. The number and type of comorbid conditions were identified using a list of 16 comorbid conditions. Comorbid conditions reported by both the patient and within the clinic chart were combined to provide an overall list of chronic conditions. A listing of general categories for medications derived from the Statistics Canada National Population Health Survey (NPHS; Statistics Canada, 2004) was used in both the survey and the chart review.

The FRAQ was developed by Wiens, Koleba, Jones, and Feeny (2006) to assess the knowledge and perception of risk factors for falling. Evidence on the acceptability and construct validity of the FRAQ has been presented (Wiens et al.). Revisions required for the current study involved the inclusion of questions about movement problems specific to PD and medications for PD.

The FRAQ comprises four parts. The first section of the questionnaire, administered by the interviewer, contains three open‐ended questions concerning identification of risk factors for falling and sources of information about fall risks. The second and third sections were completed by the respondent. The second section consisted of 28 multiple‐choice questions about the risk factors of falling. The risk factors are evidence‐based and were identified by a literature search of the Medline, CINAHL, and Ageline databases. “Distracter” items such as specific medications or activities that were deemed not to be risk factors were also included to avoid spurious positive responses to listing only known risk factors. Items were listed in lay language, and examples were given when appropriate. For example, two common product brand names of sedative‐hypnotics were listed beside “sleeping pills.”

Established risk factors for falls included in the FRAQ consisted of impaired neuromuscular function, muscle weakness, impaired balance, vestibular pathophysiology, impaired proprioception, abnormalities of the feet, dementia and impaired cognition, acute illness, advanced age, female gender, stroke, and fear of falling (Cumming, 1998; Grisso et al., 1991; O'Loughlin, Robitaille, Boivin, & Suissa, 1993; Tinetti et al., 1994; Tinetti, Speechley, & Ginter, 1988; Tinetti & Williams, 1998). Medication items included use of multiple medications, psychotropic drugs such as antidepressants, antipsychotics, anxiolytics, and hypnotics (Cumming, 1998; Cummings & Nevitt, 1994; Leipzig, Cumming, & Tinetti, 1999a; Liu et al., 1998; Ray, Griffin, Schaffner, Baugh, & Melton, 1987; Thapa, Gideon, Cost, Milam, & Ray, 1998; Tinetti et al., 1994; Tinetti, Inouye, Gill, & Doucette, 1995). Fear of falling, improper use of ambulation aids, activities that displace one's center of gravity, and inappropriate footwear were also included in the survey (Cumming, Salkeld, Thomas, & Szonyi, 2000; Grisso et al., 1991; Murphy, Dubin, & Gill, 2003; Murphy, Williams, & Gill, 2002; Tinetti et al., 1994).

The third section includes 13 questions on demographic (age, sex, marital status, education) and medical (disease duration, duration of symptoms, comorbid conditions, medications, ambulatory status) factors. The fourth section was intended to gain feedback about the survey. It includes seven openended questions, administered by the interviewer, about the comprehension and content suitability of questions in sections 1 through 3 and solicited suggestions to improve the comprehension of the survey. The purpose of these feedback questions was to provide an unstructured process for participants to assist in further refinement of the instrument.

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Analysis

Descriptive statistics were used for all variables collected. To assess the significance of associations among categorical variables, chi‐square tests were performed. Independent sample t tests were used for normally distributed continuous variables. The relationships among participant characteristics, such as demographic information, comorbid conditions, health status, and perception of risk factors, were examined. The number of comorbid conditions was categorized into three groupings (1‐2, 3‐4, greater than 4 conditions). Disease duration was categorized into two groups (≤5 years, >5 years). A multiple logistic regression was used to obtain the odds ratios for factors, which may explain the rate of self‐reported falling in the past year. To adjust the model, the number of comorbid conditions was forced into the final parsimonious model. Model goodness‐of‐fit was evaluated using the Hosmer‐ Lemeshow test statistic (Hosmer & Lemeshow, 1989).

Although our cohort recognized that their probability of falling was substantial, they lacked awareness of specific risk factors for falling, particularly those associated with medication use.

All statistical testing was performed with twotailed tests and at a .05 level of significance unless otherwise stated. Statistical analyses were performed using the SPSS® software version 12.0.1 for Windows, SPSS Inc.

