Letter to the Editor Regarding "Nationwide Prevalence of Diabetes and Prediabetes and Associated Risk Factors Among Iranian Adults: Analysis of Data from PERSIAN Cohort Study"

Dietary Diabetes Risk Reduction Score (DDRRS) and Breast Cancer Risk: A Case-Control Study in Iran

INTRODUCTION

Given the role of type 2 diabetes and insulin resistance in tumor initiation, we hypothesized that following a diet that reduces the risk of type 2 diabetes could also reduce the risk of breast cancer. Herein, we conducted a case-control study to investigate the association between dietary diabetes risk reduction score and breast cancer risk in Iranian women.

METHOD

We recruited 136 newly diagnosed cases and 272 age-matched hospitalized controls from referral hospitals. A valid and reliable 168-item food frequency questionnaire (FFQ) was used to collect the data on dietary intake. We used Multivariate Logistic regression to assess the odds ratio (OR) with 95% confidence interval (CI) of breast cancer by the dietary diabetes risk reduction score tertiles.

RESULTS

After adjusting for confounding variables, no association was seen between dietary diabetes risk reduction score and breast cancer risk (OR = 0.65, 95% CI: 0.37-1.14). However, after stratification by menopausal status, a decreased risk was observed between adherence to dietary diabetes risk reduction score and breast cancer risk in postmenopausal individuals (OR = 0.43, 95% CI: 0.19-0.99).

CONCLUSION

The present study states that there is no significant relationship between the dietary diabetes risk reduction score and the risk of breast cancer. However, adherence to dietary diabetes risk reduction score could have a preventive role for breast cancer among postmenopausal women.

The relationship between glucose intolerance status and risk of hospitalization during two decades of follow-up: Tehran lipid and glucose study

OBJECTIVE

To assess the relationship between glucose intolerance statuses at baseline defined as normal glucose tolerance (NGT), pre-diabetes, newly diagnosed (NDM) and known diabetes mellitus (KDM) and all-cause hospitalization among Iranian men and women during 20 years of follow-up.

RESEARCH DESIGN AND METHODS

This study included 8,014 individuals (3,836 men) ≥30 years from the cohort of Tehran Lipid and Glucose Study. Incidence rate ratios (IRRs) and (95% confidence interval (95% CI) for three groups of pre-diabetes, NDM and KDM was estimated using the Negative Binomial regression model, considering NGT group as reference group. Regression models were adjusted for age, body mass index, hypertension, chronic kidney disease, and cardiovascular disease (CVD).

RESULTS

Among men, compared with NGT group, those with pre-diabetes, NDM and KDM had higher incidence rate for hospitalization, with IRRs (95% CI) of 1.08 (0.96-1.20), 1.38 (1.20-1.57) and 1.96 (1.66-2.26), respectively, after adjusting for confounders. The corresponding values were 1.07 (0.96-1.17), 1.40 (1.21-1.59) and 2.07 (1.72-2.42) for women. Men with diabetes, generally had a higher rate of hospitalization for CVD rather than their female counterparts (IRRs: 1.46; 1.17-1.74). In patients with diabetes, the most common causes of hospitalization were macrovascular complications (i.e. coronary heart disease and stroke). Moreover, among the individuals with diabetes, those with poor glycaemic control (fasting plasma glucose (FPG) >10 mmol/l) had 39% higher rate of hospitalization than those with fair glycaemic control (FPG <10 mmol/l) (1.39; 1.12-1.65), adjusted for confounders.

CONCLUSION

Pre-diabetes, NDM, and KDM were associated with increased hospitalization rates during long-term follow-up. Interventions such as lifestyle modification or pharmacological therapies aiming to slow down the pre-diabetes and fair control of diabetes might potentially decrease the rate of hospitalization.Key messagesNDM and KDM status both increased rate of all-cause hospitalization.CVD and T2DM complication were the most common cause of hospitalization among patients with diabetes.Hospitalization due to recurrent CHD was significantly higher in men with diabetes than their female counterparts.

