The association between serum albumin levels and metabolic syndrome in a rural population of Korea

C-reactive protein to albumin ratio and risk of incident metabolic syndrome in community-dwelling adults: longitudinal findings over a 12-year follow-up period

AIM

The C-reactive protein to albumin (CRP/Alb) ratio has emerged as a novel biomarker for various inflammatory diseases. This study aimed to evaluate the association between the CRP/Alb ratio and incident metabolic syndrome (MetS) with a large-sample, community-based Korean cohort over a 12-year follow-up period.

MATERIALS AND METHODS

Among 10,030 participants, a total of 6205 participants aged 40-69 years without MetS were selected from the Korean Genome and Epidemiology Study (KoGES). The baseline CRP/Alb ratio was divided into quartiles. The definition of newly developed MetS was the one proposed by the 2009 Joint Interim Statement of Circulation. Hazard ratios (HRs) with 95% confidence intervals (CIs) for incident MetS were calculated using multivariable Cox proportional hazards regression models after adjusting for potentially confounding variables.

RESULTS

During the 12-year follow-up period, MetS developed in 2535 subjects (40.9%, 2535/6205) with an incidence rate of 5.6-11.9 (over 2 years). Compared to the reference first quartiles, the HRs (95% CIs) of incident MetS in the second, third, and fourth quartiles increased in a dose-response manner. Compared to the reference quartile, the HRs (95% CIs) of the incidence of MetS for the second, third, and fourth quartiles of CRP/Alb ratio were 1.12 (0.99-1.27), 1.24 (1.11-1.40), and 1.51 (1.34-1.69) after adjusting for age, sex, smoking status, alcohol intake, physical activity, total cholesterol, mean arterial pressure, HOMA-IR, and total energy intake.

CONCLUSIONS

High CRP/Alb ratio at baseline may be a useful surrogate indicator of future incident MetS.

Joint modeling of association networks and longitudinal biomarkers: An application to childhood obesity

The prevalence of chronic non-communicable diseases such as obesity has noticeably increased in the last decade. The study of these diseases in early life is of paramount importance in determining their course in adult life and in supporting clinical interventions. Recently, attention has been drawn to approaches that study the alteration of metabolic pathways in obese children. In this work, we propose a novel joint modeling approach for the analysis of growth biomarkers and metabolite associations, to unveil metabolic pathways related to childhood obesity. Within a Bayesian framework, we flexibly model the temporal evolution of growth trajectories and metabolic associations through the specification of a joint nonparametric random effect distribution, with the main goal of clustering subjects, thus identifying risk sub-groups. Growth profiles as well as patterns of metabolic associations determine the clustering structure. Inclusion of risk factors is straightforward through the specification of a regression term. We demonstrate the proposed approach on data from the Growing Up in Singapore Towards healthy Outcomes cohort study, based in Singapore. Posterior inference is obtained via a tailored MCMC algorithm, involving a nonparametric prior with mixed support. Our analysis has identified potential key pathways in obese children that allow for the exploration of possible molecular mechanisms associated with childhood obesity.

Prevalence of Non-alcoholic Fatty Liver Disease Detected by Computed Tomography in the General Population Compared with Ultrasonography

Objective To assess the prevalence and clinical correlates of non-alcoholic fatty liver disease (NAFLD) identified by computed tomography (CT) in the general population compared with ultrasonography (US). Methods Four hundred and fifty-eight subjects who received health checkups at Meijo Hospital in 2021 and underwent CT within a year of US in the past decade were analyzed. The mean age was 52.3±10.1 years old, and 304 were men. Results NAFLD was diagnosed in 20.3% by CT and in 40.4% by the US. The NAFLD prevalence in men was considerably greater in subjects 40-59 years old than in those ≤39 years old and in those ≥60 years old by both CT and US. The NAFLD prevalence in women was substantially higher in the subjects 50-59 years old than in those ≤49 years old or those ≥60 years old on US, while no significant differences were observed on CT. The abdominal circumference, hemoglobin value, high-density lipoprotein cholesterol level, albumin level, and diabetes mellitus were independent predictors of NAFLD diagnosed by CT. The body mass index, abdominal circumference, and triglyceride level were independent predictors of NAFLD diagnosed by the US. Conclusion NAFLD was found in 20.3% of CT cases and 40.4% of US cases among recipients of health checkups. An "inverted U curve" in which the NAFLD prevalence rose with age and dropped in late adulthood was reported. NAFLD was associated with obesity, the lipid profile, diabetes mellitus, hemoglobin values, and albumin levels. Our research is the first in the world to compare the NAFLD prevalence in the general population simultaneously by CT and US.

