Risk factors for ischemic stroke; results from 9 years of follow-up in a population based cohort of Iran

The difference between 2-hour post-challenge and fasting plasma glucose associates with the risk of cardiovascular disease in a normoglycemic population: the Tehran lipid and glucose study

BACKGROUND

Elevated fasting plasma glucose (FPG) and 2-hour post-challenge glucose (2hPG) levels are known to be independent risk factors for cardiovascular disease (CVD). However, there is limited data on the association of the difference between these measures and the risk of CVD. This study aims to investigate this association in normoglycemic Iranian adults, particularly in those with low-normal FPG levels.

METHODS

This prospective cohort study included 4,594 30-65-year-old participants from the Tehran Lipid and Glucose Study. Using multivariable Cox proportional hazards regression models adjusting for age, sex, body mass index, hypertension, hypercholesterolemia, smoking, education level and FPG, hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated for the association between 2hPG-FPG, both as continuous and categorical variables, and the CVD risk. Analyses of receiver operating characteristic curves were undertaken to determine the optimal 2hPG-FPG cut-off value.

RESULTS

During a median of 17.9 years of follow-up, 459 CVD events occurred. A one-unit increase in 2hPG-FPG was significantly associated with an elevated risk of cardiovascular disease in both normoglycemic (HR 1.10, 95% CI (1.01-1.19)) and low-normal FPG individuals (HR 1.16, 95% CI (1.04-1.30)); this association resisted adjustment for Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) among normoglycemic individuals. However, those with 2hPG levels greater than FPG levels had a non-significant increased risk of incident CVD compared to those with 2hPG levels of less than or equal to FPG, with corresponding HR values of 1.18 (95% CI: 0.95-1.46) in normoglycemic and 1.32 (95% CI: 0.98-1.79) in low-normal FPG, respectively. For incident CVD, the optimal cut-off value for the 2hPG-FPG was found to be 1.06 mmol/L, which was applicable for both normoglycemic and low FPG populations; using this criterion, the corresponding risks for incident CVD were 1.36 (95% CI: 1.12-1.64) and 1.57 (95% CI: 1.22-2.03), respectively.

CONCLUSIONS

The difference between 2hPG and FPG levels within the normoglycemic range is related to an increased risk of CVD, an issue that was independent of HOMA-IR. A cut-off point for 2hPG-FPG > 1.06 mmol/L may stratify persons at higher risk. These findings were particularly notable in those with low-normal FPG.

The association between metabolic syndrome and insulin resistance with risk of cardiovascular events in different states of cardiovascular health status

AIMS/INTRODUCTION

The aim was to examine the joint effect of metabolic syndrome (MetS) and insulin resistance (IR) with ideal cardiovascular health (iCVH) status on incident cardiovascular diseases (CVDs).

MATERIALS AND METHODS

The study included 6,240 Iranian adults ≥30 years, free of prior cardiovascular disease. Ideal cardiovascular health was determined based on American Heart Association's Life Simple 7. Metabolic syndrome was defined according to the Joint Interim Statement Criteria, and insulin resistance was defined as HOMA-IR ≥1.85 in women and ≥2.17 in men. Multivariable Cox proportional hazard ratios (HRs) were applied to examine the impact of metabolic syndrome, and insulin resistance at various levels of iCVH status.

RESULTS

During the median follow-up of 14.0 years, 909 cases of cardiovascular disease occurred. Metabolic syndrome and insulin resistance were significantly associated with incident cardiovascular disease events. In the poor and intermediate status, metabolic syndrome increased cardiovascular disease events with HRs of 1.83 and 1.57, respectively; the corresponding values for insulin resistance in the mentioned categories were 1.91 and 1.25, respectively (P values < 0.05). In the intermediate and poor iCVH status, hypertriglyceridemia was linked to a 40% and 35% higher risk of cardiovascular disease, the corresponding values for low HDL-C was 20% and 60%, respectively (P values < 0.05). Although adding metabolic syndrome, its dyslipidemia and insulin resistance to iCVH status in both poor and intermediate status significantly improve the prediction of cardiovascular disease using net reclassification improvement (P values < 0.05), the value of C-index did not change.

CONCLUSIONS

Metabolic syndrome and the dyslipidemia component had a negligible but significant improvement in the prediction of cardiovascular disease among individuals with non-optimal iCVH status.

Does the addition of serum antimüllerian hormone concentrations to the Framingham Risk Score and Pooled Cohort Equations improve the prediction of cardiovascular disease?

The present study revealed that the addition of serum antimüllerian hormone concentrations to Framingham Risk Score and Pooled Cohort Equations could potentially improve the risk prediction of cardiovascular disease.

Objective

The current study aimed to examine the added value of serum antimüllerian hormone (AMH) concentration to the Framingham Risk Score (FRS) and Pooled Cohort Equations (PCE) in predicting the risk of cardiovascular disease (CVD) in women of reproductive age.

Methods

Women 30 years and older were considered eligible for this population-based prospective study. The univariate and multivariate Cox proportional hazard models were used to evaluate the association between the serum concentrations of AMH and the risk of CVD.

Results

In the enhanced model, which integrated AMH into FRS and PCE and was adjusted for family history of premature CVD, AMH showed a significant association with the risk of CVD during a 19-year follow-up of 800 women (hazard ratio, 0.77 [95% CI, 0.60-0.99] and hazard ratio, 0.64 [95% CI, 0.48-0.84], respectively). According to the likelihood-ratio test, the addition of AMH measurements to FRS and PCE could significantly improve the risk prediction of CVD (P = 0.02 and P < 0.001, respectively); however, the integration of this biomarker did not improve the classification of risk categories.

Conclusions

The present findings revealed that the addition of serum AMH concentrations to FRS and PCE could potentially improve the risk prediction of CVD.

Population attributable fraction estimates of cardiovascular diseases in different blood pressure levels in a large-scale cross-sectional study: a focus on prevention strategies and treatment coverage

OBJECTIVE

Hypertension is one of the major modifiable risk factors in developing cardiovascular diseases (CVD). Hence, we aimed to ascertain age- and sex-specific population attributable fraction (PAF) for CVD in different blood pressure levels to implement efficient preventive strategies at the population level.

METHODS

Participants' data were obtained from the Iranian stepwise approach for surveillance of noncommunicable disease risk factors (STEPs) survey to calculate PAF in four subsequent phases. In phase 0, PAF was measured, irrespective of the diagnosis status. In phase 1, the theoretical minimum range of 115 ≤SBP less than 130 mmHg was considered as the low-risk and measurements equal to or higher than 130 mmHg as the high-risk group. Across phase 2, patients were divided into normal and hypertensive groups based on the American College of Cardiology/American Heart Association guideline. In phase 3, patients were divided into two categories based on treatment coverage.

RESULTS

A total number of 27 165 participants aged ≥25 years had valid blood pressure measurements and were enrolled. Phase 0: PAF generally had an upward trend with age advancing. Phase 1: participants with BP ≥130 mmHg comprised the largest PAF, extending from 0.31 (0.25-0.37) in older male individuals to 0.85 (0.79-0.91) in younger females. Phase 2: higher values were found in younger ages for hypertension. Phase 3 represented that attributable fractions among hypertensive patients who received treatment were much lower than drug-naïve hypertensive participants.

