Lipid accumulation product and insulin resistance in Iranian PCOS prevalence study

Association of visceral adiposity index and lipid accumulation products with prediabetes in US adults from NHANES 2007-2020: A cross-sectional study

BACKGROUND

The lipid accumulation product (LAP) and the visceral adiposity index (VAI) are suggested as dependable measures for assessing visceral fat levels. Prediabetes is recognized as a condition that precedes the potential onset of diabetes. The objective of this research is to investigate how VAI and LAP are related to prediabetes among the adult population in the United States.

METHODS

Information from the 2007-2020 National Health and Nutrition Examination Survey (NHANES) was scrutinized in a cross-sectional study. To evaluate the connection between VAI or LAP and the presence of prediabetes, both univariate analysis and multivariate logistic regression were utilized. Threshold effect analysis and fitted smoothing curves were used to delve into the non-linear association between VAI or LAP and prediabetes. Additional analyses were performed on specific subgroups, along with tests to explore potential interactions.

RESULTS

In general, 12,564 American adults were included. After full adjustment, prediabetes with VAI (OR: 1.128, 95% CI: 1.073-1.185) or LAP (OR: 1.006, 95% CI: 1.004-1.008) showed a positive correlation. Individuals in the 4th VAI quartile group faced a significant 61.9% elevated risk for prediabetes (OR: 1.619, 95% CI: 1.354-1.937) when contrasted to those in the 1st VAI quartile. Participants in the 4th LAP quartile group had a significant 116.4% elevated risk for prediabetes (OR: 2.164, 95% CI: 1.747-2.681) when contrasted to individuals of the 1st LAP quartile. Smooth curve fitting analysis revealed a nonlinear correlation of VAI or LAP and prediabetes, and threshold effect analysis was used to determine an inflection point of 4.090 for VAI and 68.168 for LAP.

CONCLUSIONS

The values of VAI and LAP are positively associated with the prevalence of prediabetes. The VAI and LAP indices may be used as predictors of prediabetes.

Lipid accumulation product and visceral adiposity index: two indices to predict metabolic syndrome and insulin resistance in chronic kidney disease patients

Objective. Chronic kidney disease (CKD), metabolic syndrome (MetS) and insulin resistance (IR) are the major health problems associated with the increasing risk of cardiovascular and cerebrovascular complications. Methods. This cross-sectional study included 209 CKD patients of stage (3-5) on conservative treatment to assess the usage of lipid accumulation product (LAP) and visceral adiposity index (VAI) to predict both MetS and IR in CKD patients. Results. In males, from the anthropometric measurements, LAP was the best predictor of MetS with 94.4% sensitivity and 77.8% specificity. VAI was the next one with 83.3% sensitivity and 69.4% specificity. The same results were obtained in females. The receiver operating characteristic (ROC) curve showed LAP as the best predictor of MetS with the highest 92.6% sensitivity and 60.6% specificity followed by VAI with 83.6% sensitivity and 83.6% specificity. In addition, LAP was a good predictor of IR with more than 70% sensitivity in both males and females. VAI as a predictor of IR showed 62.2% sensitivity in males and 69.9% in females. Conclusion. The present data indicate that both LAP and VAI can serve as predictors of MetS and IR in CKD patients, whereas LAP is the best anthropometric measure to predict MetS and LAP is more sensitive and specific than VAI in IR predicting in both males and females.

Lipid ratios and obesity indices are effective predictors of metabolic syndrome in women with polycystic ovary syndrome

BACKGROUND

Insulin resistance (IR) is common in women with polycystic ovary syndrome (PCOS). Metabolic syndrome (MS) involves IR, arterial hypertension, dyslipidemia, and visceral fat accumulation. Therefore, fatness indices and blood lipid ratios can be considered as screening markers for MS. Our study aimed to evaluate the predictive potential of selected indirect metabolic risk parameters to identify MS in PCOS.

METHODS

This cross-sectional study involved 596 women aged 18-40 years, including 404 PCOS patients diagnosed according to the Rotterdam criteria and 192 eumenorrheic controls (CON). Anthropometric and blood pressure measurements were taken, and blood samples were collected to assess glucose metabolism, lipid parameters, and selected hormone levels. Body mass index (BMI), waist-to-height ratio (WHtR), homeostasis model assessment for insulin resistance index (HOMA-IR), visceral adiposity index (VAI), lipid accumulation product (LAP), non-high-density lipoprotein cholesterol (non-HDL-C), and triglycerides-to-HDL cholesterol ratio (TG/HDL-C) were calculated. MS was assessed using the International Diabetes Federation (IDF) and the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) criteria.