Serum Albumin as Prognostic Marker for Older Adults in Hospital and Community Settings

Serum albumin, known for its multifaceted role in health, is hypothesized to serve as a prognostic marker for older adults, both in hospital and community settings. Nine studies were included in the review, revealing consistent associations between low serum albumin levels and increased mortality risk in hospitalized older individuals. In community settings, low serum albumin levels were linked to higher mortality rates compared to those with normal levels. The synthesis of evidence underscores the potential of serum albumin as a prognostic marker for older adults, offering valuable insights for risk stratification and targeted interventions. While robust evidence supports its utility in hospital settings, further research is warranted in community settings to address current limitations and enhance the applicability of serum albumin as a prognostic tool. This review merges existing knowledge of the prognostic significance of serum albumin in older adults across hospital and community settings. The findings emphasize the importance of serum albumin as a potential prognostic marker, urging continued research efforts to refine its application in diverse healthcare contexts and improve outcomes for the aging population.

Assessment of Subnutritional Indices and Associated Risk Factors of Malnutrition Among Older Adults

Malnutrition is a multifactorial problem affecting older adults especially in developing countries like Nigeria. Eighty-five subjects which comprise 55 older adults and 30 controls were recruited. Total protein, Albumin, Calcium, Vitamin-C and Vitamin D were estimated using Biuret's method, Bromo-Cresol Green method, O-Cresolphthalein-Complexone, High performance liquid chromatography, and ELISA methods respectively. Cognitive and nutritional status information were obtained using Mini-Cog test and MNA-short form. Data were analyzed at p < .05. Activities of daily living (ADL) was observed to be associated with nutritional status in older adults. The prevalence of older adults at risk of malnutrition was found to be 58.2%. Blood pressure, albumin and total protein were significantly higher in older adults (p < .05) compared to the younger adults. Total protein was significantly higher in older female subjects (p < .05) compared to older male subjects. It was also significantly higher in non- institutionalized older adults than in those who were institutionalized. Calf circumference was significantly lower (p < .05) in those with poor cognitive status. BMI and calcium were significantly lower in the malnourished older adults. It is concluded that older adults who are dependent, most of which are institutionalized may be more exposed to malnutrition, frailty and cognitive impairment.

Serum albumin, cardiometabolic and other adverse outcomes: systematic review and meta-analyses of 48 published observational cohort studies involving 1,492,237 participants

Objectives. A general body of evidence suggests that low serum albumin might be associated with increased risk of adverse cardiometabolic outcomes, but findings are divergent. We aimed to quantify associations of serum albumin with the risk of type 2 diabetes (T2D), cardiovascular disease (CVD), all-cause mortality, and other adverse outcomes using a systematic review and meta-analyses of published observational cohort studies. Design. MEDLINE, Embase, Web of Science, and manual search of relevant bibliographies were systematically searched to January 2020. Relative risks (RRs) with 95% confidence intervals (CIs) comparing top versus bottom thirds of serum albumin levels were pooled. Results. Fifty-four articles based on 48 unique observational cohort studies comprising of 1,492,237 participants were eligible. Multivariable adjusted RRs (95% CIs) comparing the top vs bottom third of serum albumin levels were: 1.03 (0.86-1.22) for T2D; 0.60 (0.53-0.67) for CVD; 0.74 (0.66-0.84) for coronary heart disease (CHD); 0.57 (0.36-0.91) for CHD death; 0.76 (0.65-0.87) for myocardial infarction; 0.66 (0.55-0.77) for all-cause mortality; 0.71 (0.61-0.83) for venous thromboembolism; 0.65 (0.48-0.88) for cancer mortality; and 0.62 (0.46-0.84) for fracture. Heterogeneity between contributing studies of T2D was partly explained by sample sizes of studies (p for meta-regression = .035). Conclusions. Elevated levels of serum albumin are associated with reduced risk of vascular outcomes, all-cause mortality, certain cancers, and fracture. Inconsistent findings for T2D may be attributed to selective reporting by studies. Further research is needed to assess any potential causal relevance to these findings and the role of serum albumin concentrations in disease prevention.Systematic review registration: PROSPERO 2019: CRD42019125869.

