No abstract

A 2007 report by the International Agency for Research on Cancer classified night-shift work as possibly carcinogenic to humans, emphasizing, in particular, its association with breast cancer. Since this report and the publication of the last systematic review on this topic, several new studies have examined this association. Hence, to provide a comprehensive update on this topic, we performed a systematic review and meta-analysis. We searched Medline, Embase, CINAHL, Web of Science (Conference Proceedings), and ProQuest dissertations for studies published before March 1, 2012, along with a manual search of articles that cited or referenced the included studies. Included were observational case-control or cohort studies examining the association between night-shift work and breast carcinogenesis in women, which all ascertained and quantified night-shift work exposure. The search yielded 15 eligible studies for inclusion in the systematic review and meta-analysis. Using random-effects models, the pooled relative risk (RR) and 95 % confidence intervals (CIs) of breast cancer for individuals with ever night-shift work exposure was 1.21 (95 % CI, 1.00-1.47, p = 0.056, I (2) = 76 %), for short-term night-shift workers (<8 years) was 1.13 (95 % CI, 0.97-1.32, p = 0.11, I (2) = 79 %), and for long-term night-shift workers (≥8 years) was 1.04 (95 % CI, 0.92-1.18, p = 0.51, I (2) = 55 %), with substantial between-study heterogeneity observed in all analyses. Subgroup analyses suggested that flight attendants with international or overnight work exposure and nurses working night-shifts long-term were at increased risk of breast cancer, however, these findings were limited by unmeasured confounding. Overall, given substantial heterogeneity observed between studies in this meta-analysis, we conclude there is weak evidence to support previous reports that night-shift work is associated with increased breast cancer risk.

BackgroundThere is no consensus on whether screening titles alone or titles and abstracts together is the preferable strategy for inclusion of articles in a systematic review.MethodsTwo methods of screening articles for inclusion in a systematic review were compared: titles first versus titles and abstracts simultaneously. Each citation found in MEDLINE or Embase was reviewed by two physician reviewers for prespecified criteria: the citation included (1) primary data; (2) the exposure of interest; and (3) the outcome of interest.ResultsThere were 2965 unique citations. The titles first strategy resulted in an immediate rejection of 2558 (86%) of the records after reading the title alone, requiring review of 239 titles and abstracts, and subsequently 176 full text articles. The simultaneous titles and abstracts review led to rejection of 2782 citations (94%) and review of 183 full text articles. Interreviewer agreement to include an article for full text review using the titles-first screening strategy was 89%–94% (kappa = 0.54) and 96%–97% (kappa = 0.56) for titles and abstracts combined. The final systematic review included 13 articles, all of which were identified by both screening strategies (yield 100%, burden 114%). Precision was higher in the titles and abstracts method (7.1% versus 3.2%) but recall was the same (100% versus 100%), leading to a higher F-measure for the titles and abstracts approach (0.1327 versus 0.0619).ConclusionScreening via a titles-first approach may be more efficient than screening titles and abstracts together.

Neuromyelitis optica (NMO) is a recurrent inflammatory disease that preferentially targets the optic nerves and spinal cord leading to blindness and paralysis. The hallmarks of NMO include bilateral optic neuritis and longitudinally extensive transverse myelitis. Woman and African Americans are overrepresented in the US patient population. NMO is associated with the NMO-IgG biomarker, which targets the aquaporin-4 water channel on astrocytes. The humoral pathology of NMO lesions include IgG and IgM deposits and infiltration by granulocytes suggesting that the NMO-IgG may be involved in the pathogenesis of disease. This review of the recent NMO literature covers the clinical features, epidemiology, radiology and pathology of disease and includes discussion of the important basic science research work in the field.