Weight fluctuation, mortality, and cardiovascular disease in adults in 18 years of follow-up: Tehran Lipid and Glucose Study

PURPOSE

Controversies exist in the effect of body weight loss and fluctuation on cardiovascular disease (CVD) and mortality. This study aims to assess the effect of weight variability on CVD and all-cause and cardiovascular mortality in the Tehran Lipid and Glucose Study (TLGS) cohort.

METHOD

Participants aged  ≥ 40 year at the baseline period with at least 3 BMI measurements were included in this study. After excluding individuals with cancer, CVD, end-stage renal disease, systemic use of glucocorticoids, pregnancy, and missing covariates at the baseline, a total of 3461 participants were enrolled and followed for 18 years. BMI variability was defined using root mean squared error (RMSE) and average successive variability (ASV). In the RMSE method, BMI variability was calculated using the best-fitting model for BMI trend of each subject. Multivariate Cox proportional hazard models were applied to assess BMI variability's effect on CVD and mortality.

RESULTS

Among the 3461 participants in this study, the group with the highest weight variability had an increased risk of death for all-cause (HR 1.65; 95% CI 1.21-2.25), non-cardiovascular (HR 1.77; 95% CI 1.24-2.53), and non-cancer (HR 1.77; 95% CI 1.25-2.50) mortality. However, BMI variability showed to be protective against CVD (HR 0.76; 95% CI 0.6-0.97). These findings were significant in males, non-smokers, participants with age  ≤ 60 year, BMI < 30, negative BMI slope, and both diabetic and non-diabetic subjects.

CONCLUSION

High BMI variability is associated with increased risk of all-cause, non-CVD, and non-cancer mortality, although protective for the CVD event. Appropriate strategies for body weight maintenance after weight loss could be adopted to avoid weight variability, particularly in non-obese subjects.

Pre-diabetes tsunami: incidence rates and risk factors of pre-diabetes and its different phenotypes over 9 years of follow-up

AIMS

To investigate the incidence of pre-diabetes and its different phenotypes and the related risk factors during 9 years of follow-up.

METHODS

A total of 5879 people (2597 men and 3282 women) aged ≥ 20 years, free of diabetes and pre-diabetes, took part in the study. Multivariable Cox proportional hazard models were used to evaluate hazard ratios (HR) and 95% confidence intervals (CI) for all potential risk factors.

RESULTS

Overall, 853 men and 902 women developed pre-diabetes. Incidence rates of pre-diabetes were 46.1 per 1000 person-years in men and 36.8 per 1000 person-years in women, while isolated impaired fasting glucose had the highest incidence rate among all pre-diabetes phenotypes. In both sexes, age, family history of diabetes, fasting plasma glucose and 2-hour post-challenge plasma glucose were related to incident pre-diabetes. Among women, waist-to-height ratio [HR: 1.02 (1.00-1.03)] and being divorced/widowed compared with married [HR: 0.67 (0.52-0.87)] were significant predictors of pre-diabetes; whereas among men, community-based intervention [HR: 0.79 (0.68-0.90)], higher level of education and being single [HR: 0.77 (0.6-0.97)] were protective against progression to pre-diabetes. Moreover, hip circumference among women [HR: 0.95 (0.93-0.98)] and current smoking among men [HR: 1.69 (1.15-2.48)] were related to incident combined impaired fasting glucose and impaired glucose tolerance.

CONCLUSION

More than 4% of the Iranian population develop pre-diabetes each year, emphasizing the important role of socio-economic factors (marital status, education and smoking habits) and community-based intervention in progression to impaired glucose regulations. Thus, emergent intervention is necessary to halt the tsunami of pre-diabetes among the Iranian population.

The effect of a single dose of vitamin D on glycemic status and C-reactive protein levels in type 2 diabetic patients with ischemic heart disease: a randomized clinical trial

AIMS

To assess whether a single parental dose of 25-hydroxy vitamin D [25(OH)Vit D] could improve glucose control and inflammation in type 2 diabetic patients (T2D) with ischemic heart disease (IHD).

METHODS

A randomized, placebo-controlled, double-blind trial was performed on 95 patients (47-placebo and 48-vitamin D groups). Participants were randomized using a randomization table to a single dose of either vitamin D (300,000 IU, IM) or a matching placebo. Fasting blood sugar (FBS), glycosylated hemoglobin (HbA1c), 25(OH)Vit D and high-sensitivity C-reactive protein (hs-CRP) were measured at baseline and at 8 weeks.

