SINGAPORE - Migraine sufferers caused some $1.04 billion in economic losses in Singapore last year, mostly due to lost productivity, a local study has found.

Productivity loss made up 80 per cent of the cost, with the remaining 20 per cent attributed to healthcare costs, such as medical tests and consultations.

People who experienced these chronic headaches also missed an average of 9.8 work days a year, and for those who continued working, the symptoms greatly reduced their ability to perform tasks, amounting to productivity loss of 7.4 days each year.

A migraine often progresses through several stages, which include symptoms such as constipation, irritability and visual disturbances, before the actual headache occurs.

It lasts between four and 72 hours, and tends to be more common in adult women than men due to hormonal changes.

Migraines mostly affect 30- to 40-year olds, with approximately 90 per cent of migraine sufferers experiencing their first attack before 40.

The overall lifetime prevalence of headache in Singapore is reported to be 82.7 per cent, of which migraines make up 9.3 per cent.

More than 600 full-time Singapore workers who suffered from migraines were surveyed online for the study, Economic Burden of Migraine in Singapore, which was conducted by Duke-NUS Medical School and the pharmaceutical company Novartis.

They were 38 years old on average, mostly Chinese, married and had tertiary education qualifications at the minimum.

Most were in managerial positions (60 per cent), with the remaining in clerical jobs, semi-skilled or self-employed.

Researchers found that those who had migraines on four to 14 days each month incurred a per capita cost of $14,860 last year. The cost was $5,040 for those who had migraines on only three or less days each month.

Dr Jonathan Ong from the National University Hospital (NUH) said that a total of 100 new patients turn up every month at the clinic for headache disorders at the hospital and Ng Teng Fong General Hospital. That figure has been increasing by about 10 per cent each year.

"It is not surprising because we are increasingly living in a stressful environment, being an Asian country - we're very work-driven, goal-orientated, spending longer hours at work, and stress is a major trigger for migraines," he said.

Migraine is linked to certain medical conditions such as depression and anxiety, cardiovascular disease, nasal or sinus inflammation, and can also be triggered by the environment, emotions and food.

"What's worrying is that our study found that approximately one in four patients in Singapore did not seek medical treatment for their migraine. For those who do try to manage the condition, they typically resorted to acute medications which may not be the most effective strategy in the long term, adding to their overall healthcare costs," said Dr Ong, who is a consultant in NUH's Division of Neurology and president of the Headache Society of Singapore.

Dr Eric Finkelstein from Duke-NUS Medical School said that migraines have long-term detrimental effects on people's work, such as affecting their career progression, as well as on their home lives.

At 41 per cent, medical tests made up a big proportion of the healthcare cost, followed by alternative medications (18 per cent), consultations (16 per cent), hospitalisations (13 per cent) and medications (11 per cent). "When it comes to migraines, most of the medical cost is not actually making people better," said Dr Finkelstein, professor in the school's Health Services and Systems Research Programme.

"It's actually wasted money; it's not effective treatment."

Researchers hope the results will raise awareness about migraines, such that more people can be properly diagnosed and that workplaces will be more understanding and accommodating to sufferers.

"When awareness increases, then policymakers will start to realise that migraine is a chronic disease and possibly allow patients to use Medisave and Medifund to access the latest treatments if conventional treatments don't work," said Dr Ong, adding that they plan to take the results to the Ministry of Manpower, the Ministry of Health and the Health Promotion Board.