Obesity is associated with sunburn diagnosis, with increasing effect estimates found for increasing body mass index (BMI), researchers reported in a study published in the Journal of Investigative Dermatology.
The cross-sectional study used the Truven Health MarketScan Health Risk Assessment Database (2009-2017), which includes de-identified commercial insurance claims data linked to self-reported health information. Eligible participants were 18 years of age or older who had BMI information and at least 1 medical encounter.
Multivariable logistic regression was used to assess the association between obesity and sunburn and included the covariates age, sex, region, insurance type, and health care use. Obesity (BMI ≥30) was evaluated as a binary variable.
Of 3.4 million patients who met the inclusion criteria, 6962 (mean [SD] age, 38  years; 58.8% women) had at least 1 sunburn diagnosis. The most common sunburn code was 692.7, sunburn or first-degree sunburn (63.1%, n = 11,502), followed by L55.9, sunburn, unspecified (14.3%, n = 2610). Patients who had 1 or more sunburn diagnosis were more likely to be women, younger, obese, and have higher health care use.
According to multivariable logistic regression adjusted for region and insurance type, binary obesity was statistically significantly associated with a sunburn diagnosis (odds ratio [OR] 1.26; 95% CI, 1.20-1.32), as were women (OR 1.25; 95% CI, 1.19-1.31), younger age (OR 0.98 per 1-year age increase; 95% CI, 0.98-0.98), and health care use (OR 1.02 per 1 additional outpatient encounter per year; 95% CI, 1.02-1.02).
Secondary and sensitivity analyses with BMI as a continuous variable yielded an OR of 1.01 per 1-unit increase in BMI (95% CI, 1.01-1.01). When the cohort was limited to patients with emergency department visits the outcome of sunburns yielded an OR of 1.51 (95% CI, 1.32-1.73) for obesity.
Stratification according to sex showed obesity ORs of 1.22 (95% CI 1.13-1.32) for men and 1.28 (95% CI, 1.20-1.36) for women. Stratification according to age category demonstrated obesity ORs of 1.42 (1.32-1.53) for those aged 18 to 34 years, 1.20 (1.09-1.33) for those aged 35 to 44 years, 1.08 (0.98-1.20) for those aged 45 to 54 years, and 1.01 (0.85-1.20) for those 55 years of age or older.
The study authors noted limitations to their findings. Weight and height were self-reported and subject to bias, race and ethnicity data were unavailable, and the analysis did not include uninsured individuals.
“A positive association between obesity and objectively determined sunburn supports the theory that sunburn, or intermittent intense ultraviolet exposure, may explain some of the increased risk of melanoma among patients with obesity,” stated the researchers. “Other mechanisms, particularly biologic, may contribute to these skin cancer risks as well.”
Garner DC, Niu J, Stender CF, et al. Association between obesity and sunburn diagnoses: a cross-sectional analysis in a large claims dataset. J Invest Dermatol. Published online November 26, 2021. doi:10.1016/j.jid.2021.11.019