RESULTS

No significant differences in baseline values were noted between groups, except in HbA1c, which was lower in the placebo group. In the supplemented group, the level of serum 25(OH)Vit D increased (29.6 ± 20.8 vs. 44.5 ± 19.2 ng/mL) and those of FBS and HbA1c decreased significantly [186.5 ± 64.1 vs. 165.1 ± 58.5 mg/dL and 8.2 ± 2.0 % (66.3 ± 21.8 mmol/mol) vs. 7.7 ± 1.8 % (61.7 ± 20.0 mmol/mol), respectively] (all p < 0.05), and no changes, however, were observed in the placebo group. We also compared change of marginal means of outcome variables (HbA1c, FBS, 25(OH)Vit D and hs-CRP) from baseline between the vitamin D versus placebo group, using ANCOVA, adjusted for the baseline of each variable itself, season at study entry, age and body mass index. During trial, only HbA1c level decreased significantly [0.48 % (standard error: 0.17), p = 0.04]. No any adverse effect was seen.

CONCLUSIONS

A single parenteral dose of vitamin D in T2D patients with IHD improved glycemic control, but not inflammatory status.

CLINICAL TRIAL REGISTRY

Australian New Zealand Clinical Trial Registry.

CLINICAL TRIAL NUMBER

ACTRN12614000529640.

Women self-perception of excess hair growth, as a predictor of clinical hirsutism: a population-based study

PURPOSE

Hirsutism is the most common indicator of hyperandrogenism. Both, the sensitivity of the patients to the serum androgen levels and the responsiveness of women to the perceived excess hair growth vary among different populations. This report elaborates the relationship between the woman's discerned abnormal hair growths with the clinical diagnosis of hirsutism.

METHODS

The survey was conducted among 1160 women aged 18-45 and randomly selected from Tehran Lipid and Glucose Study for further detailed assessment of Hirsutism; using the m-FG scoring method. Data gathering was performed by interviews and physical examinations. The receiver operating characteristic curve was drawn and the new cutoff value, sensitivity, specificity and concordance percentage were calculated.

RESULTS

The results demonstrated that among 12 androgen-dependent body areas, the chin skin had the highest area under curve of 0.81 (CI; 0.78-0.84). According to the patient's evaluation, a threshold point of 4 had the optimum concordance percentage of 0.77 with the modified Ferriman-Gallwey scoring system.

CONCLUSIONS

Patient's self-identification of excess terminal hair based on the chin area has great sensitivity and reliability in predicting the clinical hirsutism.

Relationship of hyperinsulinaemia, insulin resistance and β-cell dysfunction with incident diabetes and pre-diabetes: the Tehran Lipid and Glucose Study

AIMS

To examine the association of fasting insulin, insulin resistance and reduced β-cell function with incident Type 2 diabetes and pre-diabetes (isolated impaired fasting glucose/isolated impaired glucose tolerance and combined impaired fasting glucose/impaired glucose tolerance).

METHODS

An Iranian population comprising 1532 men and 2221 women, aged ≥ 20 years, with normal fasting glucose and normal glucose tolerance at baseline, were enrolled in the study. Multivariable Cox proportional hazard models were used to calculate the hazard ratios and 95% CIs of fasting insulin, updated homeostasis model assessments of insulin resistance and β-cell function for incident Type 2 diabetes, isolated impaired fasting glucose, isolated impaired glucose tolerance and combined impaired fasting glucose/impaired glucose tolerance.

RESULTS

During a median follow-up of 9.2 years, the annual incidence rates (95% CI) of diabetes were 3.73 (2.74-4.94) and 4.06 (3.21-5.06) per 1000 person-years in men and women, respectively. In both men and women, fasting insulin and homeostasis model assessment of insulin resistance (≥ 75th percentile) were significantly associated with incident diabetes and combined impaired fasting glucose/impaired glucose tolerance; however, reduced β-cell function as measured by homeostasis model assessment of β-cell function (< 25th percentile) was associated with incident isolated impaired fasting glucose solely in men [hazard ratio 1.35 (95% CI 1.02-1.78)] in multivariable analysis including waist-hip ratio). Hyperinsulinaemia, insulin resistance and β-cell dysfunction were not related to the incidence of isolated impaired glucose tolerance in either gender.

CONCLUSIONS

Fasting hyperinsulinaemia and insulin resistance were strong risk factors for progression to diabetes and combined impaired fasting glucose/impaired glucose tolerance in a population with normal fasting glucose/normal glucose tolerance. In addition, impaired β-cell function at baseline was related to the development of isolated impaired fasting glucose only in men and, in both men and women, neither insulin resistance nor β-cell dysfunction were associated with incident isolated impaired glucose tolerance.

Does metabolic syndrome or its components differ in naturally and surgically menopausal women?

OBJECTIVES

This study aimed to compare metabolic syndrome and its components in naturally and surgically menopausal women.

METHODS

This is a longitudinal study, with incident case and control groups, conducted on 446 women participants of the Tehran Lipid and Glucose Study, who experienced surgical or natural menopause over a 10-year period. In both groups, data collection was conducted using questionnaires including information on demographic, reproductive and metabolic characteristics at baseline and again after 3 years. Physical examinations and the biochemical profiles were also assessed.

