Future risk of diabetes among Indians with metabolic and phenotypic obesity: Results from the 10-year follow-up of the Chennai Urban Rural Epidemiology Study (CURES-158)

AIM

To investigate the risk of type 2 diabetes (T2DM) among the combinations of BMI categories and metabolic syndrome in Asian Indians.

MATERIALS AND METHODS

Individuals from the Chennai Urban Rural Epidemiology Study cohort (n = 1,368), free of diabetes at baseline were stratified by BMI and metabolic health as metabolically healthy non-obese (MHNO), metabolically healthy obese (MHO), metabolically obese non-obese (MONO) and metabolically obese obese (MOO). Phenotypic obesity was defined as BMI ≥ 25 kg/m² and metabolic obesity as presence of any two of the metabolic abnormalities: hyperglycemia, high blood pressure, high triglyceridemia or low HDL cholesterol. Hazard ratios for progression to diabetes were estimated using Cox proportional hazard regression.

RESULTS

During median 9.1 years of follow-up, incident cases of diabetes were highest among MOO-45.1%, followed by MONO-41.3%, MHO-27.1% and MHNO-15.9%. Incidence rates of diabetes among MOO, MONO, MHO and MHNO were 57.8, 50.9, 30.4 and 18.1 per 1000 person years, respectively. Hazard ratio for diabetes development were 1.71 in MHO, 2.87 in MONO, and 3.39 in MOO compared with MHNO.

CONCLUSIONS

Increased BMI and metabolic risk factor clustering independently contribute to the increased risk of T2DM in obese individuals. Screening for metabolic abnormalities should be performed routinely in clinic to identify high-risk individuals and institute appropriate preventive measures.

High-fat feeding primes the mouse knee joint to develop osteoarthritis and pathologic infrapatellar fat pad changes after surgically induced injury

OBJECTIVE

Obesity is one of the greatest risk factors for osteoarthritis (OA) and evidence is accumulating that inflammatory mediators and innate immunity play an important role. The infrapatellar fat pad (IPFP) could be a potential local source of inflammatory mediators in the knee. Here, we combine surgical joint damage with high-fat feeding in mice to investigate inflammatory responses in the IPFP during OA development.

DESIGN

Mice (n = 30) received either a low-fat diet (LFD), high-fat diet (HFD) for 18 weeks or switched diets (LFD > HFD) after 10 weeks. OA was induced by surgical destabilization of the medial meniscus (DMM), contralateral knees served as sham controls. An additional HFD-only group (n = 15) received no DMM.

RESULTS

The most pronounced inflammation, characterized by macrophage crown-like structures (CLS), was found in HFD + DMM mice, CLS increased compared to HFD only (mean difference = 7.26, 95%CI [1.52-13.0]) and LFD + DMM (mean difference = 6.35, 95%CI [0.53-12.18). The M1 macrophage marker iNOS increased by DMM (ratio = 2.48, 95%CI [1.37-4.50]), while no change in M2 macrophage marker CD206 was observed. Fibrosis was minimal by HFD alone, but in combination with DMM it increased with 23.45% (95%CI [13.67-33.24]).

CONCLUSIONS

These findings indicate that a high-fat diet alone does not trigger inflammation or fibrosis in the infrapatellar fat pad, but in combination with an extra damage trigger, like DMM, induces inflammation and fibrosis in the infrapatellar fat pad. These data suggest that HFD provides a priming effect on the infrapatellar fat pad and that combined actions bring the joint in a metabolic state of progressive OA.

Frequency of insulin resistance in nondiabetic adult Bangladeshi individuals of different obesity phenotypes

Insulin resistance (IR) is the corner stone of metabolic obesity. This cross-sectional analytical study was aimed to find out the frequency of IR in non-diabetic adult individuals of different obesity phenotypes that would help to implement preventive measures to avoid the cardiometabolic catastrophes.

METHODS

Total 955 nondiabetic adult individuals were selected and categorized into six metabolic phenotypes by metabolic syndrome criteria in each BMI group (18.5-24.9-normal weight, 25-29.9-overweight, ≥30-obese). From them, metabolically obese normal weight, metabolically obese overweight, metabolically healthy obese and metabolically unhealthy obese were selected as Obesity phenotypes (N = 616).

RESULTS

The frequency of IR was found to be very high (60.2%) in total nondiabetic adult obese individuals (N = 616). Highest frequency of IR was found in MUO phenotype (76.3%), lowest frequency of IR was found in MONW phenotype (37.1%) and frequency of IR in MOOW and MHO phenotypes found to be identical but significantly (p < 0.0001) less than MUO and significantly (p < 0.0001) more than MONW phenotype. Among the obesity phenotypes, females were more insulin resistant than males (67.5% vs 48.1% respectively, p < 0.05). Frequency of IR found significantly (p < 0.05) more in female than male in all obesity phenotypes except in MUO phenotype where males found to show significantly (p < 0.05) higher frequency than females. Frequency of IR was significantly higher in younger (20-39 yrs) age group than 40-60 yrs age group (63.2% vs 53.5% respectively, p < 0.05).

CONCLUSION

IR is alarmingly high (60.2%) in nondiabetic adult obese individuals. Among different obesity phenotypes, it is highest (76.3%) in MUO and lowest (37.1%) in MONW.

Leptin as a cardiovascular risk marker in metabolically healthy obese: Hyperleptinemia in metabolically healthy obese

Adipokines contribute to the inflammatory process which can lead to obesity-associated cardiometabolic complications. Metabolically healthy obese individuals seem to be protected or more resistant to develop these complications and it is intriguing why some individuals develop comorbidities and others do not. Thus, we questioned whether the differences between metabolically healthy and unhealthy obese relied on the alterations in metabolic profile, characterized by serum leptin and adiponectin. A total of 142 obese adults were divided into 2 groups - metabolically healthy obese (MHO) or unhealthy obese (MUO) - and they were evaluated for anthropometric measures, body composition, blood pressure, dietary intakes and plasma levels of leptin and adiponectin. Leptin/adiponectin ratio (L/A) was calculated. Age, BMI and blood pressure were higher in the MUO. No differences in anthropometric measurements, body composition, dietary intake and dietary quality were observed between groups. Leptin were significantly higher in the MUO (53.07 ± 34.56 versus 36.27 ± 24.02 ng/ml in the MHO, r < 0.04). The logistic regression analysis demonstrated that leptin was an important factor associated with not being healthy, independent of age, body weight and BMI. There were no differences between groups for adiponectin and L/A. Leptin correlated positively with body weight (r = 0.25, r < 0.05), BMI (r = 0.38, r < 0.05) and BF (r = 0.74, r < 0.05), and negatively with FFM (r = -0.74, r < 0.05). Our findings suggest that leptin is an important cardiovascular disease marker to obese population and can contribute to evaluate metabolic risks in these individuals.