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Care Publish Ahead of Print, published online September 17, 2010

THE IMPACT OF BODY INDEX AND THE ON THE RISK OF DIABETES IN MIDDLE-AGED MEN

Running title: BMI, metabolic syndrome and diabetes risk

Johan Ärnlöv, MD 1, 5, PhD, Johan Sundström, MD, PhD 2, 3; Erik Ingelsson, MD, PhD 1, 4; and Lars Lind, MD, PhD 2

1 Department of Public Health and Caring Sciences/Geriatrics, 2 Department of Medical Sciences, and 3 Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden;

4 Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; and 5 School of Health and Social Studies, Dalarna University, Falun, Sweden

Correspondence to: Johan Ärnlöv, MD, PhD Emailo: [email protected],

Submitted 17 May 2010 and accepted 10 September 2010.

This is an uncopyedited electronic version of an article accepted for publication in Diabetes Care. The American Diabetes Association, publisher of Diabetes Care, is not responsible for any errors or omissions in this version of the manuscript or any version derived from it by third parties. The definitive publisher- authenticated version will be available in a future issue of Diabetes Care in print and online at http://care.diabetesjournals.org.

Copyright American Diabetes Association, Inc., 2010 BMI, metabolic syndrome and diabetes risk

Objective: The existence of an obese sub-group, with a healthy metabolic profile and low diabetes risk, has been proposed. Yet, long term data is lacking. We aimed to investigate associations between combinations of (BMI)-categories and metabolic syndrome (MetS), and risk of in middle-aged men.

Research design and methods: At age 50, cardiovascular risk factors were assessed in 1675 participants without diabetes in the community-based ULSAM-study. According to BMI/MetS- status, they were categorized as normal weight (BMI<25 kg/m2) without MetS (NCEP-criteria, n=853), normal weight with MetS (n=60), (BMI 25-30 kg/m2) without MetS (n=557), overweight with MetS (n=117), obese (BMI>30 kg/m2) without MetS (n=28), and obese with MetS (n=60). We investigated the associations between BMI/MetS-categories at baseline and diabetes incidence.

Results: After 20 years, 160 participants had developed diabetes. In models adjusting for age, smoking, and physical activity, increased risks for diabetes were observed in normal-weight with MetS (odds ratio [OR] 3.28, 95%CI 1.38-7.81, p=0.007), overweight without MetS (OR 3.49, 95%CI 2.26-5.42, p<0.001), overweight with MetS (OR 7.77, 95%CI 4.44-13.62, p<0.001), obese without MetS (OR 11.72, 95%CI 4.88-28.16, p<0.001) and obese with MetS (OR 10.06, 95%CI 5.19-19.51, p<0.001), compared to normal-weight without MetS.

Conclusions: Overweight or obese men without MetS, were at increased risk for diabetes. Our data provide further evidence that overweight and in the absence of the MetS should not be considered a harmless condition.

igher body mass index (BMI) has MHO-hypothesis is not undisputed; it was consistently been associated with an recently reported that both overweight and Hincreased risk for type 2 diabetes.(1; obese middle-aged men without the MetS 2) One reason for the major impact of obesity were at increased risk for cardiovascular on the development of type 2 diabetes is that events and total mortality during 30 years of it often is accompanied by the metabolic follow-up.(7) syndrome (MetS) a cluster of , In a recent report from the Framingham Heart and .(3) Study, overweight or obese individuals In recent years it has been proposed that the without the MetS did not portray a association between BMI and the significantly increased risk for diabetes, while development of type 2 diabetes is more participants with the MetS were at complex than a mere a dose-response substantially higher risk for diabetes relationship.(4; 5) The existence of a regardless of BMI status.(8) However, in this metabolically healthy but obese phenotype previous study, the follow-up did not exceed (MHO) has been proposed, an obese sub- 7 years. Thus, data on the long-term impact of group with a healthy metabolic profile and different BMI/MetS-combinations and the with no increased risk for adverse outcomes risk of diabetes are still lacking. such as diabetes or .(4- We hypothesized that overweight and obesity, 6) It should, however, be noted that the regardless of MetS-status, as well as the

