Obesity, metabolic health, and history of Cytomegalovirus infection in the general population

Context:Commoncommunity-acquired infections, such as cytomegalovirus (CMV),maycontribute to the development of obesity and metabolic dysfunction, but empirical evidence is scarce. Objective: We examined the associations between CMV, obesity and metabolic characteristics in a large, general population-based sample of adults. Design and setting: An observational study in community dwelling adults from the general population, ‘Understanding Society – the UK Household Longitudinal Study’. Participants: 9,517 men and women (aged 52.4 ± 16.4 yrs; 55.3% female). Measures: CMV infection was measured using Immunoglobulin G (IgG) from serum. Obesity was defined as body mass index ≥30 kg/m2. Based on blood pressure, HDL-cholesterol, triglycerides,glycated haemoglobin A1c, and C-reactive protein, participants were classified as ‘healthy’ (0 or 1 metabolic abnormality) or ‘unhealthy’ (≥2 metabolic abnormalities). Results: A positive CMV test was recorded in 47.5% of the sample. There was no association between CMV and obesity. Of the individual metabolic risk factors, CMV was positively associated with glycated haemoglobin and HDL-cholesterol. In combination, only ‘unhealthy non-obese’ participants had modestly increased odds of CMV (odds ratio compared to healthy normal weight = 1.12, 95% confidence interval 1.00 – 1.26) after adjusting for a range of variables. CMV was associated with an increased prevalence of cardiovascular diseases (odds ratio=1.67; 1.07 – 2.60) independently of obesity, metabolic risk factors, and other covariates. Conclusion: Our findings suggest a weak but statistically significant association between CMV and metabolic dysfunction in non-obese adults. This relationship appears to be masked in the obese, possibly by the effects of excess adiposity on metabolism.