CONCLUSION

Our study enlightens the necessity for implementing effective screening strategies for the younger generation and providing adequate access to antihypertensive medications for the low-risk population.

Risk profile, clinical presentation, and determinants of stroke subtypes among patients with stroke admitted to public referral hospitals, Northwest Ethiopia in 2021: A cross-sectional study

Background

Stroke is the second leading cause of death worldwide, with a significant increase in stroke burden over the last two and half decades, especially in developing countries. African countries are undergoing an epidemiological transition from being dominated by infectious diseases to being double-burdened by non-communicable diseases, with existing infectious diseases driven by sociodemographic and lifestyle changes and a weak healthcare system. Data on the risk profile, clinical presentation, and predictors of stroke subtypes are still limited. Therefore, the main aim of this study was to assess the risk profile, clinical presentation, and predictors of stroke in public referral hospitals of Northwest Ethiopia.

Methods

For this study, 554 patients with stroke admitted to three public referral hospitals were prospectively followed up. Data were collected using a pre-tested interviewer-administered questionnaire. STATA version 16 was used for data analyses. Candidate variables significant in bivariate analysis were selected for multivariate binary logistic regression, and statistical significance was set at a p &lt; 0.05.

Results

Of the 554 patients with stroke, 60.3% had an ischemic stroke. The mean age of the participants was 61 ± 12.85 years, and more than half (53.25%) of them were women. The most common risk factor identified was hypertension (29.7%), followed by congestive heart failure. The most common clinical presentation was hemiparesis, which was reported by 57.7% of the patients, followed by loss of consciousness (20.7%) and aphasia (9%). Through multivariable logistic regression, age (AOR = 1.03, 95% CI:1.01–1.05), sedentary physical activity level (AOR = 6.78, 95% CI:1.97–23.32), absence of a family history of chronic illness (AOR = 3.79, 95% CI:2.21–6.48), hypertension (AOR=0.51, 95% CI:0.31–0.85), and past stroke (AOR = 3.54, 95% CI:0.93–13.49) were found to be independent determinants of the stroke subtype.

Conclusion

Age, the level of sedentary physical activity, absence of a family history of chronic illness, hypertension, and past stroke were independent determinants of stroke subtype.

Incidence, early case fatality and determinants of stroke in Iran: Golestan Cohort Study

OBJECTIVES

While few studies investigated the incidence of stroke in Iran, no Iranian cohort has estimated the standardized-incidence rate and early fatality of first-ever-stroke subtypes along with associated factors.

METHODS

Golestan Cohort Study is a prospective study launched in northeastern Iran in 2004, including 50,045 individuals aged 40-75 at baseline. Age-standardized incidence rate of first-ever-stroke was calculated per 100,000 person-years, according to World Standard Population. The 28-day case fatality was calculated by dividing the number of fatal first-ever-stroke during the first 28 days by total events. Cox proportional hazard models were conducted to assess incidence and fatality risk factors. We used Population Attributable Fractions to estimate the incidence and early fatality proportions reduced by ideal risk factor control.

RESULTS

1,135 first-ever-strokes were observed during 8.6 (median) years follow-up. First-ever-stroke standardized incidence rate was estimated 185.2 (95% CI: 173.2-197.2) per 100,000 person-years. The 28-day case fatality was 44.1% (95% CI: 40.4-48.2). Hypertension and pre-stroke physical activity were the strongest risk factors associated with first-ever-stroke incidence (Hazard ratio: 2.83; 2.47-3.23) and 28-day case fatality (Hazard ratio: 0.59; 0.44-0.78), respectively. Remarkably, opium consumption was strongly associated with hemorrhagic stroke incidence (Hazard ratio: 1.52; 1.04-2.23) and ischemic stroke fatality (Hazard ratio: 1.44; 1.01-2.09). Overall, modifiable risk factors contributed to 83% and 61% of first-ever-stroke incidence and early fatality, respectively.

CONCLUSION

Efficient risk factor control can considerably reduce stroke occurrence and fatality in our study. Establishing awareness campaigns and 24-hour stroke units seem necessary for improving the stroke management in this area.

Ideal cardiovascular health status and risk of cardiovascular disease and all-cause mortality: over a decade of follow-up in the Tehran lipid and glucose study

Objective

To quantify the association between ideal cardiovascular health (CVH) metrics and incident cardiovascular disease (CVD) including different subtypes [coronary heart disease (CHD), stroke, and sudden death], and all-cause mortality in an Iranian population.

Methods

The study population included 6,388 participants (2,726 men) aged 48.0 ± 12.4 years free of CVD at baseline. We utilized the American Heart Association’s 2020 impact target criteria of ideal, intermediate, and poor CVH. The multivariate Cox proportional Hazard model, adjusted for age, sex, educational level, marital status, and family history of CVD, was applied to estimate the hazard ratio (HR) of outcomes per one additional metric of ideal CVH metrics. Furthermore, the risk was also calculated for ideal and intermediate categories considering poor category as a reference.

Results

During the median follow-up of 11.26 years, 692 CVD, 589 CHD, 130 stroke, 111 sudden death, and 519 all-cause mortality events were reported. All of the individual ideal CVH metrics were independent predictors except intermediate physical activity level for CVD, BMI &lt; 25 kg/m2, and intermediate physical activity for all-cause mortality. Each additional metrics of ideal CVH decreased the risk by 31 (0.69, 0.65–0.73) for CVD, 32 (0.68, 0.64–0.73) for CHD, 31 (0.69, 0.60–0.80) for stroke, 25 (0.75, 0.64–0.88) for sudden death, and 13% (0.87, 0.81–0.93) for all-cause mortality events. Moreover, intermediate and ideal categories of CVH metrics were associated with lower risk for different CVD outcomes, i.e., 44 (0.56, 0.48–0.65) and 76% (0.24, 0.17–0.35) for CVD; 43 (0.57, 0.47–0.67) and 75% (0.25, 0.16–0.37) for CHD, 58 (0.42, 0.29–0.61) and 86% (0.14, 0.04–0.44) for stroke; 56 (0.44, 0.29–0.66) and 55% (0.45, 0.21–0.99) for sudden death; and 25 (0.75, 0.62–0.90) and 46% (0.54, 0.37–0.80) for all-cause mortality events, respectively. We also assessed the impact of changes in ideal CVH status from phase III to phase IV (2008–2011) on CVD events among 5,666 participants. Accordingly, compared to those remaining in the poor category, all of the changes in ideal CVH categories showed a lower risk for CVD events.

Conclusion

Among the Iranian population, meeting higher ideal CVH metrics is associated with a lower risk of different CVD events and mortality outcomes.

