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Q1: I am 70 years old in February – still working; in, I think, reasonable health, drink a bit (30-40 units a week), regular golfer (at least twice weekly) and at least one hour session twice weekly in gym. Immediate health concern is two to six urinations each night and when I have to go I really have to go or disaster. I also get pains in my lower right back, about waistline in the kidney area. I also wonder if I have any liver damage at all. I am prone to back pains that incapacitate me about once a year.

I am 5ft 10in tall, weigh 13st 12lbs – probably 10lbs or so overweight but stable. I think I eat a reasonably balanced diet with no obviously sweet things at all. Perhaps I should mention my sexual performance capability has declined significantly in the last year – I have always been very active.

I am interested in the screening program taken by Dr Stuttaford and am wondering why he did it – was it just research? Would I benefit by this, for example is it likely to point to any lifestyle changes I need to take since I am in the "end game" of life to improve quality and/or longevity? I have read that screening is a waste of time and feeds paranoia about ones health. I only go to a doctor if a really need to. Name and address withheld.

A1: As the reader of this question isn't my patient we can't deal authoritatively with his personal queries in detail, for this he should see his own doctor. However he has kindly given us an excellent summary of a case history that applies to hundreds of thousands of late middle-aged early old-aged men and we can and will discuss this in general terms.

The reader's exercise regime sounds fun and is therefore bound to be of benefit but it is not ideal. Ideally people should take brisk exercise every day unless the weather is inclement, either too hot, too cold (especially if there is a wind) or too muggy. In a temperate climate like ours this means that exercise can be taken most days. Brisk exercise is bracing enough to make conversation with a colleague difficult but not impossible. Preferably it should be about forty minutes a day, not necessarily all at the same time, but if a person is known to have any risk factors it should be over an hour's exercise, but again not necessarily at one go.

Golf is a wonderful pastime and is therefore an admirable hobby that provides fresh air and social contact. Unfortunately it is one of the few forms of exercise that can't be associated statistically with an increase in survival time, rather depressingly there is in fact a fractional increase in sudden death among golf players. This finding was studied in some detail around 10 to 15 years ago and was present even when allowance had been made for golf club parties, drinks at the 19th and the temptation to smoke. It was suggested that any increase in sudden death could be the result of some of the exercise taking place when the arms are above the head and the patient was concentrating and holding his breath. It is accepted that work above shoulder level by craftsmen is likely to produce angina in vulnerable people. Don't give up golf but take brisk walks too. The gym, like golf, is fun but unless it is done daily or at least four times a week it may not be very useful so far as increasing survival time. I would suggest that the reader's alcohol intake is almost ideal for a man of his height and weight, but the government would like to see it cut by 25 per cent.

The nocturnal frequency of urination, with urgency so that the reader has to rush, or there is a disaster, certainly warrants immediate investigations. The likelihood is that the symptoms are the result of benign hyperplasia (enlargement) of the prostate but this diagnosis cannot possibly be made without other investigations. Patients with a similar history to this reader's would normally have a urinary flow test to measure the speed and volume of the amount of urine passed. This is an easy test, no pain, no discomfort, merely peeing into a specially adapted container. This will let the reader's doctor know if his prostate is obstructing the passage leading from the bladder.

A doctor will also want, or in my opinion should want, a PSA blood test. This doesn't deliver a definitive diagnosis, it is not supposed to, but it does give a good indication of the likelihood of any enlargement of the prostate being the result of malignant, rather than benign changes. If a PSA is raised above three I always arrange for my patients to have a transrectal ultrasound and biopsy to exclude malignant change. Only by treating all cases of urinary tract problems in the ageing male seriously will the present monstrous death rate from cancer of the prostate in this country be brought into line with that experienced by men living in other western countries. Declining sexual prowess is often a symptom of prostatic enlargement whether benign or malignant. Not all benign enlargement of the prostate is inevitably treated with surgery, in fact it is now more usual to treat initially with tablets. Unexplained sudden deterioration in sexual performance is an indication for investigations to exclude diabetes and arterial disease.

I undertook the screening programme as a matter of individual research but I was also very aware when I accepted the invitation to the screening that it is in my opinion an extremely beneficial undertaking. By chance, like most visits to a screening line, it revealed some very welcome news and some less cheering - but no wholly unexpected. I was delighted to find that my liver was in good order with no evidence of fatty infiltration or cirrhosis, I was pleased that although in early adult life I had had a high blood pressure my coronary and cerebral arteries are in remarkably good order. Nor was there significant damage to my heart from having a high blood pressure at a time when doctors treated it inadequately. The screening confirmed a small aneurysm of my aorta, the main artery of the heart, that I have checked annually. It hasn't increased in size at all over the past ten years - very encouraging. Less reassuringly the screening showed that there had been an increased deterioration in my kidney function - most likely the result of irradiation for the treatment of prostate cancer - that had been faster than I would have expected. The deep X-ray treatment for the cancer of the prostate also probably accounts for a persistent slight anaemia that has been noted previously.

I am always very suspicious of attacks on screening. These often fly in the face of people's personal experience. Research has shown, for example, that only a very small proportion of people suffer from excessive anxiety about screening, especially if it is done as in most screening centres so that many of the results can be given immediately and the others within a day or two. The approach to screening is as much about philosophy and the estimation of relative risk and risk-benefit analysis as it is about medicine. It is for doctors to tell lay patients what the risks are and its potential benefits so that the patients can make their own minds up about the underlying philosophy. Doctors are not there to give doctors' orders but to advise.