RESULTS

MS prevalence was significantly higher in PCOS versus CON. Patients with both MS and PCOS had more unfavorable anthropometric, hormonal, and metabolic profiles versus those with neither MS nor PCOS and versus CON with MS. LAP, TG/HDL-C, VAI, and WHtR were the best markers and strongest indicators of MS in PCOS, and their cut-off values could be useful for early MS detection. MS risk in PCOS increased with elevated levels of these markers and was the highest when TG/HDL-C was used.

CONCLUSIONS

LAP, TG/HDL-C, VAI, and WHtR are representative markers for MS assessment in PCOS. Their predictive power makes them excellent screening tools for internists and enables acquiring accurate diagnoses using fewer MS markers.

Effect of l-carnitine supplementation on liver fat content and cardiometabolic indices in overweight/obese women with polycystic ovary syndrome: A randomized controlled trial

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder among reproductive-age women, and is associated with cardiovascular diseases as well as non-alcoholic fatty liver disease. The recent evidence suggested the beneficial effects of l-carnitine in women with PCOS.

OBJECTIVE

The present study aimed to investigate the effect of l-carnitine supplementation on liver fat content and cardiometabolic outcomes in overweight/obese women with PCOS.

METHODS

The present study was designed as a 12-week double-blind, randomized controlled clinical trial. Sixty-two overweight/obese women with PCOS were assigned into the treatment (received 1000 mg/d l-carnitine capsule) and the control (received placebo capsule) groups. The outcomes included lipid accumulation product (LAP), atherogenic index of plasma (AIP), atherogenic coefficient (AC) and Castelli II indices.

RESULTS

At the end of the trial, there was no significant difference between the treatment and the control groups in terms of LAP (-1.1 vs. -4.0; P = 0.45), AIP (0.0 vs. -0.09; P = 0.14), AC (-0.2 vs. -0.8; P = 0.06) and Castelli II index (-0.2 vs. -0.6; P = 0.07) after controlling the mean change of waist circumference.

CONCLUSION

l-carnitine supplementation for 12 weeks has no beneficial effect on liver fat content and cardiometabolic outcomes in overweight or obese women with PCOS.

TRIAL REGISTRATION

Registered on 30 December 2019 at Iranian Registry of Clinical Trials IRCT20191016045131N1.

Effect of omega-3 supplementation on fatty liver and visceral adiposity indices in diabetic patients with non-alcoholic fatty liver disease: A randomized controlled trial

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) as the most common chronic liver disease is closely linked to type 2 diabetes mellitus (T2DM). Omega-3 supplementation has been proposed as a strategy to manage T2DM and NAFLD. The present study aimed to investigate the effect of omega-3 supplementation on fatty liver index, lipid accumulation product and visceral adiposity index in diabetic patients with NAFLD.

METHODS

In this 12-week double-blind, randomized controlled clinical trial, sixty diabetic patients with NAFLD were randomly assigned into the omega-3 and placebo groups for 12 weeks. The omega-3 group received 2000 mg/d omega-3 as capsule.

RESULTS

Fifty-six participants completed the study. No significant difference was found between the two groups in the terms of fatty liver index, lipid accumulation product and visceral adiposity index at the baseline. Omega-3 supplementation compared with the placebo led to a significant improvement in fatty liver index (-3.6 ± 12.1 vs. 0.9 ± 8.9; P = 0.04), lipid accumulation product (-14.2 ± 27.9 vs. 8.0 ± 26.3; P = 0.002) and visceral adiposity index (-0.5 ± 0.9 vs. 0.0 ± 0.8; P = 0.01).

CONCLUSION

Omega-3 supplementation for 12 weeks improves fatty liver index, lipid accumulation product and visceral adiposity index. The study protocol was registered under Iranian Registry of Clinical Trials identifier number IRCT2016102530489N1.

Body Fat Indices as Effective Predictors of Insulin Resistance in Obstructive Sleep Apnea: Evidence from a Cross-Sectional and Longitudinal Study : BFI as Predictors of IR in OSA

PURPOSE

Body fat indices serve as predictive markers of insulin resistance (IR) in metabolic diseases. IR is common in obstructive sleep apnea (OSA). However, whether body fat indices have utility as predictors of IR in OSA remain unknown.

