Dietary acid load and mortality from all causes, CVD and cancer: results from the Golestan Cohort Study.

Given the limited studies and controversial results on association between dietary acid load and mortality from CVD and cancers, we aimed to investigate this association in a large population cohort study in Middle East, with a wide range of dietary acid load. The study was conducted on the platform of the Golestan Cohort Study (GCS), which enrolled 50 045 participants in 2004-2008. Dietary intake was assessed using a validated FFQ. Dietary potential renal acid load (PRAL) score was calculated from nutrient intake. Death and its causes were identified and confirmed by two or three physicians. Cox proportional hazards regression was used to estimate hazard ratio (HR) and 95 % CI for total and cause-specific mortalities. Then, the associations were modelled using restricted cubic splines. PRAL range was -57·36 to +53·81 mEq/d for men and -76·70 to +49·08 for women. During 555 142 person-years of follow-up, we documented 6830 deaths, including 3070 cardiovascular deaths, 1502 cancer deaths and 2258 deaths from other causes. For overall deaths, in final model after adjustment for confounders, participants in the first and fifth quintiles of PRAL had a higher risk of mortality compared with the second quintile of PRAL (HR: 1·08; 95 % CI1·01, 1·16 and HR: 1·07; 95 % CI 1·01, 1·15, respectively); Pfor trend < 0·05). Participants in the first and fifth quintiles of PRAL had a 12 % higher risk of CVD mortality compared with the Q2 of PRAL (HR: 1·12; 95 % CI 1·01-1·25 and HR: 1·12; 95 % CI 1·01, 1·26, respectively; Pfor trend < 0·05). We found that all-cause and CVD mortality rates were higher in the lowest and highest PRAL values, in an approximately U-shaped relation (P-values for the overall association and the non-linear association of energy-adjusted PRAL with total mortality were < 0·001 and < 0·001, and with CVD mortality were 0·008 and 0·003, respectively). Our results highlight unfavourable associations of high acidity and alkalinity of diet with the increased total and CVD mortality risk. It may be important to consider a balanced acid-base diet as a protective strategy to prevent pre-mature death, especially from CVD.

The Combined Effects of Healthy Lifestyle Behaviors on All-Cause Mortality: The Golestan Cohort Study.

BACKGROUND: Most studies that have evaluated the association between combined lifestyle factors and mortality outcomes have been conducted in populations of developed countries. OBJECTIVES: The aim of this study was to examine the association between combined lifestyle scores and risk of all-cause and cause-specific mortality for the first time among Iranian adults. METHODS: The study population included 50,045 Iranians, 40 - 75 years of age, who were enrolled in the Golestan Cohort Study, between 2004 and 2008. The lifestyle risk factors used in this study included cigarette smoking, physical inactivity, and Alternative Healthy Eating Index. The lifestyle score ranged from zero (non-healthy) to 3 (most healthy) points. From the study baseline up to analysis, a total of 4691 mortality cases were recorded. Participants with chronic diseases at baseline, outlier reports of calorie intake, missing data, and body mass index of less than 18.5 were excluded from the analyses. Cox regression models were fitted to establish the association between combined lifestyle scores and mortality outcomes. RESULTS: After implementing the exclusion criteria, data from 40,708 participants were included in analyses. During 8.08 years of follow-up, 3,039 cases of all-cause mortality were recorded. The adjusted hazard ratio of a healthy lifestyle score, compared with non-healthy lifestyle score, was 0.68 (95% CI: 0.54, 0.86) for all-cause mortality, 0.53 (95% CI: 0.37, 0.77) for cardiovascular mortality, and 0.82 (95% CI: 0.53, 1.26) for mortality due to cancer. When we excluded the first two years of follow up from the analysis, the protective association between healthy lifestyle score and cardiovascular death did not change much 0.55 (95% CI: 0.36, 0.84), but the inverse association with all-cause mortality became weaker 0.72 (95% CI: 0.55, 0.94), and the association with cancer mortality was non-significant 0.92 (95% CI: 0.58, 1.48). In the gender-stratified analysis, we found an inverse strong association between adherence to healthy lifestyle and mortality from all causes and cardiovascular disease in either gender, but no significant relationship was seen with mortality from cancer in men or women. Stratified analysis of BMI status revealed an inverse significant association between adherence to healthy lifestyle and mortality from all causes, cardiovascular disease and cancer among non-obese participants. CONCLUSION: We found evidence indicating that adherence to a healthy lifestyle, compared to non-healthy lifestyle, was associated with decreased risk of all-cause mortality and mortality from cardiovascular diseases in Iranian adults.