Action tremor associated with higher mortality across three Danish cohorts

Researchers examined the association between action tremor and all-cause mortality in three Danish population-based cohorts, using nationwide register follow-up and Cox regression with age as the time variable. The cohorts included 3,487 people with outpatient hospital-diagnosed essential tremor (ET), a twin study with spiral-based tremor assessment in 2,029 individuals, and 2,472 people reporting tremor in the Danish Symptom Cohort. Controls were matched in the register and symptom cohorts.

Hospital-diagnosed ET was associated with higher mortality than in matched controls (hazard ratio [HR], 1.37; 95% CI, 1.27–1.46). In the twin cohort, high Archimedes spiral scores indicating symptomatic action tremor were associated with an HR of 1.67 (95% CI, 1.42–1.97) versus scores of 0–2; higher scores were also associated with progressively lower survival. Self-reported tremor was associated with an HR of 1.56 (95% CI, 1.38–1.75), a finding robust to adjustment for alcohol use.

The consistency across cohorts and tremor assessments supports action tremor as a possible marker of underlying health vulnerability. The observational results do not establish causation or explain the mechanisms, and the abstract does not report the full covariate adjustments or subgroup details.