Benign Positional Paroxysmal Vertigo or BPPV is condition caused by a disruption of the vestibular system which is found in the inner ear. Within this system is a collection of calcium crystals known as otoconia which play an important role in signalling to the brain where the head is in space. In BPPV these crystals can become dislodged and move into the canals, which can disrupt the signals being sent to the brain. In result changes in head position such as rolling in bed can cause symptoms including dizziness or the sensation that the room is spinning.
Anyone who has had BPPV may notice that it seems to only affect them certain times of the year or only come on with changes in the weather. Well if so, you are not alone. Recent research has explored whether a relationship exists between the occurrence of BPPV and different climate conditions such as temperature, sun radiation, and air pressure. The results of three large retrospective studies all found that there is a negative correlation between BPPV and temperature, meaning when the temperature increases, the number of cases of BPPV decrease (Korpon, Sabo, and Coelho, 2019; Mariani, Pelagatti, Hahn, and Alpini, 2008; and Saeed and Omari, 2016). This relationship was also found for the climate variables sun radiation, UV index, and hours of sunlight. Research also indicates that there is a positive correlation between atmospheric pressure and BPPV, as the incidence of BPPV increased with each unit rise of pressure (Korpon, Sabo, and Coelho, 2019). While research clearly demonstrates a relationship between different weather conditions and BPPV; the direct reason is still unknown. However, various theories have been put forward to try to explain these relationships.
One theory to describe the increased incidence of BPPV in colder weather is due to the role of vitamin D on osteoporosis. There is a greater prevalence of BPPV in women, which has previously been researched and connected to the prevalence of osteopenia and osteoporosis (Vibert, Kompis, and Häusler, 2003). Thus, the authors of the retrospective study infer that the higher incidence of BPPV in the winter months can be in part explained by the shorter daytime and lower exposure to sunlight which may result in vitamin D deficiency and subsequent bone demineralization (Saeed and Omari, 2016). Other theories propose that the increased cases of BPPV during certain months may be related to nasal allergies, or sinus disease and respiratory tract infections (Cohen et al., 2010). Another theory is that temperate and pressure can affect the metabolism of the inner ear by increasing the amount of systemic oxidative stress (Korpon, Sabo, and Coelho, 2019).
In conclusion, there is recent research indicating a correlation between BPPV and differing climate conditions. However, the direct ways in which the climate conditions affect BPPV is still unclear and further research is required.
References
Cohen, H. S., Stewart, M. G., Brissett, A. E., Olson, K. L., Takashima, M., & Sangi-Haghpeykar, H. (2010). Frequency of sinus disease in normal subjects and patients with benign paroxysmal positional vertigo. ORL; journal for oto-rhino-laryngology and its related specialties, 72(1), 63
Kaplan, D. M., Nash, M., Niv, A., & Kraus, M. (2005). Management of bilateral benign paroxysmal positional vertigo. Otolaryngology-Head and Neck Surgery, 133(5), 769-773.
Korpon, J., Sabo, R., & Coelho, D. H. (2019). Barometric pressure and the incidence of benign paroxysmal positional vertigo. American Journal of Otolaryngology.
Mariani, P., Pelagatti, M., Hahn, A., & Alpini, D. (2008). Epidemiology of paroxysmal positioning vertigo: correlation with seasons, climate, and pollution. Int Tinnitus J, 14(2), 168-174.
By Hannah Angermann Student Physiotherapist
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