Broccia G, Cocco P, Casula P
Department of Public Health, Occupational Health Section, University of Cagliari, Italy.
Haematologica. 2001 Jan;86(1):58-63.
The reasons for the worldwide increase in non-Hodgkin's lymphoma (NHL) are not clearly understood. We investigated whether an increasing trend over time has also occurred in the Italian region of Sardinia, the population of which exhibits peculiar genetic features, due to millenary isolation and pressure from 2,500 years of malarial endemism. We also investigated the geographic variation in NHL risk within the region.
We designed a descriptive epidemiology study of NHL among the Sardinian population by following up the incidence of this disease in the period 1974-1993. We calculated the standardized incidence rate (SIR) of NHL by year for the total population and by gender. The time trend of Hodgkin's disease (HD) was also evaluated as a comparison term and for validation purposes. We also mapped NHL risk in the 361 administrative units (communes) of the region.
NHL incidence in the Sardinian population over the whole study period was 7.5 x 10(-5) year(-1) (men: 8.2; women: 6.7), and increased from 4.1 in 1974 to 9.1 in 1993. The increasing trend was consistent by gender, and mostly affected subjects aged 55 years or older. Nodal and extra-nodal forms of NHL shared the same pattern of increasing incidence. Excluding the few NHL cases related to AIDS did not change the results. No such pattern was observed for HD incidence. The NHL incidence rate (age > or = 25 years) ranged from 0.0-60.0 x 10(-5) year-1 across communes. Areas at risk were located mainly in the northern part of the region, but risk among men was also elevated in the major urban area in southern Sardinia.
Our study shows that NHL incidence increased 2.2-fold in Sardinia from 1974 to 1993, a finding which is consistent with other world-wide report. The risk has risen in a few areas, mainly in central and northern Sardinia and in the major urban areas. Analytic studies are under way to investigate a broad range of risk factors, including viral, occupational, and environmental factors, that might account for our results.
全球非霍奇金淋巴瘤（NHL）发病率上升的原因尚不清楚。我们调查了在意大利撒丁岛地区是否也存在随时间推移的上升趋势，该地区人口由于数千年的隔离以及2500年疟疾地方病的影响而具有独特的遗传特征。我们还调查了该地区内NHL风险的地理差异。
我们通过追踪1974 - 1993年期间该疾病的发病率，对撒丁岛人群中的NHL进行了描述性流行病学研究。我们计算了总人口和按性别划分的NHL标准化发病率（SIR）。霍奇金病（HD）的时间趋势也作为比较项并用于验证目的进行了评估。我们还绘制了该地区361个行政单位（公社）的NHL风险图。
在整个研究期间，撒丁岛人群中的NHL发病率为7.5×10⁻⁵/年（男性：8.2；女性：6.7），并从1974年的4.1上升至1993年的9.1。这种上升趋势在性别上是一致的，并且主要影响55岁及以上的人群。NHL的结内和结外形式具有相同的发病率上升模式。排除少数与艾滋病相关的NHL病例并未改变结果。HD发病率未观察到这种模式。各公社的NHL发病率（年龄≥25岁）范围为0.0 - 60.0×10⁻⁵/年。高风险地区主要位于该地区北部，但撒丁岛南部的主要城市地区男性的风险也有所升高。
我们的研究表明，1974年至1993年期间撒丁岛的NHL发病率增加了2.2倍，这一发现与其他全球报告一致。风险在一些地区有所上升，主要在撒丁岛中部和北部以及主要城市地区。正在进行分析研究以调查可能解释我们结果的广泛风险因素，包括病毒、职业和环境因素。
