C-Reactive Protein, Waist Circumference, and Family History of Heart Attack are Independent Predictors of Body Iron Stores in Apparently Healthy Premenopausal Women

Ferritin levels have been associated with metabolic syndrome and insulin resistance. The aim of the present study was to evaluate the prediction of ferritin levels by variables related to cardiometabolic disease risk in a multivariate analysis. For this aim, 123 healthy women (72 premenopausal and 51 posmenopausal) were recruited. Data were collected through procedures of anthropometric measurements, questionnaires for personal/familial antecedents, and dietary intake (24-h recall), and biochemical determinations (ferritin, C reactive protein (CRP), glucose, insulin, and lipid profile) in blood serum samples obtained. Multiple linear regression analysis was used and variables with no normal distribution were log-transformed for this analysis. In premenopausal women, a model to explain log-ferritin levels was found with log-CRP levels, heart attack familial history, and waist circumference as independent predictors. Ferritin behaves as other cardiovascular markers in terms of prediction of its levels by documented predictors of cardiometabolic disease and related disorders. This is the first report of a relationship between heart attack familial history and ferritin levels. Further research is required to evaluate the mechanism to explain the relationship of central body fat and heart attack familial history with body iron stores values.     

Serum 25-Hydroxyvitamin D and Insulin Resistance in Apparently Healthy Adolescents

Purpose

Vitamin D deficiency is a common condition that is associated with diabetes and insulin resistance. However, the association between vitamin D and insulin resistance has not been fully studied, especially in the general adolescent population. Therefore, we assessed the association between serum 25-hydroxyvitamin D [25(OH)D] level and insulin resistance among apparently healthy Korean adolescents.

Methods

A total of 260 (135 male and 125 female) adolescents in a rural high school were assessed for serum 25(OH)D, fasting plasma glucose, and insulin. All of the participants were aged 15 to 16 years old, and without known hypertension or diabetes. Serum 25(OH)D was analyzed both as a continuous and categorical variable in association with insulin resistance. Insulin resistance was estimated by homeostasis model assessment (HOMA-IR). Increased insulin resistance was operationally defined as a HOMA-IR value higher than the sex-specific 75th percentile.

Results

In male adolescents, every 10 ng/ml decrease in 25(OH)D level was associated with a 0.25 unit increase in HOMA-IR (p = 0.003) after adjusting for age and BMI. Compared to those in the highest quartile, male adolescents in the lowest 25(OH)D quartile were at significantly higher risk for insulin resistance: unadjusted odds ratio 4.06 (95% CI, 1.26 to 13.07); age and BMI adjusted odds ratio 3.59 (95% CI, 1.03 to 12.57). However, 25(OH)D level, either in continuous or categorical measure, was not significantly associated with insulin resistance among female adolescents.

Conclusions

This study suggests that serum 25(OH)D level may be inversely associated with insulin resistance in healthy male adolescents.     

Circulating Insulin Concentrations,Smoking, and Alcohol Intake Are Important Independent Predictors of Leptin in Young Healthy Men

Objective : Leptin, an adipocyte-secreted hormone, has been shown to signal the status of energy stores to the brain, regulate energy homeostasis, and mediate the neuroendocrine response to food deprivation. Obesity is associated with increased leptin levels, and several hormones, including insulin and glucocorticoids, have been associated with leptin levels and expression in rodents. Although obesity has been strongly associated with increased leptin in humans, a significant percentage of leptin's variability remains unexplained. The role of endogenous hormones, demographic factors, or certain life-style factors in explaining the residual variability of leptin levels has not yet been clarified. We performed this cross-sectional study to document the relative importance of obesity, lifestyle factor, and endogenous hormones in determining serum leptin levels. Research Methods and Procedures : We measured serum concentrations of insulin, Cortisol, testosterone, growth hormone, and dehydroepiandrosterone sulfate; ascertained anthropometric, demographic, and lifestyle characteristics; and studied these variables in relationship to serum leptin concentrations in a sample of young healthy men. Results : Obesity and alcohol intake were independently and positively associated with circulating leptin concentrations. Additionally, cigarette smoking was negatively and independently associated with leptin concentrations. Finally, serum insulin concentration was an independent hormonal determinant of circulating leptin concentrations, whereas serum testosterone was negatively associated with leptin only by bivariate analysis. Discussion : We conclude that, in addition to obesity, cigarette smoking, alcohol intake, and serum insulin levels are associated with leptin levels in a population of healthy young men.     

