Age-period cohort analysis of AIDS incidence rates in Rio de Janeiro, Brazil, 1985–2009

Abstract

IntroductionThe long average incubation time from HIV infection to AIDS makes it difficult to estimate the recent tendencies of HIV from AIDS incidence data. The objective of this study was to investigate the effects of three temporal components in AIDS incidence in the state of Rio de Janeiro, Brazil - age, period, and cohort.MethodsAge-specific AIDS incidence rates per 100,000 from Rio de Janeiro (Brazil) were calculated for both sexes using five-year age classes from 1985 to 2009 based on reported data from the Notifiable Disease Information System of the Brazilian Ministry of Health and from census population counts. Multivariate negative binomial models were used to analyze the risk of AIDS by age, period, and birth cohort.ResultsFrom 1985 to 2009, AIDS incidence initially increased with age in each birth cohort and then decreased (except for individuals born from 1971–1979 to 1986–1994). High peaks in the rates in each birth cohort were detected in 1995–1999 for males and in 2000–2004 for females. Multivariate analysis showed the maximum risk of AIDS in the 30–34 age group and 1958–1962 birth cohort.ConclusionAge, birth cohort, and period effects all may have influenced the AIDS incidence rates over the period investigated. From 1985 to 1999, comparison of the tendencies (by age) of the period with the birth cohort revealed opposing tendencies in individuals older than 29 years and in the youngest age groups (0 to 14 years). From 2000 to 2009, a strong age effect can be observed in both sexes. Consistent changes in period tendency curves suggest the occurrence of period effects. A reduction in the intensity of the risk of AIDS can be observed after 2000–2004.

Long-term trends of HIV/AIDS incidence in India: an application of joinpoint and age–period–cohort analyses: a gendered perspective

“…Furthermore, the results from age-specific joinpoint regression analysis indicated that in the last three decades, women were bearing a significantly higher burden of HIV incidence than men. These findings are in line with the instances from South India and South Africa where a declining incidence of HIV infection was observed; however, the incidence is higher among males than females ( 28 , 33 , 34 ). Yet, it should be noted that a persistent HIV/AIDS epidemic may prompt risk reduction behavior in survivors after the passing of close family members in the family, neighborhood, or community ( 32 ).…”

“…The highest incidence of HIV infection was observed among the 1955–1959 birth cohort among males and the 1960–1964 birth cohort among females. Decreasing rates of incidence of the disease have been observed in people born between 1950 and 1964 in Spain and Brazil ( 33 , 49 ). The decline in the incidence rates at younger ages is indicative of the effectiveness of prevention options as a national response ( 32 ).…”

Trends in AIDS Incidence in Individuals Aged 50 Years or Older in the City of Rio de Janeiro, Brazil, 1982–2011: An Age-Period-Cohort Analysis

“…Rodrigues (2013) detected similar trends in older people in Rio de Janeiro City, Brazil from 1985–1995 [24]. A study performed on injection drug users aged 15–65 years in Spain detected increasing trends in disease rates in men born between 1950 and 1962 and in women born between 1950 and 1964.…”

“…Among these limitations, we highlight the changes in the case definition of AIDS through time [12], the deficiency in the coverage of the epidemiologic surveillance system [24], slow data processing, underreporting, the high number of deaths without defined cause and inadequate death certificate completion. In addition to the cases that were not reported, data in this study excluded asymptomatic infected individuals because these data are not yet available in Brazil.…”

Spatial dynamics of AIDS incidence in the elderly in Rio de Janeiro, Brazil, 1997-2011

“…Brazilian studies have shown that men have shown 2-3 times greater risk of AIDS occurrence than women 30,31 and the peak of AIDS incidence was around 2002 in Rio de Janeiro State 31 . Apratto Junior et al 30 , detected in elderly people of Niterói a peak of AIDS incidence around 2004.…”