Differences in the impact of impaired glucose status on clinical outcomes in younger and older adults: Over a decade of follow-up in the Tehran lipid and glucose study

Introduction

Studies found that the impact of dysglycemia on microvascular, macrovascular events and mortality outcomes were different between the younger vs. older population. We aimed to investigate the age-specific association of prediabetes with clinical outcomes including type 2 diabetes (T2DM), hypertension, chronic kidney disease (CKD), cardiovascular disease (CVD), and mortality.

Materials and methods

A total of 5,970 Iranians (3,829 women) aged ≥30 years, without T2DM, were included. The age-specific (<60 and ≥60 years; minimum p-value for interaction = 0.001) multivariable-adjusted Cox regression was done to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) of the impaired glucose status including impaired fasting glucose (IFG) vs. normal fasting glucose (NFG), impaired glucose tolerance (IGT) vs. normal glucose tolerance (NGT), and IFG&IGT vs. NFG/NGT with each outcome.

Results

Among individuals aged ≥60 years, the prevalence of impaired glucose status (IFG, IGT, or both) was about 2 times higher compared to those aged <60. Age-specific association between prediabetes and incident hypertension was found for those aged <60 years; [HR (95% CI); IFG: 1.38 (1.16-1.65), IGT: 1.51 (1.26-1.81), and IFG&IGT: 1.62 (1.21-2.12)]. For CVD, in all impaired glycemic states, those aged <60 were at higher significant risk [IFG: 1.39 (1.09-1.77), IGT: 1.53 (1.19-1.97), and IFG&IGT: 1.60 (1.14-2.25)]. Stratified analyses showed similar associations for IFG and IGT with non-CV mortality 1.71 (1.04-2.80) and 2.12 (1.30-3.46), respectively, and for all-cause mortality among those aged <60 years [IFG: 1.63 (1.08-2.45) and IGT: 1.82 (1.20-2.76)]. In both age groups, all glycemic status groups were significantly associated with T2DM but not with CKD and CV mortality.

Conclusions

The high prevalence of prediabetes particularly among the elderly population, limited resources, and the observed significant age differences in the impact of prediabetes states on different clinical outcomes calls for multicomponent intervention strategies by policy health makers, including lifestyle and possible pharmacological therapy, with the priority for the young Iranian population.

The Association of Ideal Cardiovascular Health Metrics and Incident Type 2 Diabetes Mellitus Among an urban population of Iran: a decade follow-up in Tehran Lipid and Glucose Study

AIMS

To evaluate the association between ideal cardiovascular health metrics (ICVHM) and incident type diabetes (T2DM) among Iranian men and women.

METHODS

The study population included 7,488 Iranian adults aged ≥20 years (4236 women) free from diabetes at baseline. The ICVHM was defined according to the 2020-American Heart Association. The multivariable Cox proportional hazards regression analysis was used to calculate the hazard ratios (HRs) for ICVHM both as continuous and categorical variables.

RESULTS

Over the median of 9.1 years of follow-up, we identified 922 new cases of T2DM (526 women). Body mass index <30 kg/m² , untreated systolic/diastolic blood pressure <120/80 mmHg in both genders, and physical activity ≥1500 MET mins/wk (only among men) were significantly associated with a lower risk of T2DM. Each additional unit in the ICVHM was associated with a 21% and 15% lower risk of T2DM in men and women, respectively (p-values<0.05). Compared with participants having poor cardiovascular health (CVH), the HR (95% confidence interval) for T2DM risk was 0.69 (0.56-0.85) and 0.35 (0.21-0.59) for men with intermediate and ideal CVHM, respectively. The corresponding values for women were 0.79 (0.65-0.97) and 0.30 (0.15-0.60), respectively. in a subpopulation with nutritional data (n=2236), ideal and intermediate nutritional status was associated with 83% and 77% lower risk of T2DM only among women (p-values<0.05).

CONCLUSION

We found a strong inverse association between having higher global ICVHM with incident T2DM; the issue is mainly attributable to normal blood pressure, normal body weight, and intensive physical activity (only for men).