1.The association between physical activity and atrial fibrillation applying the Heaviside function in survival analysis: the Multi-Ethnic Study of Atherosclerosis.
Yaser MOKHAYERI ; Seyed Saeed HASHEMI-NAZARI ; Mohammad Ali MANSOURNIA ; Hamid SOORI ; Soheila KHODAKARIM
Epidemiology and Health 2017;39(1):e2017024-
OBJECTIVES: Although the effect of physical activity (PA) on the incidence of atrial fibrillation (AF) has been studied, contradictory results have been reported. Such discrepancies may reflect the different effects of various types of PA upon AF, as well as gender interactions. Therefore, we aimed to evaluate the associations of PA types (total, moderate/vigorous, and intentional), as well as walking pace, with AF risk in men and women. METHODS: Using the Multi-Ethnic Study of Atherosclerosis Typical Week Physical Activity Survey, 3 PA measures and walking pace were calculated among 6,487 men and women aged 45-84 years. The incidence of AF over approximately 11 years of follow-up was ascertained. The association of each PA measure and walking pace with AF incidence was estimated using multivariable Cox proportional hazard models. An extended Cox model with Heaviside functions (hv) of time was used to estimate the effects of time-varying covariates. RESULTS: During 11 years of follow-up (49,557 person-years), 242 new AF cases occurred. The incidence rate of AF was 48.83 per 10,000 person-years. The proportional hazard (PH) assumption for total PA among women was not met; hence, we used the hv to calculate the hazard ratio. Total PA in women in the hv2 analysis was negatively associated with AF in all 3 models, although for hv1 no significant association was observed. The PH assumption for walking pace among men was not met, and none of the hv showed a statistically significant association between walking pace and AF in men. CONCLUSIONS: These results suggest that PA is inversely associated with AF in women.
Atherosclerosis*
;
Atrial Fibrillation*
;
Female
;
Follow-Up Studies
;
Humans
;
Hydrogen-Ion Concentration
;
Incidence
;
Male
;
Motor Activity*
;
Proportional Hazards Models
;
Survival Analysis*
;
Walking
2.The association between physical activity and atrial fibrillation applying the Heaviside function in survival analysis: the Multi-Ethnic Study of Atherosclerosis
Yaser MOKHAYERI ; Seyed Saeed HASHEMI-NAZARI ; Mohammad Ali MANSOURNIA ; Hamid SOORI ; Soheila KHODAKARIM
Epidemiology and Health 2017;39(1):2017024-
OBJECTIVES: Although the effect of physical activity (PA) on the incidence of atrial fibrillation (AF) has been studied, contradictory results have been reported. Such discrepancies may reflect the different effects of various types of PA upon AF, as well as gender interactions. Therefore, we aimed to evaluate the associations of PA types (total, moderate/vigorous, and intentional), as well as walking pace, with AF risk in men and women.METHODS: Using the Multi-Ethnic Study of Atherosclerosis Typical Week Physical Activity Survey, 3 PA measures and walking pace were calculated among 6,487 men and women aged 45-84 years. The incidence of AF over approximately 11 years of follow-up was ascertained. The association of each PA measure and walking pace with AF incidence was estimated using multivariable Cox proportional hazard models. An extended Cox model with Heaviside functions (hv) of time was used to estimate the effects of time-varying covariates.RESULTS: During 11 years of follow-up (49,557 person-years), 242 new AF cases occurred. The incidence rate of AF was 48.83 per 10,000 person-years. The proportional hazard (PH) assumption for total PA among women was not met; hence, we used the hv to calculate the hazard ratio. Total PA in women in the hv2 analysis was negatively associated with AF in all 3 models, although for hv1 no significant association was observed. The PH assumption for walking pace among men was not met, and none of the hv showed a statistically significant association between walking pace and AF in men.CONCLUSIONS: These results suggest that PA is inversely associated with AF in women.
