MedialResearch.com Interview with:
Dr Catherine M. Phillips
Health Research Board Centre for Diet and Health Research
Room 4.033, Department of Epidemiology and Public Health
Western Gateway Building, University College Cork, Cork, Ireland
MedialResearch.com: What are the main findings of the study?
Answer: Obesity is associated with increased risk of diabetes and heart disease leading to reduced life expectancy. However in recent years it has been recognized that not all obese individuals are at increased risk – these individuals have been described as being metabolically healthy obese (MHO) in that despite carrying excess weight they do not have the typical abnormal metabolic features associated with obesity such as hypertension, insulin resistance and alterations to their lipid profile.
It is not clear what factors determine whether an obese person becomes metabolically healthy or unhealthy. In this study conducted at the Dept. of Epidemiology and Public Health at University College Cork, Ireland, we examined levels of a range of inflammatory markers in 2047 middle-aged Irish adults to investigate to what extent differences between metabolically healthy and unhealthy obese and non-obese male and female adults are explained by inflammatory status. Participants, who were between the ages of 50 and 69, completed lifestyle questionnaires, physical and clinical assessments, and underwent blood testing so their body mass index (BMI), metabolic profiles and inflammatory markers could be determined. We found that, regardless of a person’s BMI, having a favorable inflammatory profile was associated with being metabolically healthy. Specifically metabolically healthy individuals presented with lower levels of complement component 3, C reactive protein, tumour necrosis factor alpha, interleukin 6, plasminogen activator inhibitor-1, reduced white blood cell count and higher adiponectin levels compared to their metabolically unhealthy counterparts.
MedialResearch.com: Were any of the findings unexpected?
Answer: Whether inflammation accounts for the metabolic differences observed between metabolically healthy and unhealthy individuals is relatively unknown. Conflicting findings regards inflammatory status and MHO have been previously reported – which may be due to a number of reasons including differences in ethnicity and age-group, small subject numbers and investigation of a limited number of limited inflammatory markers, together with different metabolic health criteria being used to define MHO. Our study involves characterisation of the largest range of inflammatory markers among metabolic health obese and non-obese phenotypes conducted to date. Furthermore we examined inflammatory status across a range of metabolic health definitions, as no standard metabolic health definition exists.
MedialResearch.com: What should clinicians and patients take away from your report?
Answer: The findings of our research may be of public health importance and clinical significance in terms of both screening and stratification based on an individual’s metabolic health phenotype. From a public health standpoint, we need better methods for identifying which obese people face the greatest risk of diabetes and heart disease. A better understanding of obese subgroups may be useful in the identification of individuals who are most unhealthy and thus at greatest cardiometabolic risk for whom appropriate therapeutic or intervention strategies should be prioritized and/or developed.
MedialResearch.com: What recommendations do you have for future research as a result of this study?
Answer: Inflammatory markers may offer a potential strategy for identifying people who could benefit most from interventions and requires further investigation. Furthermore the potential of medical, lifestyle or dietary interventions to attenuate the transition from metabolically healthy to unhealthy obesity, or indeed reversion from an unhealthy to a healthy metabolic state remains an intriguing possibility, which would be worthwhile to address in future research.
Does Inflammation Determine Metabolic Health Status in Obese and Nonobese Adults?
Catherine M. Phillips and Ivan J. Perry
Does Inflammation Determine Metabolic Health Status in Obese and Nonobese Adults? JCEM jc.2013-2038; doi:10.1210/jc.2013-2038