H Pylori eradication and reduced risk of gastric cancer

A recent systematic review/meta-analysis looked at the effects of H pylori eradication and the incidence of gastric cancer (see hpylori rx and dec gastric ca gastro2016​ in dropbox, or doi.org/10.1053/j.gastro.2016.01.028). ​
details:

--background:
    --there are >720,000 deaths/yr from gastric cancer worldwide
    --H pylori infection is the most important etiologic factor, infecting approximately 50% of the global population, and estimated to cause 78% of gastric cancers
    ​--mechanistically, H pylori causes chronic gastric inflammation, leading to precancerous changes of atrophic gastritis, and also to gastric mucosal genetic instability through decreased acid secretion, "which can promote the growth of gastric microbiome that processes dietary components into carcinogens"
--​24 studies, with a total of 715 incident gastric cancers among a total of 48,064 patients and 340,255 person-years of followup. almost all of the studies were from Korea, China and Japan. 14 studies were in asymptomatic individuals and 10 were in those who had undergone endoscopic resection of early gastric cancers
--results: 
    --253 gastric cancers developed in 20,484 individuals who received H pylori treatment and 462 of 27,580 who did not get the treatment
    ​--baseline incidence of gastric cancer in those not getting treatment varied widely from 34.3 to 10,265.4/100K person-years
    ​--those with H pylori eradication had 46% lower incidence of gastric cancer (pooled incidence rate ratio of 0.54 (0.46-0.65), with little heterogeneity among the studies.
    --eradication of H pylori in asymptomatic individuals still had significant benefit (pooled incidence rate ratio of 0.62 (0.49-0.79)
    --the benefit of eradication in the group with endoscopic gastric cancer resection was even better, with pooled incidence rate ratio of 0.46 (0.35-0.60)    
    ​--the benefit of eradication was (not surprisingly) more significant in areas with a high baseline rate of gastric cancer (if 2,970 to 10,256.4/100K person-years​, then pooled incidence rate ratios were 0.45); decreased in those with intermediate rates (314.3-2914.2/100K person-years,  pooled incidence rate ratios were 0.49; and was not significant if low rates (34.2-253.6/100K person-years, ​ pooled incidence rate ratios were 0.80)

so,

--in another study by the current authors, a population-based mass eradication program on Matsu Island of Taiwan, found that H pylori eradication reduced atrophic gastritis in patients with premalignant lesions and reduced cancer incidence by 25% (from 40.3 to 30.4/100K person-years)
--unlike some other studies, the systematic review above found that even treating those with early gastric cancers had some benefit
--i am a little concerned about generalizing these results to other areas of the world, since these studies are mostly from Asia, and more developed regions of Asia at that. for example, in many countries with high rates of H pylori, there are not the epidemiologic data on the real incidence/prevalence of either H pylori or gastric cancer. i am also not sure that the strains/variants of H pylori are the same in different regions, or even have the same association with gastric cancer. that being said, i spoke with a public health-minded physician from Cape Verde, an area where many of our patients come from, and he was under the impression that there was a lot of gastric cancer there. but there are no concrete data, and the prevalence could well vary from island to island. i did decide to test and treat my patients after i found a few cases of gastric cancer in Capeverdean patients (long live anecdotes ....​)
--I have sent out many blogs on H pylori in the past, since it is  such a big issue in much of the world and so prevalent in many of the immigrant communities in the US. see:  

http://gmodestmedblogs.blogspot.com/2014/05/gastric-cancer-screeningprevention-h.html which comments on endoscopic screening for high risk patients (again, in Korea, Japan, and China). 

http://gmodestmedblogs.blogspot.com/search/label/H%20Pylori for an array of articles on H pylori regimens (including salvage regimens) and one on the increased risk of GI bleeding in patients with H pylori and taking NSAIDs

Comments

Post a Comment

if you would like to receive the near-daily emails regularly, please email me at gmodest@uphams.org

Popular posts from this blog

cystatin c: better predictor of bad outcomes than creatinine

  another article found significant discordance between creatinine and cystatin C in assessing renal function,  finding that the latter correlated most strongly with both renal and non-renal adverse clinical outcomes (see   ckd cystatin c better than creat AJKD2023  in  dropbox or doi: 10.1053/ j.ajkd.2023.04.002)   Details: -- 158,601 adults who were in the Stockholm Creatinine Measurements (SCREAM) project and had testing of creatinine and cystatin C on the same day during a healthcare encounter, from 2010-2018     -- >400,000 outpatient tests were done for both creatinine and cystatin C levels -- mean age 62, 48% female -- mean eGFR by creatinine (   eGFR cr ) 80; mean eGFR by cystatin C ( eGFR cys  ) 73 -- mean stage of renal insufficiency: 39%  eGFR cr   90+; 38%  eGFR cr  60-89; 12%  eGFR cr  45-59; 7.1%  eGFR cr  30-44; 3.2%  eGFR cr  15-29, 0.7%  eGFR cr ...
Read more

diabetes DPP-4 inhibitors and the risk of heart failure

the FDA just came out with a safety alert about 2 DPP-4 inhibitors and the increased risk of heart failure (released 04/05/2016)(see  http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm494252.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery ​ ). details: --saxagliptin and alogliptin were singled out because of 2 clinical trials in diabetic patients with heart disease. in each trial more patients taking these meds were hospitalized for heart failure vs those on placebo     --in the saxagliptin trial: 3.5% were hospitalized for heart failure (vs 2.8% on placebo). risk factors included prior heart failure or kidney disease     --in the alogliptin trial: 3.9% were hospitalized for heart failure (vs 3.3% on placebo) --recommendation by the FDA:     -- we should consider stopping these drugs if the patient develops heart failure ...
Read more

UPDATE: ASCVD risk factor critique

I decided to do an extensive update of my prior ASCVD (atherosclerotic cardiovascular disease) risk analysis and critique of risk calculators, with much more information about the “non-traditional” risk factors. I felt that there should be more data/clarification, since I think we are really undertreating/not preventing the most common cause of death by relying on the current ASCVD risk calculators   -- Cardiovascular risk models:      -- many of us rely on the various cardiovascular risk models to determine the appropriate approach to patients, and these are often integrated into the electronic medical records      -- these risk models have several very important limitations:          -- they are typically based on community data, eg from the Framingham study etc. But, in clinical practice, we are dealing with the individual and not the community:          ...
Read more