European Journal of Cardiovascular Medicine

Obesity is a global health concern with the World Health Organization, estimating 500 million adults to be obese (body mass index (BMI >30) in 2008.¹ Obesity is an excess of body fat that is detrimental to health and is often assessed clinically by the body mass index (BMI).² According to the World Health Organization definition, a person is considered overweight if her/his body mass index (BMI) is >25, and obese if BMI is ⩾30.³ Obesity is a complex inflammatory chronic condition that affects both children and adults and has become a worldwide epidemic. Diets enriched in fat and calories and a sedentary lifestyle with limited physical activity are usually blamed for the increase in the prevalence of obesity. The most visible sign of obesity is accumulation of body fat.⁴, usually measured by body mass index (BMI) ≥ 30 kg/m5 as stated by the Centers for Disease Control and Prevention (CDC). BMI however only measures total body weight without taking into account changes in body fat ⁵ as well as the location of the fat, visceral versus subcutaneous, which is important as the accumulation of fat between different depots is more important than the amount of total fat in the body for the risk of developing obesity-associated conditions. The subcutaneous adipose tissue (AT) is generally located in lower parts of the body, and is measured by hip, thigh and leg circumference, but can also accumulate in the area around the neck. The visceral AT surrounds internal organs and includes omental, mesenteric, epididymal, perirenal, retroperitoneal, epicardial.⁶ Several studies have also shown body mass index (BMI) to be associated with increased risk of infections,^7,8 Mechanisms that predispose obese patients to infections include decreased cell-mediated immune responses, immune system dysregulation, respiratory dysfunction, underlying comorbidities, and altered pharmacokinetic and pharmacodynamics parameters.^9-10 A study of American women found that skin barrier and moisturizing functions were significantly impaired by obesity, resulting in considerable dryness and roughness, compared with nonobese women.¹¹ The present study was conducted to assess the effects of obesity on infections with focus on skin infections

In the present study, 500 participants who were completing a questionnaire on anthropometric measures were included. Participants younger than 18 years, subjects with missing data on height or weight, or underweight (BMI <18.5 kg/m2) were excluded from the study. Height and weight were self-reported in the questionnaire and BMI was calculated as weight in kilograms divided by height in meters squared. BMI was categorized according to the WHO standard classification into normal weight (≥18.5 to <25 kg/m2; reference), overweight (≥25 to <30 kg/m2) and obesity (≥30 kg/m2).12380 participants with BMI ≥25kg/m2 were included in the study. Community acquired infections were defined according to the International Classification of Diseases (ICD), Tenth Revision (ICD-10). To avoid nosocomial infections, only the primary inpatient or outpatient diagnosis code was used. Infections were grouped as upper respiratory tract infections, lower respiratory tract infections, gastrointestinal tract infections, skin and subcutaneous tissue infections, urinary tract infections, gynaecological infections, sepsis, and other infections. Data was analyzed using SPSS version 21. p value ≤0.01 considered statistically significant.

In the present study, 41.05% participants were males and 58.94% were females. mean age was 49.8 years. The most common site for infections was the upper respiratory tract among females 23.21%) and the lower respiratory tract among males (21.79%). Skin And Subcutaneous Tissue Infections occur in 12.8% males and 10.71% females.

Table 1: Demographic data of patients with BMI ≥25kg/m2

Table 2: Total number of infections stratified by gender, infection type

Epidemiological data has begun to emerge that indicates obesity is a risk factor for infectious diseases.¹³ First, adipose tissue secretes adipokines, including leptin and adiponectin, that modulate the immune response. Second, an altered respiratory physiology, skin folds and diminished peripheral blood perfusion are factors linked to obesity which might induce an increased risk for respiratory tract infections, skin infections and abscesses, respectively.¹⁴ Lastly, the differences observed between males and females might be due to diverse anatomical constructions.¹⁴ In the present study, 41.05% participants were males and 58.94% were females. mean age was 49.8 years. The most common site for infections was the upper respiratory tract among females (23.21%) and the lower respiratory tract among males (21.79%). Skin And Subcutaneous Tissue Infections occur in 12.8% males and 10.71% females. Data on the association between obesity and the outcome of skin infections are limited. A prospective cohort study has indicated the outcome of cellulitis to be worse in the morbidly obese as compared with non-obese subjects.¹⁵ Obesity increases risk of gastrointestinal complications such as non-alcoholic fatty liver disease (NAFLD). Several authors have demonstrated that obesity is a risk factor for the development of steatosis in patients with chronic hepatitis C infection, as BMI correlates with the grade of steatosis.¹⁶ Moreover, obese subjects are more prone to develop various skin infections such as intertrigo, candidiasis, furunculosis, erythrasma, tinea cruris, and folliculitis and to show rapidly progressive bacterial bone and joint infections. Campitelli MA, et al observed higher rates of outpatient visits for Acue Respiratory Infections during influenza season periods compared with normal weight individuals for those who were overweight (BMI 25–29.9; rate ratio (RR) 1.10; 95% confidence interval (95% CI) 1.07–1.13), obese class I (BMI 30–34.9; RR 1.17; 95% CI 1.13–1.22) and obese class II or III (BMI X35; RR 1.19; 95% CI 1.12–1.25). Associations of a similar magnitude were observed during non-influenza season periods.¹⁷

The present study concluded that obesity was associated with increased risk of infections in both genders. Skin and subcutaneous tissue infections occur in 12.8% males and 10.71% females. Obesity significantly increases both the risk and adverse outcomes of skin infections. Immune dysfunction, impaired skin barrier integrity, poor circulation, and associated comorbidities contribute to increased susceptibility, severity, delayed healing, and recurrence of infections.

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