The Hong Kong Kidney Foundation, Hong Kong Society of Nephrology and Hong Kong Association of Renal nurses, which offered health checks to over 1,600 people last month with a median age of 65 found 73 percent of them have hyperlipidemia, but were unaware of it.

They found 68 percent and 56 percent of the people have high blood sugar and hypertension respectively, but were clueless, adding that 36 percent of them were unaware that they are overweight.

Currently, more than half of the patients with end-stage renal disease who need kidney dialysis have diabetes and around 10 percent of them have hypertension.

It is estimated that one million Hongkongers - one-seventh of the population - have hidden kidney diseases.

They urged people to visit doctors for early diagnosis and treatment, as it would endanger their health and could increase the burden on the local healthcare system.

Attending an event hosted by the three medical associations yesterday, Hospital Authority chief Tony Ko Pat-sing said many people believe it is harmless to be slightly overweight, but they ignore the risks that come with it.

Many younger people have started developing chronic illnesses over the past 10 years, Ko said.

"Hong Kong records more than 1,000 new cases of end-stage renal disease per year, bringing the tally of renal failure patients to 7,000 now. Nearly 2,000 patients are waiting for kidney transplants, which is a worrisome situation."

He said managing chronic diseases to prevent serious illnesses is critical than treatment.

Secretary of Health Lo Chung-mau said that people should adhere to exercise to live a healthy life.

Many private medical institutions provide kidney dialysis services, however, people should still try to prevent the illness, Lo said.

Lo added that the government has revealed its primary healthcare blueprint, which aims to provide Hongkongers their family doctor for early detection and management of diseases.

Vice-chairman of the Department of Health's Task Group on Promotion of Physical Activities, Lobo Louie Hung-tak, said regular exercise can reduce the risk of developing kidney diseases by 10 percent.

Louie urged people aged above 60 to walk 8,000 steps a day and 10,000 for those below 60 to improve their health.

Director of Health Ronald Lam Man-kin recommends people use the staircases instead of the lifts as a way of exercising.

They should eat healthy food, including fruits and vegetables, while lowering the intake of salt, sugar and oil, Lam explained.