According to UK National Screening Committee, screening is a public health service in which members of a defined population, who do not necessarily perceive that they are at risk of, or are already affected by, a disease or its complications, are asked a question or offered a test to identify those who are more likely to be helped than harmed by further tests or treatment to reduce the risk of disease or its complications. In Japan, the screening program to detect and control risk factors for stroke and coronary heart disease are established. Sensitivity, specificity and ROC curves should be applied to a test with continuous variable and a detectable preclinical phase of cancer. The only design that effectively eliminates the effect of lead time, length time, overdiagnosis and selection biases is the randomized controlled trial, but only if person-years mortality is used as the endpoint. In Japan, practically, the case-control study is a second-best method. In screening, those who are approached to participate are not patients and most of them do not become patients. The screener must build up a core of ethical principles that govern the relationship between screenee and screener like that between patient and physician.
Chronic obstructive pulmonary disease (COPD) is a progressive disease and its mortality has rapidly increased. Early diagnosis and early management of COPD is very important for the reduction of mortality. The prevalence of COPD in Japan is reported to be 8.6%, but most of the patients were not diagnosed. Among undiagnosed COPD patients, more than half patients go to clinics with other diseases. Among the patients who are 40 or older and go to clinics with non-respiratory diseases, the prevalence of COPD is 10.3%. When diagnosed with post-bronchodilator condition, the prevalence was 8.7%. Patients with liver diseases were significantly higher prevalence of COPD than the patients with other diseases. As liver disease might be one of the risk factors of COPD, patients with liver diseases should be encouraged to perform spirometry for early detection of COPD. As early diagnosis and early management of COPD is very important, more aggressive intension to diagnosis of COPD in primary care doctors is desired.
COPD is recognized as a preventable and treatable disease now. However, it is well known that few numbers of patients with COPD is diagnosed and treated in Japan. One of reasons is no spread of spirometry in the institutions of primary care and health care. The spread of spirometry is an important awaiting solution, because spirometry only can discover newly and early COPD patients. In addition, we have several problems. First, parameters used in spirometry are often difficult to understand in non-specific respiratory physician and general people. Second, technique of spirometry is needed the efforts of subjects tested. Third, in general lung health might be concerned less than cardio-vascular health and metabolic syndrome. A new concept to understand about lung health easily and impressively should be needed. That is “lung age” in accordance with lung function. The concept of “lung age” has been proposed as a way of making the results of lung function test more familiar to the public. I hope the concept of “lung age” contribute that a number of patients with COPD will be discovered and treated, and also many smokers will resolve to stop smoking in Japan.
In 2009, the Japanese Society for Helicobacter Research recommended that all patients infected with H. pylori should be given “Recommendation Grade A” for eradication therapy, stating “There is strong scientific evidence to suggest that eradication should be recommended even in cases where H. pylori infection is not concomitant with specific diseases”. According to recent figures published by the National Cancer Institute, some 30-50％ of the entire Japanese population are carriers of H. pylori, and cancers (including sarcomas) occur in 1-2％ of them. In other words, more than 1.2 million people all over Japan are exposed to the risk for gastric cancer or gastric lymphoma caused by H. pylori. H. pylori is also involved in a wide variety of other diseases. But while H. pylori is without doubt “bad bacteria”, we can almost definite and easily reduce their risks if we want to. Without eradication therapy, however, not only will people continue to be infected throughout their lives and succumb to various diseases, but the infection will also be passed on to our children and grandchildren, mainly via the maternal line. This paper gives a commentary based on available evidence, from the point of view that “H. pylori must be eradicated”.
My opinion is that eradication of Helicobacter pyroli should not be necessary. The first reason is the risk of side effect of antibiotics for eradication. The second reason is the risk of developing reflux esopahagitis and gastroesopageal reflux disease. These diseases aggravate QOL of the patients. The third reason is the risk of Barrete's esophagus and Barette's esophageal cancer. The fourth reason is the risk of erosive gastritis and duodenitis. The last reason is the risk of developing obesity and of hyperlipidemia. They induce the cardiovascular disease. Prognosis after eradication of H. pyroli in short term was reported very good, but the prognosis after eradication of H. pyroli in long term was not reported. It is necessary to evaluate of prognosis after H. pylori eradication in long term. I emphasize that the H. pylori eradication does not improve the prognosis of the patients with infection of H. pyroli. My opinion is that eradication of Helicobacter pyroli should not be necessary.
As shown in the MEGA study (Management of Elevated Cholesterol in the Primary Prevention Group of Adult Japanese Study) designed to evaluate the effect of low dose of pravastatin (8.3 mg/day, on average) in the primary prevention of coronary artery disease (CAD) in Japanese subjects, some Japanese subjects were found to be especially sensitive to statin therapy. The suppressive effect of statins on coronary plaque progression was more marked in the study conducted in Western subjects than in previous trials in Western subjects. The responses of coronary atherosclerosis to statin treatment might differ markedly between Japanese and Western subjects. Thus, a beneficial reduction in the risk of CAD might be achieved with a small improvement in the lipid profile. There seems to be an urgent need to gather evidence regarding the effects of statins on the regression of coronary atherosclerosis and the inhibition of ischemic heart events in Japanese patients who show favorable sensitivity to statins.
Recently, it has become possible to diagnose unruptured cerebral aneurysm, owing to the development of diagnostic imaging techniques such as magnetic resonance angiography. However, the natural history and optimal treatment for unruptured cerebral aneurysm remain unknown. In Japan, the Unruptured Cerebral Aneurysm Study of Japan (UCAS-Japan) is now on-going. Preliminary results indicate that the overall annual risk of rupture is about 1%, and factors that are associated with increased risk of rupture include location and size of the aneurysm. The guidelines for Brain Dock 2008 recommend surgical indications for unruptured aneurysm. These are as follows: 1) patient's life expectancy is 10～15 years, 2) aneurysm size is over 5～7 mm, 3) aneurysm is located in the posterior circulation, the anterior communicating artery or the internal carotid-posterior communicating artery in cases of aneurysm size less than 5～7 mm, 4) symptomatic unruptured aneurysm, 5) irregularly shaped aneurysm, 6) aneurysm where the ratio of the dome to the neck is large. For patients with conservative treatment, periodic observation with imaging devices, control of hypertension and no smoking are required. We have have adopted these guidelines. Currently, we consider surgery is the treatment of choice for unruptured aneurysm, and the second choice is intravascular treatment. For aneurysm located in the paraclinoid IC or posterior circulation, we recommend intravascular treatment.