Atherosclerosis
;
Atrial Fibrillation
;
Female
;
Follow-Up Studies
;
Humans
;
Hydrogen-Ion Concentration
;
Incidence
;
Male
;
Motor Activity
;
Proportional Hazards Models
;
Survival Analysis
;
Walking
3.Associations between dietary risk factors and ischemic stroke: a comparison of regression methods using data from the Multi-Ethnic Study of Atherosclerosis
Seyed Saeed HASHEMI NAZARI ; Yaser MOKHAYERI ; Mohammad Ali MANSOURNIA ; Soheila KHODAKARIM ; Hamid SOORI
Epidemiology and Health 2018;40(1):2018021-
OBJECTIVES: We analyzed dietary patterns using reduced rank regression (RRR), and assessed how well the scores extracted by RRR predicted stroke in comparison to the scores produced by partial least squares and principal component regression models.METHODS: Dietary data at baseline were used to extract dietary patterns using the 3 methods, along with 4 response variables: body mass index, fibrinogen, interleukin-6, and low-density lipoprotein cholesterol. The analyses were based on 5,468 males and females aged 45–84 years who had no clinical cardiovascular disease, using data from the Multi-Ethnic Study of Atherosclerosis.RESULTS: The primary factor derived by RRR was positively associated with stroke incidence in both models. The first model was adjusted for sex and race and the second model was adjusted for the variables in model 1 as well as smoking, physical activity, family and sibling history of stroke, the use of any lipid-lowering medication, the use of any anti-hypertensive medication, hypertension, and history of myocardial infarction (model 1: hazard ratio [HR], 7.49; 95% confidence interval [CI], 1.66 to 33.69; p for trend=0.01; model 2: HR, 6.83; 95% CI, 1.51 to 30.87 for quintile 5 compared with the reference category; p for trend=0.02).CONCLUSIONS: Based primarily on RRR, we identified that a dietary pattern high in fats and oils, poultry, non-diet soda, processed meat, tomatoes, legumes, chicken, tuna and egg salad, and fried potatoes and low in dark-yellow and cruciferous vegetables may increase the incidence of ischemic stroke.
Atherosclerosis
;
Body Mass Index
;
Cardiovascular Diseases
;
Chickens
;
Cholesterol
;
Continental Population Groups
;
Diet
;
Fabaceae
;
Fats
;
Female
;
Fibrinogen
;
Humans
;
Hypertension
;
Incidence
;
Interleukin-6
;
Least-Squares Analysis
;
Lipoproteins
;
Lycopersicon esculentum
;
Male
;
Meat
;
Methods
;
Motor Activity
;
Myocardial Infarction
;
Oils
;
Ovum
;
Poultry
;
Risk Factors
;
Siblings
;
Smoke
;
Smoking
;
Solanum tuberosum
;
Stroke
;
Tuna
;
Vegetables
4.Associations between dietary risk factors and ischemic stroke: a comparison of regression methods using data from the Multi-Ethnic Study of Atherosclerosis.
Seyed Saeed HASHEMI NAZARI ; Yaser MOKHAYERI ; Mohammad Ali MANSOURNIA ; Soheila KHODAKARIM ; Hamid SOORI
Epidemiology and Health 2018;40(1):e2018021-
OBJECTIVES: We analyzed dietary patterns using reduced rank regression (RRR), and assessed how well the scores extracted by RRR predicted stroke in comparison to the scores produced by partial least squares and principal component regression models. METHODS: Dietary data at baseline were used to extract dietary patterns using the 3 methods, along with 4 response variables: body mass index, fibrinogen, interleukin-6, and low-density lipoprotein cholesterol. The analyses were based on 5,468 males and females aged 45–84 years who had no clinical cardiovascular disease, using data from the Multi-Ethnic Study of Atherosclerosis. RESULTS: The primary factor derived by RRR was positively associated with stroke incidence in both models. The first model was adjusted for sex and race and the second model was adjusted for the variables in model 1 as well as smoking, physical activity, family and sibling history of stroke, the use of any lipid-lowering medication, the use of any anti-hypertensive medication, hypertension, and history of myocardial infarction (model 1: hazard ratio [HR], 7.49; 95% confidence interval [CI], 1.66 to 33.69; p for trend=0.01; model 2: HR, 6.83; 95% CI, 1.51 to 30.87 for quintile 5 compared with the reference category; p for trend=0.02). CONCLUSIONS: Based primarily on RRR, we identified that a dietary pattern high in fats and oils, poultry, non-diet soda, processed meat, tomatoes, legumes, chicken, tuna and egg salad, and fried potatoes and low in dark-yellow and cruciferous vegetables may increase the incidence of ischemic stroke.