Risk factors for incident cardiovascular events among adults in low- and middle-income countries: A systematic review and meta-analysis of prospective cohort studies

The relative contributions of risk factors for cardiovascular events at a population level has received little attention in low- and middle-income countries (LMICs). We estimated the population attributable fraction (PAF) of risk factors associated with incident cardiovascular events in LMICs. We searched six databases for relevant articles, supplemented with a manual search of reference lists. Articles included in the meta-analyses were those based on prospective community-based cohorts and incorporating adjusted hazard ratios (HR) or relative risks with 95% confidence intervals (95% CI) for associations between risk factors and a composite cardiovascular and/or stroke endpoint. Pooled HRs and 95% CI were calculated using the random effects model. We assessed heterogeneity using the I² test and study quality using the Newcastle-Ottawa Scale. We calculated the PAF of each associated risk factor. The protocol was registered in PROSPERO (CRD42019122741). We identified 18 cohorts from LMICs with 1,125,846 participants, 77,045 composite cardiovascular events and 42,216 strokes. Substantial proportions of incident cardiovascular events were attributable to hypertension (HR [95% CI], 2.23 [2.01-2.48], PAF = 28%); current smoking (1.44 [1.31-1.58], PAF = 10%); and diabetes mellitus (1.93 [1.67-2.23], PAF = 8%). Other risk factors identified included number of children, depression, bone mineral density, and air pollution. A substantial proportion of incident cardiovascular events were linked to traditional metabolic and behavioural modifiable risk factors. However, other novel risk factors also appear to contribute. Targeting of these established and novel risk factors has the potential to reduce the burden of CVD in LMICs.

Effects of the liaison nurse management on the infectious stroke complications: a randomized controlled trial

Background

Two of the most serious complications after stroke are pneumonia, and urinary tract infection. Liaison nurse, from hospital admission to discharge and then at home helps patients with complicated caring issues stroke. This study investigates the effect of liaison nurse management on the incidence of pneumonia and urinary tract infection in patients with stroke after discharge from the hospital.

Methods

This randomized controlled trial was conducted on 80 patients in a hospital in Iran. The intervention group was assessed and developed a caring program by the liaison nurse and the control group received routine care. Two weeks and two months after discharge, the patients were evaluated for the incidence of pneumonia and urinary tract infection. Collected data were analyzed using the Chi-square test. P < 0.05 was considered statistically significant.

Results

The two groups were homogenous in terms of mean age; gender frequently distribution and having urinary catheter. The incidence of pneumonia in intervention and control groups (11.6% vs. 19.2%, P = 0.35) had no statistically significant differences, but there was a significant difference in the incidence of urinary tract infection (0% vs. 24.6%, P < 0.001).

Conclusions

With liaison nurse performance, there was a significant difference in the incidence of urinary tract infection, in two months after discharge from hospital, but the incidence of pneumonia had no statistically significant differences in two groups. Nurse’s evaluation each patient individually according to needs, developing and monitoring the home-based care program, beyond overall education to these patients, could reduce some of complications of a stroke.

Trial registration

This study is retrospectively registered by Iranian Registry of Clinical Trials with decree code: IRCT20170605034330N3 on April 4, 2018.

Public Stroke Knowledge, Awareness, and Response to Acute Stroke in Isfahan Iran: What is Less or Misinterpreted in Developing Countries

BACKGROUND

Considering the high burden of stroke in developing countries, it is important for the community to have adequate information and awareness of this disease. In this study, the baseline knowledge of an Iranian population towards stroke has been evaluated.

METHOD

This study was conducted in a governmental hospital in Isfahan, Iran. The participants were selected from the companions of non-cardio-vascular hospitalized patients. A self-administered questionnaire was designed for gathering information RESULTS: A total of 630 questionnaires were analysed. Hypertension and stress were the most frequently identified risk factors (recognised by 83.7% and 75.8% respectively), while pregnancy, oral contraceptives, and anti-coagulants were the least (recognised by 3.5%, 14.2% and 15.8% respectively). Knowledge of other important risk factors such as cardiac diseases was also relatively low (39.4%). Sudden visual difficulties and irrelevant speech were the least identified warning signs of stroke (45.3% and 34.6% respectively), however, knowledge towards all other warning signs was moderately good (each identified by 60-70%). Importantly only 44.2% of respondents were aware that stroke treatment should be started within the first 3 hours. Participants tended to have moderately good insight of most stroke complications and rehabilitation (60-70%). Urban residence, high level of education and knowing someone with a history of stroke were significant predictors of a higher level of stroke awareness.

CONCLUSION

The findings of this study indicate that there is a need to improve general knowledge of cardiac and hypercoagulable related risk factors. Furthermore, understanding of the importance of time critical stroke management and the ineffectiveness of traditional medicine needs to be raised in the general community.

Combined effect of high depressive symptom burden and hypertension on new-onset stroke: evidence from a nationwide prospective cohort study

OBJECTIVE

The aim of this study was to investigate whether the combination of high depressive symptom burden and hypertension increased the risk of stroke among the middle-aged and elderly Chinese using a nationwide prospective study.

METHODS

Data from the China Health and Retirement Longitudinal Study (CHARLS) during 2011-2015 were used. A total of 12 604 Chinese participants aged 45 years and older were included for final analysis. Multivariate Cox proportional hazards regression model was used to explore the associations between high depressive symptom burden, hypertension and new-onset stroke.

RESULTS

There were 244 stroke events occurred during a 4-year follow-up. Compared with those without high depressive symptom burden and hypertension, the adjusted hazard ratios (95% confidence intervals) were 1.96 (1.13-3.42) for individuals with high depressive symptom burden alone, 2.84 (1.77-4.57) for individuals with hypertension alone and 4.38 (2.66-7.20) for individuals with comorbid high depressive symptom burden and hypertension, respectively. In the subgroup analyses, people with the coexistence of high depressive symptom burden and hypertension had the highest risk of new-onset stroke in all subgroups.

CONCLUSION

Our results suggest a combined effect of high depressive symptom burden and hypertension on stroke risk among the middle-aged and elderly Chinese.

A genetic variant in the promoter of lncRNA MALAT1 is related to susceptibility of ischemic stroke

Background

Metastasis-associated lung adenocarcinoma transcript-1 (MALAT1) was aberrantly expressed in diverse diseases. Particularly in ischemic stroke (IS), the abnormal expression of MALAT1 played important roles including promotion of angiogenesis, inhibition of apoptosis and inflammation and regulation of autophagy. However, the effects of genetic variation (single nucleotide polymorphisms, SNPs) of MALAT1 on IS have rarely been explored. This study aimed to investigate whether SNPs in promoter of MALAT1 were associated with the susceptibility to IS.

Methods

A total of 316 IS patients and 320 age-, gender-, and ethnicity-matched controls were enrolled in this study. Four polymorphisms in the promoter of MALAT1 (i.e., rs600231, rs1194338, rs4102217, and rs591291) were genotyped by using a custom-by-design 48-Plex SNPscan kit.

Results

The rs1194338 C > A variant in the promoter of MALAT1 was associated with the risk of IS (AC vs. CC: adjusted OR = 0.623, 95% CI, 0.417–0.932, P = 0.021; AA vs. CC: adjusted OR = 0.474, 95% CI, 0.226–0.991, P = 0.047; Dominant model: adjusted OR = 0.596, 95% CI, 0.406–0.874, P = 0.008; A vs. C adjusted OR = 0.658, 95% CI, 0.487–0.890, P = 0.007). The haplotype analysis showed that rs600231-rs1194338-rs4102217-rs591291 (A-C-G-C) had a 1.3-fold increased risk of IS (95% CI, 1.029–1.644, P = 0.027). Logistic regression analysis identified some independent impact factors for IS including rs1194338 AC/AA, TC, TG, HDL-C, LDL-C, Apo-A1, Apo-B and NEFA (P < 0.05).

