Psoriasis and systemic inflammatory diseases: potential mechanistic links between skin disease and co-morbid conditions

Skin manifestations of obesity: a comparative study

BACKGROUND

Obesity is one of the world's biggest health problems nowadays. Little research has been done on the skin diseases that affect obese patients.

OBJECTIVE

To study the prevalence of skin manifestations in obese patients compared with a control group of normal-weight patients.

METHODS

A total of 76 obese patients [body mass index (BMI) ≥30 kg/m(2) ] and 73 with normal-weight volunteers (BMI 18.5-24.9 kg/m(2) ) were included in the study and had their complete medical history and skin examination evaluated by the same examiner. All patients were investigated for the presence of metabolic syndrome.

RESULTS

The dermatoses that showed a statistically significant relationship with obesity, compared with the control group were: striae (P < 0.001), plantar hyperkeratosis (P < 0.001), acrochordons (P = 0.007), intertrigo (P < 0.001), pseudoacanthosis nigricans (P < 0.001), keratosis pilaris (P = 0.006), lymphedema (P = 0.002) and bacterial infections (P = 0.05). The presence of striae, pseudoacanthosis nigricans and bacterial infections were also found to be correlated with the degree of obesity.

CONCLUSIONS

Obesity is strongly related to several skin alterations that could be considered as markers of excessive weight. Skin care of obese patients deserves particular attention, not only because of the high prevalence of cutaneous alteration but mainly because many of these disorders are preventable and could be treated, improving patient's quality of life.

Insulin-like Growth Factor-1, Psoriasis, and Inflammation: A Ménage à Trois?

Psoriatic patients have an accumulation of metabolic syndrome (MS) and cardiovascular diseases (CVD), likely mediated by systemic inflammation, and exhibiting low circulating levels of insulin-like growth factor (IGF)-I, a marker of MS and CVD in the general population. The aim of this study is to determine the association of IGF-I and inflammation, and to assess the cardio-metabolic risk calculating the visceral adiposity index (VAI), in a group of psoriatic patients without MS. IGF-I, fibrinogen, C-reactive protein (CRP), and interleukin (IL)-6 levels were determined in 20 patients with moderate to severe psoriasis (age range 23–77 yrs) without MS, according to criteria of the National Cholesterol Education Program's Adult Panel III (ATP III), and 20 age- and BMI-matched controls. The standard deviation score (SDS) of IGF-I levels according to age (zSDS), the homeostasis model assessment of insulin resistance (HOMA-IR), the whole-body insulin sensitivity index (ISI), and VAI were also calculated. Psoriasis Area and Severity Index (PASI) mean value was 17.8±11. HDL cholesterol and IGF-I zSDS values were lower (p<0.001) and waist circumference (p<0.001), VAI, fibrinogen, and IL-6 (p<0.005) were higher compared with controls, while HOMA-IR and ISI were not statistically different. Lower IGF-I zSDS values were associated to higher values of BMI (p=0.04), waist circumference, VAI (p<0.001), PASI (p=0.011), or IL-6 (p<0.001). At the multivariate analysis PASI was the major determinant of IGF-I zSDS (p=0.016), accounting for 37% of its variability. In a subset of psoriatic patients without MS, chronic inflammation might be an important modulator of low IGF-I status, as a further possible mechanistic link between psoriasis and associated metabolic co-morbidities. The negative correlation between age-related IGF-I values and VAI suggest the involvement of adipocyte dysfunction in low IGF-I status more than MS per se. Further studies are needed to address whether these results are valid also for other psoriatic patients.

Attributable risk estimate of severe psoriasis on major cardiovascular events

BACKGROUND

Recent studies suggest that psoriasis, particularly if severe, may be a risk factor for major adverse cardiac events, such as myocardial infarction, stroke, and mortality from cardiovascular disease. We compared the risk of major adverse cardiac events between patients with psoriasis and the general population and estimated the attributable risk of severe psoriasis.

METHODS

We performed a cohort study in the General Practice Research Database. Severe psoriasis was defined as receiving a psoriasis diagnosis and systemic therapy (N=3603). Up to 4 patients without psoriasis were selected from the same practices and start dates for each patient with psoriasis (N=14,330).

RESULTS

Severe psoriasis was a risk factor for major adverse cardiac events (hazard ratio 1.53; 95% confidence interval, 1.26-1.85) after adjusting for age, gender, diabetes, hypertension, tobacco use, and hyperlipidemia. After fully adjusted analysis, severe psoriasis conferred an additional 6.2% absolute risk of 10-year major adverse cardiac events.

