Circadian rhythm disruption increases risk of Parkinson's disease in elderly: JAMA
San Francisco: Disruption of circadian rhythmicity in older men may increase the risk of Parkinson's disease (PD), a recent study in the journal JAMA Neurology has found.
Circadian rhythm disruption is very common in older adults, especially among those having neurodegenerative diseases, including Parkinson's disease (PD). But whether circadian disruption could be a prodrome for PD is not clear.
Yue Leng, Department of Psychiatry, University of California, San Francisco, and colleagues determined the association between rest-activity rhythm (RAR) and incident PD risk and also explored whether this association is independent of nighttime sleep disturbances.
The ancillary sleep study of the longitudinal cohort Osteoporotic Fractures in Men Study (MrOS) was conducted from December 1, 2003, to March 31, 2005. Of the 3135 community-dwelling men enrolled in the MrOS sleep study, 3049 had technically adequate RAR data; of these, 119 were excluded for having prevalent PD or missing incident data, leaving 2930 men without PD at baseline. Data were analyzed from February 1 through August 31, 2019.
Exposures included twenty-four-hour RAR parameters (amplitude, mesor, robustness, and acrophase) generated by wrist actigraphy–extended cosinor analysis.
The primary outcome was Incident PD based on physician diagnosis. Among the 2930 men included in the analysis (mean [SD] age, 76.3 [5.5] years), 78 (2.7%) developed PD during 11 years of follow-up.
Key findings of the study include:
- After accounting for all covariates, the risk of PD increased with decreasing circadian amplitude (strength of the rhythm) (odds ratio [OR] per 1-SD decrease, 1.77), mesor (mean level of activity) (OR per 1-SD decrease, 1.64), or robustness (how closely activity follows a cosine 24-hour pattern) (OR per 1-SD decrease).
- Those in the lowest quartile of amplitude, mesor, or robustness had approximately 3 times the risk of developing PD compared with those in the highest quartile of amplitude (OR, 3.11), mesor (OR, 3.04), and robustness (OR, 2.65).
- The association remained after further adjustment for nighttime sleep disturbances and duration in the lowest compared with the highest quartile (OR for amplitude, 3.56; OR for mesor, 3.24; and OR for robustness, 3.34).
- These associations were somewhat attenuated, but the pattern remained similar after excluding PD cases developed within 2 years after baseline in the lowest compared with the highest quartile (OR for amplitude, 2.40; OR for mesor, 2.76; and OR for robustness, 2.33 ).
- Acrophase was not significantly associated with risk of PD.
"In this cohort study, reduced circadian rhythmicity was associated with an increased risk of incident PD, suggesting it may represent an important prodromal feature for PD. Future studies are needed to determine whether circadian disruption could also be a risk factor for PD and whether strategies to improve circadian function affect the risk of PD," concluded the authors.
The study, "Association of Circadian Abnormalities in Older Adults With an Increased Risk of Developing Parkinson Disease," is published in the journal JAMA Neurology.
