Coffee intake and the incident risk of cognitive disorders: A dose-response meta-analysis of nine prospective cohort studies

No clue what a “J-shaped” association is or what non-significant heterogeneity they are referring to is. Send your doctor after the answers. Coffee has way too many benefits for me to stop using it.
Ask your doctor very specifically; How many cups of coffee are needed to stop your 33% dementia chance post-stroke from an Australian study?
Do not take 'I don't know for an answer', tell them to come back with documented research to back up their answer. If we don't start demanding our doctors actually know what the hell they are doing in stroke rehab they will never change. 
I guess they totally miss the other research that says this:

Coffee May Lower Your Risk of Dementia 

  and this:

Drinking Coffee Can Lower Alzheimer's Risk By 20%, All It Takes Is 3 Cups A Day

And the supposed negative research here:

Coffee intake and the incident risk of cognitive disorders: A dose-response meta-analysis of nine prospective cohort studies

Lei Wu

,

Dali Sun

,

Yao He

DOI: http://dx.doi.org/10.1016/j.clnu.2016.05.015

Article Info

• Abstract

Summary

Background & aims

Previous epidemiological studies have provided inconsistent conclusions on the impact of coffee consumption in the developing of cognitive disorders. However, no previous meta-analysis has pooled the evidence from the prospective cohort studies to assess the influence of coffee drinking and its potential dose-response patterns on the risk of developing cognitive disorders specifically.

Methods

Two databases (PubMed and Embase) were searched for evidence of cohort studies from inception to February 2016. We used a generic inverse-variance method with a random-effects model to pool the fully adjusted relative risks (RRs) and the corresponding 95% confidence intervals (CIs). In the dose-response analyses, a generalized least-squares trend estimation model was applied to computing the study-specific slopes.

Results

Nine prospective cohort studies involving 34,282 participants were included in our study. The duration of follow-up years ranged from 1.3 to 28. Compared with <1 cup, daily drinking of 1-2 cups of coffee was inversely linked with the occurrence of cognitive disorders (i.e., Alzheimer’s disease, dementia, cognitive decline, and cognitive impairment), and the pooled RR (95% CI) was 0.82 (0.71, 0.94) with evidence of non-significant heterogeneity (I²=25%). Non-significant differences were presented for the association between coffee consumption (>3 vs. <1 cup/d) and incident cognitive disorders. The dose-response analysis showed a “J-shaped” curve relationship of the risk of developing cognitive disorders with coffee consumption.

Conclusions

A “J-shaped” association was presented between coffee intake and incident cognitive disorders, with the lowest risk of incident cognitive disorders at a daily consumption level of 1-2 cups of coffee.