Prevalence of benign paroxysmal positional vertigo in a population-based setting among 75-year-olds

1 Introduction

Many older adults experience dizziness and imbalance, which are major contributors to falls and seeking medical care. At older ages, gradual multisensory deterioration of balance commonly occurs since there is a natural decline in the vestibular system as well as the proprioception and central pathways. Benign paroxysmal positional vertigo (BPPV) is a common cause of dizziness that is more common among older adults and women [11, 13]. The cumulative lifetime incidence of BPPV is around 10% [35], but the reported prevalence of BPPV in geriatric settings is as high as 9% [14, 25].

General symptoms of BPPV are dizziness or vertigo after positional changes, like lying down or turning in bed, or turning the head backwards, lasting less than one minute, [7, 33]. But a sensation of unsteadiness and imbalance may occur as well. Older adults with BPPV may experience rotatory dizziness symptoms less often and non-specific unsteadiness more often than younger people [29]. The diagnosis of BPPV is typically made using the Dix-Hallpike test for posterior canal BPPV (pBPPV) and a supine roll test for horizontal canal BPPV (hBPPV) [33]. Using Video Frenzel goggles allows the eyes of the patients to be visualized on a screen, making it easier to detect nystagmus. Positional vertigo lasting less than one minute together with positional nystagmus, coming on with a few seconds of latency, is indicative of the condition [33]. Positional symptoms of dizziness without nystagmus indicate subjective or probable BPPV, which is not uncommon [1].

The prevalence of BPPV increases with age [11, 13], and the condition has been diagnosed more frequently and became more in focus in recent years [13, 26]. This could be due to increased knowledge about the disorder and the increased use of Video Frenzel goggles, leading to better detection. Once BPPV has been diagnosed, initiation of treatment is highly recommended [4, 30]. Treatment of BPPV entails getting the otoconia back to the utricle by using repositioning maneuvers, like Epley’s or Semont’s maneuver for pBPPV. However, treatment can be more challenging in older adults compared to those who are younger and may require several repositioning maneuvers for complete recovery [1]. Moreover, the risk of relapse of BPPV is believed to be as high as around 50% [28, 32]. Older age, female sex, Meniere’s disease, osteoporosis, and vitamin D deficiency are factors that seem to enhance the risk of recurrence [32]. Living with prolonged dizziness is associated with reduced health-related quality of life [21], even after adjusting for different diseases [22]. The sensation of severe dizziness or vertigo is unpleasant and may easily cause anxiety, fear, discomfort, and loss of feeling of control, leading to avoidance of movements that trigger dizziness.

Positional nystagmus, is nystagmus triggered by, and occurring after, a change in head position in respect to gravity [15]. Positional nystagmus can be due to variants of BPPV, or by changes in cerebellum or pons, referred to as central positional nystagmus (CPN) [15] Asymptomatic positional nystagmus of low intensity may as well be seen in asymptomatic individuals [12, 24]. Central positional nystagmus is often suspected when BPPV can be ruled out and is believed to be caused by cerebellar or brainstem dysfunction or degeneration [15]. It can be both paroxysmal as well as persistent and is believed to be found in around 12% of all cases of positional nystagmus [3]. Positional nystagmus, without dizziness, can also be due to compensated BPPV, vestibular migraine [37] or other excitement in the brainstem or cerebellum [5].

At this time, the prevalence of BPPV on a population level remains unclear and there are reports showing that BPPV can remain undiagnosed, especially among older adults [18, 25]. Few population-based studies have been conducted and, to our knowledge, no previous population-based study has used Video Frenzel goggles for BPPV testing. The aim of this study was to investigate the prevalence of BPPV and positional symptoms of dizziness and nystagmus among a large population of 75-year-olds in the population in Gothenburg, Sweden, who underwent the Dix-Hallpike test using video Frenzel goggle.

