Newly diagnosed cases of HIV in those aged 50 years and older and those less than 50: 2008-2017

Abstract

Background: Canada's population is aging, with nearly forty percent of Canadians aged 50 years or more. As the population ages, unique challenges related to health are becoming evident, including increasing rates of sexually transmitted and bloodborne infections. Understanding the epidemiology of HIV in older adults is important to guide prevention and control programs.

Objective: To assess trends in newly diagnosed cases of HIV in Canada among those aged 50 years and older (≥50 years) and those aged less than 50 (<50 years), and to compare their basic demographic characteristics and exposure categories for the period of 2008 to 2017.

Methods: National surveillance of HIV is conducted by the Public Health Agency of Canada through voluntary submission of data by provincial/territorial public health authorities. Descriptive analyses were conducted on reported cases of HIV between January 1, 2008, to December 31, 2017 to compare the demographic profiles and exposure category for the two age groups.

Results: Between 2008 and 2017, the proportion of newly diagnosed HIV cases among those ≥50 years increased from 15.1% to 22.8%. The HIV diagnosis rates for both older males and older females increased over time, with a relatively higher increase for females. A higher proportion of newly diagnosed HIV cases were male in the older group (81.2%) compared to the younger group (74.6%). Among both older and younger males, the most common exposure category for HIV was being gay, bisexual and other men who have sex with men (gbMSM), followed by heterosexual contact and injection drug use; however, the relative proportions varied by age with the gbMSM category being higher in the <50 group.

Conclusion: In Canada, over 20% of all newly diagnosed cases of HIV are now in people 50 years of age and older. HIV testing and prevention initiatives, historically aimed at younger populations, may not have the same impact for older populations. These data can be used to inform future public health actions designed to address HIV in older populations.

Keywords: 50 years of age and older; HIV; bisexual; gay; men who have sex with men; people who inject drugs; surveillance.

Figure 1

Reported numbers and rates (per 100,000 population) of HIV diagnoses in older (≥50 years), younger (<50 years) and all Canadians where age was reported, 2008–2017^a Population data source: Annual Demographic Statistics, Statistics Canada (13) ^a Excludes cases with unknown age at HIV diagnosis

Figure 2

Annual rates (per 100,000 population) of new HIV diagnoses by age category and sex, Canada, 2008–2017^a,b Abbreviations: ≥50, age 50 years and older; <50, younger than 50 years of age ^a Population data source: Annual Demographic Statistics, Statistics Canada (13) ^b Excludes cases where age at HIV diagnosis is unknown. Excludes cases where sex is transgender, transsexual, other, unknown or not reported