MATERIALS AND METHODS

A longitudinal study was conducted in 46 patients undergoing bariatric surgery to explore the relationship between IR and body fat indices. Then, a cross-sectional study was performed to evaluate the relationships between body fat indices and IR, and receiver operating characteristic (ROC) curves were generated. Body indices, homeostasis model assessment index of insulin resistance (HOMA-IR), biological indicators, and polysomnographic variables were collected.

RESULTS

In the longitudinal study, significant relationships were found between remission of IR and changes in visceral adiposity index (VAI) (r = 0.452, P < 0.05) and triglyceride-glucose index (TyG) (r = 0.650, P < 0.01). In the cross-sectional study, lipid accumulation product (LAP) (best cutoff value: 30.16, area under the curve (AUC) = 0.728, P < 0.001) and TyG (best cutoff value: 8.54, AUC = 0.740, P < 0.001) were indicators of IR in normal weight group. In overweight/obese group, body mass index (BMI) (best cutoff value: 27.69 AUC = 0.707, P < 0.001) and waist circumference (WC) (best cutoff value: 97.25, AUC = 0.708, P < 0.001) were markers of IR. TyG showed better ability to predict IR in normal weight females (best cutoff value: 8.39 AUC = 0.813, P < 0.001).

CONCLUSIONS

Body fat indices are predictive markers of IR in patients with OSA.

Lipid accumulation product independently correlate with hepatic steatosis quantified by controlled attenuation parameter in women with polycystic ovary syndrome

OBJECTIVE

To explore the independent associations of the new adiposity indices lipid accumulation product (LAP) index, visceral adiposity index (VAI), and product of triglycerides and glucose (TyG) with the risks of hepatic steatosis (HS) in women with polycystic ovary syndrome (PCOS).

DESIGN

This is a cross-sectional study with 101 women with PCOS undergoing controlled attenuation parameter (CAP) measurement who were recruited from November 2018 to August 2019. Multivariable logistic regression analysis was performed to determine the associations of adiposity indices with HS.

RESULT(S)

Among the 101 PCOS patients, the prevalence rate of HS was 70.3%. The PCOS patients with HS have higher percentage of overweight/obesity status, higher level of aminotransferase (AST and ALT), homeostasis model assessment of insulin resistance (HOMA-IR), LAP, VAI, TyG, waist circumference (WC), and BMI (P < 0.05). Partial correlation analysis showed LAP, WC and BMI were significantly positively associated with CAP (P < 0.05) after controlling for confounding factors. Besides, BMI, WC, and CAP were gradually elevated with the increase of LAP level. Further, multivariable logistic regression analysis showed adjusted odd ratio (OR) with associated 95% CI (OR (95% CI)) were respectively 1.09 (1.03-1.16) for LAP, 1.14 (1.05-1.23) for WC, 1.28 (1.08-1.51) for BMI, respectively.

CONCLUSIONS

The present study demonstrates that in women with PCOS, except for the traditional adiposity indices (WC and BMI), LAP is independently correlated with the risk of HS.

Overtime trend of thyroid hormones and thyroid autoimmunity and ovarian reserve: a longitudinal population study with a 12-year follow up

BACKGROUND

Ovarian reserve, vital for reproductive function, can be adversely affected by thyroid diseases. Despite alternations of thyroid hormones with ageing, data on interactions between the overtime trend of thyroid functions and ovarian reserve status has rarely been reported. We aimed to examine the overtime trend of thyroid hormones, thyroid peroxidase antibody (TPO Ab) and their associations with ovarian reserve status, identified by levels of age specific anti-mullerian hormone (AMH) in reproductive aged women, who participated in 12-year cohort of Tehran Thyroid Study (TTS).

METHODS

Reproductive age women(n = 775) without any thyroid disease or ovarian dysfunction were selected from the Tehran Thyroid Study cohort. Participants were divided into four age specific AMH quartiles (Q1-Q4), Q1, the lowest and Q4, the highest. AMH was measured at the initiation of study and thyroid stimulating hormone (TSH), free T4 (FT4), and TPO Ab were measured at baseline and at three follow up visits.

RESULTS

At baseline, there was no statistically significant difference in thyroid hormones between women of the four quartiles, although TPO Ab levels were higher in women of Q1. During the follow ups, FT4 was decreased in all quartiles (p < 0.05), whereas TPO Ab increased in Q1 (p = 0.02). Odds ratio of overall TPO Ab positivity in women of Q1 was 2.08 fold higher than those in Q4. (OR: 2.08, 95%CI: 1.16, 3.72; p = 0.01).

