This study was undertaken to evaluate the association between components defining insulin resistance and breast cancer in women.
We conducted a systematic review of four databases (PubMed-Medline, ...EMBASE, Web of Science, and Scopus) for observational studies evaluating components defining insulin resistance in women with and without breast cancer. A meta-analysis of the association between insulin resistance components and breast cancer was performed using random effects models.
Twenty-two studies (n = 33,405) were selected. Fasting insulin levels were not different between women with and without breast cancer (standardized mean difference, SMD -0.03, 95%CI -0.32 to 0.27; p = 0.9). Similarly, non-fasting/fasting C-peptide levels were not different between the two groups (mean difference, MD 0.07, -0.21 to 0.34; p = 0.6). Using individual odds ratios (ORs) adjusted at least for age, there was no higher risk of breast cancer when upper quartiles were compared with the lowest quartile (Q1) of fasting insulin levels (OR Q2 vs. Q1 0.96, 0.71 to 1.28; OR Q3 vs. Q1 1.22, 0.91 to 1.64; OR Q4 vs. Q1 0.98, 0.70 to 1.38). Likewise, there were no differences for quartiles of non-fasting/fasting C-peptide levels (OR Q2 vs. Q1 1.12, 0.91 to 1.37; OR Q3 vs. Q1 1.20, 0.91 to 1.59; OR Q4 vs. Q1 1.40, 1.03 to 1.92). Homeostatic model assessment (HOMA-IR) levels in breast cancer patients were significantly higher than in people without breast cancer (MD 0.22, 0.13 to 0.31, p<0.00001).
Higher levels of fasting insulin or non-fasting/fasting C-peptide are not associated with breast cancer in women. HOMA-IR levels are slightly higher in women with breast cancer.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Objective To determine the association between thyroid hormones and insulin resistance in a population of healthy individuals. Materials and methods We conducted an analytical ...cross-sectional study in adults who attended a private clinic from 2012 to 2014. We excluded those participants with fasting glucose values compatible with diabetes mellitus, abnormal thyroid hormone values, chronic use of corticosteroids, and incomplete medical records. Participants were divided into tertiles (low, intermediate and high) according to their free triiodothyronine and free thyroxine values. We defined Insulin resistance as a Homeostasis Model Assessment (HOMA-IR) value greater than 3.8. We conducted a univariate and multivariate Poisson regression model to assess the association between thyroid hormones and insulin resistance. The association measure reported was the prevalence ratio (PR) with their confidence interval (CI) at 95%. Results We evaluated 600 participants. The mean age was 36.8 ± 14.2 years and 33% were male. The frequency of insulin resistance was 29.5%. In the univariate regression, we found association between free triiodothyronine tertiles and insulin resistance. In the multivariate regression adjusted for age, sex, body mass index and thyroid stimulating hormone, the association between free triiodothyronine tertiles and insulin resistance remained; intermediate tertile (PR = 1.54; CI95%: 1.10-2.15) and high tertile (PR = 1.70; CI95%: 1.21-2.39). We found no association between T4 and insulin resistance. Conclusions High levels of free triiodothyronine are associated with insulin resistance. The use of free trioodothyronine to assess insulin resistance in healthy patients should be considered.
To evaluate the association between high triglyceride/HDL-cholesterol (TG/HDL-C) ratio and insulin resistance (IR) or hyperinsulinemia after oral glucose tolerance test (OGTT) in normal-weight ...healthy adults.
We carried out an analytical cross-sectional study in euthyroid non-diabetic adults, who attended the outpatient service of a private clinic in Lima-Peru from 2012 to 2016. Participants were divided in two groups according to the presence or absence of high TG/HDL-C ratio, IR or hyperinsulinemia after OGTT. TG/HDL-C ratio values ≥ 3 were considered as high. IR was defined as a Homeostasis Model Assessment (HOMA-IR) value ≥ 2.28 and hyperinsulinemia after OGTT as a serum insulin value ≥ 80μU/mL after 120 min of 75-g glucose intake. We elaborated crude and adjusted Poisson generalized linear models to evaluate the association between high TG/HDL-C ratio and IR or hyperinsulinemia after OGTT and reported the prevalence ratio (PR) with their respective 95% confidence intervals (95%CI).
