HIV/AIDS mortality attributable to alcohol use in South Africa: a comparative risk assessment by socioeconomic status

Abstract

Objectives: To quantify HIV/AIDS mortality attributable to alcohol use in the adult general population of South Africa in 2012 by socioeconomic status (SES).

Design: Comparative risk assessment based on secondary individual data, aggregate data and risk relations reported in the literature.

Setting: South African adult general population.

Participants: For metrics of alcohol use by SES, sex and age: 27 070 adults that participated in a nationally representative survey in 2012. For HRs of dying from HIV/AIDS by SES: 87 029 adults that participated in a cohort study (years 2000 to 2014) based out of the Umkhanyakude district, KwaZulu-Natal.

Main outcome measures: Alcohol-attributable fractions for HIV/AIDS mortality by SES, age and sex were calculated based on the risk of engaging in condom-unprotected sex under the influence of alcohol and interactions between SES and alcohol use. Age-standardised HIV/AIDS mortality rates attributable to alcohol by SES and sex were estimated using alcohol-attributable fractions and SES-specific and sex-specific death counts. Rate ratios were calculated comparing age-standardised rates in low versus high SES by sex.

Results: The age-standardised HIV/AIDS mortality rate attributable to alcohol was 31.0 (95% uncertainty interval (UI) 21.6 to 41.3) and 229.6 (95% UI 108.8 to 351.6) deaths per 100 000 adults for men of high and low SES, respectively. For women the respective rates were 10.8 (95% UI 5.5 to 16.1) and 75.5 (95% UI 31.2 to 144.9). The rate ratio was 7.4 (95% UI 3.4 to 13.2) for men and 7.0 (95% UI 2.8 to 18.2) for women. Sensitivity analyses corroborated marked differences in alcohol-attributable HIV/AIDS mortality, with rate ratios between 2.7 (95% UI 0.8 to 7.6; women) and 15.1 (95% UI 6.8 to 27.7; men).

Conclusions: The present study showed that alcohol use contributed considerably to the socioeconomic differences in HIV/AIDS mortality. Targeting HIV infection under the influence of alcohol is a promising strategy for interventions to reduce the HIV/AIDS burden and related socioeconomic differences in South Africa.

Keywords: AIDS; HIV; South Africa; alcohol; burden of disease; inequalities; socioeconomic status.

Figure 1

Conceptual framework linking alcohol use and socioeconomic status to HIV/AIDS mortality.

Figure 2

Schematic overview of the data sources, relative risks and core data processing steps used to quantify alcohol-attributable HIV/AIDS mortality by SES in South Africa for the year 2012. A subgroup was defined by SES, age and sex. HIV risk is referring to HIV acquired through condom-unprotected sex under the influence of alcohol. Sources: Probst et al, Probst et al, Scott-Sheldon et al, Ahmad et al, Shisana et al , Kehoe et al, Statistics South Africa. AAF, alcohol-attributable fraction; GISHA, Global Information System on Alcohol and Health; SABSSM, South African National HIV Prevalence, Incidence and Behaviour Survey; SES, socioeconomic status.

Figure 3

Prevalence of current drinking and sample size by subgroup based on the South African National HIV Prevalence, Incidence and Behaviour Survey, 2012.

Figure 4

One minus the cumulative density of the gamma distribution of alcohol use for high (dashed) and low SES (dotted) and by age and sex in the adult (15+) South African general population in 2012. The graph indicates the proportion of current drinkers (y-axis) with an average level of drinking of alcohol use equal to or above the grams of pure alcohol per day indicated on the x-axis.