2 BMI, metabolic syndrome and diabetes risk

MetS, regardless of BMI-status, would be assayed by enzymatic techniques. Fasting associated with long-term increased risk for blood was determined by an oxidase diabetes. We tested our hypothesis by method and by radioimmunoassay. investigating the associations of combinations Supine systolic and diastolic blood pressures of BMI-categories and presence/absence of were measured twice in the right arm after 10 the MetS to long-term risk of type 2 diabetes minutes rest, and means were calculated. using data from a cohort study of middle-aged In the present study we used a modified men followed for 20 years. As a secondary version of the National Cholesterol Education aim, we investigated the association between Program (NCEP) definition of the MetS(3) combinations of BMI-categories and (Table 1). As circumference was only presence/absence of (IR) to measured in a subsample of the participants future risk of diabetes as some previous (n=480), the NCEP definition was modified investigators have defined MHO as obesity in by using a body mass index (BMI) cut-point the absence of insulin resistance.(4; 9; 10) instead of the NCEP waist circumference criterion (>102 cm). In the subsample with MATERIAL AND METHODS data on waist circumference, a waist Study Sample. In 1970 to 1973, all men born circumference of 102 cm corresponded to a in 1920 to 1924 and residing in the county of BMI of 29.4 kg/m2 in a linear regression Uppsala were invited to a health survey (at analysis (regression equation: BMI age 50) aimed at identifying risk factors for [kg/m2]=0.298 x waist circumference [cm] – cardiovascular disease; 82% of the invited 1.027). This BMI-cut point is similar to BMI men participated (n=2322). The cohort was cut-points used in previous modified NCEP reinvestigated after 10 and 20 years when the definitions of the metabolic subjects were approximately 60 and 70 years syndrome(12)BMI did not differ between this old, respectively. The design and selection subsample (25.2 kg/m2, SD 3.1) and the rest criteria for the cohort have been described of the cohort (25.0 kg/m2, SD 3.3, p=0.32). previously.(11) Participants were excluded for We used the homeostasis (HOMA, the following reasons: diabetes mellitus at [fasting glucose*fasting insulin]/22.5)(13) baseline (n=124), unavailable data on MetS and defined IR as HOMA-IR in the top components or covariates (n=523), leaving quartile of the distribution in participants 1675 men as the present study sample. Of without diabetes (> 3.43). Leisure time these, data on IR was available in 1375 physical activity was estimated using a participants. The baseline characteristics and questionnaire containing four physical the event rates of diabetes were similar in the activity categories; Sedentary, Moderate, present study sample compared to those Regular, and Athletic(11) participants who were excluded due to By defining normal weight as BMI < 25 missing data at baseline (data not shown). kg/m2, overweight as BMI 25-30 kg/m2, and Informed written consent was obtained and obesity as BMI > 30 kg/m2, we could the Uppsala University Ethics Committee categorize the participants as, normal weight approved the study. without MetS (n=853), normal weight with Baseline Examinations and MetS Definition. MetS (n=60), overweight without MetS The examination at age 50 has been described (n=557), overweight with MetS (n=117), in detail previously.(11) Blood samples for obese without MetS (MHO, n=28) and obese fasting concentrations were drawn in the with MetS (n=60). In secondary analyses, we morning after an overnight fast. Cholesterol also categorized participants according to and concentrations in serum were BMI/IR-categories: normal weight without IR

