This new epidemic must occur because of risk factors much different from the traditional hunting territory of nephrology, immunologic diseases, primary glomerular diseases or genetic diseases . Collectively,these conditions have a 3:1000 prevalence which is far less than the 10% prevalence which emerged in surveys in the USA and in other countries. The disease underlying this epidemics is nephrosclerosis i.e. nephron obsolescence triggered by risk factors responsible alo for the CV diseases epidemics: obesity, type-2 diabetes , hypertension and smoking.
Not only a very risky condition but also that the epidemic may be in an expanding phase
One out 33 at the age of retirement and 1 out 20 at eighty…
Prostate cancer screening and early detection
Introduction
The issue of whether men should get regularly tested for prostate cancer is highly controversial and all too often gives rise to very strong emotions. For some very obvious reasons those patients who have been diagnosed early and successfully treated for prostate cancer clearly believe in the widespread use of “screening.” On the other hand, two large, randomized, but certainly flawed clinical trials have shown that such widespread, population-based “screening” has (at best) limited impact on the long-term, average survival of men in a defined population.
People often get confused about the difference between screening for prostate cancer and early detection of the disease. It happens to professionals and to patients. Let’s see if we can help to make the difference clear.
The Brownsville Experiment
Dr Brown, a urologist, wants to find how many men in Brownsville have prostate cancer.
The first year — Dr Brown decides that in order to answer his question he will give a free digital rectal examination (DRE) and PSA test to every fifth man over 40 years old who walks past his office on main street on a Saturday morning in May. He then gives a biopsy to every man with either a positive DRE or a PSA level > 2.5 ng/ml. In other words, these men are picked completely at random — except that they must walk past his office and be over 40. This is a true, population-based, prostate cancer screening program. The men have been selected at random from all men in Brownsville that day, and they don’t necessarily even think that they should be having a prostate cancer test.
The second year — A screening program like the one he does in the first year takes a lot of effort, so the next year Dr Brown decides just to offer a free DRE and PSA test to any man over 40 who comes to his office on the same Saturday morning in May and asks to be tested, and then to biopsy the men according to the same criteria as in year 1. So he puts an ad in his local Brownsville newspaper. This year, the people who get the DRE and the PSA test have selected themselves for some reason. Maybe they just think its time they had a PSA test. Maybe they have had to get up a few times too often in the middle of the night. Maybe their wife told them it was high time they had a prostate cancer test. Or maybe they just thought that they’d have the tests while they were free. Some physicians now call this case finding. It certainly isn’t a true screening initiative, because the tests aren’t being given at random and the men who get the tests have selected themselves.
The third year — Finally, the third year, Dr Brown decides he isn’t going to give anything away for free. Instead, he will encourage every man over 40 who comes to his office to have a DRE and a PSA test, regardless of their symptoms. His justification for this is that if they have come to see him — a urologist — there is good reason to think that they may have a urological disorder, including prostate cancer. This is true early detection. In other words, Dr Brown is going to do his best to find prostate cancer in any patient who comes to see him, but he isn’t going to go out of his way to look for patients with the disease.
Prostate cancer is one of the leading causes of death from malignant disease among men in the developed world. One strategy to decrease the risk of death from this disease is screening with prostate-specific antigen (PSA); however, the extent of benefit and harm with such screening is under continuous debate.
METHODS:
In December, 1994, 20,000 men born between 1930 and 1944, randomly sampled from the population register, were randomised by computer in a 1:1 ratio to either a screening group invited for PSA testing every 2 years (n=10,000) or to a control group not invited (n=10,000). Men in the screening group were invited up to the upper age limit (median 69, range 67-71 years) and only men with raised PSA concentrations were offered additional tests such as digital rectal examination and prostate biopsies. The primary endpoint was prostate-cancer specific mortality, analysed according to the intention-to-screen principle. The study is ongoing, with men who have not reached the upper age limit invited for PSA testing. This is the first planned report on cumulative prostate-cancer incidence and mortality calculated up to Dec 31, 2008. This study is registered as an International Standard Randomised Controlled Trial ISRCTN54449243.
FINDINGS:
In each group, 48 men were excluded from the analysis because of death or emigration before the randomisation date, or prevalent prostate cancer. In men randomised to screening, 7578 (76%) of 9952 attended at least once. During a median follow-up of 14 years, 1138 men in the screening group and 718 in the control group were diagnosed with prostate cancer, resulting in a cumulative prostate-cancer incidence of 12.7% in the screening group and 8.2% in the control group (hazard ratio 1.64; 95% CI 1.50-1.80; p<0.0001). The absolute cumulative risk reduction of death from prostate cancer at 14 years was 0.40% (95% CI 0.17-0.64), from 0.90% in the control group to 0.50% in the screening group. The rate ratio for death from prostate cancer was 0.56 (95% CI 0.39-0.82; p=0.002) in the screening compared with the control group. The rate ratio of death from prostate cancer for attendees compared with the control group was 0.44 (95% CI 0.28-0.68; p=0.0002). Overall, 293 (95% CI 177-799) men needed to be invited for screening and 12 to be diagnosed to prevent one prostate cancer death.
INTERPRETATION:
This study shows that prostate cancer mortality was reduced almost by half over 14 years. However, the risk of over-diagnosis is substantial and the number needed to treat is at least as high as in breast-cancer screening programmes. The benefit of prostate-cancer screening compares favourably to other cancer screening programs.
FUNDING:
The Swedish Cancer Society, the Swedish Research Council, and the National Cancer Institute.
In order to be cost-effective the
SCREENING FOR MICROALBUMINURIA HAS A 76%SENSITIVITY AND 96% SPECIFICITY
Not only low risk for CKD but also low risk for CV disease (75% of individuals in this cohort had a risk for CV events <1% /year
The best attempt ever made to test the cost effectiveness of screening policy
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