Conclusions

These results suggest that the rs1194338 AC/AA genotypes may be a protective factor for IS.

What causes the burden of stroke in Scotland? A comparative risk assessment approach linking the Scottish Health Survey to administrative health data

Background

The availability of robust evidence to inform effective public health decision making is becoming increasingly important, particularly in a time of competing health demands and limited resources. Comparative Risk Assessments (CRA) are useful in this regard as they quantify the contribution of modifiable exposures to the disease burden in a population. The aim of this study is to assess the contribution of a range of modifiable exposures to the burden of disease due to stroke, an important public health problem in Scotland.

Methods

We used individual-level response data from eight waves (1995–2012) of the Scottish Health Survey linked to acute hospital discharge records from the Scottish Morbidity Record 01 (SMR01) and cause of death records from the death register. Stroke was defined using the International Classification of Disease (ICD) 9 codes 430–431, 433–4 and 436; and the ICD10 codes I60-61 and I63-64 and stroke incidence was defined as a composite of an individual’s first hospitalisation or death from stroke. A literature review identified exposures causally linked to stroke. Exposures were mapped to the layers of the Dahlgren & Whitehead model of the determinants of health and Population Attributable Fractions were calculated for each exposure deemed a significant causal risk of stroke from a Cox Proportional Hazards Regression model. Population Attributable Fractions were not summed as they may add to more than 100% due to the possibility of a person being exposed to more than one exposure simultaneously.

Results

Overall, the results suggest that socioeconomic factors explain the largest proportion of incident stroke hospitalisations and deaths, after adjustment for confounding. After DAG adjustment, low education explained 38.8% (95% Confidence Interval 26.0% to 49.4%, area deprivation (as measured by the Scottish Index of Multiple Deprivation) 34.9% (95% CI 26.4 to 42.4%), occupational social class differences 30.3% (95% CI 19.4% to 39.8%), high systolic blood pressure 29.6% (95% CI 20.6% to 37.6%), smoking 25.6% (95% CI 17.9% to 32.6%) and area deprivation (as measured by the Carstairs area deprivation Index) 23.5% (95% CI 14.4% to 31.7%), of incident strokes in Scotland after adjustment.

Conclusion

This study provides evidence for prioritising interventions that tackle socioeconomic inequalities as a means of achieving the greatest reduction in avoidable strokes in Scotland. Future work to disentangle the proportion of the effect of deprivation transmitted through intermediate mediators on the pathway between socioeconomic inequalities and stroke may offer additional opportunities to reduce the incidence of stroke in Scotland.

Blood Pressure and Hypertension: Findings from 20 Years of the Tehran Lipid and Glucose Study (TLGS)

CONTEXT

Hypertension (HTN) is a well-known modifiable risk factor for cardiovascular disease (CVD), chronic kidney disease and mortality. Positive effects of blood pressure (BP) lowering for prevention of CVD and death have been documented in several meta-analyses of randomized controlled trials.

EVIDENCE ACQUISITION

This review focuses on the key findings derived from the Tehran lipid and glucose study (TLGS) papers on different aspects of BP and HTN.

RESULTS

A prevalence of 23% for HTN has been reported in the TLGS population, aged ≥ 20 years. Over a decade long follow-up, the crude incidence rate (95% CI) of new-onset HTN defined as systolic BP (SBP) ≥ 140 mmHg and/or diastolic BP (DBP) ≥ 90 mmHg, and not using antihypertensive medication was 33.63 (32.0 - 35.3) per 1000 person-years. Age, baseline SBP and body mass index were significant risk factors for development of isolated systolic HTN; regarding isolated diastolic HTN, baseline DBP and waist circumference were recognized as important risk factors whereas age, female gender and marriage were shown to be protective factors. SBP decreased significantly in both diabetic and non-diabetic participants; DBP showed a non-significant decrease in diabetic men and a statistically significant decrease in non-diabetic men. Among women, both those with and without diabetes (DM) generally experienced statistically significant decreases in DBP. Cox proportional hazard models showed that neither SBP nor DBP were associated with incident DM in the total population and in either gender, separately. All BP components were associated with CVD and all-cause mortality in the middle-aged population. Contribution of HTN to cerebrovascular events was also documented in the TLGS participants, aged ≥ 50 years.

CONCLUSIONS

Several important findings regarding BP/HTN have been derived from the TLGS. According to data regarding the prevalence and incidence of preHTN and HTN and their contribution to cardiovascular morbidity and mortality in the TLGS population as a representative sample of Tehranian population, it is recommended that interventions be prioritized for lifestyle modifications for the prevention and appropriate management of preHTN/HTN.

Legacy of the Tehran Lipid and Glucose Study: Chronic Kidney Disease

CONTEXT

Chronic kidney disease (CKD), is correlated with a substantial upsurge in mortality and morbidity worldwide. In this review, we aimed to review the 20-year-findings on CKD of the Tehran lipid and glucose study (TLGS).

EVIDENCE ACQUISITION

We conducted a systematic review of all studies on CKD that had been performed in the context of TLGS.

RESULTS

Age adjusted prevalence of CKD, according to estimated glomerular filtration rate (eGFR) assessed with the two abbreviated equations of the modification of diet in renal disease (MDRD) and the CKD epidemiology collaboration (CKD-EPI) were 11.3% (95% confidence interval (CI): 10.7, 12.0) and 8.5% (95% CI: 7.9, 9.1), respectively. Using MDRD equation, over a mean follow up of 9.9 years, the incidence density rates of CKD were 285.3 person years in women and 132.6 per 10000 person-years in men. Studies on the TLGS population documented that abdominal adiposity defined as waist circumference (WC) categories (P for trend < 0.02) and waist gain in men (hazard ratio (HR) = 1.7, CI: 1.3, 2.2) significantly affected CKD development. Also, CKD had a significant effect on coronary heart disease (CHD) only in participants with low body mass index (HR = 2.06; CI: 1.28, 3.31 and HR = 2.56; CI: 1.04, 6.31 in men and women, respectively). Moreover, CKD was among the strongest independent predictors of stroke (HR = 2.01, CI: 1.22, 3.33). Also, compared to diabetic patients, an abnormal ECG was more prevalent in moderate CKD (P = 0.02).

CONCLUSIONS

Increased waist circumference and waist gain (only in men) were associated with developing CKD in the TLGS population. CKD was an independent predictor of CHD (in lean individuals) and stroke.

Diabetes Mellitus: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

We summarized findings from Tehran lipid and glucose study (TLGS) about different aspects of type 2 diabetes (T2D) over the span of nearly 2 decades.

EVIDENCE ACQUISITION

A review was undertaken to retrieve papers related to all aspects of T2D from the earliest date available up to January 30, 2018.