RESULTS

During the follow-up, metabolic syndrome was observed in 28.7% and 32.5% of the naturally menopause and surgically menopausal women, respectively. Mean fasting blood sugar and 2-h plasma glucose were significantly higher in the surgically menopause group, compared to the naturally menopause one, whereas mean systolic blood pressure was significantly higher in naturally menopausal women as compared to surgically menopause ones, after further adjustment for premenopausal status.

CONCLUSIONS

Although no difference in the prevalence of metabolic syndrome in naturally menopausal women and in surgically menopausal women was found, the components of metabolic syndrome were more prevalent among those with surgical menopause.

Non-linear association between 25-hydroxyvitamin D and the incidence of type 2 diabetes: a community-based nested case-control study

AIMS

To examine the nature of the association between 25-hydroxyvitamin D [25(OH)D] and newly diagnosed type 2 diabetes.

METHODS

Serum 25(OH)D concentrations were measured for 761 participants (aged 20-83 years) in the Tehran Lipid and Glucose Study, selected for a 1-to-3 nested case-control study. Cases were 191 cases of Type 2 diabetes diagnosed during a median follow-up of 3.6 years. A total of 570 participants were matched with these cases with regard to age, sex, BMI, and month of entering the study. Diabetes was defined according to the American Diabetes Association criteria, 2003. Serum 25(OH)D was measured using the enzyme immunoassay method. Odds ratios for Type 2 diabetes were obtained from conditional logistic regression models for tertiles of serum 25(OH)D concentrations [tertile-1: 2.82-11.02 (reference), tertile-2: 11.03-21.80, and tertile-3: ≥ 21.82 ng/ml]. The multivariate model was adjusted for age, sex, family history of diabetes, systolic blood pressure, triglyceride-to- HDL cholesterol ratio, waist-to-height ratio, lifestyle modification intervention, leisure time physical activity, and fasting plasma glucose at baseline. Non-linearity in the associations between baseline 25(OH)D and Type 2 diabetes, was examined by using restricted cubic splines.

RESULTS

Unadjusted odds ratios (95% confidence intervals) of diabetes were 0.73 (0.74-1.13), 0.54 (0.34-0.85) for the second and third tertiles, respectively. Multivariate adjusted odds ratios were 0.47 (0.25-0.90) and 0.43 (0.23-0.82), respectively. Below the cutoff of ~ 10 ng/ml the risk of newly diagnosed Type 2 diabetes increased dramatically.

DISCUSSION

It was found that 25(OH)D concentrations contributed to the Type 2 diabetes incidence rate in a non-linear fashion, with the risk beginning to increase sharply for values < 10 ng/ml.

Estimating the proportion of diabetes to the attributable burden of cardiovascular diseases in iran

BACKGROUND

This study aimed at estimating the proportion of diabetes as a risk factor to the attributable burden of cardiovascular diseases in Iran.

METHODS

Comparative Risk Assessment methodology was used to calculating Potential Impact Fraction (PIF). To calculate PIF, data on the prevalence of newly diagnosed diabetes mellitus (NDM) and known diabetes mellitus (KDM) were obtained from 3rd Iranian surveillance of risk factors of non-communicable diseases and data on corresponding measures of effect were derived from a cohort study. PIF were estimated on both theoretical minimum and feasible minimum risk. Uncertainty for the attributable burden was estimated by Monte Carlo simulation-modeling techniques incorporating sources of uncertainty.

RESULTS

According to multivariate-adjusted hazard ratios, by reducing the prevalence of Iranian women with diabetes from 10.05 percent to the feasible minimum risk level i.e. 5 percent, 6.8% (95% uncertainty intervals: 3.5-9.8) of attributable Disability Adjusted Life Years (DALYs) to CVD are avoidable and the corresponding value for men were 3.1% (95% uncertainty intervals: 1.4-4.8).

CONCLUSION

Although data on the prevalence of diabetes and corresponding measures of associations were obtained from an updated and country-specific source, but to better priority setting, PIF should be applied to updated and revised burden of CVDs.

A new approach to compare the predictive power of metabolic syndrome defined by a joint interim statement versus its components for incident cardiovascular disease in Middle East Caucasian residents in Tehran

BACKGROUND

Metabolic syndrome (MS) has an increased risk for developing cardiovascular disease (CVD); however, whether the concept of MS, applying the new joint interim statement definition, has a greater impact on incident CVD than its individual components is debated.

METHODS

The authors related MS and its components to CVD incidence in 1856 men and 2392 women, Iranian adults aged ≥40 years, free of CVD at baseline, using Cox proportional hazards models. To examine whether MS would improve prediction of CVD beyond that achieved by its components; model fitness, discrimination and integrated discrimination improvement (IDI) statistics were used.