CONCLUSION

Severe psoriasis confers an additional 6.2% absolute risk of a 10-year rate of major adverse cardiac events compared with the general population. This potentially has important therapeutic implications for cardiovascular risk stratification and prevention in patients with severe psoriasis. Future prospective studies are needed to validate these findings.

Investigation of new co-factors in 49 patients with pyoderma gangrenosum

BACKGROUND

Pyoderma gangrenosum is a rare, destructive, ulcerative neutrophilic dermatosis of unknown origin that has been investigated insufficiently in clinical studies. According to current textbooks, it is often associated with chronic inflammatory bowel diseases or other autoimmune disorders.

PATIENTS AND METHODS

We retrospectively analyzed data from 49 patients with pyoderma gangrenosum.

RESULTS

Our results showed that although only 6.1 % of patients had chronic inflammatory bowel disease, 22.4 % patients had a malignancy, 18.4 % had chronic renal insufficiency, and 42.8 % had anemia. A potentially relevant aspect that has received little attention is an association with endocrine diseases in 38.8 % of patients. 28.6 % of patients had diabetes. Given that 32.6 % of patients were obese, a potential association with metabolic syndrome may be considered as a possible new risk factor for pyoderma gangrenosum.

CONCLUSIONS

The clinical data from the present study are insufficient for drawing any firm conclusions. We did, however, observe an association between pyoderma gangrenosum and certain as yet unreported co-factors, in particular metabolic syndrome. This should be considered in further studies.

Systemic and vascular inflammation in patients with moderate to severe psoriasis as measured by [18F]-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT): a pilot study

OBJECTIVE

To evaluate the feasibility of using [18F]-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT) to detect and quantify systemic inflammation in patients with psoriasis.

DESIGN

Case series with a nested case-control study.

SETTING

Referral dermatology and preventive cardiology practices.

PARTICIPANTS

Six patients with psoriasis affecting more than 10% of their body surface area and 4 controls age and sex matched to 4 of the patients with psoriasis for a nested case-control study.

MAIN OUTCOME MEASURES

The FDG uptake in the liver, musculoskeletal structures, and aorta measured by mean standardized uptake value, a measure of FDG tracer uptake by macrophages and other inflammatory cells.

RESULTS

FDG-PET/CT identified numerous foci of inflammation in 6 patients with psoriasis within the skin, liver, joints, tendons, and aorta. Inflammation in the joints was observed in a patient with psoriatic arthritis as well as in 1 patient with no history of joint disease or joint symptoms. In a nested case-control study, FDG-PET/CT imaging demonstrated increased vascular inflammation in multiple segments of the aorta compared with controls. These findings persisted after adjustment for traditional cardiovascular risk factors in multivariate analysis (mean β = 0.33; P < .001). Patients with psoriasis further demonstrated increased hepatic inflammation after adjusting for cardiovascular risk factors (β = 0.18; P < .001), but the association was no longer significant when adjusted for alcohol intake (β = -0.25; P = .07).

CONCLUSION

FDG-PET/CT is a sensitive tool for identifying inflammation and can be used to identify clinically observed inflammation in the skin and subclinical inflammation in the blood vessels, joints, and liver of patients with psoriasis.

Psoriasis and cardiovascular risk: strength in numbers, part II

The Psoralen plus Ultraviolet-A (PUVA) cohort study has been a tremendous success in determining how a novel treatment (i.e., PUVA) affects the long-term risk of keratinocyte carcinoma. The ability to follow patients from the initial multicenter clinical trial for more than three decades has been a remarkable achievement in dermatoepidemiology. In this issue, Stern and Huibregtse report results from the PUVA follow-up study and conclude that only patients with exceptionally severe psoriasis have an increased overall mortality risk and that there is no significant risk of cardiovascular mortality associated with psoriasis. The results are in contrast to a large and growing body of literature that suggests patients with more severe psoriasis have a clinically significant increased risk of mortality in general and cardiovascular disease in particular. In addition, the authors found no association between severe psoriasis and obesity or between obesity and cardiovascular mortality, despite extensive literature establishing these associations. Basic principles of epidemiological study design may explain these discrepancies. Ultimately, however, randomized clinical trials will be necessary to determine whether severe psoriasis is in fact a "visible killer," as four decades ago (after many years of controversy) hypertension was recognized to be a "silent killer."