2 Method

The study is based on the Gothenburg H70 Birth Cohort Studies (The H70 studies), which is a multidisciplinary epidemiological study examining birth cohorts of older populations in Gothenburg, Sweden. The study aims to examine health and health-related factors in a representative sample of the population and is performed at the Neuropsychiatric Clinic at Sahlgrenska University Hospital or though home visits. Study participants born on pre-specified birth dates ending with 0, 2, 5, 8 and registered as residing in ordinary or special housing in Gothenburg, Sweden, were invited to participate. Information regarding date of birth and address was obtained from the Swedish Population Register, covering all persons registered in Sweden. Invitations to participate in the study were first sent by letter, including the consent form, and then all invited participants were contacted by telephone. A full description of the inclusion criteria and methods has been published elsewhere [30]. In the current study, the participants were born in 1944 and examined at ages 75–78. The aim was to examine all participants at age 75, but due to the COVID-19 pandemic, the examinations were stopped for a period, and the examination time was prolonged A total of 1460 all aged 75–78, were eligible for invitation to the multidisciplinary study and a total of 902 participated (response rate 61.8%).

3 Result

A total of 902 individuals were investigated. Of the 902 individuals, 59 had a home visit and were therefore excluded from investigation with Dix Hallpike/side lying test, as this was only performed at the outpatient clinic, leaving 843 individuals. Of these, 700 (83%) underwent BPPV testing. Among those performing a BPPV test, 18 did not have complete test data and 1 had missing data on the dizziness question and were therefore excluded, leaving 681 participants (hereafter referred to as the BPPV test sample). In the BPPV test sample, 668 performed the Dix-Hallpike test and 13 performed the side-lying test. A total of 887 (98%) answered the questions regarding dizziness and, 282 (32%) reported problems with dizziness. There was a sex difference in the prevalence of dizziness, where 39% (n = 182) of the women and 24% (n = 100) of the men reported problems with dizziness (p < 0.001). Problems with dizziness when turning in bed were reported by 87 (9.8%).

There were several differences between those included in the BPPV test sample (n = 681) and those who were excluded (n = 221). Excluded participants were more frequently women, had a lower educational level, and were more likely to live alone and less likely to have a partner. Moreover, these individuals had higher BMI, and were more likely to have back pain, gait impairment, joint problems, heart failure, and anxiety, and reported worse self-rated health, and took more medications. In addition, excluded participants reported longer durations of dizziness and unsteadiness as well as dizziness during positional changes when lying down, turning in bed, or turning the head backward. In addition, they experienced a spinning, rotational sensation of dizziness more frequently, reported greater obstacles in daily activities due to dizziness, and sought medical care for dizziness more often, see Table 1. A total of 73 excluded participants reported a reason for not undergoing testing for BPPV; the most common reason was fear of becoming dizzy during the test (n = 39), followed by back pain (n = 18), see Table 2.

In this study investigating the occurrence of BPPV and positional symptoms of dizziness and nystagmus in a population-based setting, we found a prevalence of BPPV of 4% (4.5% in the weighted sample) among 75-year-olds who underwent testing. Across published literature, the occurrence and prevalence of BPPV differ greatly depending on the study method, setting, and age of the participants, ranging from 1–2% [11, 35], up to 10% [8, 25]. In general, BPPV is more frequent and more persistent among older adults.

Positional dizziness, but no nystagmus was seen among 2% in the cohort, and positional nystagmus, but no dizziness was seen among 8.8%. In addition, participants diagnosed with BPPV and those who experienced positional dizziness during the BPPV test, reported more problems with dizziness in their daily lives compared to those with normal test results, while those with positional nystagmus did not. Peripheral vestibular stimulation and reflexes decline with age, and may affect balance and contribute to falls [16]. Peripheral nystagmus may be seen even without a sensation of dizziness among older adults, still increasing fall risk [10], however, the participant in this study did not reported enhanced level of dizziness or unsteadiness. A reason for this might be that we have targeted healthy individuals with positional nystagmus.

The prevalence of BPPV in the current study cohort is lower than the 10% we previously reported in a cohort at the same age [14, 21]. However, in this current study, Video Frenzel goggles were used, and nystagmus together with dizziness were set as the requirement for the diagnosis of BPPV according to the Barany Society criteria. In contrast, the prior cohort was tested without Video Frenzel goggles, and visible nystagmus was not set as a criterion [34]. Another important reason is the enhanced knowledge about the condition that has been reached in the resent years, and more patients seeking care for dizziness being diagnosed and get treatment for their BPPV, thereby lowering the prevalence of the condition on a population-based level.