We analyzed the data of 118 individuals. Prevalence of high TG/HDL-C ratio was 17.8% (n = 21) while the prevalence of IR and hyperinsulinemia after OGTT was 24.6% (n = 29) and 17.0% (n = 20), respectively. TG/HDL-C-ratio values were positively correlated with HOMA-IR (r = 0.498; p < 0.01) and serum insulin after OGTT (r = 0.326; p < 0.001). In the adjusted model, high TG/HDL-C ratio was associated with both IR (aPR = 3.16; 95%CI: 1.80–5.77) and hyperinsulinemia after OGTT (aPR = 2.36; 95%CI: 1.20–4.63).
High TG/HDL-C ratio was associated with both IR markers used in our study, appearing to be a clinically useful tool to assess IR in euthyroid normal-weight adults without type 2 diabetes mellitus.
To assess the association between elevated triglycerides/glucose index (TGI) and insulin resistance (IR) or hyperinsulinemia after oral glucose tolerance test (OGTT) in a sample of healthy adults.
We ...conducted an analytical cross-sectional study in euthyroid non-diabetic adults, who attended the outpatient service of a private clinic in Lima-Peru during the 2012–2016 period. Participants were categorized in two groups according to the presence or absence of elevated TGI, IR or hyperinsulinemia after OGTT. A TGI value ≥ 8.65 was considered as elevated. We defined IR as a Homeostasis Model Assessment (HOMA-IR) value ≥ 2.28 and hyperinsulinemia after OGTT as a serum insulin value ≥ 80μU/mL after 120 min of 75-g glucose intake. We elaborated crude and adjusted Poisson regression models to assess the association between elevated TGI and IR or hyperinsulinemia after OGTT. The reported association measure was the prevalence ratio (PR) with their respective 95% confidence intervals (95%CI).
We analyzed 118 individuals, the average age was 37.5 ± 11.3 years, 21 (17.8%) were males and the median BMI was 22.7 ± 1.6 kg/m2. The prevalence of elevated TGI was 25.4% (n=30) while the prevalence of IR and hyperinsulinemia after OGTT was 24.6% (n=29) and 17.0% (n=20) respectively. In the adjusted model, elevated TGI was associated with both IR (aPR=6.36; 95%CI: 3.41–11.86) and hyperinsulinemia after OGTT (aPR=4.19; 95%CI: 1.81–9.70).
We found that elevated TGI was associated with both IR markers in a sample of euthyroid adults without T2DM and with a normal BMI. The simplicity of the TGI calculation makes it the first-choice alternative when the hyperinsulinemic-euglycemic clamp or HOMA-IR are not available.
To assess the association between high waist-to-hip ratio (WHR) levels and insulin resistance (IR) or hyperinsulinemia after oral glucose tolerance test (OGTT) in a sample of normal-weight women.
We ...conducted an analytical cross-sectional study in euthyroid non-diabetic women, who attended the outpatient service of a private clinic in Lima-Peru from 2012 to 2016. Participants were divided in two groups according to the presence or absence of high WHR levels, IR or hyperinsulinemia after OGTT. We considered WHR values > 0.85 as high levels. IR was defined as a Homeostasis Model Assessment (HOMA-IR) value > 2.39 and hyperinsulinemia after OGTT as a serum insulin value ≥ 80μU/mL after 120 min of 75-g glucose intake. We elaborated crude and adjusted Poisson generalized linear models to evaluate the association between high WHR levels and IR or hyperinsulinemia after OGTT and reported the prevalence ratio (PR) with their respective 95% confidence intervals (95%CI).