RESULTS

During a median follow-up of 8.6 years, there were 244 CVD events in men and 189 in women. MS resulted in HRs (95% CIs) of 1.97 (1.50 to 2.57) in men and 2.25 (1.57 to 3.21) in women after adjusting for CVD risk factors; in another model including all the five MS components, high blood pressure in both genders [men: 1.99 (1.48 to 2.67), women: 1.62 (1.14 to 2.30)), high waist circumference (≥94.5 cm) in men (1.47 (1.12 to 1.93)) and high fasting plasma glucose (FPG) in women (1.88 (1.39 to 2.55)) remained as independent predictors of CVD after adjusting for CVD risk factors. Adding the MS variable to this model did not yield any improvement in model fitness, C-statistic or significant IDI value.

CONCLUSION

In the Middle East population, MS did not provide CVD predictive risk information beyond its individual components; clinical focus should remain on hypertension in both sexes, high FPG in women and central adiposity in men rather than MS.

Glucose intolerance and risk of cardiovascular disease in Iranian men and women: results of the 7.6-year follow-up of the Tehran Lipid and Glucose Study (TLGS)

BACKGROUND

Despite the high prevalence of diabetes, limited information is available about the impact of impaired glucose regulation on the cardiovascular disease (CVD) risk among Middle East populations.

AIMS

To determine the risk of CVD in an urban Iranian population according to glucose tolerance status.

MATERIALS AND METHODS

The study population consisted of 1752 men and 2273 women, aged > or = 40 yr, free of CVD at baseline. Incident CVD was ascertained over a median of 7.6 yr of follow-up.

RESULTS

A total of 340 CVD events occurred (197 in men and 143 in women). At baseline, there was no difference between newly diagnosed and known diabetes regarding the Prospective Cardiovascular Münster (PROCAM) risk score and prevalence of metabolic syndrome in both genders. Applying the 1997 American Diabetes Association (ADA) criteria, compared with those with normal glucose tolerance, after controlling traditional risk factors, hazard ratios (HR) and 95% confidence intervals (95% CI) for CVD in women with known and newly diagnosed diabetes were 3.30 (2.09-5.21) and 1.93 (1.16-3.21) and the corresponding values for men were 1.90 (1.11-3.25) and 1.69 (1.12-2.54), respectively. Impaired fasting glucose or impaired glucose tolerance was associated with 56% increased risk of CVD in women (HR 1.56, 95% CI 1.00 to 2.45), in the age-adjusted analysis, considering the 2003 ADA criteria.

CONCLUSIONS

All diabetic subjects, whether newly diagnosed or known cases, should receive intensive primary prevention for CVD regardless of risk factors, in particular females with abnormal glucose regulation.

Triglyceride/HDL-cholesterol ratio is an independent predictor for coronary heart disease in a population of Iranian men

BACKGROUND AND AIMS

To determine whether triglyceride/high-density lipoprotein cholesterol ratio (TG/HDL-C), which has been shown to be an indicator of the metabolic syndrome (MetS) and insulin resistance, can predict coronary heart disease (CHD) independently of total cholesterol (TC) and other risk factors in an Iranian population with a high prevalence of MetS and low HDL-C.

METHODS AND RESULTS

Between February 1999 and August 2001, 1824 men > or =40 years old, free of clinical cardiovascular diseases at baseline, were followed. Baseline measurements included serum level of TC, HDL-C, TG and risk factors for CHD including age, systolic and diastolic blood pressure, body mass index, waist circumference, diabetes, smoking and a family history of premature cardiovascular diseases. During a median follow up of 6.5 years until March 2007 (11,316 person-years at risk), a total of 163 new CHD events (27 fatal and 136 nonfatal) occurred. The prevalence of MetS in subjects with TG/HDL-C > or =6.9 (top quartile) reached 63.6% versus 3.0% in those with TG/HDL-C <2.8 (low quartile). According to a stepwise Cox proportional hazard model, including TG and TG/HDL-C quartiles, with TC and other risk factors, men in the top quartile of TG/HDL-C relative to the first quartile had a significant hazard ratio (HR) of 1.75 (95% CI, 1.02-3.00), while TG did not remain in the model.

CONCLUSION

The evaluation of TG/HDL-C ratio should be considered for CHD risk prediction in our male population with a high prevalence of MetS.

Synthesis of some new bis-Schiff bases of isatin and 5-fluoroisatin in a water suspension medium

Condensation of aromatic primary bis-amines with isatin (1H-indole-2,3-dione) and 5-flouroisatin occurred cleanly and efficiently in a water suspension medium without using any organic solvent or acid catalyst. The corresponding bis-Schiff bases were obtained in good yields and were easily isolated by filtration. Their structures were confirmed by (1)H-NMR, (13)C-NMR, IR and mass spectra.