|
- 现金
- 62111 元
- 精华
- 26
- 帖子
- 30437
- 注册时间
- 2009-10-5
- 最后登录
- 2022-12-28
|
HBV Journal Review
March 1, 2015, Vol 12, no 3
by Christine M. Kukka
PDF PDF (download)
Cholesterol and Type 2 Diabetes Drugs Markedly Lower Cancer Risk in Hepatitis B Patients
A large, ground-breaking study that followed 71,824 patients infected with the hepatitis B virus (HBV) from 2000 to 2008 found that those who took medium to high doses of metformin and/or statins had substantially lower rates of liver and other cancers.
The study, conducted by Taiwanese researchers and published in the February issue of the journal Medicine, examined the impact of:
Statins: Drugs taken to reduce triglycerides and cholesterol in the blood
And metformin: A drug used to treat patients in the early stages of type 2 diabetes.
There have been some studies that suggest statins reduce liver cancer risk in hepatitis B patients, however this large study that spanned eight years found a definite decrease in cancers in patients who took these drugs, especially at higher doses.
While the exact mechanisms that protect against cancer are not known, researchers suspect that statins and metformin decrease inflammation caused by HBV infection by altering the availability of lipids (fats) in the bloodstream.
"Changes in lipid metabolism can affect numerous cancer cellular processes, including cancer cell growth, proliferation, differentiation, and motility," the researchers wrote. As a result, the drugs appeared to prevent or slow development of liver, colon, breast, lung and pancreatic cancers.”
They reported: Hepatitis B patients taking only statins had a 52% reduced risk of all types of cancers and a 28% reduced risk of liver cancer, compared to HBV-infected patients who did not take statins.
Patients taking only metformin had an 82% reduction for all cancers and a 97% reduction for liver cancer. Higher doses of metformin provided the most protection.
The "synergistic effect" of the combined use of statin and metformin reduced colorectal cancer, breast cancer, and other cancers in young hepatitis B patients between the ages of 20 and 49," they reported. The drug combination also reduced lung, stomach, and cervical cancers in patients age 50 and older.
"The results of our study suggest that the incidence of cancer in patients with HBV infection can be reduced by utilizing preventive strategies," they wrote. "This is also the first article that suggests a dose–response effect and synergistic effect of statin and metformin use in reducing the incidence of all kinds of cancers."
Source: http://journals.lww.com/md-journal
/Fulltext /2015/02020/Cancer_Risk
_in_HBV_Patients_With_Statin_and.7.aspx
Hepatitis B Increases Risk of Stomach Cancer
Researchers have found higher rates of pancreatic and liver cancer in individuals infected with the hepatitis B virus (HBV), and now a new study finds a 50% increased risk of gastric (stomach) cancer among people with HBV.
According to the study published in the February 2015 issue of the British Journal of Cancer, Chinese researchers compared gastric cancer rates in a group of 580 HBV-infected individuals and a control group of 580 healthy individuals of similar age and gender.
People with chronic hepatitis B had gastric cancer rates that were about 49% higher than the control group. There were higher rates of gastric cancer even in patients with no family history of stomach cancer.
Even patients with resolved hepatitis B infections (who were negative for the hepatitis B surface antigen–HBsAg-negative)–remained at higher risk of gastric cancer than the control group.
"In addition, some synergistic effects between HBV infection and blood type A in gastric cancer were identified," researchers reported, noting that having blood type A appeared to also increase gastric cancer risk.
Researchers called for additional studies and research to determine why hepatitis B increased cancer in the digestive system.
Source: www.ncbi.nlm.nih.gov/pubmed/2569548
Unsafe Injections Caused 1.7 Million HBV Infections Worldwide in 2010
Health care providers’ re-use of syringes caused an estimated 1.7 million new HBV infections in 2010, according to a World Health Organization (WHO) report. In many developing countries, syringes are improperly sterilized and re-used to save money.
To stop unsafe injections, WHO is promoting universal adoption of “smart syringes,” that allow only one injection per syringe by the year 2020 to reduce transmission of hepatitis B and C and HIV infections worldwide. Smart syringes work by preventing users from pulling the plunger back up after it is depressed into the syringe to inject the medication.
HBV, which can remain infectious for days after it has dried on hard surfaces, is easily transmitted through reused syringes and medical equipment.
