# Declining incidence of Parkinson’s disease in Israel (2002–2021)

## TL;DR

Parkinson’s disease incidence in Israel decreased significantly from 2002 to 2021, especially among older people, possibly due to better diagnosis and improved living conditions.

## Contribution

First assessment of Parkinson’s disease incidence trends in Israel using registry data and statistical analysis.

## Key findings

- Age-adjusted incidence rates of Parkinson’s disease declined 2.8-fold over 20 years in Israel.
- Females experienced a faster decline in Parkinson’s disease incidence compared to males.
- The decline in incidence was most pronounced among the very elderly population in both sexes.

## Abstract

The results of investigations of the trends of the incidence of Parkinson’s disease (PD) over time in numerous developed countries showed that aging and increasing life expectancy are leading to an increase in both. We investigated the crude and age-adjusted incidence rates (AAIRs) of PD based upon registry data of Israel’s largest health maintenance organization between 2002 and 2021 according to joinpoint regression. We applied an age-period analysis to further identify patterns of AAIR changes, and calculated longitudinal age curves of PD rates (“local drift”) as well as annual change of the expected age-specific and expected age-adjusted AAIR (“net drift”). The overall AAIR of PD declined from 57 ± 1.0 to 20.3 ± 0.5 per 100,000 over 20 years, representing a 2.8-fold decrease. The PD incidence decreased more rapidly among females (average annual percent changes [AAPC] − 5.3%, 95% confidence interval [CI] − 6.0–4.6, p < 0.001) than among males (AAPC − 4.5, 95%CI − 5.3–3.7, p < 0.001). AAIRs peaked at 209.9 (CI: 193.0–228.5) per 100,000 at a median age of 77.5 vs. 374.9 (CI: 350.9–400.5) years in females and at a median age of 82.5 years in males. AAIRs gradually declined in males to 63.3 (CI: 52.2–84.1) per 100,000 and in females to 29.7 (CI: 21.4–41.1) per 100,000 for the 97.5-year-old group in both sexes. This first assessment of the trends of the incidence of PD in Israel documented its progressive decline from 2002 to 2021, especially among the very elderly. This decline may reflect refined diagnostic capabilities and enhanced health, quality of life and environmental conditions in Israel.