Multilevel Modeling of PM2.5 and Risk of Cardiovascular Disease and Diabetes Mellitus in Adults Aged 65 and Older

We aimed to test a hypothesis that elevated ambient particulate matter (PM) 2.5 concentrations are significantly associated with risk of coronary heart disease (CHD), stroke, and diabetes mellitus (DM) in adults aged 65 and older. We analyzed data (2010-2013) from U.S. 1118 counties to examine the association between PM2.5 concentrations and risk of prevalent CHD, stroke, and DM, and mortality from cardiovascular disease (CVD), CHD, stroke, and DM in adults aged ≥ 65. Multilevel regression analysis technique was applied to test these associations. The results show that the annual mean of PM2.5 concentration was 8.7 μg/m3 in the total study sample. Significant differences in mean PM2.5 concentrations were observed across counties and states in the U.S. Multilevel regression analysis indicates that an average annual concentration of 1 μg/m3 increase in PM2.5 concentration was significantly associated with an increased prevalence of CHD, stroke, and DM by 4.9‰ (95% CI: 3.1‰ - 6.7‰), 0.8‰ (0.5‰ - 1.1‰), and 3.3‰ (2.9‰ - 4.4‰), respectively. State-level correlation analyses indicate that increased PM2.5 concentrations were significantly associated with increased age-adjusted mortality from CVD (r = 0.76, p < 0.001), CHD (r = 0.0.40, p = 0.004), stroke (r = 0.60, p p = 0.02). In conclusion, Elevated PM2.5 concentrations were significantly associated with an increased risk of the prevalence and mortality from CVD, CHD, stroke, and DM. Continued effort to control ambient PM2.5 concentrations could play an important role in risk reduction of cardiovascular disease and diabetes in the elderly.

Vitamin d deficiency and metabolic syndrome:The joint effect on cardiovascular and all-cause mortality in the United States adults

BACKGROUND The long-term impact of vitamin D deficiency and metabolic syndrome(MetS)on cardiovascular disease(CVD)and all-cause mortality are still a matter of debate.AIM To test the hypotheses that lower serum 25 hydroxyvitamin D[25(OH)D]concentrations(a marker of vitamin D level)and MetS have a long-term impact on the risk of CVD and all-cause mortality,and individuals with vitamin D deficiency can be identified by multiple factors.METHODS A sample of 9094 adults,20 to 90 years of age,who participated in the Third National Health and Nutrition Examination Survey(NHANES III,1988 to 1994)were followed through December 2015 was analyzed.The associations of serum 25(OH)D concentrations and MetS with CVD and all-cause mortality were analyzed longitudinally using Cox regression models.Classification and regression tree(CART)for machine learning was applied to classify individuals with vitamin D deficiency.RESULTS Of 9094 participants,30%had serum 25(OH)D concentrations<20 ng/mL(defined as vitamin D deficiency),39%had serum 25(OH)D concentrations between 20 to 29 ng/mL(insufficiency),and 31%had serum 25(OH)D concentrations≥30 ng/mL(sufficiency).Prevalence of MetS was 28.4%.During a mean of 18 years follow-up,vitamin D deficiency and MetS were significantly associated with increased risk of CVD and all-cause mortality.Subjects with both vitamin D deficiency and MetS had the highest risk of CVD mortality(HR=1.77,95%CI:1.22-2.58)and all-cause mortality(HR=1.62,95%CI:1.26-2.09),followed by those with both vitamin D insufficiency and MetS for CVD mortality(HR=1.59,95%CI:1.12-2.24),and all-cause mortality(HR=1.41,95%CI:1.08-1.85).Meanwhile,vitamin D sufficiency significantly decreased the risk of CVD and all-cause mortality for those who even had MetS.Among the total study sample,CART analysis suggests that being non-Hispanic Black,having lower serum folate level,and being female were the first three predictors for those with serum 25(OH)D deficiency.CONCLUSION Vitamin D deficiency and MetS were significantly associated with increased risk of CVD and allcause mortality.There was a significant joint effect of vitamin D deficiency and MetS on the risk of mortality.Findings of the CART analysis may be useful to identify individuals positioned to benefit from interventions to reduce the risk of CVD and all-cause mortality.