PLOS Medicine: Coffee, tea, coffee + tea can all reduce the risk of stroke and dementia!

With the increasing trend of population aging, dementia has become a health problem of increasing concern worldwide, and has brought heavy economic and social burdens
.

In 2019, more than 50 million people worldwide suffer from dementia
.

It is estimated that by 2050, this number will increase to 152 million
.

In view of the limited therapeutic value of the drugs currently used to treat dementia, determining the preventable risk factors for dementia is a top priority
.

Stroke accounts for 10% of global deaths and is the main cause of all disability-adjusted life years
.

Although the global age-standardized incidence and mortality of stroke have declined in the past 20 years, the absolute number of stroke cases and deaths has increased
.

Stroke and dementia bring risks to each other and share some of the same, modifiable risks and protective factors
.

A population-based longitudinal study found that stroke and dementia share approximately 60% of the risk and protective factors
.

In principle, 90% of strokes and 35% of dementias are estimated to be preventable
.

Coffee and tea are among the most widely consumed beverages in the world
.

Coffee contains caffeine, which is a rich source of antioxidants and biologically active compounds
.

According to reports, tea containing caffeine, catechin polyphenols and flavonoids has neuroprotective effects, such as anti-oxidative stress, anti-inflammatory, inhibition of amyloid-beta polymerization and anti-apoptosis
.

Coffee consumption is closely related to tea consumption
.

A prospective cohort study showed that approximately 70% of participants drank coffee and tea at the same time
.

Epidemiological and clinical studies have shown that coffee and tea are beneficial to the prevention of dementia, respectively.
However, little is known about the association between the combination of coffee and tea and the risk of dementia
.

Therefore, this study aims to explore the association between coffee and tea, which may be multiplicative or additive, and the risk of stroke and dementia
.

This prospective cohort study included 365,682 participants (50 to 74 years old) from the British Biobank
.

Participants participated in this study from 2006 to 2010 and have been tracking it until 2020
.

Among 365,682 participants, the average age was 60.
4±5.
1 years, and 167,060 (45.
7%) were men
.

Among 365,682 participants, 59,558 (16.
29%) reported drinking 0.
5 to 1 cup of coffee and ≥4 cups of tea per day, accounting for the largest proportion; followed by 50015 (13.
68%), reporting drinking 0 cups of coffee and ≥4 cups per day Tea
.

In addition, 44868 (12.
27%) participants reported that they drank 2 to 3 cups of coffee and 2 to 3 cups of tea a day
.

Table 1 shows the baseline characteristics of the participants
.

Compared with participants who did not drink coffee, coffee drinkers were more likely to be men, whites, former smokers, current drinkers, college degrees, and high-income earners
.

Similarly, compared with non-tea drinkers, tea drinkers are more likely to be men, never smokers, and current drinkers, have a college degree, and are more physically active
.

In addition, compared with participants who drank neither coffee nor tea, participants who drank both beverages were more likely to be elderly, male, white, former smoker, current drinker, have a college degree, and The income is very high
.

Coffee intake (cup/day) is related to tea intake (r = +0.
337, P <0.
001)
.

Drinking coffee and tea are related to gender, age, race, qualifications, income, body mass index, physical activity, alcohol status, smoking status, consumption of sugar-sweetened beverages, low-density lipoprotein, cancer, diabetes, and CAD, but are related to HDL Irrelevant
.

The median follow-up for new onsets was 11.
35 years, 10053 participants (2.
8%) had strokes (5630 ischemic strokes and 1815 hemorrhagic strokes), and 5079 participants (1.
4%) had dementia (2128 people have Alzheimer's disease and 1223 people have vascular dementia)
.

In the unadjusted and multi-adjusted models (Figure 1), the combination of coffee and tea is associated with stroke, dementia, and post-stroke dementia
.

In the multi-adjustment model, the association of coffee and tea with stroke and dementia is non-linear (non-linear P<0.
001), coffee intake is 2 to 3 cups/day or tea intake is 3 to 5 cups/day , Or coffee and tea intake of 4 to 6 cups/day is related to the minimum risk ratio (HR) for stroke and dementia
.

In addition, the combination of tea and coffee is associated with a lower risk of post-stroke dementia: consuming 3 to 6 cups of coffee and tea a day has the lowest risk of dementia after stroke (HR, 0.
52, 95% CI, 0.
32 to 0.
83: P = 0.
007)
.