We analyzed the data of 248 euthyroid, non-diabetic and normal-weight women. The prevalence of high WHR levels was 68.9% (n = 171) while the prevalence of IR and hyperinsulinemia after OGTT was 25% (n = 62) and 15.3% (n = 38), respectively. WHR values were positively correlated with HOMA-IR (r = 0.307; p < 0.001) and serum insulin after OGTT (r = 0.260; p < 0.001). In the adjusted model, high WHR levels were associated with both IR (aPR = 2.63; 95%CI: 1.39–5.01) and hyperinsulinemia after OGTT (aPR = 2.35; 95%CI: 1.03–5.38).
High WHR levels were associated with both IR markers used in our study, appearing to be a useful anthropometric indicator to assess IR in euthyroid normal-weight women without type 2 diabetes mellitus.
To determine the association between serum levels of vitamin B12 and metabolic syndrome (MetS) in a population of euthyroid adults.
We carried out an analytical cross-sectional study in euthyroid ...adults of both sexes, who attended the outpatient service of a private clinic in Lima-Peru during the 2012–2016 period. Participants were divided into tertiles (low, intermediate and high) according to their serum vitamin B12 values. MetS was defined when three or more metabolic criteria were met by the participants. We elaborated crude and adjusted Poisson regression models to evaluate the association between the serum vitamin B12 tertiles and the presence of MetS. The reported association measure was the prevalence ratio (PR) with their respective 95% confidence intervals (95%CI).
We analyzed 346 participants, the average age was 38.3 ± 10.8 (SD) years, 117 (33.8%) were males, the serum vitamin B12 median was 364.1 (IQR: 274.2–473.4) pmol/L and the prevalence of MetS was 30.1% (n = 104). In the crude Poisson regression model, we found an association between the serum vitamin B12 tertiles and the presence of MetS, with marginal significance. The association gained statistical significance in the adjusted model by potential confounders; and compared with the low serum vitamin B12 tertile, the prevalence of MetS was 36% lower (aPR = 0.64; 95%CI: 0.43–0.96) among the high tertile group.
Euthyroid participants with elevated levels of serum vitamin B12 showed a lower prevalence of MetS compared to those who had low levels of this marker.
To determine the association between free triiodothyronine (FT3), free thyroxine (FT4) and free-triiodothyronine-to-free-thyroxine ratio (FT3/FT4) levels and Metabolic Syndrome (MetS).
We carried out ...an analytical cross-sectional study in euthyroid adults of both sexes, who attended the outpatient service of a private clinic in Lima-Peru during the 2014–2016 period. Participants were divided into tertiles (low, intermediate and high) according to their FT3, FT4, and FT3/FT4 ratio values. MetS was defined when three or more metabolic criteria were met by the participants. ROC curves were constructed, and Youden’s Index were used to identify the optimal cut-points of each thyroid marker. We elaborated crude/adjusted Poisson regression models to evaluate the association between the thyroid markers and the presence of MetS. The reported association measure was the prevalence ratio (PR) with their respective 95% confidence intervals (95% CI).
We analyzed 245 participants, the average age was 38.5 ± 10.3 years, 29.8% were males, and the prevalence of MetS was 31%. In the adjusted Poisson regression models, the prevalence of MetS was higher among the high FT3 tertile compared to the low tertile (aPR = 2.01; 95% CI: 1.22–3.34). The prevalence of MetS was higher among the intermediate FT3/FT4 ratio tertile and the high FT3/FT4 ratio tertile compared to the low tertile, (aPR = 1.78; 95% CI: 1.02–3.10) and (aPR = 2.80; 95% CI: 1.67–4.72); respectively. The highest areas under the curve (AUC) were found for FT3 and FT3/FT4 ratio with areas of 0.654 (95% CI: 0.58–0.73) and 0.649 (95% CI: 0.57–0.72); respectively.
Elevated levels of FT3 and FT3/FT4 ratio were associated with MetS in a euthyroid population.