In the past century, unsafe injections have caused millions of bloodborne infections globally, especially in cultures that believe this fast delivery of medication is the most effective. In some regions, doctors can charge more for injecting medicine than dispensing it in pill form, which contributes to the spread of bloodborne infections when syringes are re-used.
In addition to causing 1.7 million hepatitis B cases, in 2010 unsafe injections caused:
Between 16,939 and 33,877 new HIV infections
And between 157,592 and 315,120 new hepatitis C infections, according to a June 2014 study published in the journal PLOS One.
In 2000, WHO estimated that unsafe injections caused 5%, 32% and 40% of new HIV, hepatitis B and hepatitis C infections respectively. After an intense global education campaign to educate providers about the dangers of unsafe injections, re-use of syringes declined markedly.
“Despite a 13% population growth, there was a reduction of 87% and 83% respectively in the absolute numbers of HIV and hepatitis C infections transmitted through injections,” they wrote. For hepatitis B, the reduction in new infections declined dramatically by 91% due in part to the additional impact of widespread hepatitis B immunization.
Source: http://journals.plos.org/plosone/article?
id=10.1371 /journal.pone.0099677
Source: www.npr.org/blogs/goatsandsoda
/2015/02/24/ 388785319/how-did-a-celibate
-82-year-old-buddhist-monk-contract-hiv
New Guidelines Require Doctors to Screen for Hepatitis B Before Starting Chemotherapy
New guidelines from the American Gastroenterological Association make it crystal-clear that doctors must screen patients for HBV infections before starting chemotherapy treatment, and they must use antivirals to prevent HBV reactivation in those currently or previously infected.
Despite clear evidence that immunosuppressive drugs, which weaken the immune system, often cause HBV to reactivate during cancer treatment, many doctors fail to screen patients for infection prior to starting chemotherapy. As a result, an HBV infection can reactivate, endangering the cancer patient’s fragile health.
“Preventing HBV reactivation in these patients involves screening those at risk, identifying patients for risk based on HBV (blood test results)... and consideration of prophylaxis (preventive treatment) with (antivirals),” the report's authors reported in the January issue of Gastroenterology.
Using recent studies, the authors attempted to clarify which patients should be screened and which should receive antivirals during chemotherapy to prevent HBV reactivation. They framed the guidelines in a question-and-answer format.
Should all patients be screened for HBsAg and the hepatitis B core antibody before starting immunosuppressive drugs? Yes, especially if they are at moderate- or high-risk of hepatitis B.
However, doctors have historically been poor predictors of hepatitis B risk in their patients. Many patients do not disclose drug use or sexual behaviors that could place them at high risk of HBV infection, and many doctors fail to test Asian-Americans and other ethnic groups who are at high risk of infection because of their countries of origin.
"...A cost-effectiveness study of HBV screening in the general population showed that screening is cost-effective even when the prevalence of HBV infection is as low as 0.3%," the experts pointed out.
Are antivirals needed in HBsAg–positive patients who need chemotherapy? Absolutely, according to the guidelines, because the risk of reactivation is extremely high.
Are antivirals needed for HBsAg-negative patients who have inactive hepatitis B? Yes. The guidelines recommend preventive antiviral treatment rather than simply monitoring patients to see if their hepatitis B reactivates. While the risk of reactivation is moderate in these patients, the guidelines still promote preventive antivirals.
Are antivirals needed if previously-infected patients test positive for the hepatitis B surface antibody? Researchers report HBV reactivation occurs in 4.3% of patients with surface antibody, but because there are so few studies into this subgroup of patients, the guidelines suggest doctors not use the presence of surface antibodies when making a decision to use antivirals during chemotherapy.
They should also not wait to see if viral load (HBV DNA) increases during chemotherapy before using antivirals.
Which antiviral should be used during chemotherapy? Should doctors prescribe the cheaper, older antivirals such as lamivudine (Epivir-HBV) that have high rates of drug resistance, or should they use new, more potent and expensive drugs such as tenofovir (Viread) or entecavir (Baraclude)? The guidelines suggest using the newer, more potent antivirals to prevent the risk of drug resistance.
