Iranian Journal of

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Normal 0 false false false EN-US X-NONE AR-SA Background & Objectives: Cardiovascular disease is the first cause of death and third place in disease burden in Iran. This study estimates population attributable fraction (PAF) of cardiovascular risk factors in Tehran population. PAF is one of the important parameters of measuring population affect of risk factors and evaluating potential impact of preventive strategies in community level.
Methods: In this study 5868 participants above 30 years old of Tehran lipid and glucose study (TLGS) were employed and 501 CVD events detected during 10 years follow-up. Direct estimate of adjusted PAFs using logistic regression which is one of less biased exist methods of PAF calculation were applied.
Results: Highest modifiable cardiovascular risk factor PAFs, in sequence, was smoking (14.16%), hypertension (11.73%), diabetes (7.32%), hypercholesterolemia (6.85%) and central obesity (5.91%) for men, and hypertension (19.25%), diabetes (18.82%), central obesity(9.88%) and hypercholesterolemia (7.95%), for women. Also PAF of hazardous age and premature family history of CVD, as most important nonmodifiable CVD risk factors, were 36.09%, 16.61% and 3.95%, 7.56% for men and women respectively.
Conclusion: According to the difference of risk factors PAFs ranking in men and women, it is suitable that CVD preventive interventions to be prioritized by sex separately. In this regard, besides special attention to control tobacco use in men, hypertension and diabetes in both sexes and high cholesterol in men and central obesity in women respectively, should be given in priority of preventive strategies.

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Background & Objectives: The case-cohort study is one of the youngest designs in epidemiology and some methodological aspects of it are still in debate. This study aimed at comparing the estimated hazard ratio, standard error, and interaction hazard ratio between the case-cohort and cohort studies for assessing the relationship between diabetes and cardiovascular diseases.

Methods: A total of 1701 men and 2253 women aged between 40 and 75 years were considered as the main cohort. Subcohort sampling was performed using simple random sampling with a sampling fraction of 0.3%. The hazard ratio of the cohort study was calculated using Cox regression model and the 3 methods of Prentice, Self-Prentice, and Barlow were used for calculating the hazard ratio of the case-cohort study. The mentioned regression models were used to assess the interactions.

Results: The results of the two studies were similar in populations with higher incidence (cohort of men) and lower incidence (the cohort of women) when frequency percent of exposure variable was greater than 10%. When the sample size of the initial cohort was less than 1250 subjects, discrepancies were observed between the results of the two studies. In addition, the standard error of the case-cohort study was higher than the cohort study. The results of both studies were similar in assessing the considered interactions.

Conclusion: The results are similar when the initial cohort sample sizes are sufficient. Meanwhile, unlike the percentage of exposure frequency, the outcome incidence has a negligible impact on the discrepancy between the results while the effect of the relative frequency of the exposure levels on the results discrepancy is noticeable.

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Background and Objectives: The Covid-19 prevalence can threaten self-care behaviors and disease control in people with type 2 diabetes (T2D) through increasing anxiety and stress levels and limited access to medical services. This study was conducted to investigate the association of the Covid-19 pandemic with self-care behaviors in patients with T2D.
 
Methods: The present study was conducted on 318 adults with T2D who participated in the Tehran Lipid and Glucose Study (TLGS) between 1397 and 1399 and completed the summary of diabetes self-care activities (SDSCA) questionnaire. Data on self-care activities during the Covid-19 pandemic were collected 3-4 months after the announcement of the epidemic in the country via telephone calls. For data analysis, a multiple linear regression model and paired t-test were used.
 
Results: The mean total scores of self-care behaviors were 49.7±14.8 and 56.1±13.1 before and after the Covid-19 pandemic, respectively (P<0.001). After the Covid-19 pandemic, women's total self-care score increased with an increase in the diabetes duration (β= 0.31, P= 0.020) after adjusting for the aforementioned related conditions. This score showed a significant decrease in women with a high school education compared to those with higher education (β= -6.57, P= 0.024). Moreover, the diet and foot care subscales in both sexes and the blood glucose testing score in women were significantly higher after versus before the pandemic.
 
Conclusion: Following the Covid-19 pandemic, self-care behaviors, especially those related to diet, foot care, and blood glucose testing, improved in the short term