3 BMI, metabolic syndrome and diabetes risk

(n=652), normal weight with IR (n=103), RESULTS overweight without IR (n=389), overweight Baseline characteristics for the different BMI- with IR (n=172), obese without IR (n=21) and MetS categories are shown in Table 2. obese with IR (n=48). BMI/MetS-categories and type 2 diabetes Endpoint definitions. Diabetes was defined incidence. During the 20 year follow-up, 160 according to current WHO criteria using participants had developed type 2 diabetes. fasting concentrations of glucose (fasting The risk of diabetes was higher in the blood glucose ≥6.1 mmol/l at the baseline overweight and obesity categories and with investigation and 10-year reinvestigation prevalent MetS compared to normal weight [which corresponds to fasting plasma glucose individuals without the MetS in both crude ≥ 7.0 mmol/l] or fasting plasma glucose ≥7.0 and multivariable models adjusting for age at mmol/l at the 20-year reinvestigation) or the baseline, smoking status, and physical activity use of anti-diabetic medication at any (Table 3). Obese participants regardless of investigations.(14) Of the present study MetS-status had a more than ten-fold sample, 1364 participants attended the 10- increased risk for diabetes as compared to year reinvestigation and in 967 participants normal weight individuals without the MetS. attended the 20-year reinvestigation. In those Interestingly, the associations were similar who did not attend the re-investigations, the when excluding participants with impaired Swedish national hospital discharge register fasting glucose at baseline (see Table 3). was used to identify additional participants BMI/IR-categories and type 2 diabetes who developed diabetes during the 20 year incidence. The risk of diabetes during follow- follow-up (ICD-9 code 250 or ICD-10 E10- up was higher in the overweight and obesity E14). categories and with prevalent IR compared to Statistical analysis. We investigated the normal weight individuals without IR, both in associations of baseline BMI/MetS status to crude and multivariable models (Table 4). the incidence of diabetes using crude and The obese participants with IR were at highest multivariable logistic regression. These risk for diabetes at the investigation after 20 multivariable models were adjusted for age at years as compared to the normal weight baseline (continuous), smoking status individuals without IR (Table 4), however (dichotomous), and level of physical activity also the obese without IR had a more than 11- (ordinal). Also, the association between fold increased diabetes risk. Moreover, the BMI/IR categories and the incidence of associations were similar when excluding diabetes was investigated in a similar manner. participants with at In order to elucidate whether participants with baseline (see Table 4) impaired fasting glucose at baseline were driving the associations, we performed CONCLUSIONS secondary analyses where participants with Principal findings. In the present study, impaired fasting glucose at baseline were middle-aged men with MetS or IR had an excluded (fasting blood glucose >5.6-6.1 increased risk of type 2 diabetes, regardless of mmol/L, n=134). BMI status during 20 years of follow-up, P-values <0.05 from two-sided tests were compared to normal weight men without considered statistically significant. The MetS or IR. The highest risk estimate was statistical software package STATA 10.0 seen in obese participants with insulin (Stata Corporation, College Station, USA) resistance. In contrast to previous studies, also was used. the overweight and obese without MetS or without IR had a markedly increased diabetes risk. Thus, our data provides further evidence

4 BMI, metabolic syndrome and diabetes risk

that opposes the notion of overweight and or obese persons without the MetS or IR obesity without metabolic derangements as should be considered to have a substantially harmless conditions. Interestingly, the higher risk for diabetes compared to normal association between BMI/MetS- BMI/IR- weight persons without the MetS. The categories and diabetes incidence were influence of on risk in such independent of the level of physical activity. individuals needs to be determined in Comparisons with the literature. Although interventions studies with pre-defined numerous studies have reported the separate MetS/IR-subgroups and hard endpoints. Until associations between BMI, MetS, IR and the such studies are available, our data opposes risk for type 2 diabetes(1; 2; 15), we are the concept that overweight/obese without the aware of only one study that has investigated MetS should be withheld weight loss associations between BMI/MetS-, BMI/IR- interventions. categories and diabetes risk.(8) In the Strength and limitations of the study. The previous study by Meigs and co-workers, all major strength of the present study is the long participants with MetS or IR were at higher follow-up period in a well-characterized risk for diabetes regardless of BMI-status, population-based sample. The major while the overweight/obese without the MetS limitation is that the study was performed in were at no increased risk. (8) Moreover, obese middle-aged males of Northern European participants without IR were at a threefold ethnicity, limiting the generalizability to higher risk for diabetes relative to normal women and other age- and ethnic groups. weight participants without IR, while the Another limitation is that we used a modified overweight without IR were at no increased version of the NCEP criteria. Instead of waist risk..(8) There are several differences that circumference, BMI was used to define may explain the partly conflicting results central obesity. The usefulness of waist between the present and this prior study: The circumference was not evident in the early baseline of the present study was seventies and therefore only measured in a approximately twenty years earlier as small proportion of the sample. However, as compared to the study by Meigs and co- the results were similar when using BMI/IR- workers. Our study sample consisted of men categories it is not likely that the potential only with a very narrow age-span, and the misclassification of participants have had a percentage of overweight and obese major impact on our results. Moreover, our participants was substantially lower as study was also limited by the fact that there compared to the previous study. Moreover, were few participants in some of the our study had longer follow-up and a BMI/MetS- and BMI/IR-categories leading to somewhat different approach of identifying wider confidence intervals and consequently a diabetes cases and controls during follow-up higher uncertainty regarding the level of the that may explain the higher event rates in the risk estimate. Accordingly, no firm present study. conclusions should be drawn regarding a Clinical implications. Given the favourable potential dose-response relationship between metabolic profile of the MHO individuals, the the BMI/MetS-, BMI/IR-categories. Ideally, benefits of weight loss in this subgroup has our results should be validated in study been questioned(5; 14; 16) and some small populations with larger number of obese scale intervention studies have suggested that participants. Finally, for those who did not weight loss in this group may lead to a attend re-investigation we used the Swedish worsened risk profile (17; 18). However, Hospital Discharge Register to identify based on our observational data, overweight participants who developed diabetes during

