Southern Africa Labour and Development Research Unit (SALDRU), School of Economics, University of Cape Town, Middle Campus, Cape Town, South Africa Department of Medical Ethics and Health Policy, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA Centre for the AIDS Programme of Research in South Africa (CAPRISA) Health Economics and HIV and AIDS Research Division (HEARD), University of KwaZulu-Natal, Durban Epicentre AIDS Risk Management (Pty) Limited, Sandton, South Africa.
AIDS. 2020 Jan 1;34(1):149-154. doi: 10.1097/QAD.0000000000002362.
Cross-sectional and cohort studies draw different conclusions on whether age-disparate partnerships increase HIV-acquisition risk for young women. We investigated whether age-disparities were associated with HIV-infection risk early in relationships. This could result in the exclusion of women who seroconverted during high-risk age-disparate partnerships from cohort studies of HIV incidence - which exclude HIV-positive women - and explain null findings in these studies.
Prospective cohort study.
We used data on 15-24-year-old, HIV-negative women in heterosexual partnerships (N = 830) in KwaZulu-Natal, South Africa. The association between age-disparate partnering (i.e., male partner ≥5 years older) and subsequent HIV seroconversion was assessed using Cox hazard models. We examined heterogeneity in HIV-acquisition risk by duration of partnership (defined by quartiles) at cohort enrolment.
During 1139 person-years (mean: 1.4 years) of follow-up, 54 (6.5%) women seroconverted, a weighted HIV-incidence estimate of 4.41/100 person-years [95% confidence interval (CI): 3.30-6.06]. HIV-acquisition risk did not differ significantly between women in age-disparate vs. age-similar partnerships (adjusted hazard ratios: 1.10, 95% CI: 0.55-2.21). However, for women in the shortest partnership quartile (<1.09 years) at baseline, risk of HIV seroconversion was higher for women in age-disparate partnerships (adjusted hazard ratios: 3.13, 95% CI: 1.02-9.65, P = 0.047). HIV acquisition was not statistically different by partnership type among women in longer partnerships.
The association between age-disparate partnerships and HIV-acquisition risk is evident early in young women's relationships. Results provide a potential explanation for null findings in cohort studies, whose research designs may exclude women in such partnerships, and affirms the elevated risk of HIV acquisition for young women in age-disparate relationships.
横断面研究和队列研究得出的结论不同，即年龄差异较大的伴侣关系是否会增加年轻女性感染艾滋病毒的风险。我们调查了年龄差异是否与早期伴侣关系中的艾滋病毒感染风险相关。这可能导致从队列研究中排除在高风险年龄差异伴侣关系中发生血清转换的女性，而这些研究排除了艾滋病毒阳性女性，从而解释了这些研究中的无效发现。
前瞻性队列研究。
我们使用了南非夸祖鲁-纳塔尔省 15-24 岁、异性恋伴侣中的艾滋病毒阴性女性（N=830）的数据。使用 Cox 风险模型评估年龄差异较大的伴侣关系（即男性伴侣年龄大 5 岁以上）与随后艾滋病毒血清转换之间的关联。我们在队列登记时通过（分为四等分的）伴侣关系持续时间来检查艾滋病毒获得风险的异质性。
在 1139 人年（平均：1.4 年）的随访期间，54 名（6.5%）女性发生了血清转换，加权艾滋病毒发病率估计值为 4.41/100 人年[95%置信区间（CI）：3.30-6.06]。在年龄差异较大和年龄相似的伴侣关系中，艾滋病毒获得风险没有显著差异（调整后的风险比：1.10，95%CI：0.55-2.21）。然而，在基线时处于最短伴侣关系四分位（<1.09 年）的女性中，年龄差异较大的伴侣关系中的女性发生艾滋病毒血清转换的风险更高（调整后的风险比：3.13，95%CI：1.02-9.65，P=0.047）。在较长伴侣关系中的女性中，按伴侣关系类型统计，艾滋病毒获得情况无统计学差异。
年龄差异较大的伴侣关系与艾滋病毒获得风险之间的关联在年轻女性的关系早期就很明显。研究结果为队列研究中的无效发现提供了一个潜在的解释，因为这些研究设计可能排除了处于这种伴侣关系中的女性，并肯定了年轻女性在年龄差异较大的关系中获得艾滋病毒的风险较高。
