Psoriasis for Seniors

The evaluation and treatment of psoriasis in older patients have long been issues of interest among clinicians. This population is at risk from comorbidities associated with psoriasis. In addition, the potential for increased side effects of therapies in this population has been a concern.

Takeshita et al¹ recently published a study evaluating the prevalence of psoriasis and its treatments in the elderly population. The authors point out that despite major advances in the field of psoriasis, there are large gaps in knowledge among the increasing elderly population. The authors noted that this study is the first to evaluate the epidemiology and treatment of psoriasis in the US population using Medicare.¹

Utilizing 8 different algorithms, claims-based psoriasis prevalence was calculated for 799,607 beneficiaries in the 2011 Medicare 5% sample (random 5% sample of Medicare beneficiaries) and was found to range from 0.51% to 1.23%. For the main analyses, a diagnosis of psoriasis was established by the presence of at least 2 inpatient or outpatient claims for psoriasis.¹

The authors reported the following characteristics for the study population¹: the mean age was 68.6 years; 43.2% of the participants were male; 88.8% were white; 5.1% were black; 2.2% were Hispanic; and 3.9% were other or unknown race. Regional distribution of residence was as follows: 24.0% in the northeast, 23.0% in the Midwest, 36.2% in the south, and 16.6% in the west. County-level mean per capita income was $40,115; 63.6% of beneficiaries qualified for Medicare based on age alone; 58.4% were not receiving a Medicare Part D low-income subsidy (LIS); and 19.0% were receiving Part D plans with enhanced alternative coverage. The most commonly coded comorbidities were cardiometabolic disorders (67.6% hypertension; 59.9% dyslipidemia; 32.4% diabetes); 23.5% had atherosclerotic outcomes. The prevalence of obesity was relatively low at 9.3% and the prevalence of psoriatic arthritis was 9.4%. Other comorbid diseases of interest included depression (17.1%), renal disease (9.8%), liver disease (5.1%), and inflammatory bowel disease (1.2%).¹

The analysis of psoriatic therapy revealed that topical therapies were used by 76.6% of the total psoriasis sample, the majority of which were topical corticosteroids.¹ Phototherapy was used by 7% and oral systemic medications were used by 14.3% (the majority received methotrexate). Biologics were received by 10.2%, and of those patients, 44.4% received etanercept, 34.2% adalimumab, 22.7% infliximab, and 7.9% ustekinumab.¹

There were several interesting findings in the analysis.¹ Oral systemic medications such as methotrexate were the most common therapies for moderate to severe psoriasis, followed by biologics.¹ Associated comorbidities for which biologic therapy is indicated (ie, ankylosing spondylitis, inflammatory bowel disease, psoriatic arthritis) were associated with greater odds of receiving treatment with biologics. Individuals lacking LIS under the Part D plan had 70% lower odds of receiving biologics compared with those with LIS that allowed for lower out-of-pocket costs. The odds of having received biologics were 69% lower for black individuals compared to white patients.¹

This study helps us to further understand the patterns of psoriasis and its treatment in the elderly population. Some of the findings are in line with our current thinking regarding comorbidities and therapies used, while other observations, such as a lower number of untreated patients than expected, are more surprising. Interestingly, this study identified potential financial and racial barriers to the receipt of biologic therapies. These barriers are important issues to address as we strive to better care for our psoriatic population.