RESULTS

An annual crude incidence rate of 10 per 1000 person-years of follow-up was found for T2D in adult participants. Overall incidence rate of pre-diabetes/T2D was 36.3 per 1000 person-years or about 1% each year among youth. Diabetes was associated with increased risk of CVD [hazard ratio (HR): 1.86, 95% confidence interval (95% CI): 1.57 - 2.27] and mortality [HR: 2.56; 95% CI: 2.08 - 3.16] in the total population. Compared with non-diabetic men and women, their diabetic counterparts survived 1.4 and 0.7 years shorter, respectively, during 15 years of follow-up. Wrist circumference, hyperinsulinaemia, 25-hydroxy vitamin D and increase in alanin aminotranferase provided incremental prognostic information beyond the traditional risk factors for incident T2D in adults. Using decision tree algorithms, a number of high risk groups were found for incident T2D. A probability of 84% was found for incidence of T2D among a group of men with fasting plasma glucose (FPG) > 5.3 mmol/L and waist to height ratio (WHtR) > 0.56, and women with FPG > 5.2 mmol/L and WHtR > 0.56.

CONCLUSIONS

Original TLGS studies have contributed greatly to clarify important evidence regarding the epidemiology and risk factors for T2D among Iranian population.

Tobacco Smoking: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

Smoking is a global public health priority and accurate data of the local population is essential to improve the health policies against its use. Hence, this study aimed to summarize the important findings available on the prevalence of smoking and its association with non-communicable diseases, documented by one of the largest prospective community-based studies of Iran.

EVIDENCE ACQUISITION

All articles derived from the Tehran Lipid and Glucose Study (TLGS) in the last two decades, from the earliest publications until 30 January 2018 were reviewed for their findings on tobacco smoking.

RESULTS

The prevalence of smoking in non-diabetic adults ≥ 20 years increased between baseline (phase I, 1999 - 2001) and follow-up (phase V, 2008 - 2011) from 25.5% to 35.4% among men and from 3.4% to 6.8% among women. In TLGS adolescents (10 - 18 years) water pipe use increased between 2003 and 2005 from 35.5% to 40.9% among boys and from 19.7% to 26.1% among girls. Regarding health hazards, smoking in men was associated with increased risk of combined impaired fasting glucose/impaired glucose tolerance [hazard ratio (HR) 1.69; confidence interval (CI) 95% 1.15 - 2.48] and hypertension (HR 1.26; CI 95% 0.98 - 1.63). Moreover, men, even smoking less than 10 cigarettes per day, were at increased risk for cardiovascular diseases by HR 2.12 (CI 95% 1.14 - 3.95). For women, the risk of chronic kidney disease dramatically increased 5.74-fold (CI 95% 2.71 - 12.15) among smokers. In the whole population, smoking contributed to 7.7% of all-cause mortality with HR 1.75 (CI 95% 1.38 - 2.22). Other health aspects of tobacco smoke, including its impact on metabolic status, thyroid function, female reproductive system and life style have also been reviewed.

CONCLUSION

Considering hazards of smoking, there is the urgency for more effective preventive measures in Iran; emphasizing the need for further local studies on the hazards of smoking with special attention to women and adolescents and the independent hazards of water pipe use.

Prevalence of Stroke Risk Factors and Their Distribution Based on Stroke Subtypes in Gorgan: A Retrospective Hospital-Based Study-2015-2016

Background

Stroke is a leading cause of death and disability worldwide. According to the Iranian Ministry of Medical Health and Education, out of 100,000 stroke incidents in the country, 25,000 lead to death. Thus, identifying risk factors of stroke can help healthcare providers to establish prevention strategies. This study was conducted to investigate the prevalence of stroke risk factors and their distribution based on stroke subtypes in Sayad Shirazi Hospital, Gorgan, Northeastern Iran.

Material and Methods

A retrospective hospital-based study was conducted at Sayad Shirazi Hospital in Gorgan, the only referral university hospital for stroke patients in Gorgan city. All medical records with a diagnosis of stroke were identified based on the International Classification of Diseases, Revision 10, from August 23, 2015, to August 22, 2016. A valid and reliable data gathering form was used to capture data about demographics, diagnostics, lifestyle, risk factors, and medical history.

Results

Out of 375 cases, two-thirds were marked with ischemic stroke with mean ages (standard deviation) of 66.4 (14.2) for men and 64.6 (14.2) for women. The relationship between stroke subtypes and age groups (P=0.008) and hospital outcome (P=0.0001) was significant. Multiple regression analysis showed that hypertension (Exp. (B) =1.755, P=0.037), diabetes mellitus (Exp. (B) =0.532, P=0.021), and dyslipidemia (Exp. (B) =2.325, P=0.004) significantly increased the risk of ischemic stroke.

Conclusion

Overall, hypertension, diabetes mellitus, and dyslipidemia were the major risk factors of stroke in Gorgan. Establishment of stroke registry (population- or hospital-based) for the province is recommended.

Impact of blood pressure, cholesterol and glucose in the association between adiposity measures and coronary heart disease and stroke among Iranian population

BACKGROUND & AIMS

To determine the association of body mass index (BMI) and central adiposity measures with coronary heart disease (CHD)/stroke, and to quantify the impact of blood pressure, cholesterol and glucose as metabolic mediators on these associations.

METHODS

The study population included 4631 Iranian participants (males = 2066) aged ≥40 years. Cox proportional hazard model was used to estimate the hazard ratio (HR) of BMI and central adiposity measures, using continuous and categorical variables, on CHD/stroke, with and without adjustment for three metabolic mediators, to calculate the attenuation of excess risk after adjustment for mediators.

RESULTS

During a median follow-up of 12.1 years, 606 and 132 subjects experienced incident CHD and stroke, respectively. In the sex and confounders adjusted model, overweight and obesity were associated with increased risk for CHD (HR: 1.56; 95% CI: 1.26-1.92) and [1.53 (1.21-1.94)], respectively; however, after further adjustment for all the mediators, the result was significant only for overweight status [1.29 (1.05-1.59)]. Considering stroke, a significant risk of 70% (1.05-2.72) was found only among obese population. The percentage of risk mediated by three mediators among obese population was 75.47% and 75.71% for CHD and stroke, respectively. Blood pressure was the most important mediator of obesity, accounting for at least 50% of the excess risk for CHD and 60% for stroke. Considering central obesity measures, in the presences of all mediators, a significant risk for CHD was demonstrated; regarding stroke events, the risk was marginally significant for waist to height [1.02 (0.99-1.05)] and waist to hip ratios [1.02 (1.00-1.05)].

CONCLUSIONS

Overweight and obesity for CHD and, obesity for stroke were associated with increased risk; the negative effect of obesity was potentially ameloriated about 70% after adjustment for mediators. However, overweight status and central adiposity highlighted significant risk that did not decrease after controlling for traditional risk factors.

Stroke mimics in patients with clinical signs of stroke

Background:

Stroke mimic is a major diagnostic challenge and may be difficult to distinguish from real strokes. The aim of this study was to evaluate the relative frequency of stroke mimics in patients with clinical signs of stroke.

Methods:

In this cross sectional-study, the medical records of 1985 patients with stroke admitted to Poursina Hospital were enrolled using the census technique. Data collection tool was a checklist which include age, sex, imaging results (MRI and CT scan and primary and final diagnoses.

Results:

Of the 1985 patients, 295 (14.9%) were identified with brain stroke mimics. The mean age in the group of patients with mimics and real stroke were 66.5±16.4 years and 72.4±9.6 years, respectively. The highest number of stroke belonged to 61-80 years in stroke groups (68.8%) and mimics (58.3%), respectively. There was a significant correlation between age and early diagnosis of stroke or stroke mimic (P<0.0001). The highest frequency of stroke mimics was related to brain tumors (10.5%), hypoglycemia (9.2%) and toxic poisoning (8.5%).

