Dermatological screening of a middle-aged and elderly population: the Rotterdam Study

Dear Editor, The prevalence of several skin diseases increases with age, partly due to age‐related physiopathological alterations.1 The global burden of disease project (GBD)2 presented a comprehensive overview of the burden due to skin diseases across different age groups. However, the point prevalences of many common skin diseases, especially in older people and noninstitutionalized settings, are still unknown.3 In this study, we estimated the point prevalence and age‐ and sex‐adjusted standardized prevalence rates of common inflammatory and (pre)malignant skin diseases in a cross‐sectional study in a middle‐aged to elderly population (Appendix S1; see Supporting Information). In 2010, full body skin examinations (FBSEs) were introduced in the Rotterdam Study,4 a prospective population‐based cohort study of people aged ≥ 45 years. Since the start of study, in 1989, all citizens of Ommoord (a district of Rotterdam) were invited to participate, with an overall response of 72% during three invitation cycles. The study design and follow‐up are detailed in Hofman et al.4 At FBSE, all participants were aged ≥ 50 years. The FBSEs were carried out by dermatology‐trained physicians who checked for common skin diseases, including (pre)malignancies, eczema, psoriasis, seborrhoeic dermatitis and clinical signs of venous insufficiency (Appendix S2; see Supporting Information). Age‐ and sex‐adjusted standardized prevalence rates (PR) were calculated per 100 000 persons aged ≥ 50 years and standardized to the Revised European Standard Population (Appendix S3; see Supporting Information). In total, 5365 participants (median age 67·2 years; interquartile range 61·6–74·8) were examined. The age‐ and sex‐adjusted prevalence of skin diseases are presented in Table 1. Xerosis cutis was present in 66% of participants. Premalignant and malignant skin diseases were very common, comprising 48% of all identified skin diseases (Fig. S1; see Supporting Information). Actinic keratosis (AK) was found in 1399 (26·1%) participants; 234 (4·4%) showed one or more cutaneous malignancies. Basal cell carcinomas (BCCs) were most common but melanomas, squamous cell carcinomas (SCCs) and mycosis fungoides were also diagnosed (Table 1). Seborrhoeic dermatitis was the most common nonmalignant disorder, with a standardized prevalence rate of 17 685 per 100 000 men and 9588 per 100 000 women. Characteristics of screened Rotterdam Study participants (n =5365) with standardized prevalence rates per 100 000 CI, confidence interval; IQR, interquartile range; SCC, squamous cell carcinoma. aSeventeen participants had two or more basal cell carcinomas (BCCs). bParticipants with one or more suspected BCCs referred to a general practitioner or another hospital (not Erasmus Medical Center) and of whom we had no further medical information or pathological confirmation. Characteristics of screened Rotterdam Study participants (n =5365) with standardized prevalence rates per 100 000 CI, confidence interval; IQR, interquartile range; SCC, squamous cell carcinoma. aSeventeen participants had two or more basal cell carcinomas (BCCs). bParticipants with one or more suspected BCCs referred to a general practitioner or another hospital (not Erasmus Medical Center) and of whom we had no further medical information or pathological confirmation. Skin disorders are often not identified, or neglected. In this cohort, we found a high prevalence of (pre)malignant disorders. About a quarter of participants were diagnosed with AK, a potential precursor of SCC. The point prevalence of SCCs is lower than expected compared with melanomas. This could be because melanomas more often develop on less visible body sites and are often subclinical, contrasting with SCC. Therefore, melanomas are more likely to be detected during screening. About one in 25 participants was diagnosed with at least one cutaneous malignancy. This high prevalence suggests that primary care practitioners should be more alert to detect suspicious skin lesions in the middle‐aged and elderly population. The U.S. Preventive Services Task Force recently concluded that there is insufficient evidence for skin cancer screening in asymptomatic adults.5 However, screening via self‐examination, case finding by physicians or screening of high‐risk subgroups were considered. The German skin screening programme showed that screening of all adults had a limited impact on melanoma‐related mortality. However, the lower number needed to treat in elderly patients, and the higher skin cancer prevalence in men, suggest that elderly men are potentially a target group for skin screening.5 Also, skin cancer awareness campaigns should not be restricted to melanomas but should include keratinocytic cancers given their prevalence and associated disease burden.6 Although most prevalent diseases identified in this study (e.g. seborrhoeic dermatitis, psoriasis, venous disease and eczema) have low mortality rates, they can severely affect quality of life.7 Simple measures such as education on general skin care (e.g. using mild cleansers instead of water and soap in xerosis cutis) might be a fast and easy way to manage some of these conditions.8 Also, treatment of varicose veins in patients with oedema or skin changes might reduce symptoms and prevent the development of venous leg ulcers.9 Most skin diseases may only cause a relatively small burden on the individual patient level, but due to the high prevalence, the societal burden is substantial. As stated in a recent report from the World Health Organization on ageing and health,10 changes in health care will be needed to adapt to the continuing increase in life expectancy and the subsequent higher proportion of the elderly population living with comorbidity, including skin diseases. The high prevalence of skin malignancies found in this population‐based screening indicate that the total burden of skin diseases is beyond the recent estimates presented by the GBD project. Therefore, the diagnosis, prevention and treatment of skin disease should get sufficient priority in general healthcare education and policies. Funding sources: This study was funded by the Netherlands Organisation for Health Research and Development; ZonMW; Vidi grant no. 91711315. Conflicts of interest: none declared. Appendix S1. Selection. Appendix S2. Case definitions. Appendix S3. Statistical analysis. Fig S1. Total identified skin diseases.