To investigate trends in the incidence of Parkinson’s disease (PD) between 2006 and 2016.

Changing epidemiological trends have been reported in Parkinson’s disease.^{1, 2}This may account for the conflicting reports regarding the incidence and prevalence of PD. There are reports of increases in incidence in some countries with high earning.^2-4 Others did not confirm an increase or report a decrease. The explanation for the varying incidence and prevalence rates suggests that the risk factors for PD vary between countries, by sex, time periods² and possibly coding systems.⁵ We used different codes to investigate changes in the incidence and prevalence of Parkinson’s disease between 2006 and 2016 using data from a large UK primary care database-The Health Improvement Network (THIN). 

Design: Cohort study in The Health Improvement Network (THIN): a large UK primary care database. 

Study Participants: Individuals actively registered with a practice within THIN aged 50 years and over.

Measures of outcome: The incidence of Parkinson’s disease between 2006 and 2016 using different case definitions: 1)PD diagnostic Read code; 2) PD diagnostic Read code OR symptom Read code; 3) PD diagnostic Read code OR symptom Read code and OR  at least 1 antiparkinsonian drug prescription; 4) PD diagnostic Read code OR symptom Read code plus at least 2 antiparkinsonian drug prescriptions. The effect of age, sex and social deprivation on these measures were investigated.

The overall crude incidence of PD for people over 50 years has increased in recent years. The rates increase with increasing age and as expected, higher in men.

There is increasing diagnosis of PD in primary care setting.