Conclusion:

Due to the high number of stroke mimics, further attention is necessary to aid in differential diagnosis and clinical procedures in patients with stroke signs.

Smoking, Hypertension, and Their Combined Effect on Ischemic Stroke Incidence: A Prospective Study among Inner Mongolians in China

OBJECTIVE

We intended to investigate the combined effect of smoking and hypertension on ischemic stroke incidence based on a 10-year prospective study among Inner Mongolians in China.

METHODS

A prospective cohort study from June 2003 to July 2012 was conducted among 2589 participants aged 20 years and older from Inner Mongolia, China. We categorized the participants into 4 subgroups according to the status of smoking and hypertension. The cumulative incidence rates of ischemic stroke among the 4 subgroups were estimated using Kaplan-Meier curves and compared by log-rank test. Cox proportional hazard model was used to compute hazard ratios of ischemic stroke across the 4 subgroups after adjusting for important confounding factors.

RESULTS

The cumulative incidence rates of ischemic stroke were .85%, 2.05%, 3.19%, and 8.14% among non-hypertension/non-smokers, non-hypertension/smokers, hypertension/non-smokers, and hypertension/smokers, respectively. The multivariable-adjusted hazard ratios [95% confidence intervals] of ischemic stroke for hypertension and smoking were 1.84 [1.05-3.23] and 1.89 [1.11-3.22], respectively. The hazard ratios [95% confidence intervals] of ischemic stroke for non-hypertension/smokers, hypertension/non-smokers, and hypertension/smokers were 1.37 [.56-3.33], 1.34 [.54-3.29], and 2.93 [1.26-6.83], respectively, compared with the non-hypertension/non-smokers. Significant interaction was detected between smoking and hypertension on the risk of ischemic stroke.

CONCLUSIONS

Our study indicated that participants with coexistence of smoking and hypertension were at the highest risk for ischemic stroke. There was a significant interaction between smoking and hypertension on the risk of ischemic stroke.

A population-based national estimate of the prevalence and risk factors associated with hypertension in Rwanda: implications for prevention and control

BACKGROUND

Hypertension is a leading cause of cardiovascular diseases and a growing public health problem in many developed and developing countries. However, population-based data to inform policy development are scarce in Rwanda. This nationally representative study aimed to determine population-based estimates of the prevalence and risk factors associated with hypertension in Rwanda.

METHODS

We conducted secondary epidemiological analysis of data collected from a cross-sectional population-based study to assess the risk factors for NCDs using the WHO STEPwise approach to Surveillance of non-communicable diseases (STEPS). Adjusted odds ratios at 95% confidence interval were used to establish association between hypertension, socio-demographic characteristics and health risk behaviors.

RESULTS

Of the 7116 study participants, 62.8% were females and 38.2% were males. The mean age of study participants was 35.3 years (SD 12.5). The overall prevalence of hypertension was 15.3% (16.4% for males and 14.4% for females). Twenty two percent of hypertensive participants were previously diagnosed. A logistic regression model revealed that age (AOR: 8.02, 95% CI: 5.63-11.42, p < 0.001), living in semi-urban area (AOR: 1.30, 95% CI: 1.01-1.67, p = 0.040) alcohol consumption (AOR: 1.24, 95% CI: 1.05-1.44, p = 0.009) and, raised BMI (AOR: 3.93, 95% CI: 2.54-6.08, p < 0.001) were significantly associated with hypertension. The risk of having hypertension was 2 times higher among obese respondents (AOR: 3.93, 95% CI: 2.54-6.08, p-value < 0.001) compared to those with normal BMI (AOR: 1.74, 95% CI: 1.30-2.32, p-value < 0.001). Females (AOR: 0.75, 95% CI: 0.63-0.88, p < 0.001) and students (AOR: 0.45, 95% CI: 0.25-0.80, p = 0.007) were less likely to be hypertensive.

CONCLUSION

The findings of this study indicate that the prevalence of hypertension is high in Rwanda, suggesting the need for prevention and control interventions aimed at decreasing the incidence taking into consideration the risk factors documented in this and other similar studies.

Awareness toward stroke in a population-based sample of Iranian adults

Background: Stroke is the leading cause of death and functional disability. While there have been major advances regarding the management of stroke, a significant proportion of people are still unaware of stroke-related symptoms and risk factors. This study was performed to assess the awareness of stroke's warning signs and risk factors among a sample of Iranian population. Methods: A total of 649 participants were randomly selected using systematic randomization from the list of telephone numbers obtained from the telephone directory. Demographic characteristics were recorded. Participants were asked to answer questions regarding the awareness about stroke, its warning signs and risk factors. Results: Patients' mean age was 32.0 ± 12.2 years old, and 56.4% were women. Hypertension and history of stroke were major risk factors, and loss of consciousness, vertigo and ataxia were major warning signs of stroke correctly identified by respondents. Multiple linear regressions showed that age (β = 0.277, P < 0.001), academic level of education (β = 6.41, P = 0.01), housewifery (β = 8.9, P < 0.001), jobs related to medical care (β = 13.17, P = 0.016) and previous information about stroke (β = 18.71, P < 0.001) were significant predictors of the overall awareness about stroke. Conclusion: The awareness of people about stroke, its risk factors and warning signs were good in this study. The awareness toward stroke can be associated with factors such as age, academic level of education, job and previous information about stroke. Further studies are recommended to program public multimedia and health education in academies and colleges.

Prevalence of intracranial artery stenosis in Iranian patients with acute ischemic stroke using transcranial Doppler ultrasonography

BACKGROUND

The aim of this study is to determine the frequency of intracranial artery stenosis in patients with acute ischemic stroke in Iran.

METHODS

A total of 169 patients with acute ischemic stroke were eligible to participate and were enrolled in this study from January 2012 to February 2013. All the patients were admitted to the Nemazee ‎Hospital, affiliated to Shiraz University of Medical Sciences, Iran. They underwent transcranial Doppler (TCD) ultrasonography. Mean flow velocity (MFV) of basilar artery, vertebral artery, middle cerebral artery (MCA), anterior cerebral artery (ACA), and posterior cerebral artery (PCA) were evaluated.

RESULTS

A mean of patients' age was 67.80 ± 8.14 years. There were 83 men (49.1%) and 86 women (50.9%). Overall, 43 patients (25.4%), with a mean age of 66.7 ± 6.2 years, had intracranial stenosis. The number of men and women with intracranial stenosis was comparable (52.4% men vs. 47.6% women). Hypertension (P < 0.001), hyperlipidemia (P < 0.001), and diabetes mellitus (DM) (P < 0.001) were major risk factors for intracranial stenosis.

CONCLUSION

The prevalence of intracranial artery stenosis in patients with acute ischemic stroke is 25.4% which is comparable with previous reports from Iran and other Middle East countries.

The epidemiology of stroke in the Middle East

Purpose

The purpose of this paper is to review and synthesize data from different countries in the Middle East on stroke and its potential risk factors.

Method

A systematic review of all published stroke articles in the Middle East between 1980 and May 2015 was conducted.

