SUMMARY
Background: Understanding the association between water
consumption and mortality is important for guiding consumers and
prioritizing dietary guidelines to reduce the risk. Therefore, in the
current study, we conducted a systematic review and dose-response
meta-analysis of prospective cohort studies to summarize the association
between total water and drinking intake and risk of mortality from all
causes and CVD.
Method: A comprehensive search was performed on PubMed/Medline,
Scopus, and ISI Web of Science up to February 2020. The random effects
model was used to calculate pooled effect size (EFs) and 95% confidence
interval.
Result: Seven prospective cohort studies with a total of 116816
reporting 14754 cases of all-cause mortality and 7611 of CVD mortality,
were included in the present meta-analysis. No significant association
was found between drinking water intake and all-cause mortality (EFs:
0.82; 95% CI: 0.63-1.08, P=0.65) and CVD mortality (EFs: 0.82; 95% CI:
0.63-1.08, P= 0.16). Total water intake was not associated with
all-cause mortality (EFs: 0.95; 95% CI: 0.83-1.09, P=0.47). However,
indicating a significant inverse association between total water intake
and risk of CVD mortality (EFs: 0.84; 95% CI: 0.77-0.93,
P<0.001). Linear dose-response meta-analysis revealed a
significant inverse association between total water intake and all-cause
mortality by an additional one cup per day (Pooled ES: 0.98; 95% CI:
0.97-0.99, P= 0.001). Furthermore, each additional cup of total water
intake per day was associated with a 3% lower risk of death from CVD
(Pooled ES: 0.97; 95% CI: 0.96-0.98, P<0.001).
Conclusion: High consumption of total water is associated with
a lower risk of CVD mortality. However total water intake was not
associated with an increased risk of all-cause mortality.
keywords: drinking water, total water, all-cause mortality, CVD
mortality