Sleep bruxism reflects masticatory muscle behavior tied to health deterioration not mortality

The association of sleep bruxism with mortality has not been studied previously.

This is the first study to examine the relationship between sleep bruxism and mortality. The association between sleep bruxism and increased risk of mortality did not hold when the regression model was adjusted for known risk factors for mortality. Sleep bruxism is not a disease that kills but rather reflects a masticatory muscle behavior detrimental to health.

Altogether 12 040 subjects from the nationwide Finnish twin cohort were included in the analyses. We examined whether self-reported sleep bruxism is associated with increased risk of mortality, and if so, whether the effect is independent of known common risk factors. The time span of the follow-up was 30 years.

Cox proportional hazards regression models (Hazard Ratios and their 95% Confidence Intervals) adjusted by age, sex and covariates were used to assess the effect of baseline bruxism status in 1990 on future mortality in 1990–2020.

Results

The risk of mortality among all participants (n = 12 040), independent of missing covariates and adjusted by age and sex, was 40% higher in weekly bruxers than in never bruxers However, when adjusted by all studied covariates, (n = 11 427) the risk was no longer observed

Despite the overall lack of between bruxism and mortality after adjustment for covariates, we examined the cause-specific risks for major cause-of-death groups.

There were no substantial associations of weekly bruxism with major disease outcomes by the fully adjusted hazard ratios for them.

Bruxism does not kill—in line with its definition of being rather a behaviour (with all its phenotypes) than a disease.

Reference:

Ahlberg, J, Lobbezoo, F, Manfredini, D, Piirtola, M, Hublin, C, Kaprio, J. Self-reported sleep bruxism and mortality in 1990–2020 in a nationwide twin cohort. J Oral Rehabil. 2023; 00: 1- 6. doi:10.1111/joor.13441