Health: A Question of Health

WHAT IS Body Mass Index (BMI)?

BMI is a measurement of body size that combines height with weight. You can calculate it by taking your weight (in kilograms) and dividing it by your height (in metres) squared. For instance, if you weigh 73kg and are 1.9m tall, then you score a BMI of 20.2 and are of normal weight for your height. A BMI between 20 and 25 is considered normal. If your BMI is over 25, then you are considered to be overweight. You are obese if it is over 30.

WHENEVER I have my blood pressure checked, it is raised, but my GP thinks this is caused by "white coat hypertension". Is it necessary to treat this?

The phrase "white coat hypertension" was coined to describe people who have raised blood pressure only when they go to see a doctor. For these people, just the sight of a doctor's white coat is enough to put up their blood pressure. To find out whether you have high blood pressure that requires treatment, you could have ambulatory blood pressure monitoring. This is done with a portable device that measures your blood pressure automatically many times over a 24-hour period as you go about your normal activities. If your blood pressure is raised only when you see a doctor, then you do not need to have treatment.

WHAT CAN I do about excessive sweating? I cannot walk slowly for 10 minutes without sweat literally dripping from my head. My son suffers in exactly the same way. My doctor has no idea how to help. I realise that it is distressing, rather than life-threatening.

The fact that both you and your son have the same problem suggests an inherited problem in sweat regulation. Little research has been done into this distressing symptom. Increasing your fitness will probably help, and it is important that you are not overweight. Some patients with spinal injuries develop severe sweating symptoms, and a drug called propantheline bromide can help them. You may want to discuss the pros and cons of trying this with your GP.

MY 14-YEAR-OLD son has been advised to stop playing sport because he has painful swellings just below his kneecaps. Is there any treatment that will help this?

Your son is suffering from Osgood-Schlatter disease, a disorder that mostly affects teenagers who are physically active and play a lot of sport. The quadriceps muscles at the front of the thigh stretch over the kneecap and eventually attach themselves to the shin bone, just below the knee. However, in Osgood-Schlatter disease, this point of attachment becomes inflamed, swollen and painful. The problem is at its worst during growth spurts, and it normally disappears when a young person has stopped growing. The best treatment is to rest the knees when they start to become painful. Ice packs and supportive bandaging will also help the symptoms.

Please send questions to A Question of Health, `The Independent', 1 Canada Square, Canary Wharf, London E14 5DL; fax 0171-293 2182; or e-mail to health@independent.co.uk. We regret that Dr Kavalier cannot respond personally to questions