Atherosclerosis*
;
Body Mass Index
;
Cardiovascular Diseases
;
Chickens
;
Cholesterol
;
Continental Population Groups
;
Diet
;
Fabaceae
;
Fats
;
Female
;
Fibrinogen
;
Humans
;
Hypertension
;
Incidence
;
Interleukin-6
;
Least-Squares Analysis
;
Lipoproteins
;
Lycopersicon esculentum
;
Male
;
Meat
;
Methods*
;
Motor Activity
;
Myocardial Infarction
;
Oils
;
Ovum
;
Poultry
;
Risk Factors*
;
Siblings
;
Smoke
;
Smoking
;
Solanum tuberosum
;
Stroke*
;
Tuna
;
Vegetables
5.Associations between dietary risk factors and ischemic stroke: a comparison of regression methods using data from the Multi-Ethnic Study of Atherosclerosis
Seyed Saeed HASHEMI NAZARI ; Yaser MOKHAYERI ; Mohammad Ali MANSOURNIA ; Soheila KHODAKARIM ; Hamid SOORI
Epidemiology and Health 2018;40():e2018021-
OBJECTIVES:
We analyzed dietary patterns using reduced rank regression (RRR), and assessed how well the scores extracted by RRR predicted stroke in comparison to the scores produced by partial least squares and principal component regression models.
METHODS:
Dietary data at baseline were used to extract dietary patterns using the 3 methods, along with 4 response variables: body mass index, fibrinogen, interleukin-6, and low-density lipoprotein cholesterol. The analyses were based on 5,468 males and females aged 45–84 years who had no clinical cardiovascular disease, using data from the Multi-Ethnic Study of Atherosclerosis.
RESULTS:
The primary factor derived by RRR was positively associated with stroke incidence in both models. The first model was adjusted for sex and race and the second model was adjusted for the variables in model 1 as well as smoking, physical activity, family and sibling history of stroke, the use of any lipid-lowering medication, the use of any anti-hypertensive medication, hypertension, and history of myocardial infarction (model 1: hazard ratio [HR], 7.49; 95% confidence interval [CI], 1.66 to 33.69; p for trend=0.01; model 2: HR, 6.83; 95% CI, 1.51 to 30.87 for quintile 5 compared with the reference category; p for trend=0.02).
CONCLUSIONS
Based primarily on RRR, we identified that a dietary pattern high in fats and oils, poultry, non-diet soda, processed meat, tomatoes, legumes, chicken, tuna and egg salad, and fried potatoes and low in dark-yellow and cruciferous vegetables may increase the incidence of ischemic stroke.
6.Effects of Air Pollution on Public and Private Health Expenditures in Iran: A Time Series Study (1972-2014).
Pouran RAEISSI ; Touraj HARATI-KHALILABAD ; Aziz REZAPOUR ; Seyed Yaser HASHEMI ; Abdoreza MOUSAVI ; Saeed KHODABAKHSHZADEH
Journal of Preventive Medicine and Public Health 2018;51(3):140-147
OBJECTIVES: Environmental pollution is a negative consequence of the development process, and many countries are grappling with this phenomenon. As a developing country, Iran is not exempt from this rule, and Iran pays huge expenditures for the consequences of pollution. The aim of this study was to analyze the long- and short-run impact of air pollution, along with other health indicators, on private and public health expenditures. METHODS: This study was an applied and developmental study. Autoregressive distributed lag estimating models were used for the period of 1972 to 2014. In order to determine the co-integration between health expenditures and the infant mortality rate, fertility rate, per capita income, and pollution, we used the Wald test in Microfit version 4.1. We then used Eviews version 8 to evaluate the stationarity of the variables and to estimate the long- and short-run relationships. RESULTS: Long-run air pollution had a positive and significant effect on health expenditures, so that a 1.00% increase in the index of carbon dioxide led to an increase of 3.32% and 1.16% in public and private health expenditures, respectively. Air pollution also had a greater impact on health expenditures in the long term than in the short term. CONCLUSIONS: The findings of this study indicate that among the factors affecting health expenditures, environmental quality and contaminants played the most important role. Therefore, in order to reduce the financial burden of health expenditures in Iran, it is essential to reduce air pollution by enacting and implementing laws that protect the environment.
Air Pollution*
;
Birth Rate
;
Carbon Dioxide
;
Developing Countries
;
Environmental Pollution
;
Fertility
;
Health Expenditures*
;
Humans
;
Infant
;
Infant Mortality
;
Iran*
;
Jurisprudence
;
Public Health