In order to analyze the association between coffee and tea intake and new disease outcomes, we defined coffee and tea intake into the following categories: 0, 0.
5 to 1, 2 to 3, and ≥ 4 cups/day
.

We investigated the association between the intake of each type of coffee and tea and stroke and its subtypes (Figure 2)
.

In the unadjusted Cox model, coffee and tea intake was associated with a lower risk of stroke
.

After multivariate adjustments, coffee intake was associated with a reduced risk of stroke
.

Compared with non-coffee drinkers, the HR for coffee intake of 0.
5 to 1, 2 to 3 and ≥4 cups/day was 0.
90 (95% CI, 0.
85-0.
95: P <0.
001) and 0.
88 (95% CI) , 0.
84-0.
94: P <0.
001) and 0.
92 (95% CI, 0.
86-0.
98: P = 0.
009)
.

Similarly, after adjusting for confounding factors, tea intake was associated with a reduced risk of stroke
.

The HR of 0.
5 to 1, 2 to 3, and ≥4 cups/day were 0.
97 (95% CI, 0.
89 -1.
04, P = 0.
386), 0.
84 (95% CI, 0.
79 -0.
90; P <0.
001) and 0.
84 (95% CI, 0.
79 -0.
90; P <0.
001), respectively.
% CI, 0.
79-0.
90: P <0.
001)
.

In addition, coffee and tea are both associated with a low risk of ischemic stroke, but not associated with hemorrhagic stroke (P>0.
05)
.

In addition, we examined the joint association between coffee and tea intake and stroke and its subtypes (Figure 2)
.

In the unadjusted and multi-adjusted models, the combination of coffee and tea is associated with a lower risk of stroke and ischemic stroke
.

In the multi-adjustment model, compared with the group without tea and coffee, the HRs for stroke and ischemic stroke of drinking 2 to 3 cups of coffee and 2 to 3 cups of tea per day were 0.
68 (95% CI, 0.
59-0.
79), respectively.
: P <0.
001) and 0.
62 (95% CI, 0.
51 -0.
75: P <0.
001) 
.

However, coffee and tea were not found to be associated with hemorrhagic stroke
.

There was a statistical interaction between tea and coffee intake during stroke (P <0.
001)
.

This study subsequently assessed the association of each type of coffee and tea with dementia and its subtypes (Figure 3)
.

In the unadjusted Cox model, coffee, tea intake and their combination were associated with reducing the risk of dementia and vascular dementia, but not with Alzheimer's disease
.

After adjusting for mixed factors, coffee intake was associated with reducing the risk of dementia and vascular dementia, but not with Alzheimer's disease
.

Similarly, tea intake is associated with reducing the risk of dementia and vascular dementia, but not with Alzheimer's disease
.

Next, the joint association between coffee and tea intake and dementia and its subtypes was evaluated
.

We found that drinking 0.
5 to 1 cup of coffee and ≥4 cups of tea a day has the lowest risk of dementia
.

Compared with people who do not drink coffee and tea, the HR of drinking 0.
5 to 1 cup of coffee and ≥4 cups of tea per day is 0.
70 (95% CI, 0.
58-0.
86: P <0.
001), and drinking 2 to 3 cups of coffee and 2 per day The HR to 3 cups of tea was 0.
72 (95% CI, 0.
59-0.
89: P = 0.
002)
.

There was a statistical interaction between tea and coffee intake and dementia and vascular dementia (P = 0.
0127)
.

In addition, the combination of coffee and tea intake is associated with a lower risk of vascular dementia, but not with Alzheimer's disease
.

In addition, we evaluated the HR of those participants who drank coffee and tea at the same time and those who only drank coffee or tea
.

After adjusting for confounding factors, compared with participants who only drank coffee or tea, participants who drank coffee and tea at the same time had stroke (HR 0.
89: 95% CI, 0.
86 to 0.
93: P <0.
001), and ischemic stroke (HR 0.
89) : 95% CI, 0.
84 to 0.
94: P <0.
001), dementia (HR, 0.
92: 95% CI, 0.
87 to 0.
98: P = 0.
001) and vascular dementia (HR, 0.
82; 95% CI, 0.
72 to 0.
92; P <0.
001) have lower risks
.

We further studied the association of coffee and tea with dementia and its subtypes in stroke participants
.

