women who get beaten up at home are more vulnerable to asthma than those not subjected to domestic violence, a study says. The findings have been corroborated by social scientists working on domestic violence in India.

Domestic violence is a significant trigger for asthma, the researchers reported after a cross-country survey of Indian women exposed to household abuse. The research team, including scientists from the Harvard School of Public Health and Harvard Medical School, analysed data from the Indian National Family Health Survey of 1998-99 to conclude that the women who had then reported some kind of domestic violence were more susceptible to being asthmatic than those who had not undergone domestic violence. Their findings were published in the International Journal of Epidemiology on February 28, 2007.

With help from a national women's rights body, Down To Earth found two women who were suffering from domestic violence-triggered asthma. On condition of anonymity, the women, one from Rajasthan and the other from Tripura, conceded they became asthmatic after years of physical abuse at home. The woman from Tripura said she realised the problem only after being subjected to physical abuse for about 10 years.
Correlation The risk of a woman subjected to domestic violence getting asthma was 26 per cent to 37 per cent more than one who has not been, the team found. "Smoking, which is a well known risk factor for asthma, increases the risk of being asthmatic by 54 per cent. Domestic violence captures approximately half to three-fourth of the effect captured by smoking,' says S V Subramanian of the Harvard School of Public Health.

In homes that experienced any form of domestic violence, the risk of being asthmatic increased by 15 per cent to 19 per cent for all members living there. It was particularly strong for children under five, an age when asthma typically appears.
How it works How does violence trigger asthma expression? Exposure to violence affects a person's mental state and can cause an attack of asthma by upsetting nervous and immune mechanisms, Subramanian says.

Violence can increase smooth muscle tone in the lung, which in turn may mediate emotionally-induced bronchial constriction. Agrees Abraham Peedicayil, head of the Obsteristics and Gynaecology department of Christian Medical College, Vellore. "I have seen in many patients that psychological stress including domestic violence can trigger or exacerbate asthma,' he says.

The Indian study reinforces the association between domestic violence and asthma found in studies in the us and Australia, Subramanian says, adding: "Like most diseases, asthma is also socially patterned, with lower socio-economic groups, on average, being more burdened.'

"Using domestic violence as a marker of stressful psychological circumstances for those who directly experience violence and those who witness it, we investigated the relationship between stress and asthma prevalence,' Subramanian says.
Tip of the iceberg The researchers, however, did experience limitations of measuring asthma based on the family health survey figures. "In the national family health survey, no effort had been made to clinically test for asthma or inquire whether the response of individuals was based on a physician's diagnosis. The figures seem to underestimate asthma prevalence compared to other studies in India, including those from the International Study of Asthma and Allergies in Childhood,' he said.

Researchers working on domestic violence agree that such ailments are common. These figures might, however, just be the tip of the iceberg, says Anita Raj, an associate professor at the Boston University School of Public Health. Moreover, domestic violence goes unnoticed when it has psychological dimensions rather than purely physical manifestations, she says.

The dataset used for the survey found a higher prevalence of asthma among women in the northeastern states in comparison to the rest of India. "However, the relationship between domestic violence and asthma is pretty much a national phenomenon and has no striking regional variations,' Subramanian said.