CONCLUSION

Women with the lowest ovarian reserves had higher levels of TPO Ab, with a positive trend of this antibody overtime in comparison to other quartiles, indicating that this group may be at a higher risk of hypothyroidism over time.

Assessment of adiposity distribution and its association with diabetes and insulin resistance: a population-based study

BACKGROUND

Rational measures in estimating adiposity distribution in diabetic patients has yet to be validated. This study aims to provide insight about the possible links between routinely available body adiposity parameters and the development of both diabetes and insulin resistance.

METHODS

We performed a population-based cross-sectional study in 9496 subjects aged 40 years or older. All of the body adiposity measures including body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), waist-height ratio (WHtR), visceral adiposity index (VAI), body adiposity index (BAI) and lipid accumulation product index (LAP) were separately evaluated according to standard measurement methods. Diabetes was diagnosed according to the American Diabetes Association 2010 criteria.

RESULTS

All tested body adiposity measurements were significantly associated with fasting plasma glucose (FPG), oral glucose tolerance test (OGTT) 2 h glucose, HbA1c and fasting insulin. Compared with other adiposity phenotypes, LAP have shown the relatively strongest while BAI have shown the relatively weakest association with increased odds of both diabetes and insulin resistance across all logistic regression models. Additionally, LAP provided the best discrimination accuracy for diabetes [area under the curve (AUC): 0.658 95% confidence intervals (CI) 0.645-0.671] and insulin resistance (AUC: 0.781 95% CI 0.771-0.792) when compared with other body adiposity parameters.

CONCLUSIONS

The LAP index seems to be a better indicator than other adiposity measures tested in the study to evaluate the association of visceral fat mass with diabetes and insulin resistance, which should be given more consideration in the clinical practice.

Optimal Cutoff Points for Anthropometric Variables to Predict Insulin Resistance in Polycystic Ovary Syndrome

BACKGROUND

Insulin resistance (IR) is a major cardiometabolic risk factor in females with polycystic ovary syndrome (PCOS). The euglycemic clamp is the gold standard method to measure IR. However, considering the time and cost that it takes, surrogate markers of IR are now widely used. The current study aimed at evaluating the cutoff points of even less invasive anthropometric and body composition variables to predict IR in females with PCOS.

METHODS

The current cross sectional study selected 224 females with PCOS, using Rotterdam criteria, referred to reproductive endocrinology research center; 88 of which were diagnosed with insulin resistance. Receiver operating characteristics curve was used to explore the best cutoff values of each anthropometric and body composition measures. IR was defined as homeostasis model assessment formula greater or equal to 2.6: HOMA-IR = fasting insulin (mU/L) × fasting plasma glucose (mM/L)/22.5.

RESULTS

The highest area under the curve (0.751) was for the multiplication of waist circumference (WC) by body mass index (BMI), as a single index. The highest sensitivity and specificity were for body water (BW) percentage (82% for values greater than 32.85%) and WC (79% for values greater than 88 cm), respectively.

CONCLUSIONS

It was concluded that there were simple anthropometric variables; e.g., WC × BMI, percentage of BW, and WC that could help to estimate IR in clinical settings especially when the gold standard or surrogate markers of IR were unavailable.

Effect of Metformin-sustained Release Therapy on Low-density Lipoprotein Size and Adiponectin in the South Indian Women with Polycystic Ovary Syndrome

OBJECTIVES

The aim of the study is to compare surrogate markers of cardiovascular disease (CVD) risk, such as adiponectin (APN) levels and low-density lipoprotein (LDL) size, before and after sustained release metformin (Met-SR) therapy in women with polycystic ovarian syndrome (PCOS).

METHODS

Sixty women with PCOS and sixty age-matched controls in the age group 18-45 years were recruited after obtaining informed consent. Women with PCOS were initiated on Met-SR 1 g orally, which was increased to 1.5 g after 2 weeks and continued up to 24 weeks. Demographic data along with family history of type 2 diabetes mellitus, PCOS, and CVD were collected. Lipid profile plasma APN levels and LDL size were measured before and after therapy in the PCOS group. Data analysis was performed using the GraphPad Prism-5 software.