5 BMI, metabolic syndrome and diabetes risk

follow-up. As not all patients with diabetes discussion, reviewed/edited manuscript. E.I. are hospitalized, it is likely that some contributed to discussion, reviewed/edited participants who developed diabetes during manuscript. L.L. researched data, contributed follow-up were incorrectly classified as non- to discussion, reviewed/edited manuscript. diabetics in our analyses. However, any such misclassification would conservatively bias ACKNOWLEDGEMENTS the risk estimates. This study was supported by The Swedish Conclusion. The increased risk for type 2 Research Council (2006-6555), Swedish diabetes in overweight/obese men without the Heart-Lung foundation, and Uppsala MetS or IR in the present study, provide University. The funding sources did not play additional evidence that opposes the existence any role in the design and conduct of the of a healthy obese phenotype as based on the study; collection, management, analysis, and definition of absence of the MetS or IR. interpretation of the data; and preparation, review, or approval of the manuscript. There Author contributions. J.Ä. researched were no conflicts of interest for any of the data, wrote the manuscript. J.S contributed to authors.

REFERENCES 1. Vazquez G, Duval S, Jacobs DR, Jr., Silventoinen K: Comparison of body mass index, waist circumference, and waist/hip ratio in predicting incident diabetes: a meta-analysis. Epidemiol Rev 29:115-128, 2007 2. Nyamdorj R, Qiao Q, Lam TH, Tuomilehto J, Ho SY, Pitkaniemi J, Nakagami T, Mohan V, Janus ED, Ferreira SR: BMI compared with central obesity indicators in relation to diabetes and hypertension in Asians. Obesity (Silver Spring) 16:1622-1635, 2008 3. Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) final report. Circulation 106:3143-3421, 2002 4. Brochu M, Tchernof A, Dionne IJ, Sites CK, Eltabbakh GH, Sims EA, Poehlman ET: What are the physical characteristics associated with a normal metabolic profile despite a high level of obesity in postmenopausal women? J Clin Endocrinol Metab 86:1020-1025, 2001 5. Karelis AD, Faraj M, Bastard JP, St-Pierre DH, Brochu M, Prud'homme D, Rabasa-Lhoret R: The metabolically healthy but obese individual presents a favorable profile. J Clin Endocrinol Metab 90:4145-4150, 2005 6. Karelis AD: Metabolically healthy but obese individuals. Lancet 372:1281-1283, 2008 7. Arnlov J, Ingelsson E, Sundstrom J, Lind L: Impact of body mass index and the metabolic syndrome on the risk of cardiovascular disease and in middle-aged men. Circulation 121:230-236, 2010 8. Meigs JB, Wilson PW, Fox CS, Vasan RS, Nathan DM, Sullivan LM, D'Agostino RB: Body mass index, metabolic syndrome, and risk of type 2 diabetes or cardiovascular disease. J Clin Endocrinol Metab 91:2906-2912, 2006 9. Karelis AD, Brochu M, Rabasa-Lhoret R: Can we identify metabolically healthy but obese individuals (MHO)? Diabetes Metab 30:569-572, 2004

