AIDS trend in the group of 50-year-old people and more in the previous and subsequent period to the introduction of medicines for erectile dysfunction: Brazil, 1990 to 2003

Abstract Objective Describe the behavior of the incidence of Aids in the group of 50-year-old people and more, in Brazil and its macro-regions, from 1990 to 2003, analyzing the previous and subsequent moment of introduction of medicines for erectile dysfunction in the country, in 1998. Methods An ecological study was carried out, along with a space-time analysis of the notified cases of Aids in this group of people. Models of linear regression, adjusted to the time series of Aids cases whose diagnoses date from 1990 to 1997, provided the taxes of annual average variation, as well as the expected values, so making it possible to compare incidence taxes observed and estimated from 1998 to 2003. Results 25,223 cases of Aids in the group of 50-year-old people and more had been analyzed, being the majority (84%) in the Southeast and South regions. Those regions also presented the greatest taxes of annual average variation to the year of 1997 (1.002 and 0.906, respectively), followed by the Middle-West (0.570), North (0.441) and Northeast (0.254); Brazil showed a tax of 0.588. After 1998, the comparison of the taxes accumulated from 1998 to 2003 revealed the expected higher trends than the ones observed in all regions, except for the Northeast. Conclusion The trend of growth of Aids in the 50-year-old people and more group presented greater taxes of growth from 1990 to 1997, and this growth remained in the period subsequent to the introduction of medicines for erectile dysfunction, but more slowly.

**研究目的** 本研究旨在描述1990年至2003年间巴西及其各大宏观区域内50岁及以上人群的艾滋病（AIDS）发病情况，并分析该国1998年引入勃起功能障碍治疗药物前后的两个阶段。

**研究方法** 本研究开展生态学研究（ecological study），并对该人群中上报的艾滋病病例实施时空分析（space-time analysis）。以1990年至1997年确诊的艾滋病病例时间序列（time series）数据拟合线性回归（linear regression）模型，计算年度平均变化率与预期发病值，以此实现1998年至2003年间实际观测发病率与模型估计发病率的对比分析。

**研究结果** 本研究共纳入50岁及以上人群的25223例艾滋病病例进行分析，其中84%的病例集中于东南部与南部地区。截至1997年，这两个区域的年度平均变化率最高，分别为1.002和0.906，其后依次为中西部（0.570）、北部（0.441）及东北部（0.254）；巴西整体年度平均变化率为0.588。1998年之后，对1998年至2003年累计发病率的对比分析显示，除东北部地区外，其余所有区域的预期发病趋势均高于实际观测值。

**研究结论** 1990年至1997年间，50岁及以上人群的艾滋病增长趋势呈现较高的增长率；在该国引入勃起功能障碍治疗药物之后的时期，该人群的艾滋病发病仍呈增长趋势，但增长速度有所放缓。