RESULTS

Women with PCOS had greater dyslipidemia, lower APN level and LDL size, and increased lipid accumulating product index as compared to controls. After 6 months of Met-SR therapy, women with PCOS demonstrated significant increase in plasma APN levels and LDL size and significant decrease in weight, waist-hip ratio (WHR), waist circumference (WC), and blood pressure (BP). A significant decrease was observed in body mass index (BMI) in the overweight and obese PCOS subgroups.

CONCLUSION

Met-SR increases LDL size, APN concentration and decreases weight, WC, WHR, and BP in patients with PCOS. Met-SR may have salutary effects on LDL particle size through effects on APN levels in women with PCOS.

High insulin impaired ovarian function in early pregnant mice and the role of autophagy in this process

Metabolic disorders, such as PCOS (polycystic ovarian syndrome) and T2DM (type 2 diabetes mellitus), are associated with menstrual dysfunction, anovulation, infertility, and early pregnancy loss. Ovarian dysfunction is not only related to low pregnancy rates but also to the increased risk of miscarriage. Women with PCOS or T2DM, characterized by hyperinsulinemia, commonly experience ovarian dysfunction. In this study, we first explored whether high insulin levels directly affected ovarian functioning during embryo implantation. Mice in the insulin-treated group were given a subcutaneous injection of human recombinant insulin. After insulin treatment, serum levels of E2 (estrogen), PROG (progesterone), LH (luteinizing hormone), and FSH (follicle-stimulating hormone) were obviously lower, and there was a significant decrement of ovarian GDF9 (growth differentiation factor 9) mRNA. H&E (hematoxylin and eosin) staining showed a greater number of immature follicles and less luteinization in the insulin group. Further autophagy was studied in this process. A significant increase of P62 (SQSTM1/Sequestosome1) and a decrease of Cathepsin B, BECN1 (Beclin 1), and ULK1 (Unc-51-like kinase 1) mRNA in ovary was found in the insulin group. Western blot analysis showed that the expressions of LC3 (microtubule-associated protein 1 light chain 3), BECN1, and Cathepsin B proteins in ovaries from insulin group were obviously reduced, while P62 proteins were significantly increased. All these results illustrated that insulin could directly impair ovarian function during embryo implantation and the imbalance of ovarian autophagy due to insulin. Autophagy could enhance the impaired ovarian function results from insulin.

The predictive effect of inflammatory markers and lipid accumulation product index on clinical symptoms associated with polycystic ovary syndrome in nonobese adolescents and younger aged women

OBJECTIVE(S)

The aim of our study is to analyse the inflammatory markers and lipid accumulation product (LAP) index in nonobese adolescents and younger aged women with polycystic ovary syndrome (PCOS) compared with age and body mass index (BMI)-matched healthy controls and to determine whether the investigated parameters are potential markers for the etiopathogenesis of PCOS. We also aim to determine whether these inflammatory markers are predictive for developing some clinical implications, such as cardiovascular disease (CVD) and insulin resistance (IR), associated with PCOS.

STUDY DESIGN

A total of 34 adolescents and younger aged females with PCOS, and 33 age and BMI-matched healthy controls were recruited for our study. All participants were nonobese (BMI<25). Neopterin (NEO), C-reactive protein (CRP) levels and complete blood parameters were assessed. LAP index and homeostasis model assessment of IR (HOMA-IR) were calculated; anthropometric, clinical and biochemical parameters were also recorded.

RESULTS

Serum NEO, CRP levels and LAP index were significantly increased in nonobese adolescents and younger aged females with PCOS compared to healthy controls. We could not found any predictive effect of investigated inflammatory markers and LAP index on CVD risk among PCOS patients after adjustment for abdominal obesity. We also found a positive predictive effect of WBC and a negative predictive effect of lymphocytes on IR in PCOS patients after adjustment for abdominal obesity. We did not find any predictor effect of NEO on IR, but it was a positive predictive marker for an elevated HOMA-IR index.

CONCLUSION(S)

Elevated NEO, CRP levels and LAP index could have potential roles in the etiopathogenesis of PCOS in nonobese adolescents and younger aged females,NEO could be a predictive marker for elevated HOMA-IR index, and WBC and lymphocytes could be predictive for the development of IR among nonobese adolescents and younger aged females with PCOS.

Role of Versican and ADAMTS-1 in Polycystic Ovary Syndrome

OBJECTIVE

ADAMTS-1 is a matrix metalloproteinase which cleaves versican in the cumulus oocyte complex under the effect of luteinizing hormone surge in the periovulatory period. Altered levels may have a role in the pathogenesis of polycystic ovary syndrome (PCOS). We aimed to determine the serum versican and ADAMTS-1 (a disintegrin and metalloproteinase with thrombospondin motif-1) levels in PCOS patients and compare the results with healthy controls.