Findings

Sixty-four papers were included in the review. The incidence rate for all strokes ranged between 22.7 and 250 per 100,000 population per year. The prevalence rate for stroke ranged between 508 and 777 per 100,000 population. Among studies reporting gender differences, 75% reported a high male-to-female ratio among stroke patients. The mean age of stroke was within the sixth and the seventh decade. Ischemic stroke was the most reported type followed by intracerebral hemorrhage and subarachnoid hemorrhage. Hypertension was the most reported risk factor followed by diabetes. The overall case-fatality rate within one month was 12-32%.

Discussion

During the last decades, there was an increase in stroke incidence and mortality rates in the Middle East. The Middle East faces low rates of self-awareness and control of noncommunicable diseases and also lacks knowledge for stroke risk factors, awareness, causes, and symptoms.

Conclusion

There is an urgent need to develop more efficient and accurate methods to measure stroke in the Middle East. There is also a significant call to increase public awareness and implement interventions on stroke and its risk factors and symptoms to help people understand the negative impact of stroke on quality of life and potentially prevent this disease.

The relation between serum Vitamin D levels and body antioxidant status in ischemic stroke patients: A case-control study

BACKGROUND

Stroke is the second cause of death among elderly people. Oxidative stress plays an important role in brain damage after stroke. Currently, Vitamin D has been shown as an antioxidant. The aim of this study was to evaluate the status of Vitamin D, antioxidant enzymes, and the relation between them in ischemic stroke patients.

MATERIALS AND METHODS

This case-control study was carried out on 36 patients with ischemic stroke patients and 36 matched subjects as controls. Intake of fruits and vegetables, exposure of sunlight, serum lipid profile, concentrations of serum 25-dihydroxy Vitamin D (25(OH) D), activities of serum superoxide dismutase, and glutathione peroxidase enzymes were determined.

RESULTS

Severe Vitamin D deficiency was seen in 30% of the patients versus 11% of the controls (P < 0.05). Consumption of fruits and vegetables was lower in patients than that of controls (P < 0.05). Activities of antioxidant enzymes and intake of fruits were positively correlated in stroke patients (P = 0.02). The most potent predictors of stroke risk were hypertension, high levels of low-density lipoprotein cholesterol (LDL-C) and history of cardiovascular disease (CVD) (odds ratios: 3.33, 3.15, and 3.14, respectively, P < 0.05 for all). There was no association between 25(OH) D levels with activities of serum antioxidant enzymes and lipid profile in the two groups.

CONCLUSION

Ischemic stroke patients have higher prevalence of severe Vitamin D deficiency and lower intakes of fruits and vegetables. Intake of fruits was positive correlated to higher antioxidant enzymes levels. High levels of blood pressure, history of CVD, and high LDL-C levels are the strongest predictors of ischemic stroke.

Presence of hypertension modifies the impact of insulin resistance on incident cardiovascular disease in a Middle Eastern population: the Tehran Lipid and Glucose Study

AIMS

To examine the independent impacts of the homeostasis model assessment of insulin resistance (HOMA-IR) and the updated model (HOMA2-IR) on incident cardiovascular /coronary heart disease in a Middle Eastern population with a high prevalence of cardiovascular disease risk factors.

METHODS

We examined 3777 Iranian people, aged ≥ 30 years, without history of cardiovascular disease and without use of antidiabetic medication at baseline. Both HOMA-IR and HOMA2-IR were log-transformed and categorized into quartiles. The multivariable Cox proportional hazard regression model, adjusted for traditional cardiovascular disease risk factors, was applied to examine the association between HOMA-IR/HOMA2-IR with incident cardiovascular/coronary heart disease, considering the lowest quartile as reference.

RESULTS

During a median follow-up of > 10 years, 197 cardiovascular disease and 181 coronary heart disease events occurred. Among the covariates, we found a significant interaction between hypertension and HOMA-IR/HOMA2-IR for incident coronary heart/cardiovascular disease (all P ≤ 0.01). Among the population without hypertension, the risk of cardiovascular disease significantly increased in the second [hazard ratio 1.96 (95% CI 1.04-3.68)], third [hazard ratio 1.93 (95% CI 1.00-3.75)] and fourth [hazard ratio 2.34 (95% CI 1.15-4.75)] quartiles of HOMA-IR, and the risk of coronary heart disease increased significantly in the fourth quartile of HOMA-IR [hazard ratio 2.30 (95% CI 1.12-4.73)], but no significant association was detected between HOMA-IR and cardiovascular/coronary heart disease in the population with hypertension. Among the populations both with and without hypertension, no risk was found to be associated with HOMA2-IR quartiles however, a 1-unit increase in HOMA2-IR was associated with a significant risk of cardiovascular disease among the non-hypertensive group [hazard ratio 1.60 (95% CI 1.03-2.48); P = 0.03].

CONCLUSIONS

The presence of hypertension modified the impact of HOMA-IR/HOMA2-IR on incident cardiovascular/coronary heart disease. The presence of insulin resistance highlighted a significant and independent risk for cardiovascular disease/coronary heart disease only in the population without hypertension.

Presence and extent of coronary calcified plaque evaluated by coronary computed tomographic angiography are independent predictors of ischemic stroke in patients with suspected coronary artery disease

Although ischemic stroke and coronary artery disease (CAD) share common risk factors and pathophysiology, the risk of stroke in patients with CAD remains unclear. We sought to evaluate the risk of ischemic stroke in patients with suspected CAD according to coronary computed tomographic angiography (CCTA) and single-photon emission computed tomography (SPECT) findings. Presence, severity, and extent of CAD were evaluated in 1137 patients with suspected CAD who underwent CCTA and SPECT. Primary outcome was the occurrence of ischemic stroke. During follow-up (median 26 months), ischemic stroke was observed in 25 patients (2.2%). The presence of coronary plaque on CCTA was associated with the occurrence of ischemic stroke (2.8 vs. 0.6%; p = 0.029), while the presence of PD on SPECT was not (2.0 vs. 2.3%; p = 0.768). Stroke occurrence was not increased by the presence of significant stenosis of ≥50% DS (2.8%; p = 0.943), but was further increased by the plaque presence in ≥2 vessels (6.1 %; p = 0.001) or ≥3 segments (4.1%; p = 0.019). Presence of calcified plaque, and calcified plaque in ≥2 segments were also associated with ischemic stroke occurrence (4.3%; p < 0.001, and 5.6%; p < 0.001, respectively) and were the independent risk factors when adjusted to age of ≥65, hypertension, presence of any coronary plaque and plaque in ≥3 segments (adjusted HR 6.09; 95% CI 1.38-26.87; p = 0.017, and adjusted HR 5.47; 95% CI 1.85-16.19; p = 0.002, respectively). The risk of ischemic stroke was associated with the presence and extent of coronary atherosclerotic plaque evaluated by CCTA, but not with the presence and extent of myocardial ischemia evaluated by SPECT. Especially, calcified coronary plaque presence and extent were the independent predictors of ischemic stroke and allowed further risk stratification.

The interactive effect of diabetes and central obesity on stroke: a prospective cohort study of inner Mongolians

Background

The relationship between central obesity and stroke is inconsistent in diabetic and non-diabetic populations. This indicates an interaction between diabetes and central obesity on stroke risk. The present study aimed to examine the interaction in a cohort of Inner Mongolians.