Insulin resistance and chronic kidney disease progression, cardiovascular events, and death: findings from the chronic renal insufficiency cohort study

BACKGROUND

Insulin resistance contributes to the metabolic syndrome, which is associated with the development of kidney disease. However, it is unclear if insulin resistance independently contributes to an increased risk of chronic kidney disease (CKD) progression or CKD complications. Additionally, predisposing factors responsible for insulin resistance in the absence of diabetes in CKD are not well described. This study aimed to describe factors associated with insulin resistance and characterize the relationship of insulin resistance to CKD progression, cardiovascular events and death among a cohort of non-diabetics with CKD.

METHODS

Data was utilized from Chronic Renal Insufficiency Cohort Study participants without diabetes (N = 1883). Linear regression was used to assess associations with insulin resistance, defined using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). The relationship of HOMA-IR, fasting glucose, hemoglobin A1c (HbA1c), and C-peptide with CKD progression, cardiovascular events, and all-cause mortality was examined with Cox proportional hazards models.

RESULTS

Novel positive associations with HOMA-IR included serum albumin, uric acid, and hemoglobin A1c. After adjustment, HOMA-IR was not associated with CKD progression, cardiovascular events, or all-cause mortality. There was a notable positive association of one standard deviation increase in HbA1c with the cardiovascular endpoint (HR 1.16, 95% CI: 1.00-1.34).

CONCLUSION

We describe potential determinants of HOMA-IR among a cohort of non-diabetics with mild-moderate CKD. HOMA-IR was not associated with renal or cardiovascular events, or all-cause mortality, which adds to the growing literature describing an inconsistent relationship of insulin resistance with CKD-related outcomes.

U-shaped association between serum albumin and development of chronic kidney disease in general hypertensive patients

BACKGROUND & AIMS

We aimed to examine the association between serum albumin (SAlb) and the development of chronic kidney disease (CKD), and examine any possible effect modifiers in general hypertensive patients with normal renal function and with no previous cardiovascular diseases (CVD).

METHODS

This is a post-hoc analysis (performed at May, 2018) of 12,621 hypertensive adults with estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m² and SAlb ≥35.0 g/L from the renal sub-study of the China Stroke Primary Prevention Trial (CSPPT), conducted from May 2008 to August 2013. The primary outcome was development of CKD, defined as a decrease in eGFR of ≥30% and to a level of <60 mL/min/1.73 m²; or end stage renal disease.

RESULTS

The median follow-up duration was 4.4 years. Overall, the association between SAlb levels and risk of the primary outcome followed a U-shape. The risk of CKD development significantly decreased with the increment of SAlb (per g/L: OR = 0.92; 95% CI: 0.88-0.96) in participants with SAlb <51.4 g/L, and increased with the increment of SAlb (per g/L: OR = 1.06; 95%CI: 1.01-1.11) in participants with SAlb ≥51.4 g/L. Moreover, in participants with SAlb <51.4 g/L, the association between SAlb and CKD development remained significant in participants without proteinuria (per g/L: OR = 0.93; 95% CI: 0.88-0.99). The association between SAlb and CKD development was not significantly modified by age, sex, folic acid treatment, proteinuria, systolic blood pressure (SBP) at baseline and time-averaged SBP during the treatment period (all P-interactions>0.05).

CONCLUSIONS

There was a U-shaped association between SAlb levels and risk of CKD development among general hypertensive patients with normal renal function and without CVD, with a turning point at about 51.4 g/L.

Age-differential association between serum uric acid and incident hypertension

Increasing evidence suggests a positive association between the serum uric acid (SUA) level and incident hypertension. However, the association has been inconsistent based on age, sex, body mass index, and lipid profiles. Thus, we investigated whether there is an interaction between SUA and other risk factors on incident hypertension in the Korean general population. In this study, 808 participants aged 40-79 years were included. They were free of hypertension and major cardiovascular disease at baseline. Incident hypertension was defined as systolic blood pressure (SBP) ≥ 140 mmHg, diastolic blood pressure (DBP) ≥ 90 mmHg, or use of antihypertensive medication. To investigate whether the association between SUA and incident hypertension is modified by other risk factors for hypertension, a generalized linear model and Z test were used. During the mean follow-up of 3.3 years, 11.5% of men and 10.7% of women developed hypertension. The association between SUA and incident hypertension was inconsistent according to participant age (p for interaction = 0.009). The association between SUA level and incident hypertension was positively significant among people aged < 55 years (relative risk 1.74 per 1.0 mg/dL of SUA; p = 0.002), but there was no significant association among people aged ≥ 55 years (p = 0.894). In a secondary analysis, the SUA level was not associated with an increase in SBP, but positively associated with DBP. We observed an age-differential association between SUA level and incident hypertension among Koreans. An increased SUA level can be a trigger for hypertension through early vascular changes in the middle-aged population.