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10. Stefan N, Kantartzis K, Machann J, Schick F, Thamer C, Rittig K, Balletshofer B, Machicao F, Fritsche A, Haring HU: Identification and characterization of metabolically benign obesity in humans. Arch Intern Med 168:1609-1616, 2008 11. Byberg L, Zethelius B, McKeigue PM, Lithell HO: Changes in physical activity are associated with changes in metabolic cardiovascular risk factors. Diabetologia 44:2134-2139, 2001 12. Sattar N, Gaw A, Scherbakova O, Ford I, O'Reilly DS, Haffner SM, Isles C, Macfarlane PW, Packard CJ, Cobbe SM, Shepherd J: Metabolic syndrome with and without C-reactive as a predictor of coronary heart disease and diabetes in the West of Scotland Coronary Prevention Study. Circulation 108:414-419, 2003 13. Matthews DR, Hosker JP, Rudenski AS, Naylor BA, Treacher DF, Turner RC: Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia 28:412-419, 1985 14. World Health Organization: Definition, Diagnosis and Classification of Diabetes Mellitus and its Complications: Report of a WHO Consultation. Part 1: Diagnosis and Classification of Diabetes Mellitus. Geneva, World Health Organization, 1999 15. Ford ES, Li C, Sattar N: Metabolic syndrome and incident diabetes: current state of the evidence. Diabetes Care 31:1898-1904, 2008 16. Sims EA: Are there persons who are obese, but metabolically healthy? 50:1499- 1504, 2001 17. Karelis AD, Messier V, Brochu M, Rabasa-Lhoret R: Metabolically healthy but obese women: effect of an energy-restricted . Diabetologia 51:1752-1754, 2008 18. Shin MJ, Hyun YJ, Kim OY, Kim JY, Jang Y, Lee JH: Weight loss effect on inflammation and LDL oxidation in metabolically healthy but obese (MHO) individuals: low inflammation and LDL oxidation in MHO women. Int J Obes (Lond) 30:1529-1534, 2006

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Table 1 Modified National Cholesterol Education Program Adult Treatment Pane III metabolic syndrome definition used in the present study Metabolic syndrome present if 3 or more of the following criteria is fulfilled: • Fasting blood glucose ≥5.6 mmol/l (100 mg/dl)* • Blood pressure ≥130/85 mm Hg or treatment • ≥1.7 mmol/l (150 mg/dl) • High density lipoprotein cholesterol <1.04 mmol/l (40 mg/dl) • Body mass index ≥29.4 kg/m2 * Corresponds to plasma glucose ≥ 6.1 mmol/l (110 mg/dl)(14)

Table 2. Cardiovascular risk factors in different BMI/ MetS-categories for participants with 10 year follow-up data Normal weight Normal weight Overweight Overweight Obese Obese Without MetS With MetS Without MetS With MetS Without MetS With MetS n 853 60 557 117 28 60 Age (years) 49.6 (0.6) 49.6 (0.5) 49.6 (0.6) 49.5 (0.6) 49.7 (0.4) 49.7 (0.6) Body mass index (kg/m2) 22.6 (1.6) 23.3 (1.3) 26.7 (1.3) 27.5 (1.4) 32.2 (2.2) 32.9 (2.7) Systolic blood pressure (mmHg) 129 (16) 135 (17) 134 (17) 142 (18) 139 (17) 148 (21) Diastolic blood pressure (mmHg) 80 (10) 86 (9) 84 (10) 89 (10) 90 (12) 95 (12) Fasting blood glucose (mmol/l) 4.8 (0.5) 5.1 (0.6) 4.9 (0.5) 5.2 (0.5) 4.9 (0.4) 5.2 (0.5) Fasting blood insulin (mU/l) 10.5 (5.2) 12.9 (4.8) 13.5 (6.5) 16.4 (10.0) 16.1 (4.8) 24.5 (12.5) Serum HDL-cholesterol (mmol/l) 1.5 (0.4) 1.0 (0.2) 1.4 (0.3) 1.0 (0.3) 1.4 (0.4) 1.2 (0.3) Serum triglycerides (mmol/l) 1.6 (0.7) 2.9 (3.0) 1.9 (0.8) 2.9 (1.4) 1.5 (0.4) 3.1 (2.4) HOMA index (mU/l* mmol/l) 2.3 (1.2) 3.0 (1.2) 2.9 (1.5) 3.9 (2.5) 3.5 (1.1) 5.7 (2.9) Current smoking, n (%) 463 (54) 42 (70) 253 (45) 66 (56) 9 (32) 33 (55) Hypertension, n (%) 273 (32) 24 (40) 259 (46) 79 (68) 17 (61) 46 (77) Hypertension treatment, n (%) 21 (3) 1 (2) 20 (4) 12 (10) 3 (11) 9 (15) Dyslipidemia, n (%) 366 (43) 58 (97) 331 (59) 108 (92) 12 (43) 46 (77) Lipid lowering treatment, n (%) 6 (1) 0 (0) 11 (2) 2 (2) 0 (0) 0 (0) Data are means (standard deviations). Normal weight, body mass index <25 kg/m2; overweight, body mass index 25 kg/m2-30 kg/m2; obese, body mass index >30 kg/m2; Dyslipidemia -Total cholesterol / HDL cholesterol ratio ≥5.0 or lipid lowering treatment. Abbreviations: MetS, Metabolic syndrome; LDL, low-density lipoprotein; HDL, high-density lipoprotein