Methods

In this prospective cohort study, we assessed the interaction between diabetes and central obesity on stroke incidence between June 2003 and July 2012. At baseline, 2,589 adults were recruited and examined from Inner Mongolia, China. Participants were categorized into four subgroups according to presence of diabetes and/or central obesity. Both additive and multiplicative interactions were evaluated using Cox proportional-hazard models.

Results

121 stroke events were recorded during the follow-up period. The cumulative incidence of stroke was highest for participants with both diabetes and central obesity (log-rank test, P = 0.042). The multivariable-adjusted risk for stroke was significantly higher in participants with both conditions (HR = 3.02, 95% CI 1.24-7.33, P = 0.015) compared to those with neither diabetes nor central obesity. Attributable proportion due to the interaction between diabetes and central obesity was 0.571 (95% CI 0.017-1.125). The multiplicative interactive effect between diabetes and central obesity on stroke was also statistically significant (HR = 2.67, 95% CI 1.14-6.26, P = 0.024).

Conclusions

The participants who were both diabetic and centrally obese had significantly higher risk for incident stroke than the combination of individuals who individually had either condition among Mongolian population. This study suggests that central obesity and diabetes act synergistically to increase the risk of stroke.

Cardiovascular disease mortality and years of life lost attributable to non-optimal systolic blood pressure and hypertension in northeastern Iran

BACKGROUND

High blood pressure is the second most important risk factor of cardiovascular diseases (CVDs) in Iran. It is imperative to estimate the burden of CVDs that can be averted if high blood pressure is controlled at the population level. The aim of the current study was to estimate the avertable CVD mortality in the setting of Golestan Cohort Study (GCS).

METHODS

Over 50,000 participants were recruited and followed for a median of 7 years. The exposures of interest in this study were non-optimal systolic blood pressure (SBP) and hypertension measured at baseline. Deaths by cause have been precisely recorded. The Population Attributable Fraction (PAF) of deaths and Years of Life Lost (YLLs) due to CVDs attributable to exposures of interest were calculated.

RESULTS

Overall, 223 deaths due to ischemic heart disease (IHD), 207 deaths due to cerebrovascular accidents (CVA), and 460 deaths due to all CVDs could be averted if the SBP of all subjects in the study were optimal. Similarly, 5,560 YLLs due to IHD, 4,771 YLLs due to CVA, and 11,135 YLLs due to CVDs could be prevented if SBP were optimal. In all age groups, the avertable deaths and YLLs were higher due to IHD compared with CVA. Deaths and YLLs attributable to non-optimal SBP in women were less than men.

CONCLUSIONS

A very large proportion of CVD deaths can be averted if blood pressure is controlled in Iran. Effective interventions in primary and secondary health care setting are mandatory to be implemented as early as possible.

Estimating the potential impact fraction of hypertension as the main risk factor of stroke: Application of the distribution shift method

Few published studies have assessed the impact of quantitative risk factors such as high blood pressure on stroke. The aim of this study was to quantify the potential impact fraction (PIF) of hypertension on stroke in Hamadan Province, western Iran. Avoidable burden of stroke associated with high blood pressure was calculated using distribution shift at different scenarios. Data on the prevalence of high blood pressure among residents of Hamadan province older than 19 years were extracted from non-communicable diseases risk factors surveillance system in 2009. Five mmHg hypothetical reduction in systolic blood pressure above 140 mmHg, leads to 3.5% (PIF=0.035) reduction in the total burden to stroke. This value may reach 7%, if systolic blood pressure decreases 10 mmHg. In addition, 5 mmHg hypothetical reduction in diastolic blood pressure above 82 mmHg, leads to 4.87% reduction in the total burden to stroke. PIF more than 10 mmHg modification on distribution of diastolic blood pressure was estimated as 9.38%. According to these findings, policy makers are advised to implement interventions on hypertension based on the distribution shift method rather than the proportion shift one.

Hypertension, alcohol drinking and stroke incidence: a population-based prospective cohort study among inner Mongolians in China

OBJECTIVES

The purpose of this study was to evaluate the effect of hypertension and alcohol drinking on stroke incidence and whether alcohol drinking would increase the risk of stroke in hypertension participants among Inner Mongolians.

METHODS

A prospective cohort study from June 2003 to July 2012 was conducted among 2535 people aged 20 years and older from Inner Mongolia, China. We categorized the participants into four subgroups according to blood pressure and drinking status. The cumulative risks of stroke among the four subgroups were estimated with the Kaplan-Meier curves and compared by log-rank test. Cox proportional hazards models and receiver operating characteristic (ROC) curves were employed to evaluate the association between hypertension, alcohol drinking and stroke incidence.

RESULTS

A total of 120 stroke patients were observed during the follow-up period. The multivariate-adjusted hazard ratios (95% confidential intervals) of stroke for nonhypertension/drinkers, hypertension/nondrinkers and hypertension/drinkers were 1.03 (0.48-2.22), 2.64 (1.45-4.81) and 2.89 (1.55-5.39), respectively, compared with nonhypertension/nondrinkers. The area under ROC curve (AUC) for a model containing hypertension and drinking status along with conventional factors (AUC = 0.684) was significantly (P = 0.005) larger than one containing only conventional factors (AUC = 0.660).

CONCLUSION

These findings suggest that hypertension is an independent risk factor of stroke in Inner Mongolians. Drinkers with hypertension seem to be more susceptible to stroke; larger-sample prospective cohort studies are still required to examine the cumulative effect of drinking and hypertension on stroke incidence.

Candesartan and glycyrrhizin ameliorate ischemic brain damage through downregulation of the TLR signaling cascade

Stroke is the second leading cause of death in industrialized countries and the most frequent cause of permanent disability in adults worldwide. The final outcome of stroke is determined not only by the volume of the ischemic core, but also by the extent of secondary brain damage inflicted to penumbral tissues by brain swelling, impaired microcirculation, and inflammation. The only drug approved for the treatment ischemic stroke is recombinant tissue plasminogen activator (rt-PA). The current study was designed to investigate the protective effects of candesartan (0.15 mg/kg, orally) and glycyrrhizin (30 mg/kg, orally) experimentally-induced ischemic brain damage in C57BL/6 mice (middle cerebral artery occlusion, MCAO) in comparison to the effects of a standard neuroprotective drug (cerebrolysin, 7.5 mg/kg, IP). All drugs were administered 30 min before and 24h after MCAO. Both candesartan and glycyrrhizin ameliorated the deleterious effects of MCAO as indicated by the improvement in the performance of the animals in behaviour tests, reduction in brain infarction, neuronal degeneration, and leukocyte infiltration. In addition, MCAO induced a significant upregulation in the different elements of the TLR pathway including TLR-2 and TLR-4, Myd88, TRIF and IRF-3 and the downstream effectors TNF-α, IL-1β, IL-6 and NF-kB. All these changes were significantly ameliorated by treatment with candesartan and glycyrrhizin. The results of the current study represent a new indication for both candesartan and glycyrrhizin in the management of ischemic stroke with effects comparable to those of the standard neuroprotective drug cerebrolysin.