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Showing posts from December, 2017

Microbiome and colitis: a new approach

one issue in current microbiome research is that there are often associations between certain microbial species found in the gut microbiome and certain disease or health states, but the direct cause/effect link is not clear. these researchers, looking at a colitis model in mice, derived an improved approach in assessing causality (see   doi:10.1038/nature25019 ​). Background: --they studied gnotobiotic mice (ie, mice with known gut microbiomes), some mice with mouse microbiota (MMb) and some with human microbiota (HMb); and also some specific-pathogen free (SPF) mice --these mice were exposed to DSS (dextran sodium sulfate), known to cause colitis in mice     ​--in MMb mice, the colitis was clinically associated with severe weight loss and 100% mortality     ​--in HMb mice, as well as SPF mice, they lose less weight and rarely die; but the degree of microscopic colonic inflam...

Global deaths from influenza

​ a new analysis in the Lancet found that the global influenza-related mortality is likely much higher than previously suggested (see doi.org/10.1016/S0140-6736(17)33293-2  ). Details: --they assessed country-specific excess mortality rates (EMR) related to influenza for countries having vital death records and influenza surveillance data --they then extrapolated data to countries without such records by dividing countries into 3 analytic divisions (stratified by country-specific global health estimates of respiratory infection rates) for 3 age-groups (<65 yo, 65-74 yo, >75 yo), using the WHO Global Health Estimate respiratory infection mortality rates, attributing estimates of influenza-associated mortality from countries with similar mortality risk Results: --EMR-contributing countries (33 of them) represented 57% of the global population (4.15 billion of 7.34 billion in the world) --the 33 countries with EMR data: 2 from sub-S...

Hepatitis B screening recommendations

​​The American College of Physicians and the CDC recently published their "best practice advice" for Hepatitis B vaccination, screening and linkage to care ( see  DOI:  10.7326/M17-1106 ​, or  http://annals.org/aim/fullarticle/2664089/hepatitis-b-vaccination-screening-linkage-care-best-practice-advice-from  ). Details: --Vaccination:     --it works, with about 90% effectiveness in healthy adults <40 yo. Since implementation of universal vaccination of newborns, the number of acute  hep B virus (HBV)  infec tions   in adults ​ has  decreased  from 9.6 per 100,000  people  in 1982 to 1.1 per 100,000 in 2015     --Recommendations are to vaccinate all adults at risk: sexual and household contacts of HBsAg-positive persons, sexually active people not in mutually monogamous relationships [often hard to know for sure....], people seeking evaluation for STIs, MSM, recent o...

Men: the weaker sex

a really, really important article was just published in the holiday edition of the BMJ, exploring the science behind "man flu"​​, which the Oxford English dictionary defines as: "a cold or similar minor ailment as experienced by a man who is regarded as exaggerating the severity of the symptoms" (see  https://en.oxforddictionaries.com/definition/man_flu ). this BMJ article suggests that it is not simply that men are wimpier, but they actually may have a weaker immune system, and that there may be an evolutionary basis for this (see   http://www.bmj.com/content/359/bmj.j5560  ,  or  doi : 10.1136/bmj.j5560 ). my minimally detailed search has suggested that this "man flu" thing is actually sort of real and not a joke (though not having heard of it before, i must admit that i did suspect otherwise, and was especially doubtful that there would be an Oxford English dictionary definition of it....). Details: --female mice have greater...

Metformin decreases dementia risk

 A retrospective analysis of veterans found that metformin vs sulfonylureas was associated with a lower risk of subsequent dementia (see   doi .​org/​10.​1212/​WNL.​0000000000004586  ). Details: --US veterans >65  yo  with type 2 diabetes who were new users of metformin or a sulfonylurea, with no baseline dementia and without diabetes complications, were accessed through the VA clinical and administrative databases, with linkage to Medicare to help capture comorbidities --mean age 73.5 years, mean A1c=6.8%. average follow-up 5 years; 10% black/87% white, 40% overweight/50% obese, --more on sulfonylureas were older, normal weight,  eGFR  <60, CAD, heart failure, atrial fibrillation,  PAD, TIA/stroke, cancer; and more on metformin had A1c <7%, hyperlipidemia, substance abuse --analysis was done by propensity match scoring to decrease risk of confounding (this is a statistical method to at...

New oral contraceptives and breast cancer

a recent article, highly publicized in the press, found a significant risk of breast cancer in women on contemporary (ie lower dose) hormonal contraception (see DOI: 10.1056/NEJMoa1700732). study was industry-supported. Details: --nation-wide prospective cohort study of all women in Denmark between 15-49 yo, who had not had cancer or venous thromboembolism. --1.8 million  women followed average of 10.8 years --fully adjusted models (below) included: level of education, parity, polycystic ovary syndrome, endometriosis, family history of breast/ovarian cancer; and BMI, smoking status, and age at first delivery when women were parous (these last 3 were available only in women who had a kid) Results: --11,517 cases of breast cancer occurred overall --relative risk of breast cancer:     --current or recent hormonal contraception users: 20% increase, RR 1.20 (1.14-1.26)        ...