8 BMI, metabolic syndrome and diabetes risk

Table 3 Diabetes incidence during 20 years follow-up in groups with different combinations of BMI and metabolic syndrome in the whole sample and in participants with normal fasting blood glucose at baseline (<5.6 mmol/l) Normal weight Normal weight Overweight Overweight Obese Obese Without MetS With MetS Without MetS With MetS Without MetS With MetS Whole sample (n=1675) No. of events/ no. at risk 32/853 7/60 67/557 27/117 9/28 18/60 Crude odds ratio (referent) 3.39 (1.43-8.04)† 3.51 (2.27-5.42)‡ 7.70 (4.41-13.43)‡ 12.15 (5.10-28.96)‡ 11.00 (5.71-21.18)‡ Multivariable odds ratio (referent) 3.28 (1.38-7.81)† 3.50 (2.26-5.42)‡ 7.77 (4.44-13.62)‡ 11.73 (4.88-28.16)‡ 10.06 (5.19-19.51)‡

Normal fasting glucose (n=1541) No. of events/ no. at risk 28/817 4/44 60/529 15/78 9/28 9/45 Crude odds ratio (referent) 2.82 (0.94-8.42) 3.60 (2.27-5.73)‡ 6.71 (3.41-13.21)‡ 13.35 (5.55-32.11)‡ 7.04 (3.10-18.03)‡ Multivariable odds ratio (referent) 2.77 (0.92-8.33) 3.64 (2.28-5.81)‡ 6.87 (3.46-13.64)‡ 13.19 (5.42-32.09)‡ 6.37 (2.77-14.64)‡ Multivariable models adjusted for age, smoking status, and level of physical activity. ‡ p<0.001, † p<0.01, * p<0.05 Definitions and abbreviations, see Table 1.

Table 4 Diabetes incidence during 20 years follow-up in groups with different combinations of BMI and insulin resistance in the whole sample and in participants with normal fasting blood glucose at baseline (<5.6 mmol/l) Normal weight Normal weight Overweight Overweight Obese Obese Without IR With IR Without IR With IR Without IR With IR Whole sample (n=1385) No. of events/ no. at risk 17/652 13/103 38/389 28/172 5/21 16/48 Crude odds ratio (referent) 5.40 (2.54-11.48)‡ 4.04 (2.25-7.27)‡ 7.26 (3.87-13.63)‡ 11.67 (3.83-35.55)‡ 18.68 (8.65-40.32)‡ Multivariable odds ratio (referent) 5.24 (2.46-11.16)‡ 4.09 (2.72-7.37)‡ 7.29 (3.87-13.72)‡ 11.22 (3.67-34.35)‡ 17.06 (7.84-37.14)‡

Normal fasting glucose (n=1269) No. of events/ no. at risk 15/622 9/87 31/360 19/143 5/19 9/38 Crude odds ratio (referent) 4.66 (1.98-11.03)‡ 3.81 (2.03-7.17)‡ 6.20 (3.07-12.54)‡ 14.46 (4.61-45.30)‡ 12.56 (5.07-31.09)‡ Multivariable odds ratio (referent) 4.55 (1.92-10.77)‡ 3.87 (2.05-7.29)‡ 6.28 (3.09-12.78)‡ 13.80 (4.38-43.41)‡ 11.70 (4.68-29.25)‡ Multivariable models adjusted for age, smoking status, and level of physical activity. ‡ p<0.001, † p<0.01, * p<0.05 IR = insulin resistance defined as the top quartile of HOMA insulin resistance >3.43, other definitions and abbreviations, see Table 1.

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