Associations between lifestyle factors and life quality in people living with psoriasis: results of the Asking People with Psoriasis about Lifestyle and Eating (APPLE) cross-sectional study

BACKGROUND: Lifestyle factors have the potential to enhance wellbeing and quality of life (QoL). OBJECTIVES: To identify lifestyle patterns among UK-based adults with psoriasis and examine associations with QoL. METHODS: This was a cross-sectional analysis of the Asking People with Psoriasis about Lifestyle and Eating (APPLE) study (n = 353). QoL, body mass index (BMI) and physical activity were assessed using the Dermatology Life Quality Index (DLQI), self-reported weight and height, and the International Physical Activity Questionnaire. RESULTS: Participant demography was: 82% women; mean (SD) age of all participants was 41 (13) years; and BMI was 27 (7) kg m-2. When fully adjusted for age, sex, smoking and alcohol use, compared with individuals in the highest BMI tertile [35 (5) kg m-2], those in the lowest tertile [21 (2) kg m-2] reported a 71% reduced likelihood of QoL impairments (odds ratio 0.29, 95% confidence interval 0.14-0.59; adjusted P < 0.01). Dairy-free, gluten-free and pescatarian diets were more frequently adopted by individuals reporting healthy BMIs (≈ 24 kg m-2; adjusted P < 0.05). Higher levels of physical activity [2932 (1509) metabolic equivalent of task min per week], and adequate sleep duration [7 (0) h daily] were associated with lower odds of QoL impairments, although attenuated by multiple testing. Participants affected by embarrassment or self--consciousness related to their psoriasis engaged in less vigorous-intensity and walking activities compared with those who were less affected (adjusted P < 0.05). CONCLUSIONS: Assessing weight status and physical activity in individuals reporting high DLQI scores may help identify modifiable behaviours contributing to poorer QoL and thereby shape interventions.