In total, about a quarter of participants did not undergo testing for BPPV. This group reported more balance problems, had more issues with dizziness, more anxiety, and had more health problems than the group who underwent testing. In addition, this group reported more frequent symptoms of positional dizziness, such as dizziness when lying down, turning in bed, or turning the head backward. As these symptoms are typical of BPPV, some participants who declined testing likely had undiagnosed BPPV. To compensate for this, we performed weighted analyses based on sex and the question regarding positional dizziness when lying down or turning in bed, which increased the prevalence of BPPV from 4.0% to 4.5%. However, the weighted analyses may not have fully compensated for the selective attrition, and the true prevalence of BPPV could be higher.

The most common reason provided by participants for not undergoing BPPV testing was fear of becoming dizzy during testing. This finding illustrates the degree of discomfort, fear, and inconvenience associated with dizziness among older adults and the subsequent impacts on quality of life, which have been documented by others [19, 21]. In our cohort, the participants diagnosed with BPPV reported more problems with dizziness and experienced more positional symptoms of dizziness in everyday life than those with normal test results, which is in line with previous studies [20]. While BPPV is common in the community and has received more focus in the last few years, the level of knowledge about the condition may vary among healthcare professionals. Since older adults may present with milder, more unspecific symptoms [2, 29], and have complications due to reduced mobility and stiffness of the neck [1], positional testing for BPPV may not be implemented. Moreover, BPPV may be more difficult to treat in older adults and require several treatment maneuvers. A plausible reason for treatment difficulties is the semicircular canal being plugged (canalith jam) with otoconia [31], as well as the more uneven surface of the semicircular canals where otoconia may attach. These factors could reduce the tendency to test for BPPV in the community, along with the initiation of appropriatetreatment.

Another important finding of the study was that 8.8% of the participants had positional nystagmus without dizziness during BPPV testing. These participants did not differ from those with normal test results regarding self-reported symptoms of dizziness or other factors, such as self-rated health, heart diseases, or symptoms of anxiety (Table 4). Positional nystagmus may occur among asymptomatic, healthy individuals [24] and can be a symptom that is often seen along with vestibular migraine [37]. The frequency of positional nystagmus among older adults in the population has, to our knowledge, not been previously explored. The mechanism of positional nystagmus in healthy individuals has yet to be elucidated and further research is necessary and encouraged. A possible explanation could be that older adults have less vestibular perception not recognizing the stimuli caused by BPPV. If so, these patients could constitute a subgroup with ‘subliminal’ BPPV. Such patients could be expected to have reduced balance control with an increased risk of falls due to undiagnosedBPPV.

Dizziness accounts for about 2% of all medical visits in both primary care and emergency settings [9, 23]. In many of these visits, no diagnosis is made [26]. BPPV is not only a treatable cause of dizziness, but a condition where a definite diagnosis can be made, with simple testing not requiring advanced technology. Severe symptoms of BPPV such as vertigo, vegetative symptoms like nausea, vomiting, and discomfort usually decline within a few days after an acute episode, even without treatment. However, milder symptoms of impaired equilibrium can persist, causing distress over a longer period of time. Receiving the correct diagnosis and treatment for BPPV early on, may not only cure or diminish symptoms but also restore a feeling of control and reduce the fear that dizziness may trigger. Treatment may also reduce avoidance of activities and head movements, and lower the risk of imbalance, falling, and the development of functional dizziness like persistent positional perceptual dizziness (PPPD). Enhancing knowledge about BPPV, including its diagnosis and treatment, should be a priority among physicians treating older adults in a community setting.

5 Conclusion

The prevalence of BPPV was estimated at 4.5% in a cohort of 75-year-olds who underwent testing. Despite the weighted analyses, the true prevalence of BPPV may be higher since many participants with dizziness symptoms refused testing, commonly due to fear of experiencing dizziness and a strong sense of discomfort. Positional nystagmus without dizziness was present in 8.8% of participants. Further research is needed to elucidate the mechanisms behind positional nystagmus in otherwise healthy individuals. Prioritizing testing for BPPV can help find and treat older adults for dizziness.