Metabolic syndrome and hip fracture: Epidemiology and perioperative outcomes

INTRODUCTION

Hip fractures and metabolic syndrome (MetS) are becoming major global healthcare burdens as populations age. This study sought to determine the impact of MetS in hip fracture patients on perioperative outcomes following operative fixation or arthroplasty.

METHODS

Data from the 2004-2014 Nationwide Inpatient Sample was used to select 3,348,207 discharges with hip fracture. MetS patients were identified by having at least 3 of 4 component comorbidities: hypertension, dyslipidemia, obesity, and diabetes. Logistic regression was used to estimate odds ratios for the association between MetS and perioperative outcomes adjusted for age, gender, race, payer status, and comorbidities.

RESULTS

Overall, 32% of hip fracture patients were treated with open reduction internal fixation (ORIF), 28% hemiarthroplasty (HA), 18% closed reduction with internal fixation (CRPP), and 3% primary total hip arthroplasty (THA). The remaining 19% of cases were either treated via unspecified procedure of hip repair (9%), managed non-operatively (2%), underwent multiple procedures during the hospital stay (6%), or the surgical procedure data was missing (2%) and were excluded from procedural analyses. The prevalence of MetS was 7.9% and increased among minorities, patients treated at urban hospitals, with comorbidities (heart failure, kidney disease, peripheral vascular disease), and with Medicare coverage. MetS was associated with increased odds of any adverse event (p < 0.0001), specifically: acute renal failure, myocardial infarction, acute posthemorrhagic anemia. MetS was also associated with increased LOS (p < 0.0001) and increased total charges (p < 0.0001). However, MetS was associated with reduced odds of postoperative pneumonia, deep vein thrombosis and pulmonary embolism, surgical site infection, septicemia, and in-hospital mortality (p < 0.0001). The above associations were maintained for MetS patients stratified according to their treatment groups: HA, CRPP, and ORIF.

CONCLUSIONS

MetS is associated with increased odds of complications in hip fracture patients but decreased odds of in-hospital mortality. This may be related to patients' nutritional status and catabolic states in the perioperative period.

The Effect of Nutrition and Sleep Habits on Predisposition for Metabolic Syndrome in Greek Children

PURPOSE

To investigate the effect of lifestyle habits in childhood Metabolic Syndrome (MTS).

DESIGN AND METHODS

Descriptive correlation study with 480 participants (5-12 years old) using a specially designed questionnaire was conducted. Anthropometric and biochemical analyses were performed.

RESULTS

Fifteen percent of children exhibited predisposition for MTS. Regarding sleep habits, logistic regression analysis (LRA) showed that hour of sleep -before 22:00- was associated with decreased waist circumference (WC%) (p = .026). Midday siesta was negatively correlated with systolic (SBP) (p = .001) and diastolic blood pressure (DBP) (p = .046). In children without MTS, lack of sleep and night time sleep was positively correlated with DBP (p = .044) and fasting blood glucose (FBG) (p = .005). Regarding nutrition habits, fast food consumption was positively correlated with SBP (p = .006) and meat consumption was positively correlated with both Body Mass Index% (BMI%) (p = .038) and WC% (p = .023). LRA showed that fruit (p = .001) and legume (p = .040) consumption was associated with decreased FBG; fish consumption with decreased Low Density Lipoprotein (LDL) cholesterol (p = .031), vegetable (p = .054) and cereal consumption (p = .012) with decreased DBP. In children with MTS, fruits were associated with increased FBG (p = .034). In children without MTS, meat consumption was associated with increased LDL (p = .024), cereal with increased WC% (p = .002) and olive products with increased High Density Lipoprotein (HDL) cholesterol and BMI% (p = .037).

CONCLUSIONS

The adoption of both balanced diet and sleep habits seemed to be crucial for the prevention of MTS.

PRACTICE IMPLICATIONS

Clinical health nurses could develop and implement preventive intervention programs in order to avoid metabolic complications in adulthood.

Baseline level and change in serum albumin concentration and the risk of incident type 2 diabetes

AIMS

We aimed to determine whether baseline level and change in serum albumin concentration are predictive of future development of type 2 diabetes (T2D).

METHODS

A total of 15,428 subjects (8764 men and 6664 women) without diabetes at baseline, aged 21-88years (mean age of 51.0years), were enrolled from a health screening program.