Cobalt Excretion Test for the Assessment of Body Iron Stores

Iron absorption is under delicate control and the level of absorption is adjusted to comply with the body''s need for iron. To measure the intestinal setting for iron absorption, and thereby indirectly assess body iron requirements, cobaltous chloride labelled with ⁵⁷Co or ⁶⁰Co was given by mouth and the percentage of the test dose excreted in the urine in 24 hours was measured in a gamma counter. Seventeen control subjects with normal iron stores excreted 18% (9-23%) of the dose. Increased excretion, 31% (23-42%), was found in 10 patients with iron deficiency anemia and in 15 patients with depleted iron stores in the absence of anemia. In contrast, 12 patients with anemia due to causes other than iron deficiency excreted amounts of radiocobalt within the normal control range. In patients with iron deficiency, replenishment of iron stores by either oral or parenteral iron caused the previously high results to return to normal.Excretion of the test dose was normal in portal cirrhosis with normal iron stores but it was markedly increased in patients with cirrhosis complicated by either iron deficiency or endogenous iron overload. It was also raised in primary hemochromatosis. Excretion of the dose was reduced in gluten-sensitive enteropathy. Gastrointestinal surgery and inflammatory disease of the lower small intestine had no effect on the results except that some patients with steatorrhea had diminished excretion.The cobalt excretion test provides the clinician with a tool for the assessment of iron absorption, the detection of a reduction in body iron stores below the level that is normal for the subject in question, the differentiation of iron deficiency anemia from anemia due to other causes, and the investigation of patients with iron-loading disorders.     

Endocrine Determinants of Changes in Insulin Sensitivity and Insulin Secretion during a Weight Cycle in Healthy Men

ObjectiveChanges in insulin sensitivity (IS) and insulin secretion occur with perturbations in energy balance and glycemic load (GL) of the diet that may precede the development of insulin resistance and hyperinsulinemia. Determinants of changes in IS and insulin secretion with weight cycling in non-obese healthy subjects remain unclear.MethodsIn a 6wk controlled 2-stage randomized dietary intervention 32 healthy men (26±4y, BMI: 24±2kg/m²) followed 1wk of overfeeding (OF), 3wks of caloric restriction (CR) containing either 50% or 65% carbohydrate (CHO) and 2wks of refeeding (RF) with the same amount of CHO but either low or high glycaemic index at ±50% energy requirement. Measures of IS (basal: HOMA-index, postprandial: Matsuda-ISI), insulin secretion (early: Stumvoll-index, total: tAUC-insulin/tAUC-glucose) and potential endocrine determinants (ghrelin, leptin, adiponectin, thyroid hormone levels, 24h-urinary catecholamine excretion) were assessed.ResultsIS improved and insulin secretion decreased due to CR and normalized upon RF. Weight loss-induced improvements in basal and postprandial IS were associated with decreases in leptin and increases in ghrelin levels, respectively (r = 0.36 and r = 0.62, p<0.05). Weight regain-induced decrease in postprandial IS correlated with increases in adiponectin, fT3, TSH, GL of the diet and a decrease in ghrelin levels (r-values between -0.40 and 0.83, p<0.05) whereas increases in early and total insulin secretion were associated with a decrease in leptin/adiponectin-ratio (r = -0.52 and r = -0.46, p<0.05) and a decrease in fT4 (r = -0.38, p<0.05 for total insulin secretion only). After controlling for GL associations between RF-induced decrease in postprandial IS and increases in fT3 and TSH levels were no longer significant.ConclusionWeight cycling induced changes in IS and insulin secretion were associated with changes in all measured hormones, except for catecholamine excretion. While leptin, adiponectin and ghrelin seem to be the major endocrine determinants of IS, leptin/adiponectin-ratio and fT4 levels may impact changes in insulin secretion with weight cycling.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01737034","term_id":"NCT01737034"}}NCT01737034     

Both Hepatic and Body Iron Stores Are Increased in Dysmetabolic Iron Overload Syndrome. A Case-Control Study

Background & Aims

Hepatic iron is increased in dysmetabolic iron overload syndrome (DIOS). Whether this reflects elevated body iron stores is still debated. The study was aimed at assessing body iron stores in DIOS patients by calculating the amount of mobilized iron (AMI).

