Long-term night shifts can increase risk of atrial fibrillation, CAD: Study
China: Long-term night-shift work increases the risk of atrial fibrillation and coronary heart disease but not stroke or heart failure, show results from a cohort study.
Whether decreasing the night shift work frequency and duration improves heart health during working life and beyond remains to be seen, the authors wrote in the European Heart Journal.
Atrial fibrillation (AF) is the most common arrhythmia managed in clinical practice. This occurs often as a cause or consequence of heart failure. A 2017 study showed AF to be prevalent in∼37.6 million people worldwide, including 3 million people with new-onset AF and 287 000 people who died from AF in 2017.
The American Heart Association has stated the importance of primary and secondary prevention of AF through intervention in lifestyle and risk factors (including sleep apnea, obesity, diabetes, and other modifiable lifestyle-related factors). Several of the risk factors have been associated with AF occurrence. Considering the increasing prevalence of AF, there is a need for studying its novel risk factors.
Against the above background, Ningjian Wang, Shanghai JiaoTong University School of Medicine, Shanghai, China, and colleagues aimed to test whether current and past night shift work were associated with incident atrial fibrillation using the cohort of 283 657 participants from the UK Biobank (UKB). Also, they determined whether this association was modified by the genetic vulnerability. Its associations with coronary heart disease (CHD), stroke, and heart failure (HF) were measured as a secondary aim.
The researchers obtained current and lifetime night shift work information. Weighted genetic risk score for AF was calculated. During a median follow-up of 10.4 years, 5777 incident AF cases were documented.
The research yielded the following findings:
- From 'day workers', 'shift but never/rarely night shifts', and 'some night shifts' to 'usual/permanent night shifts', there was a significant increasing trend in the risk of incident AF.
- Usual or permanent night shifts were associated with the highest risk [hazard ratio (HR) 1.16].
- Considering a person's lifetime work schedule and compared with shift workers never working nights, participants with a duration over 10 years and an average 3–8 nights/month frequency of night shift work exposure possessed higher AF risk (HR 1.18 and HR 1.22 respectively).
- These associations between current and lifetime night shifts and AF were not modified by genetic predisposition to AF. Usual/permanent current night shifts, ≥10 years and 3–8 nights/month of lifetime night shifts were significantly associated with a higher risk of incident CHD (HR 1.22, HR 1.37, and HR 1.35 respectively). These associations in stroke and HF were not significant.
"Our findings found that both current and lifetime night shift exposures were associated with increased AF risk, regardless of genetic AF risk. Night shift exposure also increased the risk of CHD but not stroke or HF," wrote the authors. "Whether decreasing night shift work frequency and duration might represent another avenue to improve heart health during working life and beyond warrants further study."
Reference:
The study titled, "Long-term night shift work is associated with the risk of atrial fibrillation and coronary heart disease," is published in the European Heart Journal.
DOI: https://academic.oup.com/eurheartj/advance-article/doi/10.1093/eurheartj/ehab505/6347324
