Meta-analysis of modifiable risk factors for AD

Alzheimer's, cardiovascular, and other chronic diseases; biomarkers, lifestyle, supplements, drugs, and health care.
Silverlining
Senior Contributor
Senior Contributor
Posts: 366
Joined: Wed Oct 30, 2013 4:14 am

Meta-analysis of modifiable risk factors for AD

Post by Silverlining »

Meta-analysis of modifiable risk factors for Alzheimer's disease - August 20, 2015

http://jnnp.bmj.com/content/early/2015/ ... 015-310548

"Abstract

Background The aetiology of Alzheimer's disease (AD) is believed to involve environmental exposure and genetic susceptibility. The aim of our present systematic review and meta-analysis was to roundly evaluate the association between AD and its modifiable risk factors.

Methods We systematically searched PubMed and the Cochrane Database of Systematic Reviews from inception to July 2014, and the references of retrieved relevant articles. We included prospective cohort studies and retrospective case–control studies.

Results 16 906 articles were identified of which 323 with 93 factors met the inclusion criteria for meta-analysis. Among factors with relatively strong evidence (pooled population >5000) in our meta-analysis, we found grade I evidence for 4 medical exposures (oestrogen, statin, antihypertensive medications and non-steroidal anti-inflammatory drugs therapy) as well as 4 dietary exposures (folate, vitamin E/C and coffee) as protective factors of AD. We found grade I evidence showing that one biochemical exposure (hyperhomocysteine) and one psychological condition (depression) significantly increase risk of developing AD. We also found grade I evidence indicative of complex roles of pre-existing disease (frailty, carotid atherosclerosis, hypertension, low diastolic blood pressure, type 2 diabetes mellitus (Asian population) increasing risk whereas history of arthritis, heart disease, metabolic syndrome and cancer decreasing risk) and lifestyle (low education, high body mass index (BMI) in mid-life and low BMI increasing the risk whereas cognitive activity, current smoking (Western population), light-to-moderate drinking, stress, high BMI in late-life decreasing the risk) in influencing AD risk. We identified no evidence suggestive of significant association with occupational exposures.

Conclusions Effective interventions in diet, medications, biochemical exposures, psychological condition, pre-existing disease and lifestyle may decrease new incidence of AD."


The new one here for me is the hypotension/diastolic component. My diastolic typically runs from mid 40's to high 50's. I plan to look into this further, although other than taking BP elevation medications, I'm not sure how to get that number up. I already eat a lot of salt.
User avatar
Stavia
Contributor
Contributor
Posts: 5255
Joined: Tue Apr 29, 2014 6:47 pm
Location: Middle Earth

Re: Meta-analysis of modifiable risk factors for AD

Post by Stavia »

Statin?
User avatar
Stavia
Contributor
Contributor
Posts: 5255
Joined: Tue Apr 29, 2014 6:47 pm
Location: Middle Earth

Re: Meta-analysis of modifiable risk factors for AD

Post by Stavia »

Smoking????
User avatar
Julie G
Mod
Mod
Posts: 9187
Joined: Sat Oct 26, 2013 6:36 pm

Re: Meta-analysis of modifiable risk factors for AD

Post by Julie G »

How about drinking, stress, and high BMI in late life? Headspinning :shock: The low BMI as a risk factor scares me...
Wondering
Contributor
Contributor
Posts: 95
Joined: Thu Aug 06, 2015 12:20 am

Re: Meta-analysis of modifiable risk factors for AD

Post by Wondering »

And, since I had cancer, my AD risk is lower? :?

Head-spinning, for sure!

(Of course, there's nothing in the Abstract about APOE status, which we all know can change results pretty dramatically...)
E3/E4, both parents had LOAD
User avatar
Stavia
Contributor
Contributor
Posts: 5255
Joined: Tue Apr 29, 2014 6:47 pm
Location: Middle Earth

Re: Meta-analysis of modifiable risk factors for AD

Post by Stavia »

Lies, damned lies and statistics
Jean
Contributor
Contributor
Posts: 80
Joined: Sun Mar 22, 2015 2:22 pm
Location: Colorado, Front Range

Re: Meta-analysis of modifiable risk factors for AD

Post by Jean »

Amen Stavia :!:

The BMI thing is especially aggravating because it implies - forget the exercise, eat to get that BMI up if you're old, smoke so you get cancer first. Its disconcerting, but if there is any truth to that study, its telling me each one of us may have a bit of a different path to staying healthy. Its not the same prescription for everyone. I certainly hope for more commonalities, but not the ones stated in that study! :shock:
User avatar
jenniferthequeen
Contributor
Contributor
Posts: 23
Joined: Wed Jul 22, 2015 5:38 am

Re: Meta-analysis of modifiable risk factors for AD

Post by jenniferthequeen »

Yeah... I don't think it's time to get bombed and then stampede the All You Can Eat diner.


Sent from my iPad using Tapatalk
User avatar
Gilgamesh
Contributor
Contributor
Posts: 1711
Joined: Sat Oct 26, 2013 11:31 am
Location: Northeast US mostly
Contact:

Re: Meta-analysis of modifiable risk factors for AD

Post by Gilgamesh »

Juliegee wrote:How about drinking, stress, and high BMI in late life? Headspinning :shock: The low BMI as a risk factor scares me...
Damn lies, that last! Statistics and magic wands! No, seriously: all experienced, good researchers know that you can't control for things that make you both sick and thin. So people with Crohn's or colitis or celiac disease or A or B or C or... (most of which are often undiagnosed and thus not controlled for) lose weight and get AD. No surprise there. It's not the weight loss, it's the Crohn's or A or B or C that's causing the decline in health, which, in turn, increases the risk for AD. Okinawans are scrawny as hell, but live really long lives. And the rodent studies are clear on this when it comes to dementia prevention, and even the primate studies (where the lifespan effect was small, but the CR'd monkeys had almost no measurable brain atrophy).

But starting CR later in life is tricky, to be sure! One must ease into it. The initial adult-onset CR studies failed because the researchers dropped the energy-intake of the rodents (at human equiv. ages of 50-70 or so) all at once by 30+%, and weren't careful about ensuring sufficient micronutrient intake.

And we need a good test of protein status or nitrogen balance. That I do worry about with CR in older age. Stavia, is there a reliable blood test that says something about nit. balance? I'm getting 70-80 g protein / day now on avg., nice firm BMs, so no reason to believe I'm not absorbing it as well as the next guy, exercising pretty lightly (these days) -- pulse up to 90-110 only -- 30-50 mins./day on avg. Minor weight-lifting (10-15 min. / day on avg.).

But main point, again: lies, lies, lies! In the US, having blue eyes is correlated with longer life. That doesn't mean you should try to get some crazy gene therapy or something to change your eye color (simply) because you have brown eyes and live in the US.
marthaNH
Contributor
Contributor
Posts: 554
Joined: Thu Dec 18, 2014 12:47 pm

Re: Meta-analysis of modifiable risk factors for AD

Post by marthaNH »

Thank you, Gilgamesh. Since I've been reading this forum for six or eight months now, some of what you say is familiar to me, and I know not to freak out at something that sounds non-sensical, but it still really helps to read a clear explanation like what you posted above.

Good luck with everything this week.
Post Reply