Methods

We conducted a prospective case-control study comparing AMI in 12 DIOS patients and 12 overweight normoferritinemic subjects matched on BMI and age. All participants were phlebotomized until serum ferritin dropped ≤ 50μg/L.

Results

The two groups were comparable with respect to metabolic abnormalities and differed according to serum ferritin levels only. AMI was significantly (p<0.0001) higher in DIOS (2.5g±0.7) than in controls (0.8g±0.3). No side effects were related to phlebotomies.     

Cross-Talk Between Body Iron Stores and Diabetes: Iron Stores are Associated with Activity and Microsatellite Polymorphism of the Heme Oxygenase and Type 2 Diabetes

To assess the relationship between the length of (GT) _n repeats in HO-1 gene promoter and heme oxygenase (HO) enzymatic activity in mononuclear cells with iron (Fe) stores in type 2 diabetic mellitus (DM2) patients and metabolic syndrome (MS) subjects, we studied 163 patients with DM2, 185 with MS, and 120 controls subjects. We evaluated iron status (hemoglobin and serum Fe, ferritin, and transferrin receptor), and we determined the length of (GT) _n repeats in HO-1 gene promoter by capillary electrophoresis and HO enzymatic activity in mononuclear cells and assessed the relationship between these results and Fe stores. Only 1/163, 6/185, and 7/120 had iron deficiency anemia in DM2 patients, MS subjects, and controls, respectively. No iron overload (ferritin >200 μg/L) was detected in all the subjects studied. DM2 patients had higher iron deposits, total body iron, and heme oxygenase activity (a suggestion of high oxidative stress condition) than MS subjects and controls. In DM2, we found a positive association between serum iron and HO activity. There were no difference in allelic frequency between the three groups; however, among DM2 and MS patients, the frequency of short/medium (SM) genotype of (GT) _n repetition was increased and medium/medium (MM) genotype of (GT) _n repetition was lower than controls. These results imply that DM2 patients and individuals with MS carrying SM repeats might have higher susceptibility to develop diabetes consequences. This increased susceptibility could be Fe-mediated oxidative stress.     

Relation of Misperception of Healthy Weight to Obesity in Urban Black Men

This study examined the relation between misperception of healthy weight and obesity, as well as moderators of this relation, in a sample of middle‐aged black men. Survey data from 404 mostly immigrant, black males living in greater New York City were collected as part of a larger randomized controlled trial. Data included measures of health status, BMI, perceived healthy weight, and misperception of healthy weight. Misperception of healthy weight was more frequent among obese men (90.2%) than nonobese men (48.7%) (P < 0.001). Mean level of misperception was also significantly higher in obese men than nonobese men (P < 0.001). Health status moderated the relation between misperception of healthy weight and obesity: obese men who felt healthy or who had fewer comorbid conditions had greater misperception of healthy weight than obese men who felt unhealthy or had relatively more comorbid conditions (P < 0.01). Our findings demonstrate that misperception of healthy weight discriminates between obese and nonobese black men, and the magnitude of this relation is exacerbated in obese men who are relatively healthy. Future studies should determine the prevalence of misperception of healthy weight in more diverse populations and identify potential mediators of the relation between misperception of healthy weight and obesity.     

Insulin Resistance Is an Independent Determinate of ED in Young Adult Men

Background

Insulin resistance (IR) triggers endothelial dysfunction, which contributes to erectile dysfunction (ED) and cardiovascular disease.

Aim

To evaluate whether IR was related to ED in young adult patients.

Methods

A total of 283 consecutive men complaining of ED at least six months were enrolled, with a full medical history, physical examination, and laboratory tests collected. Quantitative Insulin Sensitivity Check Index (QUICKI) was used to determine IR. The severity of ED was assessed by IIEF-5 questionnaire. Endothelial function was assessed by ultrasonographic examination of brachial artery flow mediated dilation (FMD).

Results

IR was detected in 52% patients. Subjects with IR had significant higher total cholesterol, triglycerides, low density lipoprotein-cholesterol (LDL-c), glycated haemoglobin (HBA1c), high sensitivity C-reactive protein (hs-CRP) and body mass index (BMI), but showed significant lower IIEF-5 score, FMD%, high density lipoprotein -cholesterol (HDL-c), testosterone, sex hormone binding globulin (SHBG) levels than patients without IR. Multiple regression analysis showed QUICKI and testosterone were independent predictors of IIEF-5 score. Furthermore, the incidence of IR was correlated with the severity of ED.

