Body mass index versus surrogate measures of central adiposity as independent predictors of mortality in type 2 diabetes

A Body Shape Index (ABSI) as a risk factor for all-cause mortality among US adults with type 2 diabetes: evidence from the NHANES 1999-2018

Background and objective

A Body Shape Index (ABSI) serves as a potential indicator of fat distribution, offering a more reliable association with all-cause mortality compared to overall adiposity. The present cohort study aims to explore the relationship between ABSI and all-cause mortality in US adults with Type 2 Diabetes (T2D).

Methods

For this cohort study, we extracted information on 5,461 US adults with T2D from the National Health and Nutrition Examination Survey (NHANES) and the NHANES Linked Mortality File. Trends in ABSI from 1999 to 2018 were calculated and analyzed using partial Mann-Kendall tests. To assess the relationship between ABSI and all-cause mortality, as well as the robustness of the association results, we employed weighted restricted cubic splines (RCS), weighted Cox proportional hazards models, sensitivity analyses, and stratified analyses. Additionally, we conducted time-dependent receiver operating characteristic (ROC) curve analysis to evaluate ABSI's predictive capability for all-cause mortality over 3, 5, and 10 years.

Results

Among US adults with Type 2 Diabetes (T2D), the mean ABSI gradually increased from 0.08333 to 0.08444 between 1999 and 2018. Following a median follow-up period of 90 months, 1,355 deaths (24.8% of the participants) occurred due to all causes. A left J-shaped association was observed between ABSI and all-cause mortality, with a 39% increased risk among US adults with T2D who had an ABSI below 0.08105 after full adjustment.

Conclusion

Our research has demonstrated a significant association between an elevated ABSI and the risk of all-cause mortality among US adults with T2D. These findings support the potential use of ABSI as a noninvasive tool to estimate mortality risk among US adults with T2D.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-025-01570-3.

Association of cardiometabolic index with gallstone disease and insulin resistance based on NHANES data

BACKGROUND

Cardiometabolic index (CMI) is an index integrating visceral obesity and dyslipidemia. This study intends to scrutinize the connection between CMI and gallstone disease (GSD) and to elucidate the association between CMI and insulin resistance (IR) in patients with GSD.

METHODS

To explore the potential nonlinear association and determine the inflection point, a restricted cubic spline (RCS) analysis was performed. Following categorization of CMI based on the identified inflection point, multivariate logistic regression models, subgroup analyses, and interaction tests were utilized to assess the connection between CMI and GSD, as well as between CMI and IR in GSD patients. The homeostasis model assessment for IR (HOMA-IR) and triglyceride-glucose (TyG) index was applied to evaluate IR. Spearman analysis was implemented to investigate the connection between CMI and HOMA-IR. The predictive performance of each indicator was evaluated by the receiver operating characteristic (ROC) curve and the area under the curve (AUC).

RESULTS

The study included 2311 individuals, with a GSD prevalence of 10.90%. RCS analysis revealed a nonlinear positive correlation between CMI and GSD (nonlinear P < 0.001), as well as between CMI and IR (nonlinear P < 0.001). In the fully adjusted multivariable logistic regression analysis of covariates, compared with the low-category CMI group, the high-category CMI was significantly associated with the risk of GSD (OR = 1.547, 95% CI: 1.143-2.092, P = 0.005), IR (OR = 4.990, 95% CI: 2.517-9.892, P < 0.001). Subgroup analysis demonstrated that the correlation between CMI and GSD was stronger in females. Spearman correlation analysis showed a positive association between CMI and HOMA-IR in GSD patients (r = 0.548, P < 0.001). The ROC curve demonstrated the predictive performance of the CMI model for GSD (AUC = 0.743), which was superior to conventional indicators such as Body Mass Index and Waist Circumference; the predictive performance of CMI (AUC = 0.772) for IR was consistent with that of TyG (AUC = 0.772).

