The association between persistent cognitive difficulties and depression and functional outcomes in people with major depressive disorder.

BACKGROUND: Cognitive symptoms are common during and following episodes of depression. Little is known about the persistence of self-reported and performance-based cognition with depression and functional outcomes. METHODS: This is a secondary analysis of a prospective naturalistic observational clinical cohort study of individuals with recurrent major depressive disorder (MDD; N = 623). Participants completed app-based self-reported and performance-based cognitive function assessments alongside validated measures of depression, functional disability, and self-esteem every 3 months. Participants were followed-up for a maximum of 2-years. Multilevel hierarchically nested modelling was employed to explore between- and within-participant variation over time to identify whether persistent cognitive difficulties are related to levels of depression and functional impairment during follow-up. RESULTS: 508 individuals (81.5%) provided data (mean age: 46.6, s.d.: 15.6; 76.2% female). Increasing persistence of self-reported cognitive difficulty was associated with higher levels of depression and functional impairment throughout the follow-up. In comparison to low persistence of objective cognitive difficulty (<25% of timepoints), those with high persistence (>75% of timepoints) reported significantly higher levels of depression (B = 5.17, s.e. = 2.21, p = 0.019) and functional impairment (B = 4.82, s.e. = 1.79, p = 0.002) over time. Examination of the individual cognitive modules shows that persistently impaired executive function is associated with worse functioning, and poor processing speed is particularly important for worsened depressive symptoms. CONCLUSIONS: We replicated previous findings of greater persistence of cognitive difficulty with increasing severity of depression and further demonstrate that these cognitive difficulties are associated with pervasive functional disability. Difficulties with cognition may be an indicator and target for further treatment input.

Patch tests versus use tests in skin irritation risk assessment.

In the risk assessment of the ability of a substance or preparation to cause skin irritation, a patch test involving human volunteers is often seen as providing definitive information. However, the skin exposure conditions found in an occluded patch may be far removed from those in a particular use situation, not least for such reasons as the high dose per unit area, the duration of exposure and the maceration of the skin. Whilst these factors may enhance sensitivity in the identification of intrinsic hazard, they may do little to ensure accurate safety evaluation for real use. In this paper, we report data from a series of studies with an unmarketed facial skin cosmetic product. Whilst the product was unexpectedly highly irritating in a standard patch test in 30 volunteers, subsequent use tests, including a 6x daily open application to the elbow for 3 weeks and 2x daily application in a half-face test lasting 3 to 4 weeks and involving 52 volunteers failed to show any evidence of skin irritation. It is concluded that the most meaningful results for skin irritation risk assessment are likely to come from studies which involve relevant patterns of exposure.

Short term bioassay of cigarettes containing Cytrel tobacco supplement.

The toxicity of smoke from cigarettes containing tobacco, Cytrel tobacco supplement, or mixtures of the 2 materials, was investigated using 6 short term test methods. The tests used were rat trachea organ culture and mouse skin thickening tests, which may provide information on carcinogenicity, a ciliatoxicity test, an alveolar macrophage viability test, a haemolysis assay and a thiol inactivation test to provide measures of irritant and cytotoxic effects. In each case a response to the smoke from cigarettes containing tobacco alone was detected, while the magnitude of this response declined as the proportion of tobacco supplement in the blend increased. The least response was found with smoke from cigarettes containing Cytrel tobacco supplement alone.

Evaluation of three techniques of ventral decompression of the cervical spinal cord in the dog.

Three techniques for ventral decompression of the cervical spinal cord were performed on 21 dogs (3 groups of 7 dogs each). The techniques involved cutting various-sized defects in the vertebral bodies and disks of the cervical vertebral column. The defects were not filled with bone grafts. Two of the 3 techniques (short, wide defect and long, narrow defect) were successful, and the other technique (long, wide defect) gave questionable results.