Conclusions

Compared with other CVFs, IR was found as the most prevalent in our subjects. Besides, IR was independently associated with ED and its severity, suggesting an adverse effect of insulin resistance on erectile function.     

Metabolic Adaptations to Dexamethasone‐Induced Insulin Resistance in Healthy Volunteers

Objective : Insulin resistance is observed in individuals with normal glucose tolerance. This indicates that increased insulin secretion can compensate for insulin resistance and that additional defects are involved in impaired glucose tolerance or type 2 diabetes. The objective of this study was to evaluate a procedure aimed at assessing the compensatory mechanisms to insulin resistance. Research Methods and Procedures : Eight healthy nonobese female patients were studied on two occasions, before and after administration of 2 mg/d dexamethasone for 2 days during a two‐step hyperglycemic clamp. Insulin secretion was assessed from plasma insulin concentrations. Insulin sensitivity was assessed from the ratio of whole‐body glucose use (6, 6 ²H₂ glucose) to plasma insulin concentrations. This procedure is known to induce a reversible impairment of glucose tolerance and insulin resistance. Results : In all subjects, dexamethasone induced a decrease in insulin sensitivity and a proportionate increase in first‐phase insulin secretion and in insulin concentrations at both steps of glycemia. The resulting hyperinsulinemia allowed the restoration of normal whole‐body glucose uptake and the suppression of plasma free fatty acids and triglycerides. In contrast, the suppression of endogenous glucose production was impaired after dexamethasone (p < 0.01). Discussion : Increased insulin secretion fully compensates dexamethasone‐induced insulin resistance in skeletal muscle and adipose tissue but not in the liver. This suggests that failure to overcome hepatic insulin resistance can impair glucose tolerance. The compensatory insulin secretion in response to insulin resistance can be assessed by means of a hyperglycemic clamp after a dexamethasone challenge.     

Relationships between Insulin Sensitivity and Measures of Body Fat in Asymptomatic Men and Women

Objective: To assess whether measures of body fat by DXA scanning can improve prediction of insulin sensitivity (S_I) beyond what is possible with traditional measures, such as BMI, waist circumference, and waist‐to‐hip ratio (WHR). Research Methods and Procedures: Frequently sampled intravenous glucose tolerance tests were performed in 256 asymptomatic non‐Hispanic white subjects from Rochester, MN (age 19‐60 years; 123 men and 133 women) to determine the S_I index by Bergman's minimal model technique. Height, weight, and waist and hip circumferences were measured for calculation of BMI and WHR; DXA was used to determine fat in the head, upper body, abdomen, and lower body. Linear regression was used to assess their relationships with S_I after sex stratification and adjustment for age. Results: After controlling for age, increases in traditional and DXA measures of fat were consistently associated with smaller declines in S_I among women than among men. In men, after controlling for age, all of the predictive information of S_I was provided by waist circumference (additional R² = 0.39, p < 0.001); none of the DXA measures improved the ability to predict S_I. In women, after adjustment for age, BMI, and WHR, the only DXA measure that improved the prediction of S_I was percentage head fat (additional R² = 0.03, p < 0.001). Discussion: Equivalent increases in most measures of body fat had lesser impact on S_I in women than in men. In both sexes, the predictive information provided by DXA measures is approximately equal to, but not additive to, that provided by simpler, traditional measures.     

Circadian Neuroendocrine Role in Age-Related Changes in Body Fat Stores and Insulin Sensitivity of the Male Sprague-Dawley Rat

A role for circadian neuroendocrine rhythms in the age-related development of obesity and insulin resistance was investigated in the male Sprague-Dawley rat. The phases and amplitudes of the plasma rhythms of several metabolic hormones (i.e. corticosterone, prolactin, insulin, and triiodothyronine) differed in lean, insulin-sensitive (3-week-old rats). insulin-resistant (8-week-old rats) and obese, insulin-resistant (44-week-old rats) animals. Simulation of the daily rhythms of endogenous corticosterone and prolactin by daily injections of the hormones at times corresponding to the peak levels found in 3-week-old rats reversed age-related increases in insulin resistance and body fat in older (5-6-month-old) rats. Ten such daily injections of corticosterone and prolactin in 12-14-week-old rats produced long-term reductions in body fat stores (30%). plasma insulin concentration (40%″). and insulin resistance (60%) (determined by a glucose tolerance test) measured 11-14 weeks after the treatment. Alterations in circadian neuroendocrine rhythms may account for age-related changes in carbohydrate and lipid metabolism in the male Sprague-Dawley rat, and resetting of these rhythms by appropriately timed daily injections of corticosterone and prolactin may help maintain metabolism characteristic of younger animals.     

