Night shift workers are at an elevated risk of developing atrial fibrillation (AFib), according to new research published in the European Heart Journal. They also face a greater risk of coronary heart disease (CHD), but not stroke or heart failure (HF).
The study's authors cited previous data that suggested shift work, and night shift work in particular, could have an adverse impact on individual health and organ function. Information on the association between night shifts with AFib, however, was harder to find.
To learn more about that topic, the group analyzed 286,353 salaried or self-employed participants from the UK Biobank database.
While 283,657 of those participants had no prior history of AFib when they enrolled, 276,009 were presented with no signs of CHD, stroke or HF.
During a median follow-up period of 10.4 years, 5,777 incidents of AFib were reported. Researchers adjusted for age, sex, ethnicity, education, socioeconomic status and several other key factors, determining that working night shifts on a "usual or permanent basis" was associated with a 12% greater risk of AFib.
That risk increased to 18% after ten or more years for those who worked a night shift for their entire life.
In addition, among participants who worked an average of three to eight night shifts a month for ten or more years, the risk of AFib climbed to 22% compared to daytime workers.
Researchers also found that the risk of developing CHD increased significantly for current night shift workers (22%), individuals working night shifts for ten years or more (37%) and individuals working a lifetime of three to eight night shifts per month (35%).
In addition, women were more susceptible to AFib than men when working night shifts for more than ten years; their risk increased by 64%.
“Although a study like this cannot show a causal link between night shifts and AFib and heart disease, our results suggest that current and lifetime night shift work may increase the risk of these conditions,” senior author Yingli Lu, MD, PhD, from the department of endocrinology and metabolism at Shanghai Ninth People’s Hospital and JiaoTong University School of Medicine in China, said in a prepared statement. “Our findings have public health implications for preventing AFib. They suggest that reducing both the frequency and the duration of night shift work may be beneficial for the health of the heart and blood vessels.”
The authors described their analysis as “novel” because it linked genetic and observational data in a large population with detailed each participant's current working habits and lifetime employment history. They also have more research planned in the years ahead.
“We plan to analyze the association between night shift work and AFib in different groups of people,” Lu added. “This may strengthen the reliability of these results and serve as a warning to groups working in certain types of occupations to get their hearts checked early if they feel any pain or discomfort in their chests.”
Read the full study here.