METHODS

Thirty-eight patients with PCOS and forty healthy controls aged between 15 and 22 years were included in the study. They were sampled according to their basal hormone, serum versican, and ADAMTS-1 levels. Serum versican and ADAMTS-1 levels were measured by enzyme-linked immunosorbent assay. A multivariate logistic regression model was used to identify the independent risk factors of PCOS.

RESULTS

Serum versican levels were significantly decreased in the PCOS group when compared with the controls. The best versican cut-off value for PCOS was calculated to be 33.65 with 76.74% sensitivity and 52.94% specificity. Serum versican levels, homeostasis model assessment of insulin resistance index, a Ferriman-Gallwey score higher than 8, and oligomenorrhea were the strongest predictors of PCOS. Serum versican levels were significantly decreased in PCOS patients. Besides, serum ADAMTS-1 and versican levels were significantly and positively correlated with each other.

CONCLUSION

Serum versican levels were significantly decreased in patients with PCOS. This suggests a possible role of versican in ovulatory dysfunction and in the pathogenesis of PCOS.

Lipid accumulation product as a marker of cardiometabolic susceptibility in women with different phenotypes of polycystic ovary syndrome

OBJECTIVE

There are limited data on cardiometabolic risk factors and the prevalence of metabolic syndrome (MetS) across the different PCOS phenotypes in Caucasian population. Lipid accumulation product (LAP) is a clinical surrogate marker that could be used for evaluation of MetS in clinical practice. The aim of the study was to analyze metabolic characteristics and the ability of LAP to predict MetS in different PCOS phenotypes.

DESIGN

Cross-sectional clinical study analyzing 365 women with PCOS divided into four phenotypes according to the ESHRE/ASRM criteria, and 125 healthy BMI-matched controls.

METHODS

In all subjects, LAP was determined and MetS was diagnosed according to the National Cholesterol Education Program/Adult Treatment Panel III (NCEP-ATP III), the International Diabetes Federation (IDF) and the Joint Interim Statement (JIS) criteria. Logistic regression and ROC curve analyses were used to determine predictors of MetS in each PCOS phenotype. All analyses were performed with age and BMI adjustment.

RESULTS

All PCOS phenotypes in comparison to controls had higher prevalence of MetS assessed by NCEP-ATP III criteria, and only classic phenotypes when IDF and JIS criteria were used. All phenotypes had the same prevalence of MetS irrespective of used definition. LAP and exhibited the highest diagnostic accuracy and was an independent predictor of MetS in all phenotypes.

CONCLUSION

LAP is an independent and accurate clinical determinant of MetS in all PCOS phenotypes in our Caucasian population. All PCOS phenotypes, including non-classic ones, are metabolically challenged and with cardiovascular risk, particularly phenotype B.

Lipid accumulation product and metabolic syndrome: a population-based study in northern Iran, Amol

PURPOSE

Lipid accumulation product (LAP) demonstrated a strong predictive accuracy for metabolic syndrome (MetS) in previous studies. This study was conducted to determine the predictive performance of LAP compared to obesity indexes. Moreover, the optimal cutoff point of LAP based on the study population waist circumference threshold was estimated in both men and women.

METHODS

5797 subjects with an average age of 44.77 ± 16.77 years for men and 43.78 ± 15.43 years for women were included in the present study. The ROC analysis was performed to assess the predictive accuracy of LAP in the diagnosis of MetS. The optimal cutoff point of LAP was determined according to maximal Youden index in both men and women.

RESULTS

The optimal cutoff points determined for LAP were 49.71 (sensitivity = 85.2 %, specificity = 82.3 %) for women and 39.89 (sensitivity = 86 %, specificity = 79.6 %) for men. Based on the assigned cutoff points, the prevalence of high LAP was obtained 44.1 % in men and 45.1 % in women. LAP also showed a significantly higher predictive performance for MetS compared to obesity measures and also TG.

CONCLUSION

LAP has a strong and reliable diagnostic accuracy for MetS in Iranian population in the north of Iran. LAP showed a better predictability than other obesity indexes assessed in the present study.

