Longer napping time linked to increased risk of Parkinson’s disease among older men
Older men who experience long napping durations and excessive daytime sleepiness (EDS) have greater odds of developing Parkinson’s disease (PD), a study suggests. This is not true for older men who report only EDS.
Researchers followed for 11 years 2,920 men (mean age 76 years) without a history of PD. Data on EDS (defined as having an Epworth Sleepiness Scale score >10) and objective naps (defined as ≥5 consecutive minutes of inactivity as measured by actigraphy) were collected.
PD risk was then compared across four groups, as follows: no EDS/napping <1 h/day (referent group; n=1,739, 59.5 percent), EDS/napping <1 h/day (n=215; 7.4 percent), no EDS/napping ≥1 h/day (n=819; 28.1 percent) and EDS/napping ≥1 h/day (n=147; 5.0 percent).
During the 11-year follow-up, 106 men developed PD. Multivariable logistic regression models showed that the risk of PD was higher in the groups of men who reported napping ≥1h/day alone and those who reported EDS/napping ≥1h/day (vs the referent group: odds ratios [ORs], 1.96; 95 percent CI, 1.25–3.08 and 2.52; 1.21–5.27, respectively). PD risk showed no association with EDS alone.
The associations were maintained in an analysis further adjusted for chronotype and circadian stability, or excluding PD cases identified within 2 years after napping measurements.
The present data indicate napping as a noticeable behaviour that may be useful as a prodromal sign of PD and aid in the early detection of individuals at high risk of developing the degenerative disorder, researchers said. This has important clinical implications, as early detection could help slow down or prevent PD progression in the long run.