RESULTS

During the 5-year follow-up period, a total of 599 incident cases (3.9%) of T2D developed. Higher baseline serum albumin concentration was associated with increased T2D risk, independent of age, sex, or body mass index; however, this association was confounded and was not significant after further adjustment for other T2D risk factors. Compared with subjects in the lowest tertile of change in serum albumin concentration, subjects in the highest tertile showed a lower risk for T2D development, independent of risk factors for T2D and baseline serum albumin concentration [OR (95% CI), 0.30 (0.21-0.43), p for trend <0.001].

CONCLUSION

Higher baseline serum albumin concentration was not an independent risk factor of future T2D, whereas an increase in serum albumin concentration was independently associated with a lower diabetes risk.

A comparative research on obesity hypertension by the comparisons and associations between waist circumference, body mass index with systolic and diastolic blood pressure, and the clinical laboratory data between four special Chinese adult groups

BACKGROUND

The obesity-hypertension pathogenesis is complex. From the phenotype to molecular mechanism, there is a long way to clarify the mechanism. To explore the association between obesity and hypertension, we correlate the phenotypes such as the waist circumference (WC), body mass index (BMI), systolic blood pressure (SB), and diastolic blood pressure (DB) with the clinical laboratory data between four specific Chinese adult physical examination groups (newly diagnosed untreated just-obesity group, newly diagnosed untreated obesity-hypertension group, newly diagnosed untreated just-hypertension group, and normal healthy group), and the results may show something.

OBJECTIVE

To explore the mechanisms from obesity to hypertension by analyzing the correlations and differences between WC, BMI, SB, DB, and other clinical laboratory data indices in four specific Chinese adult physical examination groups.

METHODS

This cross-sectional study was conducted from September 2012 to July 2014, and 153 adult subjects, 34 women and 119 men, from 21 to 69 years, were taken from four characteristic Chinese adult physical examination groups (newly diagnosed untreated just-obesity group, newly diagnosed untreated obesity-hypertension group, newly diagnosed untreated just-hypertension group, and normal healthy group). The study was approved by the ethics committee of Hangzhou Center for Disease Control and Prevention. WC, BMI, SB, DB, and other clinical laboratory data were collected and analyzed by SPSS.

RESULTS

Serum levels of albumin (ALB)，alanine aminotransferase (ALT), low density lipoprotein cholesterol (LDLC), triglyceride (TG), high density lipoprotein cholesterol (HDLC), alkaline phosphatase (ALP), uric acid (Ua), and TC/HDLC (odds ratio) were statistically significantly different between the four groups. WC statistically significantly positively correlated with BMI, ALT, Ua, and serum levels of glucose (GLU), and TC/HDLC, and negatively with ALB, HDLC, and serum levels of conjugated bilirubin (CB). BMI was statistically significantly positively related to ALT, Ua, LDLC, WC, and TC/HDLC, and negatively to ALB, HDLC, and CB. DB statistically significantly positively correlated with ALP, BMI, and WC. SB was statistically significantly positively related to LDLC, GLU, serum levels of fructosamine (FA), serum levels of the total protein (TC), BMI, and WC.

CONCLUSION

The negative body effects of obesity are comprehensive. Obesity may lead to hypertension through multiple ways by different percents. GGT, serum levels of gamma glutamyltransferase; ALB, serum levels of albumin; ALT, serum levels of alanine aminotransferase; LDLC, serum levels of low density lipoprotein cholesterol; TG, serum levels of triglyceride; HDLC, serum levels of high density lipoprotein cholesterol; FA, serum levels of fructosamine; S.C.R, serum levels of creatinine; IB, serum levels of indirect bilirubin; ALP, serum levels of alkaline phosphatase; CB, serum levels of conjugated bilirubin; UREA, Urea; Ua, serum levels of uric acid; GLU, serum levels of glucose; TC, serum levels of the total cholesterol; TB, serum levels of the total bilirubin; TP, serum levels of the total protein; TC/HDLC, TC/HDLC ratio.

Increase in serum albumin concentration is associated with prediabetes development and progression to overt diabetes independently of metabolic syndrome

Aim

Serum albumin concentration is associated with both type 2 diabetes and metabolic syndrome (MetS). We sought to investigate whether baseline serum albumin and change in serum albumin could be independent risk factors for prediabetes in subjects without MetS. We further examined the effect of serum albumin on progression to overt diabetes in subjects who developed prediabetes.

