Low N, Pfluger D, Egger M
Academic Department of Genitourinary Medicine, King's College School of Medicine & Dentistry, London, UK.
AIDS. 1997 Jul 15;11(9):1165-71. doi: 10.1097/00002030-199709000-00013.
Disseminated disease due to Mycobacterium avium complex (MAC) bacteria is thought to occur less frequently in Europe than in the USA. This study investigated time trends in the occurrence of, and survival with, disseminated MAC disease in the Swiss HIV Cohort Study (SHCS).
DESIGN, SETTING AND PARTICIPANTS: The SHCS participants who were free of disseminated MAC disease at registration were stratified by calendar period (1987-1989, 1990-1992, 1993-1995) in which the first recorded CD4 count was 0-49, 50-99, or 100-199 x 10(6)/l. Kaplan-Meier estimates of the probability of developing and surviving disseminated MAC disease were calculated for these nine independent groups. Multivariate analyses were performed using Cox proportional hazards regression.
The analysis was based on 6052 participants enrolled between January 1987 and December 1995 and 202 incident episodes of disseminated MAC disease recorded during a mean follow-up time of 3.5 years. The cumulative probability of MAC disease at 2 years in individuals with CD4 counts of 0-49 x 10(6)/l in 1987-1989 was 9.8% [95% confidence interval (CI) 4.4-15.2%], increasing to 29.8% (95% CI, 20.8-38.8%) in 1993-1995. Amongst those with CD4 counts from 50-99 x 10(6)/l these probabilities were 11.9% (95% CI, 5.9-17.8%), and 21.6% (95% CI, 13.9-29.2%), respectively. After adjusting for CD4 count the relative hazard of developing disseminated MAC disease in 1993-1995, compared with 1987-1989, was 1.37 (95% CI, 0.92-2.04). Median survival following diagnosis was 7.9 months with no improvement over time.
The incidence of disseminated MAC disease among SHCS participants has increased over time. More profound levels of immunosuppression amongst recent study entrants were found to explain this. When compared with US cohorts studied over the same calendar period the incidence of disseminated MAC disease in the SHCS appears to be lower. These findings are consistent with a secular effect of a more mature HIV epidemic in the US but direct comparison between the SHCS and a similar prospective cohort in the US should be undertaken to clarify this issue.
鸟分枝杆菌复合体（MAC）细菌所致播散性疾病在欧洲的发生率被认为低于美国。本研究在瑞士HIV队列研究（SHCS）中调查了播散性MAC疾病的发生时间趋势及生存情况。
设计、背景与参与者：登记时无播散性MAC疾病的SHCS参与者按首次记录的CD4细胞计数所在日历期（1987 - 1989年、1990 - 1992年、1993 - 1995年）分层，CD4细胞计数分别为0 - 49、50 - 99或100 - 199×10⁶/l。计算这九个独立组发生播散性MAC疾病及生存的概率的Kaplan - Meier估计值。使用Cox比例风险回归进行多变量分析。
分析基于1987年1月至1995年12月入组的6052名参与者，在平均3.5年的随访期间记录了202例播散性MAC疾病事件。1987 - 1989年CD4细胞计数为0 - 49×10⁶/l的个体在2年时发生MAC疾病的累积概率为9.8%[95%置信区间（CI）4.4 - 15.2%]，在1993 - 1995年增至29.8%（95%CI，20.8 - 38.8%）。CD4细胞计数为50 - 99×10⁶/l的个体中，这些概率分别为11.9%（95%CI，5.9 - 17.8%）和21.6%（95%CI，13.9 - 29.2%）。在对CD4细胞计数进行调整后，1993 - 1995年发生播散性MAC疾病的相对风险与1987 - 1989年相比为1.37（95%CI, 0.92 - 2.04）。诊断后的中位生存期为7.9个月，且未随时间改善。
SHCS参与者中播散性MAC疾病的发生率随时间增加。发现近期入组者中更严重的免疫抑制水平可解释这一现象。与同一日历期在美国进行研究的队列相比，SHCS中播散性MAC疾病的发生率似乎更低。这些发现与美国更成熟的HIV疫情的长期影响一致，但应将SHCS与美国类似的前瞻性队列进行直接比较以阐明此问题。
