Does weight loss reduce the severity and incidence of psoriasis or psoriatic arthritis? A Critically Appraised Topic.

CLINICAL QUESTION: Does weight loss reduce the severity and incidence of psoriasis or psoriatic arthritis (PsA) in obese individuals? BACKGROUND: Obesity presents a rising public health challenge and is more prevalent among individuals with psoriasis or PsA than in the general population. Longitudinal population-based studies suggest a causal role for obesity in psoriasis and PsA onset and that obesity drives greater disease severity. METHODS: We systematically reviewed evidence within the MEDLINE, Embase and CENTRAL databases and clinical trials registries examining lifestyle, pharmacological and surgical weight loss interventions in the treatment and prevention of psoriasis and PsA in obese individuals. Meta-analysis was conducted using random-effects models, followed by sensitivity analyses. RESULTS: Of 176 full-text articles reviewed, 14 met the inclusion criteria. Meta-analysis of six randomized control trials (RCTs) confirmed that weight loss following lifestyle interventions (diet or physical activity) improves psoriasis compared with control [mean change in Psoriasis Area and Severity Index -2·59, 95% confidence interval (CI) -4·09 to -1·09; P < 0·001]. One RCT demonstrated a greater likelihood of achieving minimal PsA activity following diet-induced weight loss (odds ratio 4·20, 95% CI 1·82-9·66; P < 0·001). Three studies of pharmacological treatments reported conflicting results, and no RCTs of bariatric surgery were identified. Two cohort studies suggested that bariatric surgery, particularly gastric bypass, reduces the risk of developing psoriasis (hazard ratio 0·52, 95% CI 0·33-0·81; P < 0·01). CONCLUSIONS: These limited data indicate that weight loss can improve pre-existing psoriasis and PsA, and prevent the onset of psoriasis in obese individuals. Together with the National Institute for Health and Care Excellence obesity guidance, this informed a local obesity screening and management pathway, providing multidisciplinary weight loss interventions alongside conventional skin-focused care for patients with psoriasis.

Scaffolds for hand tissue engineering: the importance of surface topography.

Tissue engineering is believed to have great potential for the reconstruction of the hand after trauma, congenital absence and tumours. Due to the presence of multiple distinct tissue types, which together function in a precisely orchestrated fashion, the hand counts among the most complex structures to regenerate. As yet the achievements have been limited. More recently, the focus has shifted towards scaffolds, which provide a three-dimensional framework to mimic the natural extracellular environment for specific cell types. In particular their surface structures (or topographies) have become a key research focus to enhance tissue-specific cell attachment and growth into fully functioning units. This article reviews the current understanding in hand tissue engineering before focusing on the potential for scaffold topographical features on micro- and nanometre scales to achieve better functional regeneration of individual and composite tissues.