The association of thiol/disulphide homeostasis and lipid accumulation index with cardiovascular risk factors in overweight adolescents with polycystic ovary syndrome

OBJECTIVE

To assess thiol/disulphide homeostasis and lipid accumulation product index, and to determine whether they are associated with increased cardiovascular disease (CVD) risk or not in overweight adolescents with polycystic ovary syndrome (PCOS).

DESIGN

Case-control study.

SETTING

Education and Research Hospital.

PATIENTS

Group 1: 43 overweight+PCOS, Group 2: 45 normal weight+PCOS, Group 3: 27 overweight adolescents and Group 4: 96 age-matched, normal weight healthy controls.

INTERVENTIONS

Serum lipid profiles, hormonal parameters and thiol/disulphide homeostasis were measured. Lipid accumulation index (LAP index) and homeostasis model assessment (HOMA-IR) were calculated.

MAIN OUTCOME MEASURES

The relation between thiol/disulphide homeostasis and LAP index, and increased CVD risk were evaluated in overweight adolescents with PCOS.

RESULTS

Native and total thiol levels were significantly lower in overweight+PCOS adolescents when compared with both normal weight PCOS and control adolescents (P = 0·002). LAP index values were significantly higher in Group 1 when compared separately with the rest of the three groups (P < 0·001). Multivariable logistic regression analysis revealed serum total thiol levels of lower than 405·45 μmol/l were independently associated with increased risk of CVD in overweight PCOS adolescents (OR: 1·019, 95% CI: 1·001-1·036). In addition, a LAP index greater than 21·54 was also associated with increased CVD risk in overweight PCOS adolescents (OR: 1·270, 95% CI: 1·174-1·374).

CONCLUSION

In conclusion, we suggest that increased LAP index and decreased total thiol levels may contribute to the increased CVD risk in overweight adolescents with PCOS.

Insulin resistance in obesity and polycystic ovary syndrome: systematic review and meta-analysis of observational studies

We aimed at investigating whether insulin resistance (IR)/sensitivity are impaired in obese/non-obese polycystic ovary syndrome (PCOS) and obese/non-obese healthy controls. A comprehensive literature search was performed for observational, English language studies. Meta-analysis was performed with the random effects model according to the heterogeneity. Eligible studies, involving 3037 women in four groups of: 1-obese, PCOS; 2-non-obese, PCOS, 3-obese, non-PCOS and 4-Non-obese, non-PCOS were included. Based on the insulin resistance index (HOMA-IR) analysis, the pooled mean (95% Conf. Interval) of HOMA IR in groups 1-4 were 4.38 (3.84, 4.92), 2.68 (2.16, 3.20), 2.44 (2.06, 2.82) and 1.34 (1.06, 1.63), respectively. Meta-analysis showed that group 1 (obese, PCOS patients) statistically have the highest IR and group 4 (non-obese, non-PCOS women) have the highest insulin sensitivity. Group 2 (non-obese, PCOS patients) and group 3 (obese, non-PCOS women) were between this range and they had lower IR than group 1 (obese, PCOS) and lower insulin sensitivity than group 4 (non-obese, non-PCOS). So, there were statistical differences between all groups except between groups 2 and 3. Insulin sensitivity indexes (quickie and ISI), also confirm the IR index (HOMA-IR) results. Based on different IR/sensitivity indexes, we found no evidence of any different effects of BMI ≥ 30 kg/m(2) on IR/sensitivity. In conclusion, PCOS status intensifies the adverse effects of obesity on IR, it has to be appropriately addressed in primary and secondary preventive cares and treatments provided for these women.

Lipid accumulation product and incident cardiovascular events in a normal weight population: Tehran Lipid and Glucose Study

BACKGROUND

The lipid accumulation product (LAP) is a relatively new marker for measuring cardiovascular disease (CVD) risk factors. We investigated predictability of LAP value for incident CVD among Tehranian adults with normal BMI.

METHODS

A population based cohort of subjects without history of prevalent cardiovascular disease, aged ≥30 years who had BMI <25 were followed for a median (interquartile range 25-75) of 10.1 (7.25-10.57) years. Subjects were stratified according to LAP tertiles. LAP was defined as WC-58 × TG for women and WC-65 × TG for men (where WC is waist circumference and TG is triglycerides). Cox regression analyses were used to estimate the hazard ratio (HR) of CVD events; c-statistics test was also calculated to compare LAP with other anthropometric indices.