CONCLUSION

Our research demonstrates that CMI exhibits a nonlinear positive correlation with the incidence of GSD and IR. This suggests that CMI may serve as a novel and valuable indicator for further investigating the intricate relationships among metabolic syndrome, obesity, and GSD.

Value of the conicity index as an indicator of abdominal obesity in predicting cardiovascular disease and all-cause mortality risk in patients with diabetes based on NHANES data from 1999-2018

OBJECTIVE

The mortality risk among patients with diabetes is increasingly severe, yet the relationship between obesity and mortality risk in these patients remains controversial. This study evaluated the Conicity index (C-index), an indicator of abdominal obesity, to determine its value in predicting cardiovascular disease (CVD) and all-cause mortality in patients with diabetes.

METHODS

This cross-sectional study utilized NHANES 1999-2018 data. Patients were grouped into quartiles based on the C-index. The relationship between the C-index and mortality risk was assessed using Cox proportional hazards regression models and restricted cubic spline (RCS) analysis.

RESULTS

A total of 7694 patients with diabetes were included in the study. The obesity rate was 55.7 %, with an average follow-up duration of 88 months. During this period, 588 CVD deaths and 2094 all-cause deaths occurred. Higher C-index quartiles were associated with increased mortality risks, with hazard ratios for all-cause mortality ranging from 1.00 to 2.29 and for CVD mortality from 1.00 to 2.23. Unadjusted RCS analysis showed a linear positive correlation between the C-index and mortality risks. After adjusting for confounding factors, a non-linear positive correlation was observed between the C-index and all-cause mortality risk, particularly when the C-index exceeded 1.40. Subgroup analysis revealed that the relationship between the C-index and all-cause mortality was more significant in men and nonobese patients.

CONCLUSIONS

The C-index is a valuable predictor of mortality in patients with diabetes. A C-index above 1.40, being male, and being nonobese are associated with a more significant risk of all-cause mortality.

Cardiometabolic index as a predictor of gallstone risk: evidence from NHANES 2017-2020

BACKGROUND

The Cardiometabolic Index (CMI), a composite marker integrating lipid profiles (triglycerides-to-HDL-C ratio) and abdominal obesity (waist-to-height ratio), we aimed to assess its association with gallstone prevalence.

METHODS

We analyzed data from 2,692 participants in the NHANES 2017-2020 dataset. Gallstones were identified through self-reported data, which may introduce bias in the diagnosis. This limitation should be considered when interpreting the results. Logistic regression modelling, smoothed curve fitting and threshold effect analysis assessed the association between CMI and gallstones.

RESULT

Higher CMI was significantly associated with an increased risk of gallstones (OR = 1.90, 95% CI: 1.37-2.62, P < 0.0001). A threshold effect was observed at CMI = 0.85, below which risk increased significantly (OR = 2.62, 95% CI:1.34-5.12, P = 0.0049), but became non-significant above this value. The association was stronger in women.

CONCLUSION

Our findings support the use of CMI as a potential predictive marker for gallstone risk, suggesting its integration into clinical assessments for early detection and prevention.

Body Mass Index and Risk of All-Cause and Cardiovascular Disease Mortality in Patients With Type 2 Diabetes Mellitus

CONTEXT

The correlations between body mass index (BMI) and risk of all-cause and cardiovascular disease (CVD) mortality in patients with type 2 diabetes mellitus (T2DM) are still controversial.

OBJECTIVE

To explore the correlation between BMI and the risk of all-cause and CVD mortality in patients with T2DM.

METHODS

The data sources China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, PubMed, Web of Science, Embase, and The Cochrane Library were searched up until May 25, 2024. After adjusting for confounding factors, the original study on the association between BMI and all-cause and CVD mortality in patients with T2DM was analyzed. Number of all-cause and CVD mortality events, BMI, and basic characteristics were extracted.

