The condition known as Resistant Hyper-tension increases stroke risk by 35 percent in women and 20 percent in elderly patients, according to new research.

"Patients with hyper-tension that does not respond to conventional drug treatments, called resistant hyper-tension, are at a higher risk of cardio-vascular morbidity and mortality," Dr Kuo-Yang Wang from Taiwan told the gathering Sunday at the European Society of Cardiology (ESC) Congress 2014 in Barcelona, Spain.

Researchers reveiwed records of 111,986 Taiwanese patients from 2000 to 2011. Some 16,402 (14.6 percent) patients had resistant hyper-tension.

The risk of major adverse cardio-vascular events (MACE) in patients with resistant hypertension and non-resistant hypertension was analysed.

The researchers found that 11,856 patients experienced MACE in the average 7.1 year follow up period.

Patients with resistant hyper-tension had a 17 percent increased risk of MACE compared to those with non-resistant hypertension.

The findings suggest that gender and age should be added to the risk stratification of resistant hyper-tension to enable appropriate treatment decisions, Dr Wang concluded.