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Results

Our sample consisted of a consecutive series of 28 participants. All of those who were eligible to participate completed the survey; 17 (61%) were able to complete the survey independently. Participant characteristics are shown in Table 1. The mean age was 61 years (SD = 10.8); 15 participants (54%) were female; and the majority of participants (n = 26) had at least a high school education. No participants resided in institutions or long‐term care facilities. Twenty‐three (82%) participants rated their health as good or very good. The mean number of comorbid conditions was 3.1 (SD = 1.7). Bladder problems, arthritis, and lower back pain were the three most commonly reported conditions.

Table 1
Table 1
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Fifteen participants (54%) had been diagnosed more than 5 years before the survey; 7 participants (25%) had reported movement problems for longer than 5 years. The mean score for the UPDRS3 (motor component) for participants who were on their medications was 20 (SD = 13.2), indicating mild to moderate involvement. Twenty‐two participants (79%) stated they could ambulate independently; 14 (63%) of these were able to walk six or more blocks. Participants typically were prescribed one medication (range 0 to 3) for PD. The most common medication was a levodopa‐carbidopa product (n = 21).

Twenty‐three participants (82%) stated they had fallen in the past; 7 (30%) had fallen within the past month, and another 14 (61%) had fallen within the past year. Nineteen participants (68%) felt they were at risk for further falls because of their age or sex. No statistical differences were seen among participants who reported falls within the past 6 months, those who had fallen in the past year, and those who had not fallen (p > .05). Controlling for the number of comorbid conditions, disease duration (odds ratio [OR] 3.26: 95% confidence interval [CI], 0.47‐22.78) and UPDRS3 (OR 1.01: 95% CI, 0.94‐1.09) were not statistically significant in explaining a past history of falling.

Many of the participants knew that older people are at risk of falling (n = 26 [93%]); many felt they were personally at risk for falling (n = 19 [68%]). Using an open‐ended question format in the first section of the survey, 22 participants (78%) were able to identify between 1 and 4 causes for falls. The most frequently identified causes for falls were physically related. The most infrequently identified causes for falls were medication related (n = 4 [14%]). Many of the participants (n = 26 [93%]) acknowledged that risky behaviors could be changed to prevent falls. Most participants received information about risk factors for falls from friends or family (n = 17 [61%]); only a small proportion reported obtaining information from health professionals (n = 5 [18%]) or the media (n = 4 [14%]).

There were 14 participants (64%) who felt that taking more medications would increase the chance of falling, yet only 4 participants (14%) could identify any specific medications that could contribute to falling. When presented with a list of 15 medications as potential risk factors for falling, participants were able to identify correctly 3.2 (SD = 2.8) medications as risk factors. Narcotics (n = 15 [53%]), neuroleptics (n = 12 [43%]), and antihypertensive agents (n = 11 [39%]) were the three most common medications identified as risk factors for falling. Diuretics (n = 2 [7%]) and nonsteroidal antiinflammatory medications were less likely to be cited as risk factors. The number of medications taken, however, was only negligibly correlated with the number of medications identified as risk factors (r = .09). Patients who took many medications did not necessarily have more knowledge of the adverse effects of medications relating to falls.

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Discussion

This is the first study to our knowledge to examine participant knowledge and perception of risk factors for falling for patients with PD. Three‐quarters of our community‐based sample reported falling within the past year. This proportion is slightly higher than the proportion reported by Ashburn and colleagues (2001a).

Interestingly, we did not find an association between disease duration or severity and falling when controlling for the number of comorbid conditions. Other researchers have reported a relationship between disease severity and falls using univariate analysis (Ashburn et al., 2001a; Wood et al., 2002). This relationship may not have been evident in our study group for a few reasons. First, the characteristics of our study group may be different from other cohorts—only 28 participants were involved, and all were living in the community. Second, differences may have existed in terms of recall bias for recounting falling and the categorization of data such as disease duration.

This study group was distinct from healthy elderly persons in the community because they recognized their susceptibility to falling. This finding differs from reports of healthy community‐dwelling elderly persons; elderly participants recognize that falls are common in older age, yet personally they do not feel at risk for falling (Braun, 1998; Wiens et al., 2006).