RESULTS

Twenty-eight papers with a total of 728 321 participants were finally included. Compared to normal-weight patients with T2DM, the risk of all-cause (HR = 1.61; 95% CI [1.51, 1.72]; P = .000) and CVD (HR = 1.31; 95% CI [1.10, 1.54]; P = .002) mortality were increased in underweight patients; however, they were reduced (HR = 0.85; 95% CI [0.81, 0.89]; P = .000) and (HR = 0.86; 95% CI [0.78, 0.96]; P = .007), respectively in patients with overweight. Also, there were significant reductions in the risk of all-cause (HR = 0.85; 95% CI [0.78, 0.92]; P = .000) and CVD (HR = 0.81; 95% CI [0.74, 0.89]; P = .000] mortality in patients with mild obesity. The difference in the risk of all-cause mortality (HR = 0.98; 95% CI [0.80, 1.21]; P = .881) in patients with moderate obesity was not statistically significant.

CONCLUSION

We found that there were correlations between BMI and the risk of all-cause and CVD mortality in patients with T2DM. The obesity paradox remains.

The combined impact of BMI and ABSI on all-cause mortality among American adults with diabetes

OBJECTIVE

Previous studies have emphasized the independent effects of anthropometric indices-including body mass index (BMI), A Body Shape Index (ABSI), waist-to-height ratio (WHtR), body roundness index (BRI), and Conicity Index-on mortality. However, their combined impact, especially in diabetic populations with distinct obesity patterns, has been less frequently explored. This study investigates both the independent and combined effects of these anthropometric indices on mortality in diabetic Americans and compares their individual and combined diagnostic value.

METHODS

A nationally representative cohort study was conducted using NHANES data (2005-2018), including 6,572 diabetic adults. Weighted Cox proportional hazards models and restricted cubic splines were applied to evaluate the independent and combined associations of anthropometric indices (BMI, ABSI, WHtR, BRI, and Conicity Index) with all-cause mortality. The weighted receiver operating characteristic (ROC) curve was used to assess the diagnostic value of individual anthropometric indices and their combinations in predicting mortality.

RESULTS

Among all the anthropometric indices, ABSI exhibited the strongest independent association with all-cause mortality, outperforming other measures such as BMI, WHtR, BRI, and Conicity Index. A clear linear relationship was identified, with higher ABSI tertiles consistently linked to an increased risk of mortality. Notably, within each BMI tertile, ABSI effectively differentiated mortality risk, particularly in the highest tertile. Furthermore, ABSI demonstrated the highest predictive performance among individual metrics (weighted AUC = 0.653) and showed further improvement when combined with BMI (weighted AUC = 0.669).

CONCLUSION

BMI and ABSI collectively provide a comprehensive evaluation of mortality risk in diabetic populations, capturing the synergistic effects of general and central obesity. These findings highlight the importance of integrating BMI and ABSI into risk assessments to identify high-risk individuals and guide targeted interventions for reducing mortality.

The synergistic effect of the triglyceride-glucose index and a body shape index on cardiovascular mortality: the construction of a novel cardiovascular risk marker

BACKGROUND

Insulin resistance, represented by increased triglyceride-glucose (TyG) index levels, shows interplay with visceral obesity and together promotes cardiovascular diseases and mortality. However, significant controversies exist regarding whether modified TyG indices, such as TyG-BMI, TyG-WC, and TyG-WHtR, outperform the TyG index in predicting cardiovascular outcomes. We aimed to explore whether there was a synergistic effect of a body shape index (ABSI), a better parameter reflecting visceral obesity, and the TyG index on cardiovascular mortality.

METHODS

We analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2001-2018 of 17,329 individuals. The associations of the TyG index and ABSI with cardiovascular mortality were investigated via Cox regression analysis and restricted cubic splines. Receiver operating characteristic (ROC) curve analysis was performed to compare the predictive value. Mediation analysis was used to explore the potential mediator.