Despite the lack of studies into the role of surface antibodies or viral load in assessing risk of HBV reactivation during chemotherapy, "...the recommendations ... represent a rigorous, evidence-based summary of extensive literature describing the prevention and treatment of HBV (reactive-ation)," researchers concluded. Reviewing these guidelines with patients, "...will facilitate effective shared decision-making with patients at risk for HBV reactivation," they concluded.
Source: www.gastrojournal.org/article/
S0016-5085 %2814%2901331-6/fulltext
Computer Reminders Effective at Prompting Doctors to Screen for HBV Before Starting Chemotherapy
As mentioned in the above article, many doctors fail to screen patients for past or present hepatitis B infections before prescribing immune-suppressing chemotherapy. However, a recent initiative using computerized reminders, improved screening rates markedly.
In the study, published in the February issue of PLoS One, doctors who were about to prescribe chemotherapy to 965 patients were reminded electronically to screen patients for hepatitis B. Only 88 patients in the study group had been previously screened for hepatitis B.
Prompted by the reminders, the doctors in the study achieved an 85.5% (825 of 965 patients) screening rate in compliance with medical recommendations.
Unfortunately, many doctors failed to take the next step and prescribe antivirals to stop hepatitis B reactivation in these patients. Only 45.5% of patients whose screening uncovered prior or current hepatitis B infections were prescribed antivirals during chemotherapy.
“The rates of antiviral prophylaxis were lower for doctors treating lung, breast and colorectal cancers than for those treating hematological (blood) malignancies,” the researchers reported.
Only 1.6% of antiviral-treated patients experienced reactivation of their hepatitis B, compared to 15.1% of patients who were not treated with antivirals and suffered HBV reactivation during their cancer treatment.
“By using this reminder system, the overall screening rate for HBsAg was satisfactory, whereas the antiviral prophylaxis was inadequate in patients with solid tumors due to the varying compliance of the attending doctors,” researchers wrote. “Further strategies to improve both screening and prophylaxis are needed to minimize HBV-related events during … chemotherapy.”
Source: www.ncbi.nlm.nih.gov/pubmed/
25658926
Study Finds Getting Frequent Cancer Screenings Saves Lives
Getting regular ultrasound screenings for liver cancer–at least every six to 12 months–increases survival among liver cancer patients, including those with hepatitis B, according to a study published in the February issue of the journal Gut.
Current medical guidelines recommend regular liver cancer screening in hepatitis B patients, especially those with indications of liver damage, fibrosis and cirrhosis (severe scarring.) However, it has not been clear how beneficial the more frequent screenings are to treatment and survival. A new study shows frequent screenings clearly result in longer survival.
Taiwanese researchers followed 52,823 patients newly-diagnosed with liver cancer between 2002 and 2007. They determined how recently the patients had received ultrasound screenings, and what impact the timing of the screenings had on their survival and quality of treatment.
The percentage receiving cancer treatment was slightly better with more frequent screenings.
24.3% of patients who had ultrasounds in the past six months received treatment
Compared to only 18.3% of patients who had never been screened.
Survival increased among patients with frequent ultrasound screenings over the five-year study period. When compared to patients who had been screened within the past six months, the five-year death rate was:
11% higher in patients who had ultrasounds 12 months ago
23% higher in patients who had ultrasounds 24 months previously
31% higher in patients who were screened 36 months ago,
And 47% higher in patients who had never been screened.
“…The associations between shorter screening intervals and better survival were observed in nearly all subgroups, especially in younger patients, patients without diabetes and patients with hepatitis B infection,” they wrote.
Source: http://www.ncbi.nlm.nih.gov/pubmed
/25670811
Use of Radio Waves to Destroy Small Liver Tumors as Effective as Surgery
Radiofrequency ablation (RFA), which uses carefully-targeted radiofrequency waves to increase the temperature inside cancerous tumors in order to destroy them, appears to be as effective as surgery in treating hepatitis B patients with small liver tumors, according to a 10-year study.
Chinese researchers, reporting in the March issue of the journal Medical Oncology, followed 837 hepatitis B patients who had small liver cancer nodules, measuring 3 cm or smaller, removed using RFA. This medical procedure is less invasive than surgery and can be performed in outpatient settings.
The researchers reported the 1-, 3-, 5- and 10-year survival rates of their patients were 91%, 71%, 54%, and 33% respectively.