Falls in the PD population are fairly common given the progression of the disease and the inherent risks of falling associated with PD—postural instability, rigidity, and bradykinesia. Taking into consideration the side effects of many PD medications such as dyskinesias, hypotension, confusion, and hallucinations, persons with PD are at considerable risk for falling. This was exemplified by the frequency of falling recorded by many of the participants and their awareness of the risks of falling. Although the majority of participants felt that behavior could be changed to reduce the chances of falling, the survey did not address whether the participants took extra precautions to modify their own behavior to avoid falls.

Although our cohort recognized that their probability of falling was substantial, they lacked awareness of specific risk factors for falling, particularly those associated with medication use. This was a surprising finding, considering that the participants enrolled in this study were taking numerous medications, and many of those medications are known to increase risk for falling. The fact that these individuals attended a movement disorder clinic led us to hypothesize that their awareness of all risk factors would have been much higher. Specific medication classes, such as barbiturates (Grisso et al., 1991), selective serotonin reuptake inhibitors (Liu et al., 1998; Thapa et al., 1998), tricyclic antidepressants, benzodiazepines, neuroleptics and sedative hypnotics (Cumming, 1998; Cummings & Nevitt, 1994; Leipzig et al., 1999a; Ray et al., 1987), digoxin, type 1A antiarrhythmics and diuretics (Leipzig, Cumming, & Tinetti, 1999b), hypoglycemics (Fuller, 2000), and alcohol are regarded as medications that may increase the risk of falling.

Medications that contribute to falls, including antidepressants or benzodiazepines, may be frequently used in patients with PD. Approximately 20% of patients with PD have a diagnosis of depression, 40% have anxiety or panic, and up to 90% have sleep complaints (Lauterbach, 2004). It is particularly disconcerting that these individuals were not more aware of psychotropic medications as risk factors for falling.

It is also of clinical relevance that only a small proportion listed health professionals as a source of information for the risk factors of falling. The main source of information reported was friends or family. Persons with PD represent a high‐risk group for falling and have frequent contact with the healthcare system, yet are unaware of most of the risk factors associated with falling. An earlier survey found that healthcare professionals (physicians, pharmacists, registered nurses, licensed practical nurses, physical and occupational therapists, social workers, and dietitians) were aware of risk factors for falling (Wiens et al., 2006). One strategy for fall prevention may be for health professionals to assess patients' knowledge of the risk factors for falling routinely and then provide education in deficit areas.

The findings of this survey should be interpreted with caution for several reasons. First, the external validity is limited, because this was a cross‐sectional survey of a convenience sample. The cohort was not necessarily representative of this patient population because participants were solicited from a specialized clinic over a brief period of time. Second, it may not be reasonable to expect patients to be aware of specific medications as risk factors if they are not taking those medications. Third, although there is evidence of the construct validity of the FRAQ, further evidence of its measurement properties is still needed. Fourth, the sample size is small, and thus the power to detect associations between awareness and other factors is limited.

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Summary

Although the participants may have been reasonably aware of the risks for falling, they were still falling frequently. The findings from this study suggest that a primary preventive program directed at more disease‐specific awareness and education may be helpful in reducing the frequency and injuries due to falls in this patient population. Patients with PD may be taking a number of medications for conditions other than PD, which may also increase the risk for falling. It is possible that asking about falls should be a component of standard care for patients with PD. In particular, a formalized education program about non‐Parkinson medications that elevate the risk for falling may be of value in patients with PD. Further investigations, such as defining the prevalence of falling in this patient population as compared to the general population and examining the efficacy and effectiveness of an education program to prevent falling, are needed to determine the risk factors for falling in the PD patient population and how to reduce the frequency and severity of falls.

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Acknowledgments

We would like to thank the staff at the Movement Disorders Clinic, in particular, Marguerite Wieler, MSc BA BSc(PT), and Richard Camicoli, MD FRCP(C), for their support of this study.

This research project was supported by a grant from the Institute of Health Economics (IHE). This funding agency played no role in the design, interpretation, or analysis of the project reported here and has not reviewed or approved this manuscript.

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