Asthma risk rises sharply for women working night shifts, warns study

Women on night shifts face up to 50% higher risk of asthma due to hormonal disruption and circadian imbalance, with postmenopausal women most vulnerable

A new UK study has found that women working night shifts face a significantly higher risk of developing moderate to severe asthma. Titled Increased risk of asthma in female night shift workers and published in ERJ Open Research, the study analysed data from over 274,500 participants. Led by researchers at the University of Manchester, the findings point to a strong gender-specific risk — one not observed in men — possibly due to hormonal differences and occupational exposures.

How does night shift work affect asthma risk?

The research found that women working permanent night shifts were around 50 per cent more likely to develop moderate to severe asthma compared to those working daytime hours. The likely culprit? Disruption of the body’s circadian rhythm — the internal clock that regulates sleep, hormones, and immune functions.

 

 

This disruption may interfere with testosterone levels, which previous research has linked to a protective effect against asthma. Since women naturally have lower testosterone, their risk rises when their hormonal balance is disturbed by night work.  What the data reveals  Researchers studied data from 274,541 individuals in the UK Biobank, a large biomedical database. Of the participants, 5.3 per cent had asthma, with 1.9 per cent suffering from moderate to severe forms — defined as needing a preventer inhaler plus at least one additional treatment such as oral steroids.

 

Participants were grouped based on work schedules: daytime-only, night-only, or rotating shifts. The highest asthma risk emerged in women working only night shifts.

Why postmenopausal women are especially at risk

The study further revealed that postmenopausal women not on hormone replacement therapy (HRT) and working night shifts had nearly double the risk of moderate to severe asthma compared to their daytime counterparts. This supports the theory that female hormones play a protective role and that their absence in menopause may leave women more vulnerable to asthma triggered by circadian disruption.

What should night-shift workers do?

Experts advise women working night shifts — especially those with a personal or family history of asthma — to monitor their respiratory health closely. Regular medical check-ups, discussing symptoms with healthcare providers, and making appropriate lifestyle changes can help manage or reduce risk. However, there are currently no specific asthma prevention guidelines tailored to night-shift workers.  For more health updates, follow #HealthWithBS 

This content is for informational purposes only and is not a substitute for professional medical advice.