The 1-, 3-, 5-, and 10-year liver cancer-free survival rates were 74%, 44%, 30% and 15 % respectively.
Lower alpha fetoprotein levels and fewer nodules increased the patients' survival rates.
“RFA achieved comparable long-term overall survival rates to those of surgical resection (removal) with fewer major complications and could therefore be considered as an alternative option for curative treatment of patients with small liver cancer,” the researchers reported.
Source: http://www.ncbi.nlm.nih.gov/pubmed
/25698535
Interferon Increases Thyroid Disease in Hepatitis B and C Patients
Hepatitis B and C patients treated with conventional and pegylated interferon had high rates of thyroid problems, according to a study published in a Czech medical journal (PMID: 25702290).
Researchers followed 256 patients infected with the hepatitis C virus (HCV) and 48 hepatitis B patients who were treated with conventional and pegylated interferon. Over the course of the study, which took place between 1992 and 2013, thyroid dysfunction was found in 25% of the patients, including 68 (26.5%) with hepatitis C and seven (14.5%) with hepatitis B.
Source: http://www.ncbi.nlm.nih.gov/pubmed
/25702290
Smoking Impairs Recovery from Hepatitis B and the Effectiveness of Immunization
Smoking appears to hamper the effectiveness of hepatitis B immunization as well as increase the risk of developing a chronic infection in those who are infected by HBV, according to a report by researchers in Bangladesh, published in the February issue of the journal Viral Immunology.
Hepatitis B vaccination works by injecting only a piece of the virus–the hepatitis B surface antigen–in order to promote development of protective surface antibodies. When researchers compared the levels of surface antibodies in vaccinated smokers to those in non-smokers, they found smokers’ rates of protective levels of antibodies were almost nine times lower than among vaccinated non-smokers.
Among people who have been infected by the virus, it appears that non-smokers are more likely to clear the infection and develop surface antibodies on their own than are smokers.
The researchers identified 132 people who had been infected, evidenced by the presence of the hepatitis B core antibody. Only 44 (33.3%) of these infected patients cleared the infection and developed surface antibodies. The researchers found that HBV-infected cigarette smokers had much lower rates of clearing the infection than non-smokers.
“These data suggest that surface antibody development, either naturally or after vaccination, is significantly lower among smokers,” they wrote. The study underscores the importance of measuring surface antibody levels in smokers following immunization to see if adequate protective levels of antibodies have developed, and whether a booster vaccine is required to confer protection against the infection.
Source: http://www.ncbi.nlm.nih.gov/pubmed
/25714135
Hepatitis B Immunization Coverage Declined 2.1% in 2013
The percentage of U.S. adults age 19 and older who have been immunized against hepatitis B dropped to 25% in 2013, a decline of 2.1% from 2012 levels, according to a Feb. 6, 2015, report by the U.S.Centers for Disease Control and Prevention published in Morbidity and Mortality Weekly Report.
The study found that racial disparities continued to persist, with African-Americans and Hispanics reporting lower hepatitis B vaccinations than whites.
CDC officials track vaccine coverage annually in order to identify weaknesses in the public’s protection against infectious diseases. Immunization coverage depends heavily on health care providers to recommend immunizations based on their patients’ age and health risks.
CDC researchers reported that hepatitis B vaccination coverage overall was 25% for all adults age 19 and older, 32.6% for adults aged 19-49 and 16.1% in adults over age 50.
The CDC recommends all adults at risk of HBV infection due to sexual practices, contact with infected family members, and a family history of immigration from regions with high HBV infection rates (such as Asia and Africa). Adults 60 and older with diabetes should also be vaccinated.
According to the report, vaccination among adults (aged 19-49) was lower for African-Americans (30.5%) and Hispanics (23.7%) compared to whites (35.2%). Even among health care providers, for whom immunization is mandated, coverage rates were lower for Hispanics (54%) than whites (62.9%). These findings suggest that doctors may be dropping the ball when it comes to making sure patients receive the immunizations they need. “Routine assessment of adult patient vaccination needs, recommendations and offer of needed vaccinations for adults should be incorporated into routine clinical care of adults,” the CDC researchers wrote.
Source: www.cdc.gov/mmwr/preview/mmwrhtml
/mm6404a6.htm
|
|
发表于 2015-3-2 15:37