RESULT

In this prospective study of 2378 subjects (57.0% men) with mean age of 46.1 ± 13.5 years, and mean BMI 22.59 ± 1.9 kg/m(2) an increasing trend of cardiovascular risk factors along LAP tertiles (except for smoking and history of premature CVD events) was observed. During follow-up 160 CVD cases occurred (incidence rates (per 1000 person-years) of CVD across LAP tertiles were 4.14 (2.88-5.96), 6.82 (5.13-9.04) and 12.37 (9.97-15.34), respectively). Adjusted HRs for development of cardiovascular disease across LAP tertiles were 1.56 (95% confidence interval (CI) =0.91-2.69) and 2.17 (95% CI = 1.22-3.86) respectively. C-statistics of LAP were not significantly higher than other anthropometric measures for predicting incident CVD.

CONCLUSION

LAP is an independent predictor of cardiovascular events in normal BMI subjects, but is not superior over other anthropometrics indices.

Associations of blood lipid-related indices with blood pressure and pulse pressure in middle-aged men

INTRODUCTION

Low-density lipoprotein cholesterol to high-density lipoprotein cholesterol (LDL-C/HDL-C) ratio is known as a classical atherogenic index. In addition, triglycerides to HDL-C (TGs/HDL-C) ratio and lipid accumulation product (LAP) have been proposed to be good discriminators for cardiometabolic risk. The aim of this study was to determine which lipid index is most strongly associated with blood pressure and pulse pressure.

METHODS

The subjects were 36,536 Japanese men aged 35-60 years who were not receiving drug therapy for dyslipidemia. Relationships of each lipid index with blood pressure and pulse pressure were investigated by using linear and logistic regression analyses.

RESULTS

There were significant positive correlations of systolic and diastolic blood pressure and pulse pressure with the lipid-related indices such as LDL-C/HDL-C ratio, TGs/HDL-C ratio, and LAP. The correlations with LAP were significantly stronger than those with the LDL-C/HDL-C ratio and the TGs/HDL-C ratio. Odds ratios (ORs) for hypertension and high pulse pressure in subjects with versus subjects without high levels of each lipid-related index were significantly higher than the reference level of 1.00. The ORs of subjects with versus subjects without high LAP tended to be higher than the ORs of subjects with versus subjects without high LDL-C/HDL-C ratio or high TGs/HDL-C ratio. In the linear and logistic regression analyses, the associations of the lipid-related indices with pulse pressure were weaker than the corresponding associations with blood pressure.

CONCLUSION

LAP shows stronger associations with blood pressure and pulse pressure than the other lipid-related indices and is suggested to be better for discriminating the risk of hypertension.

Lipid accumulation product and 25-OH-vitamin D deficiency in type 2 diabetes

BACKGROUND

Emerging data suggest a link between vitamin D (25(OH)D) deficiency, type 2 diabetes (T2D), and visceral adiposity. The lipid accumulation product (LAP), strictly correlated with abdominal fat depots, is proposed as marker of dysfunctional adiposity.

AIM

To verify the association between 25(OH)D levels and LAP in T2D.

METHODS

Body mass index (BMI), waist circumference (WC), glucose, HbA1c, lipids, and 25(OH)D were assessed in 420 T2D outpatients and in 150 non-diabetic obese with similar anthropometric characteristics. LAP was computed as the product of sex-specific enlarged WC and triglycerides (TG).

RESULTS

In T2D patients, 63.0% showed 25(OH)D deficiency (<20 ng/ml) vs. 71.3% in the obese control group. Overweight males showed a higher prevalence of 25(OH)D deficiency (60.3%) than women (48.8%, p < 0.001), while in obese patients this prevalence was not significant. In both genders, 25(OH)D was not significantly associated with HbA1c and fasting glucose. Age-adjusted 25(OH)D levels were inversely correlated with BMI (p < 0.001), WC (p < 0.001), and LAP (p < 0.001) in both genders. Metabolic syndrome presented an odds ratio (OR) for 25(OH)D deficiency of 1.6 (1.1-2.5, p = 0.048) in females and 1.7 (1.2-2.7, p = 0.016) in males, while the highest quartile of LAP showed an OR of 2.1 (1.2-3.6, p = 0.019) in females and 3.2 (1.6-6.5, p = 0.02) in males. A similar trend was observed in the obese control group.

CONCLUSIONS

In the presence of excess weight, subjects with and without T2D frequently feature low 25(OH)D levels. Subjects with higher LAP exhibit a high risk of 25(OH)D deficiency, suggesting that dysfunctional adiposity is a worsening factor for vitamin D hypovitaminosis.