Anxiety Diagnosis After Age 50 Doubles Parkinson Disease Risk

Adults with anxiety vs those without anxiety have at least twice as high of a risk of developing Parkinson disease (PD), according to the findings of a study published in British Journal of General Practice.

The prevalence of anxiety is higher among patients with PD than the general population, however, it remains unclear whether individuals who present with incident anxiety are at elevated risk for PD.

Researchers from University College London sourced data for this study from the IQVIA Medical Research Database which includes data from the Health Improvement Network (THIN), a primary care database from 711 practices in the United Kingdom. Patients (N=987,691) aged 50-99 between 2008 and 2018 with a documentation of anxiety after 1 year or more of no anxiety documentation (n=109,435; 35% men) or without any documentation of anxiety (n=878,256; 37% men) were evaluated for PD onset and predictors for PD risk.

A total of 331 patients with anxiety were diagnosed with PD at a median of 4.9 (IQR, 4.0-9.6) years. Among individuals with anxiety, the incidence rate of PD was 1.02 (95% CI, 0.92-1.13) per 1000 person-years (py) vs 0.49 (95% CI, 0.47-0.52) per 1000 py among those without anxiety.

In the fully adjusted model, risk for PD was associated with anxiety (adjusted hazard ratio [aHR], 2.1; 95% CI, 1.9-2.4).

The risk for PD increased with age from an aHR of 3.2 for individuals aged 55-59 to 9.8 for individuals aged 90-94 compared with those aged 50-54.

Additional PD predictors included:

• tremor (aHR, 21.3; 95% CI, 14.4-31.5),
• rigidity (aHR, 5.1; 95% CI, 1.2-21.2),
• balance impairment (aHR, 4.2; 95% CI, 2.1-8.3),
• hypotension (aHR, 4.0; 95% CI, 1.7-9.7),
• constipation (aHR, 2.6; 95% CI, 1.9-3.6),
• sleep problems (aHR, 2.2; 95% CI, 1.5-3.2),
• cognitive impairment (aHR, 1.8; 95% CI, 1.1-3.1),
• fatigue (aHR, 1.8; 95% CI, 1.3-2.6), and
• depression (aHR, 1.7; 95% CI, 1.1-2.5).

Conversely, risk for PD was lower among women (aHR, 0.41; 95% CI, 0.34-0.50) and among individuals in the most deprived deprivation quintile (aHR, 0.60; 95% CI, 0.40-0.91).

Anxiety or other mental health outcomes may have been underrepresented in this study, as mental health status is generally under recorded in medical records.

“[T]here was a two-fold increase in risk of PD in patients with first presentation of anxiety aged >50 years. The clinical features of those who developed PD can help identify patients presenting with anxiety who are in the prodromal phase of PD,” the researchers concluded.