Chronic Skin Disease and Levels of Physical Activity in 17,777 Spanish Adults: A Cross-Sectional Study

Background: To date there is limited literature on the prevalence of chronic skin conditions and levels of physical activity (PA) in Spain. Aim: The present study aims to (i) determine the prevalence of chronic skin disease and (ii) compare levels of PA in those with chronic skin disease to those without in a large representative sample of Spanish adults aged 15‐69 years. Methods: Data from the Spanish National Health Survey 2017 were analysed. Chronic skin disease was assessed using a yes‐no question. PA was measured using the short form of the International Physical Activity Questionnaire (IPAQ). Total PA metabolic equivalent of task (MET)‐minutes/week were calculated, and PA was included in the analyses as a continuous and a five‐category variable. Results: This cross‐sectional study included 17,777 participants [52.0% women; mean (standard deviation) age 45.8 (14.1) years]. There were 940 (5.3%) adults with chronic skin disease. After adjusting for several potential confounders, there was a negative association between chronic skin disease and PA [odds ratio (OR)=0.87, 95% CI=0.76–1.00]. The association was significant in men (OR=0.76, 95% CI=0.62‐0.93) but not in women (OR=0.97, 95% CI=0.81‐1.16). Conclusions: In this large representative sample of Spanish adults, the prevalence of chronic skin disease was low. Levels of PA in men with chronic skin conditions, but not in women, were lower than those without

Population‐based Clinical Practice Research Datalink study using algorithm modelling to identify the true burden of hidradenitis suppurativa

Background: Epidemiology data regarding hidradenitis suppurativa (HS) are conflicting and prevalence estimates vary 80-fold, from 0·05% in a population-based study to 4%. Objectives: To assess the hypothesis that previous population-based studies underestimated true HS prevalence by missing undiagnosed cases. Methods: We performed a population-based observational and case–control study using the U.K. Clinical Practice Research Datalink (CPRD) linked to hospital episode statistics data. Physician-diagnosed cases in the CPRD were identified from specific Read codes. Algorithms identified unrecognized ‘proxy’ cases, with at least five Read code records for boils in flexural skin sites. Validation of proxy cases was undertaken with general practitioner (GP) questionnaires to confirm criteria-diagnosed cases. A case–control study assessed disease associations. Results: On 30 June 2013, 23 353 physician-diagnosed HS cases were documented in 4 364 308 research-standard records. In total, 68 890 proxy cases were identified, reduced to 10 146 criteria-diagnosed cases after validation, extrapolated from 107 completed questionnaires (61% return rate). Overall point prevalence was 0·77% [95% confidence interval (CI) 0·76–0·78%]. An additional 18 417 cases had a history of one to four flexural skin boils. In physician-diagnosed cases, odds ratios (ORs) for current smoker and obesity (body mass index &gt; 30 kg m-2) were 3·61 (95% CI 3·44–3·79) and 3·29 (95% CI 3·14–3·45). HS was associated with type 2 diabetes, Crohn disease, hyperlipidaemia, acne and depression, and not associated with ulcerative colitis or polycystic ovary syndrome. Conclusions: Contrary to results of previous population-based studies, HS is relatively common, with a U.K. prevalence of 0·77%, one-third being unrecognized, criteria-diagnosed cases using the most stringent disease definition. If individuals with probable cases are included, HS prevalence rises to 1·19%.</p