Overweight and Obesity Status in A Canadian HIV Outpatient Population
Jenn Messina RD, Alena Barron RD, Jane McCall MSN, RN St. Paul’s Hospital, Vancouver, BC, Canada
Background
Sample
Results
Worldwide rates of obesity have more than doubled since 1980. Due to the beneficial effects of highly active antiretroviral therapy (HAART), HIV infected people are living longer, experiencing lower rates of acquired immunodeficiency syndrome (AIDS) related wasting syndrome, and becoming more overweight and obese at a rate similar to the general U.S. population. Consequently, they are experiencing medical comorbidities related to excess weight. Overweight and obesity are important risk factors for the development of metabolic syndrome.
Inclusion criteria will be all patients admitted to the IDC over the past year with recorded height (ever) and weight (within the past year).
Figure 1: Statistically significant characteristics across BMI groups
Purpose of the Study The purpose of this study is to determine the prevalence of overweight and obesity in an urban outpatient HIV positive population in Vancouver, B.C. which will be compared with provincial and national rates in Canada. In addition we will determine factors that are associated with each condition. Demographic and clinical characteristics of interest include: gender, ethnicity, age, CD4+ T-cell count (at time of BMI assessment and NADIR), viral load (at time of BMI assessment), history of AIDS defining illness, ART history (years on ART, current ART, PI vs. NNRTI), hepatitis C status and injection drug use, including types of drugs used.
Research Questions Two research questions will be used to frame the study: What is the prevalence of overweight (BMI 25.00-29.99 kg/m²) status or obesity (BMI ≥ 30 kg/m²) in an outpatient HIV population? What demographic and clinical factors are associated with overweight and obesity? .
Research Design This is a cross-sectional, descriptive, retrospective study utilizing an established data base that is maintained by the Immunodeficiency Clinic at St. Paul’s hospital. All patients at the clinic are included in the database, which collects a variety of demographic details.
African/Black ethnicity
Data Analysis History of injection drug use
The primary outcome is BMI, which was categorized into 4 groups using the World Health Organization Classifications for BMI in kg/m2: (WHO, 2012) 1)
<18.5 Underweight
2)
18.50-24.99 Normal
3)
25.00-29.99 Overweight
4)
BMI > 30 Obese
The objective was to determine the prevalence of each BMI group and what factors were associated with being overweight or obese. The comparison will be obese vs. overweight vs. normal BMI. In bivariate analysis, differences across groups were assessed using Chi-Square test (or Fisher’s Exact test) for categorical variables and Wilcoxon rank-sum test for continuous variables.
Demographics The cohort consisted of 886 patients, of which 28 were underweight. Of the remaining 858, 448 (52%) were normal weight, 294 (34%) were overweight and 116 (14%) were obese. The median age was 47, the majority (90%) male, 61% Caucasian and 39% ethnic minority with 13% reporting Aboriginal ancestry and 7% African/Black ethnicity. In terms of substance use, 35% had a history of injection drug use, 15% were current marijuana users and 15% currently using illicit drugs. 32% were Hepatitis C co-infected, 89% were on ARVs with 63% on PIs and 24% had a history of AIDS defining illness (ADI). Figure 1 illustrates statistically significant difference across BMI groups (p<0.05). There were no differences with regard to: age, gender, illicit drug use, ADI, ARVs, year ARV started or time on ARV.
Current marijuana user Obese Overweight Normal
Hepatitis C positive VL<50 CD4>350 0
10
20
30
40
50 (%)
60
70
80
90
†p-value<0.001; ‡p-value=0.016
Conclusion The results of this study indicate that overweight and obesity are important issues for our Canadian, urban, outpatient HIV population showing similar trends to the general Canadian population as well as trends in the US. There is a potential for significant adverse medical co-morbidities related to excess weight for these individuals. Clinicians should be aware of these trends and consider instituting weight management programs and multidisciplinary metabolic clinics as a part of routine HIV care.
Acknowledgements / Contact Jiak Chin Koh RD, MSc, St. Paul’s Hospital Keith Chan MSc, BC Centre for Excellence in HIV/AIDS Contact: jmessina@providencehealth.bc.ca