RESULTS

A total of 673 (3.9%) cardiovascular deaths occurred during a median follow-up of 8.92 years. Individuals with high TyG and high ABSI (TyG > 9.04 and ABSI > 0.085) were at the highest cardiovascular mortality risk both in individuals with (HR = 1.714, 95% CI 1.123-2.616) and without diabetes (HR = 1.402, 95% CI 1.003-1.960), suggesting a synergistic effect. Next, we multiplied these two indicators and established TyG-ABSI. It showed a J-shaped relationship and a positive linear relationship with cardiovascular mortality in individuals with and without diabetes, respectively. Arterial stiffness, represented by estimated pulse wave velocity, partially mediated the effect of TyG-ABSI on cardiovascular mortality, with a mediation proportion of 42.7%. The predictive value of TyG-ABSI was greater than that of the TyG index, TyG-BMI, TyG-WC, and TyG-WHtR (Harrell's C-index: 0.710 vs 0.623 vs 0.539 vs 0.612 vs 0.622, all p < 0.001).

CONCLUSIONS

The simultaneous assessment of the TyG index and ABSI revealed a synergistic effect on cardiovascular mortality. We recommended the use of TyG-ABSI instead of the TyG index and other modified TyG indices in cardiovascular risk assessment.

Waist-to-calf circumference ratio as a potential indicator of diabetes risk: results from the Longevity Check-Up (Lookup) 8

Diabetes is a prevalent metabolic condition with substantial health and economic impacts. Therefore, effective and accessible indicators are essential for early detection and prevention. This study investigates the link between the waist-to-calf circumference ratio (WCR) and diabetes risk in a large cohort from the Longevity Check-Up (Lookup) 8+ Study. The present investigation is a retrospective cross-sectional study. Diabetes was defined either as self-reported diagnosis, or fasting plasma glucose equal to or greater than 126 mg/dL, or random plasma glucose equal to or greater than 200 mg/dL. The WCR was calculated by dividing waist circumference by calf circumference. A total population of 8900 participants (mean age 57.1 ± 14.8 years, 55% women) was included in the study. The prevalence of diabetes was 9.4%. Mean WCR displayed a significant trend (p for trend < 0.001), and the analysis of covariance (ANCOVA) revealed significant differences among the normal, pre-diabetes, diabetes groups. Unadjusted logistic regression showed a positive association between higher WCR and diabetes, which remained significant in the adjusted models. Receiver operating characteristic curve analysis indicated that WCR had a higher area under the curve compared to waist circumference alone, with cut-off values of 2.35 for men and 2.12 for women providing high sensitivity (91% for men, 92% for women) and specificity (74% for men, 75% for women). Our study introduces WCR as a novel, simple, and cost-effective anthropometric measure for identifying individuals at risk of diabetes, suitable for clinical use, especially in resource-limited settings.

Association between sleep duration and three obesity indicators among middle-aged and elderly adults: findings from the NHANES 2005-2014

Objective

Obesity has emerged as a worldwide problem. In recent years, it has been verified that there is an association between sleep duration and obesity indicators. This provides a new approach to control obesity. In this study, the relationship between duration of sleep and body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) among Americans ≥45 years old was investigated.

Methods

Data was collected from the National Health and Nutrition Examination Survey (NHANES) between 2005 and 2014. The link between sleep duration and obesity indicators was analysed using multiple regression models and weighted smoothed curve fitting. Subgroup analysis was conducted to assess the consistency of the connection between sleep duration and obesity indicators across various groups.

Results

This study involved 7,118 males and 7,265 females, with an average age of 62.09. After total adjustment, sleep duration was negatively correlated with BMI (β = -0.19, 95%CI: -0.26, -0.12), WC (β = -0.36, 95%CI: -0.53, -0.19) and WHtR (β = -0.27, 95%CI: -0.38, -0.17). Subgroup analyses revealed more significant negative associations between sleep duration and BMI, WC, and WHtR among non-Hispanic White participants, and those without diabetes and hypertension.