Circadian Neuroendocrine Role in Age-Related Changes in Body Fat Stores and Insulin Sensitivity of the Male Sprague-Dawley Rat

A role for circadian neuroendocrine rhythms in the age-related development of obesity and insulin resistance was investigated in the male Sprague-Dawley rat. The phases and amplitudes of the plasma rhythms of several metabolic hormones (i.e. corticosterone, prolactin, insulin, and triiodothyronine) differed in lean, insulin-sensitive (3-week-old rats). insulin-resistant (8-week-old rats) and obese, insulin-resistant (44-week-old rats) animals. Simulation of the daily rhythms of endogenous corticosterone and prolactin by daily injections of the hormones at times corresponding to the peak levels found in 3-week-old rats reversed age-related increases in insulin resistance and body fat in older (5-6-month-old) rats. Ten such daily injections of corticosterone and prolactin in 12-14-week-old rats produced long-term reductions in body fat stores (30%). plasma insulin concentration (40%'). and insulin resistance (60%) (determined by a glucose tolerance test) measured 11-14 weeks after the treatment. Alterations in circadian neuroendocrine rhythms may account for age-related changes in carbohydrate and lipid metabolism in the male Sprague-Dawley rat, and resetting of these rhythms by appropriately timed daily injections of corticosterone and prolactin may help maintain metabolism characteristic of younger animals.     

Relationship between Insulin Resistance and Coronary Artery Calcium in Young Men and Women

Background

The gender disparity in cardiovascular disease (CVD) risk is greatest between young men and women. However, the causes of that are not fully understood. The objective of this study was to evaluate the relationship between insulin resistance and the presence of coronary artery calcium (CAC) to identify risk factors that may predispose young men and women to CVD.

Methodology/Principal Findings

Insulin resistance and CVD risk factors were examined in 8682 Korean men and 1829 women aged 30–45 years old. Insulin resistance was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR), and CAC was measured using computed tomography. Women were less likely to be insulin resistant (upper quartile of HOMA-IR, 18% vs. 27%, p<0.001) and had a lower prevalence of CAC (1.6% vs. 6.4%, p<0.001). Even when equally insulin resistant men and women were compared, women continued to have lower prevalence of CAC (3.1% vs. 7.2%, p = 0.004) and a more favorable CVD risk profile. Finally, after adjustment for traditional CVD risk factors, insulin resistance remained an independent predictor of CAC only in men (p = 0.03).

Conclusions/Significance

Young women have a lower risk for CVD and a lower CAC prevalence compared with men. This favorable CVD risk profile in women appears to occur regardless of insulin sensitivity. Unlike men, insulin resistance was not a predictor of CAC in women in this cohort. Therefore, insulin resistance has less impact on CVD risk and CAC in young women compared with men, and insulin resistance alone does not explain the gender disparity in CVD risk that is observed at an early age.     

Visceral Fat Accumulation,Insulin Resistance,and Elevated Depressive Symptoms in Middle-Aged Japanese Men

Objective

To investigate visceral fat accumulation and markers of insulin resistance in relation to elevated depressive symptoms (EDS).

Methods

Participants were 4,333 male employees (mean age, 49.3 years) who underwent abdominal computed tomography scanning, measured fasting insulin, and did not self-report diabetes and mental disorders under treatment and history of cancer, myocardial infarction, and stroke. Multivariable logistic regression was used to assess the association of EDS with abdominal fat deposition and markers of insulin resistance.