Methods

Among 10,792 participants without diabetes and MetS who consecutively underwent yearly health check-ups over six years, 9,807 subjects without incident MetS were enrolled in this longitudinal retrospective study. The risk of developing prediabetes (impared fasting glucose or hemoglobin A1c) was analyzed according to baseline and percent change in serum albumin concentration using Cox regression analysis. Serial changes in serum albumin concentration were measured from baseline to one year before prediabetes diagnosis, and then from the time of prediabetes diagnosis to progression to overt diabetes or final follow-up.

Results

A total of 4,398 incident cases of prediabetes developed during 35,807 person-years (median 3.8 years). The hazard ratio for incident prediabetes decreased as percent change in serum albumin concentration (quartiles and per 1%) increased in a crude and fully adjusted model. However, baseline serum albumin concentration itself was not associated with prediabetic risk. Serum albumin levels kept increasing until the end of follow-up in prediabetic subjects who returned to normal glycemic status, whereas these measures did not change in prediabetic subjects who developed type 2 diabetes. Serum albumin concentration measured at the end of follow-up was the highest in the regression group, compared to the stationary (p = 0.014) or progression groups (p = 0.009).

Conclusions

Increase in serum albumin concentration might protect against early glycemic deterioration and progression to type 2 diabetes even in subjects without MetS.

Serum albumin concentration and incident type 2 diabetes risk: new findings from a population-based cohort study

AIMS/HYPOTHESIS

Serum albumin concentrations may be associated with future risk of type 2 diabetes, but the epidemiological evidence is limited and uncertain. We prospectively assessed the association between baseline values of serum albumin and incident type 2 diabetes risk in the Kuopio Ischaemic Heart Disease population-based cohort study.

METHODS

We analysed the data of 1,785 men aged 42-61 years with no known history of diabetes at baseline. Participants' serum albumin concentrations were measured at baseline. HRs and 95% CIs for type 2 diabetes events were subsequently assessed.

RESULTS

During a mean follow-up of 20.4 years, 382 participants developed diabetes. Serum albumin concentrations were weakly correlated with several established risk factors for diabetes. Serum albumin was approximately linearly associated with type 2 diabetes risk. In analyses adjusted for several conventional risk factors, the HR for type 2 diabetes per 1 SD increase in serum albumin was 1.15 (95% CI 1.03, 1.28; p = 0.016), which persisted after further adjustment for triacylglycerol, C-reactive protein, γ-glutamyltransferase, estimated glomerular filtration rate and total energy intake (HR 1.15; 95% CI 1.02, 1.29; p = 0.018). The findings were generally consistent across several clinical subgroups. Addition of information on serum albumin to a diabetes risk prediction model containing conventional risk factors led to no significant change in C-index (0.0126; 95% CI -0.0055, 0.0306; p = 0.17).

CONCLUSIONS/INTERPRETATION

A near linear, positive and independent association was found between serum albumin and type 2 diabetes, but this did not improve event discrimination. Further work is warranted to evaluate the causal relevance of these findings.

Association between serum 25-hydroxyvitamin D level and insulin resistance in a rural population

PURPOSE

A low serum 25-hydroxyvitamin D [25(OH)D] level in the blood has been correlated with an increased risk of diabetes mellitus; however, the association between serum 25(OH)D level and insulin resistance has not been established in a Korean rural population. The aim of this study was to investigate the independent association between serum 25(OH)D level and insulin resistance in rural Korean adults.

MATERIALS AND METHODS

This study used data from the Korean Genome Epidemiology Study-Kangwha Study. In the 2011 study, 1200 adults completed health examinations. In an ancillary study, serum 25(OH)D level was measured in a subsample (n=813). After excluding those taking vitamin D supplements, a cross-sectional analysis was carried out on 807 participants (324 men and 483 women) aged 40 to 89 years old. Measured from overnight fasting blood samples, glucose and insulin levels were used to calculate the homeostasis model assessment for insulin resistance (HOMA-IR). Measures of glucose, insulin, and HOMA-IR were log-transformed for parametric tests.

RESULTS

Serum 25(OH)D level was inversely associated with HOMA-IR (β=-0.003, p=0.039) in a univariate analysis. However, the association was not significant after adjustment for sex and age (β=-0.002, p=0.123) or after adjustment for sex, age, body mass index, smoking status, alcohol intake, and regular exercise (β=-0.003, p=0.247).

CONCLUSION

Our findings suggest that vitamin D is not independently associated with insulin resistance in Korean men and women.