Conclusion

Sleep duration was significantly negatively associated with BMI, WC, and WHtR, suggesting that longer sleep duration may contribute to lower obesity indicators in middle-aged and elderly Americans. Subgroup analysis showed that their negative correlation differed between races, diabetes, or hypertension status. However, additional prospective studies are required to validate these findings and investigate potential causal relationships.

Association of weight-adjusted-waist index with all-cause and cardiovascular mortality in individuals with diabetes or prediabetes: a cohort study from NHANES 2005-2018

Weight-adjusted waist index (WWI) is a new marker of central obesity. This study explored the association of WWI with all-cause and cardiovascular disease (CVD) mortality in individuals with diabetes or prediabetes. 6551 participants with diabetes or prediabetes from the National Health and Nutrition Examination Survey (NHANES) records between 2005 and 2018 were included. The association of WWI with all-cause and CVD mortality was assessed using Kaplan-Meier survival analysis, Cox proportional hazards model (Cox regression), and restricted cubic spline (RCS). The predictive value of WWI for mortality was analyzed using time-dependent receiver operating characteristic curves (ROC). There were 1083 all-cause deaths and 360 CVD deaths. Multivariable-adjusted Cox regression analyses showed WWI was positively correlated with the risk of all-cause and CVD mortality in subjects with diabetes or prediabetes. Multivariate-adjusted RCS analyses showed a linear and positive correlation of WWI with all-cause mortality risk, and a nonlinear relationship with CVD mortality, with a threshold of 12.35. The area under the curve (AUC) for 3, 5, and 10-years survival for all-cause mortality was 0.795, 0.792, and 0.812, respectively, and for CVD mortality was 0.815, 0.833, and 0.831, respectively. WWI is a valuable predictor of all-cause mortality risk in patients with diabetes and prediabetes, and a valuable predictor of CVD mortality risk when patients with diabetes and prediabetes are considered as a whole.

Association between cardiometabolic index and kidney stone from NHANES: a population-based study

Purpose

The Cardiometabolic Index (CMI) is a novel marker of visceral obesity and dyslipidemia. Our study aimed to explore the association between CMI and kidney stones among US adults.

Methods

This cross-sectional study was conducted among adults with complete records of CMI and kidney stones information from the 2011 to 2018 National Health and Nutrition Examination Survey (NHANES). Inverse probability treatment weighting (IPTW) was used to balance the baseline characteristics of the study population. The independent relationship between CMI and kidney stones was evaluated using IPTW-adjusted multivariate logistic regression, restricted cubic splines (RCS), and subgroup analysis.

Results

A total of 9,177 participants, with an average CMI of 0.72 (0.99), were included in this study. The IPTW-adjusted logistic regression revealed that CMI was an independent risk factor for kidney stones. The adjusted odds ratio (OR) for kidney stones were 1.39 (95% CI: 1.24 - 1.56, P < 0.001) for the second CMI tertile and 1.31 (95% CI: 1.17 - 1.47, P < 0.001) for the third CMI tertile, compared with the first CMI tertile. A linear relationship between CMI levels and kidney stone risk was observed in the RCS analysis. Subgroup analysis showed that the association between CMI levels and kidney stone risk remained stable across groups.

Conclusions

A positive association between CMI level and the risk of kidney stones was observed among US adults in our study. Further large-scale prospective studies are needed to validate our findings.

Association of weight-adjusted waist index and diabetic kidney disease in type 2 diabetes mellitus

Objective

The aim of this study was to investigate the relationship between weight-adjusted-waist index (WWI) and diabetic kidney disease in individuals afflicted with type 2 diabetes.