Results

Visceral fat area (VFA) and fasting insulin were significantly, positively associated with EDS. Multivariable-adjusted odds ratios (95% confidence interval) of high VFA for the lowest through highest quartile of depression score were 1 (reference), 1.18 (0.97–1.42), 1.25 (1.02–1.54), 1.23 (1.01–1.51), respectively, and corresponding figures for high fasting insulin were 1 (reference), 0.98 (0.80–1.19), 1.12 (0.91–1.38), and 1.29 (1.06–1.57), respectively. Subcutaneous fat area was not associated with EDS.

Conclusions

Results suggest that EDS is related to visceral, but not subcutaneous, fat accumulation and insulin resistance in middle-aged Japanese men.     

Brown Adipose Tissue,Whole‐Body Energy Expenditure,and Thermogenesis in Healthy Adult Men

Brown adipose tissue (BAT) can be identified by ¹⁸F‐fluorodeoxyglucose (FDG)‐positron emission tomography (PET) in adult humans. Thirteen healthy male volunteers aged 20–28 years underwent FDG‐PET after 2‐h cold exposure at 19 °C with light‐clothing and intermittently putting their legs on an ice block. When exposed to cold, 6 out of the 13 subjects showed marked FDG uptake into adipose tissue of the supraclavicular and paraspinal regions (BAT‐positive group), whereas the remaining seven showed no detectable uptake (BAT‐negative group). The BMI and body fat content were similar in the two groups. Under warm conditions at 27 °C, the energy expenditure of the BAT‐positive group estimated by indirect calorimetry was 1,446 ± 97 kcal/day, being comparable with that of the BAT‐negative group (1,434 ± 246 kcal/day). After cold exposure, the energy expenditure increased markedly by 410 ± 293 (P < 0.05) and slightly by 42 ± 114 kcal/day (P = 0.37) in the BAT‐positive and ‐negative groups, respectively. A positive correlation (P < 0.05) was found between the cold‐induced rise in energy expenditure and the BAT activity quantified from FDG uptake. After cold exposure, the skin temperature in the supraclavicular region close to BAT deposits dropped by 0.14 °C in the BAT‐positive group, whereas it dropped more markedly (P < 0.01) by 0.60 °C in the BAT‐negative group. The skin temperature drop in other regions apart from BAT deposits was similar in the two groups. These results suggest that BAT is involved in cold‐induced increases in whole‐body energy expenditure, and, thereby, the control of body temperature and adiposity in adult humans.     

Changes of Iron Stores and Duodenal Transepithelial Iron Transfer During Regular Exercise in Rats

It is unclear whether regular exercise depletes body iron stores and how exercise regulates iron absorption. In this study, growing female Sprague–Dawley rats were fed a high-iron diet (300 mg iron/kg) and subjected to swimming for 1, 3, or 12 months. Their body weight, liver nonheme iron content (NHI), spleen NHI, blood hemoglobin (Hb) concentration, hematocrit (Hct), and kinetics of ⁵⁹Fe transfer across isolated duodenal segments were then compared with sedentary controls. The main results were as follows: exercise for 1 month enhanced the transepithelial ⁵⁹Fe transfer and increased liver NHI content and Hb concentration; exercise for 3 months inhibited transepithelial ⁵⁹Fe transfer without affecting the liver and spleen NHI content, Hb concentration, and Hct; exercise for 12 months did not affect these parameters as compared with the corresponding sedentary controls; and the changes in transepithelial iron transfer were not associated with basolateral iron transfer. Our findings demonstrated that chronic, regular exercise in growing rats with a high dietary iron content does not deplete iron stores in the liver and spleen and may possibly enhance or inhibit duodenal iron absorption and even maintain duodenal iron absorption at the sedentary level, at least, in part depending on growth.     

Work and Family Characteristics as Predictors of Early Retirement in Married Men and Women

This study presents an integrative model of early retirement using data from the Wisconsin Longitudinal Study. The model extends prior work by incorporating work-family conflict to capture the interaction between the work and family domains and by assuming proximal and distal predictors of early retirement. More precisely, the model suggests that family and job demands and resources predict family-to-work and work-to-family conflict, respectively. All of these factors are presumed to have only indirect effects on retirement timing via the intervening effect of quality of life measures, that is, marital satisfaction, job satisfaction and health. The authors assume that these three factors constitute predictors of early retirement in addition to socioeconomic status and the availability of a pension plan and health insurance. The model was tested with structural equation modeling techniques, and the results were supportive. Therefore, the proposed model offers a general framework for the integration of previous research findings.