Of the 13,352 stroke patients, 646 participants (4.
8%) developed dementia (119 Alzheimer’s and 315 vascular dementia) during a median follow-up of 7.
07 years
.

In the unadjusted Cox model, coffee and a combination of coffee and tea are associated with lowering the risk of dementia
.

After multivariate adjustment, participants who drank 2 to 3 cups of coffee a day were associated with a lower risk of dementia compared with non-coffee drinkers (HR, 0.
80: 95% CI, 0.
64 to 0.
99, P = 0.
044)
.

Next, we evaluated the combination of coffee and tea intake and subtypes of dementia in stroke participants
.

We found that the combination of coffee and tea is associated with a lower risk of dementia after stroke
.

Compared with people who did not drink coffee and tea, people who drank 0.
5 to 1 cup of coffee and 2 to 3 cups of tea a day had a post-stroke dementia HR of 0.
50 (95% CI, 0.
31 to 0.
82: P = 0.
006) 
.

However, no link has been found between coffee and tea and Alzheimer's disease and vascular dementia
.

There was no interaction between tea and coffee intake and dementia and vascular dementia (P>0.
05)
.

We also assessed the correlation between coffee type and stroke and dementia
.

Among coffee drinkers, 160,741 (44.
0%), 63,363 (17.
3%), and 57,397 (15.
7%) drank instant coffee, ground coffee, and decaffeinated coffee, respectively
.

In the multi-adjusted Cox regression model, compared with instant coffee, ground coffee is not associated with stroke and its subtypes (HR, 0.
98; 95% CI, 0.
93 ~ 1.
04; P = 0.
619)
.

Compared with decaffeinated coffee, instant coffee is not associated with stroke and its subtypes (HR, 0.
95; 95% CI, 0.
90 ~ 1.
01; P = 0.
074), while ground coffee is associated with lower stroke (HR, 0.
90, 95% CI, 0.
84 to 0.
97; P = 0.
006) is associated with the risk of ischemic stroke (HR, 0.
90, 95% CI, 0.
82-1.
00; P = 0.
045)
.

For dementia, in the multi-adjusted Cox regression model, compared with instant coffee, ground coffee has a lower risk of dementia (HR, 0.
83; 95% CI, 0.
77-0.
89; P <0.
001), Alzheimer's disease (HR , 0.
77; 95% CI, 0.
69 ~ 0.
87; P <0.
001), vascular dementia (HR, 0.
82; 95% CI, 0.
70 ~ 0.
96; P = 0.
012) risk related
.

Compared with decaffeinated coffee, instant coffee is associated with lower dementia (HR 0.
85; 95% CI, 0.
79 ~ 0.
92; P <0.
001), Alzheimer's disease (HR, 0.
81; 95% CI, 0.
72 ~ 0.
91; P<0.
001), vascular dementia (HR, 0.
84; 95% CI, 0.
72 ~ 0.
99; P = 0.
036) is associated with risk; coffee powder is associated with a lower risk of dementia (HR, 0.
74; 95% CI, 0.
66 ~ 0.
82; P <0.
001), Alzheimer's disease (HR, 0.
67; 95% CI, 0.
57 ~ 0.
78; P<0.
001), vascular dementia (HR, 0.
74; 95% CI, 0.
59 ~ 0.
92; P = 0.
008 )
.

 In summary, this large prospective cohort study found that: (1) the individual and combined intake of tea and coffee are associated with lower risks of stroke, ischemic stroke, dementia and vascular dementia; (2) report Participants who drank 2 to 3 cups of coffee and 2 to 3 cups of tea a day had a 30% reduction in the risk of stroke and dementia; (3) The combination of coffee and tea seemed to be compared with drinking coffee or tea, respectively.
The risk is lower; (4) Coffee intake alone or in combination with tea is associated with a lower risk of dementia after stroke
.

In summary, the results of this study show that moderate consumption of coffee and tea, whether taken alone or in combination, is associated with a lower risk of stroke and dementia
.

 Reference: Yuan Zhang, et al.
Consumption of coffee and tea and risk of developing stroke, dementia, and poststroke dementia: A cohort study in the UK Biobank.
PLOS Medicine | https://doi.
org/10.
1371/journal.
pmed .
1003830 November 16, 2021 Written | LILYMED Editor | PP Click "Read the original text" below to download Metz Medical APP