Methods

Comprehensive data were ascertained from the National Health and Nutrition Examination Survey in 2013-March 2020. Weighted univariate, multivariate logistic regression models, subgroup analyses and tests for interaction were performed. Additionally, we employed smooth curve fitting to assess linear correlations and the threshold effects were calculated by applying a binary linear regression model. Breakpoints are identified by a model with maximum likelihood ratio and a two-step recursive approach. Receiver operating characteristic curve (ROC) along with the area under the curve (AUC) value predict the capability of WWI and body mass index for diabetic kidney disease.

Results

A total of 10,661 individuals diagnosed with type 2 diabetes were included, and the overall prevalence of diabetic kidney disease was 20.74%. WWI exhibited a positive correlation with the likelihood of diabetic kidney disease in type 2 diabetes patients (OR: 1.17, 95% CI: 1.03-1.33). The results of subgroup analysis showed significant interaction for gender (P < 0.05). Among female patients, U-shaped correlations were observed with a breakpoint at 11.48. Additionally, weight-adjusted waist index (AUC = 0.664) proved to be a more effective predictor of diabetic kidney disease compared to body mass index (AUC = 0.555).

Conclusion

In patients with type 2 diabetes, increased weight-adjusted-waist index is implicated with an increased risk of diabetic kidney disease. WWI can be used as a new anthropometric index to predict diabetic kidney disease, and its predictive ability is stronger than body mass index.

Obesity indices and the risk of total and cardiovascular mortality among people with diabetes: a long-term follow-up study in Taiwan

BACKGROUND

The association between obesity indicators and mortality in individuals with diabetes remains unclear, and data on cardiovascular mortality are scarce. Therefore, we investigated the associations between the five adiposity indices and both all-cause and cardiovascular mortality in patients with diabetes.

METHODS

This cohort study included 34,686 adults with diabetes who underwent a standard health-screening program between 1996 and 2017 in Taiwan. The dates and causes of death till January 2022 were retrieved from the National Death Registry. Cox proportional hazards models were used to calculate the hazard ratios (HR) and 95% confidence intervals (CI) for all-cause and cardiovascular mortality in relation to body mass index (BMI), waist circumference, waist-hip ratio (WHR), body fat percentage (BF%), and A Body Shape Index (ABSI), using the third quintile as the reference group.

RESULTS

During a median follow-up of 15 years, there were 8,324 deaths, of which 1,748 were attributed to cardiovascular disease. After adjusting for demographics, lifestyle factors and comorbidities, ABSI was associated with all-cause mortality in an exposure-response manner; the HR (95% CI) for first and fifth vs. third quintile was 0.78 (0.69-0.89) and 1.24 (1.14-1.35), respectively. A similar but weaker exposure-response relationship was found between WHR and mortality. People with a lower BMI and BF% had an increased risk of mortality (HR [95% CI] for the first vs. third quintiles, 1.33 [1.22, 1.44] and 1.42 [1.30, 1.56], respectively). No association was observed between waist circumference categories and risk of mortality. Similar results were observed for the association of BF%, waist circumference, and ABSI with cardiovascular mortality. However, no significant association was observed between BMI and cardiovascular mortality. The association between WHR and cardiovascular mortality was stronger than that between WHR and all-cause mortality.

CONCLUSIONS

ABSI demonstrated a consistent exposure-response relationship with both all-cause and cardiovascular mortality in this Asian cohort with diabetes. Our findings highlight the importance of monitoring ABSI, a surrogate index of central adiposity, in patients with diabetes.

Association of body mass index and long-term mortality in patients from nationwide LIPIDOGRAM 2004-2015 cohort studies: no obesity paradox?

BACKGROUND

An obesity paradox has been described in relation to adverse clinical outcomes (e.g., mortality) with lower body mass index (BMI).

AIMS

We sought to evaluate the association between BMI and weight loss with long-term all-cause mortality in adult populations under the care of family physicians.

METHODS

LIPIDOGRAM studies were conducted in primary care in Poland in 2004, 2006, and 2015 and enrolled a total of 45,615 patients. The LIPIDOGRAM Plus study included 1627 patients recruited in the LIPIDOGRAM 2004 and repeated measurements in 2006 edition. Patients were classified by BMI categories as underweight, normal weight, overweight and class I, II, or III (obesity). Follow-up data up to December 2021 were obtained from the Central Statistical Office. Differences in all-cause mortality were analyzed using Kaplan‒Meier and Cox regression analyses.

RESULTS

Of 45,615 patients, 10,987 (24.1%) were normal weight, 320 (0.7%) were underweight, 19,134 (41.9%) were overweight, and 15,174 (33.2%) lived with obesity. Follow-up was available for 44,620 patients (97.8%, median duration 15.3 years, 61.7% females). In the crude analysis, long-term all-cause mortality was lowest for the normal-weight group (14%) compared with other categories. After adjusting for comorbidities, the highest risk of death was observed for the class III obesity and underweight categories (hazard ratio, HR 1.79, 95% CI [1.55-2.05] and HR 1.57, 95% CI [1.22-2.04]), respectively. The LIPIDOGRAM Plus analysis revealed that a decrease in body weight (by 5 and 10%) over 2 years was associated with a significantly increased risk of death during long-term follow-up-HR 1.45 (95% CI 1.05-2.02, p = 0.03) and HR 1.67 (95% CI 1.02-2.74, p < 0.001). Patients who experienced weight loss were older and more burdened with comorbidities.

CONCLUSIONS

Being underweight, overweight or obese is associated with a higher mortality risk in a population of patients in primary care. Patients who lost weight were older and more burdened with cardiometabolic diseases, which may suggest unintentional weight loss, and were at higher risk of death in the long-term follow-up. In nonsmoking patients without comorbidities, the lowest mortality was observed in those with a BMI < 25 kg/m2, and no U-curve relationship was observed.

Distribution and associated factors of intraocular pressure in the older population: Tehran Geriatric Eye Study

AIM

To determine the distribution and associated factors of intraocular pressure (IOP) in an Iranian elderly population 60 years of age and above.

METHODS

The present report is part of the Tehran Geriatric Eye study (TGES), a population-based cross-sectional study that was conducted on the residents of Tehran 60 years of age and above. The sampling was performed using multistage stratified random cluster sampling methods from 22 districts of Tehran, Iran. Demographic and history information, blood samples, and blood pressure were collected from all participants. Ocular examinations included measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, and slit-lamp biomicroscopy. The IOP was measured using Goldmann applanation tonometry (GAT). Corneal imaging and ocular biometry were performed using Pentacam AXL.

RESULTS

The data of 3892 eyes of 2124 individuals were analyzed for this report. The mean age of the study participants was 66.49±5.31y (range: 60 to 95y). The mean IOP was 15.2 mm Hg (95%CI: 15.1 to 15.4), 15.3 mm Hg (95%CI: 15.1 to 15.5) and 15.1 mm Hg (95%CI: 15.0 to 15.3) in all participants, males, and females, respectively. Of the study participants, 1.3% had an IOP of ≥20 mm Hg. The mean IOP increased from 15.1 mm Hg in the age group 60-64y to 16.3 mm Hg in the age group ≥80y. According to the final multiple GEE model, the IOP was statistically significantly higher in men than in women. All the studied age groups, except for the 75-79-year-old age group, had significantly higher IOP compared to the 60-64-year-old age group. The IOP was significantly higher in underweight compared to other body mass index groups. Moreover, the IOP had a statistically significant direct relationship with the mean corneal power (mean CP), central corneal thickness (CCT), and systolic blood pressure.

CONCLUSION

The present study presents the distribution of IOP in an Iranian elderly population. A higher IOP (within the range 14 to 17 mm Hg) is significantly associated with older age, male sex, high systolic blood pressure, increased mean CP, and CCT. These factors should be considered in the clinical interpretation of IOP.